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• How to design a C / C++ library to be usable in many client languages?

  - by Brian Schimmel

  I'm planning to code a library that should be usable by a large number of people in on a wide spectrum of platforms. What do I have to consider to design it right? To make this questions more specific, there are four "subquestions" at the end. Choice of language Considering all the known requirements and details, I concluded that a library written in C or C++ was the way to go. I think the primary usage of my library will be in programs written in C, C++ and Java SE, but I can also think of reasons to use it from Java ME, PHP, .NET, Objective C, Python, Ruby, bash scrips, etc... Maybe I cannot target all of them, but if it's possible, I'll do it. Requirements It would be to much to describe the full purpose of my library here, but there are some aspects that might be important to this question: The library itself will start out small, but definitely will grow to enormous complexity, so it is not an option to maintain several versions in parallel. Most of the complexity will be hidden inside the library, though The library will construct an object graph that is used heavily inside. Some clients of the library will only be interested in specific attributes of specific objects, while other clients must traverse the object graph in some way Clients may change the objects, and the library must be notified thereof The library may change the objects, and the client must be notified thereof, if it already has a handle to that object The library must be multi-threaded, because it will maintain network connections to several other hosts While some requests to the library may be handled synchronously, many of them will take too long and must be processed in the background, and notify the client on success (or failure) Of course, answers are welcome no matter if they address my specific requirements, or if they answer the question in a general way that matters to a wider audience! My assumptions, so far So here are some of my assumptions and conclusions, which I gathered in the past months: Internally I can use whatever I want, e.g. C++ with operator overloading, multiple inheritance, template meta programming... as long as there is a portable compiler which handles it (think of gcc / g++) But my interface has to be a clean C interface that does not involve name mangling Also, I think my interface should only consist of functions, with basic/primitive data types (and maybe pointers) passed as parameters and return values If I use pointers, I think I should only use them to pass them back to the library, not to operate directly on the referenced memory For usage in a C++ application, I might also offer an object oriented interface (Which is also prone to name mangling, so the App must either use the same compiler, or include the library in source form) Is this also true for usage in C# ? For usage in Java SE / Java EE, the Java native interface (JNI) applies. I have some basic knowledge about it, but I should definitely double check it. Not all client languages handle multithreading well, so there should be a single thread talking to the client For usage on Java ME, there is no such thing as JNI, but I might go with Nested VM For usage in Bash scripts, there must be an executable with a command line interface For the other client languages, I have no idea For most client languages, it would be nice to have kind of an adapter interface written in that language. I think there are tools to automatically generate this for Java and some others For object oriented languages, it might be possible to create an object oriented adapter which hides the fact that the interface to the library is function based - but I don't know if its worth the effort Possible subquestions is this possible with manageable effort, or is it just too much portability? are there any good books / websites about this kind of design criteria? are any of my assumptions wrong? which open source libraries are worth studying to learn from their design / interface / souce? meta: This question is rather long, do you see any way to split it into several smaller ones? (If you reply to this, do it as a comment, not as an answer)

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• [C#] Not enough memory or not enough handles?

  - by Nayan

  I am working on a large scale project where a custom (pretty good and robust) framework has been provided and we have to use that for showing up forms and views. There is abstract class StrategyEditor (derived from some class in framework) which is instantiated whenever a new StrategyForm is opened. StrategyForm (a customized window frame) contains StrategyEditor. StrategyEditor contains StrategyTab. StrategyTab contains StrategyCanvas. This is a small portion of the big classes to clarify that there are many objects that will be created if one StrategyForm object is allocated in memory at run-time. My component owns all these classes mentioned above except StrategyForm whose code is not in my control. Now, at run-time, user opens up many strategy objects (which trigger creation of new StrategyForm object.) After creating approx. 44 strategy objects, we see that the USER OBJECT HANDLES (I'll use UOH from here onwards) created by the application reaches to about 20k+, while in registry the default amount for handles is 10k. Read more about User Objects here. Testing on different machines made it clear that the number of strategy objects opened is different for message to pop-up - on one m/c if it is 44, then it can be 40 on another. When we see the message pop-up, it means that the application is going to respond slowly. It gets worse with few more objects and then creation of window frames and subsequent objects fail. We first thought that it was not-enough-memory issue. But then reading more about new in C# helped in understanding that an exception would be thrown if app ran out of memory. This is not a memory issue then, I feel (task manager also showed 1.5GB+ available memory.) M/C specs Core 2 Duo 2GHz+ 4GB RAM 80GB+ free disk space for page file Virtual Memory set: 4000 - 6000 My questions Q1. Does this look like a memory issue and I am wrong that it is not? Q2. Does this point to exhaustion of free UOHs (as I'm thinking) and which is resulting in failure of creation of window handles? Q3. How can we avoid loading up of an StrategyEditor object (beyond a threshold, keeping an eye on the current usage of UOHs)? (we already know how to fetch number of UOHs in use, so don't go there.) Keep in mind that the call to new StrategyForm() is outside the control of my component. Q4. I am bit confused - what are Handles to user objects exactly? Is MSDN talking about any object that we create or only some specific objects like window handles, cursor handles, icon handles? Q5. What exactly cause to use up a UOH? (almost same as Q4) I would be really thankful to anyone who can give me some knowledgeable answers. Thanks much! :)

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• Recommended integration mechanism for bi-directional, authenticated, encrypted connection in C clien

  - by rcampbell

  Let me first give an example. Imagine you have a single server running a JVM application. This server keeps a collection of N equations, once for each client: Client #1: 2x Client #2: 1 + y Client #3: z/4 This server includes an HTTP interface so that random visitors can type https://www.acme.com/client/3 int their browsers and see the latest evaluated result of z/4. The tricky part is that either the client or the server may change the variable value at any time, informing the other party immediately. More specifically, Client #3 - a C app - can initially tell the server that z = 20. An hour later that same client informs the server that z = 23. Likewise the server can later inform the client that z = 28. As caf pointed out in the comments, there can be a race condition when values are changed by the client and server simultaneously. The solution would be for both client and server to send the operation performed in their message, which would need to be executed by the other party. To keep things simple, let's limit the operations to (commutative) addition, allowing us to disregard message ordering. For example, the client seeds the server with z = 20: server:z=20, client:z=20 server sends {+3} message (so z=23 locally) & client sends {-2} message (so z=18 locally) at the exact same time server receives {-2} message at some point, adds to his local copy so z=21 client receives {+3} message at some point, adds to his local copy so z=21 As long as all messages are eventually evaluated by both parties, the correct answer will eventually be given to the users of the client and server since we limited ourselves to commutative operations (addition of 3 and -2). This does mean that both client and server can be returning incorrect answers in the time it takes for messages to be exchanged and processed. While undesirable, I believe this is unavoidable. Some possible implementations of this idea include: Open an encrypted, always on TCP socket connection for communication Pros: no additional infrastructure needed, client and server know immediately if there is a problem (disconnect) with the other party, fairly straightforward (except the the encryption), native support from both JVM and C platforms Cons: pretty low-level so you end up writing a lot yourself (protocol, delivery verification, retry-on-failure logic), probably have a lot of firewall headaches during client app installation Asynchronous messaging (ex: ActiveMQ) Pros: transactional, both C & Java integration, free up the client and server apps from needing retry logic or delivery verification, pretty straightforward encryption, easy extensibility via message filters/routers/etc Cons: need additional infrastructure (message server) which must never fail, Database or file system as asynchronous integration point Same pros/cons as above but messier RESTful Web Service Pros: simple, possible reuse of the server's existing REST API, SSL figures out the encryption problem for you (maybe use RSA key a la GitHub for authentication?) Cons: Client now needs to run a C HTTP REST server w/SSL, client and server need retry logic. Axis2 has both a Java and C version, but you may be limited to SOAP. What other techniques should I be evaluating? What real world experiences have you had with these mechanisms? Which do you recommend for this problem and why?

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• Trouble in ActiveX multi-thread invoke javascript callback routine

  - by code0tt

  everyone. I'm get some trouble in ActiveX programming with ATL. I try to make a activex which can async-download files from http server to local folder and after download it will invoke javascript callback function. My solution: run a thread M to monitor download thread D, when D is finish the job, M is going to terminal themself and invoke IDispatch inferface to call javascript function. **************** THERE IS MY CODE: **************** /* javascript code */ funciton download() { var xfm = new ActiveXObject("XFileMngr.FileManager.1"); xfm.download( 'http://somedomain/somefile','localdev:\\folder\localfile',function(msg){alert(msg);}); } /* C++ code */ // main routine STDMETHODIMP CFileManager::download(BSTR url, BSTR local, VARIANT scriptCallback) { CString csURL(url); CString csLocal(local); CAsyncDownload download; download.Download(this, csURL, csLocal, scriptCallback); return S_OK; } // parts of CAsyncDownload.h typedef struct tagThreadData { CAsyncDownload* pThis; } THREAD_DATA, *LPTHREAD_DATA; class CAsyncDownload : public IBindStatusCallback { private: LPUNKNOWN pcaller; CString csRemoteFile; CString csLocalFile; CComPtr<IDispatch> spCallback; public: void onDone(HRESULT hr); HRESULT Download(LPUNKNOWN caller, CString& csRemote, CString& csLocal, VARIANT callback); static DWORD __stdcall ThreadProc(void* param); }; // parts of CAsyncDownload.cpp void CAsyncDownload::onDone(HRESULT hr) { if(spCallback) { TRACE(TEXT("invoke callback function\n")); CComVariant vParams[1]; vParams[0] = "callback is working!"; DISPPARAMS params = { vParams, NULL, 1, 0 }; HRESULT hr = spCallback->Invoke(0, IID_NULL, LOCALE_USER_DEFAULT, DISPATCH_METHOD, &params, NULL, NULL, NULL); if(FAILED(hr)) { CString csBuffer; csBuffer.Format(TEXT("invoke failed, result value: %d \n"),hr); TRACE(csBuffer); }else { TRACE(TEXT("invoke was successful\n")); } } } HRESULT CAsyncDownload::Download(LPUNKNOWN caller, CString& csRemote, CString& csLocal, VARIANT callback) { CoInitializeEx(NULL, COINIT_MULTITHREADED); csRemoteFile = csRemote; csLocalFile = csLocal; pcaller = caller; switch(callback.vt){ case VT_DISPATCH: case VT_VARIANT:{ spCallback = callback.pdispVal; } break; default:{ spCallback = NULL; } } LPTHREAD_DATA pData = new THREAD_DATA; pData->pThis = this; // create monitor thread M HANDLE hThread = CreateThread(NULL, 0, ThreadProc, (void*)(pData), 0, NULL); if(!hThread) { delete pData; return HRESULT_FROM_WIN32(GetLastError()); } WaitForSingleObject(hThread, INFINITE); CloseHandle(hThread); CoUninitialize(); return S_OK; } DWORD __stdcall CAsyncDownload::ThreadProc(void* param) { LPTHREAD_DATA pData = (LPTHREAD_DATA)param; // here, we will create http download thread D // when download job is finish, call onDone method; pData->pThis->onDone(S_OK); delete pData; return 0; } **************** CODE FINISH **************** OK, above is parts of my source code, if I call onDone method in sub-thread, I will get OLE ERROR(-2147418113 (8000FFFF) Catastrophic failure.). Did I miss something? please help me to figure it out.

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• Why do some questions get closed for no reason? [closed]

  - by IVlad

  Recently there was a question asking about generating all subsets of a set using a stack and a queue, which was closed (and now deleted it seems) as not a real question for no good reason, since it didn't fit into any of these conditions: It's difficult to tell what is being asked here. No, it was clear what was being asked. This question is ambiguous, vague, incomplete, or rhetorical and cannot be reasonably answered in its current form. Not ambiguous, not vague, not incomplete, definitely not rhetorical and could easily be answered if one knew the solution. Now, the exact same thing has happened with this question: http://stackoverflow.com/questions/2791982/a-shortest-path-problem-with-superheroes-and-intergalactic-journeys/2793746#2793746 I am interested in hearing a logical argument for why that question is either ambiguous, vague, incomplete, rhetorical or cannot reasonably be answered in its current form. It seems that (the same bunch of) people like to close questions that they think are homework questions, especially when they think people want to be served the solution on a platter, which is also not the case: Any suggestions or ideas of how this problem might be solved would be most welcomed. Most of the time the people asking these questions are very reasonable and appreciate even the most vague idea, yet their question is closed. Let's go further and assume that it IS a homework problem. So what? When I registered here I didn't see any rule that said not to post homework problems, nor do I see such a rule now. What is wrong with posting homework problems that makes people hunt them down with a passion to close them without even reading the entire question body? This site is full of questions asked by people who get paid to know the things they are asking, yet their questions are considered fine. How is solving someone's homework problem worse? In some places (like where I live), computer science is a mandatory high school subject, and not everyone is interested in it. How is helping at least those people worse than doing someone's JOB? Not answering homework questions is fine and it's everyone's choice, but I consider closing them to be an act of power abuse, selfishness, and an insult to the fellow community members who are also interested in a solution or want feedback on their proposed solution. So my questions are: - Why do questions like the above get closed for reasons that do not apply? Why do you close them? Why don't you? - Why doesn't a vote to reopen a question reopen it automatically? Needing 5 votes for a reopen takes too long, and it's not fair because one reopen vote basically cancels out a close vote, making it 4 close votes (or 5 to 1, which is the same as only 4 people wanting to close the question), which isn't enough to close the question. I think a question should only be closed when CloseVotes - ReopenVotes >= 5. I'm hoping this will stay up, but I realize it probably won't. In either case, I think this is worth saying and discussing, since it IS community-related.

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• inserting new relationship data in core-data

  - by michael

  My app will allow users to create a personalised list of events from a large list of events. I have a table view which simply displays these events, tapping on one of them takes the user to the event details view, which has a button "add to my events". In this detailed view I own the original event object, retrieved via an NSFetchedResultsController and passed to the detailed view (via a table cell, the same as the core data recipes sample). I have no trouble retrieving/displaying information from this "event". I am then trying to add it to the list of MyEvents represented by a one to many (inverse) relationship: This code: NSManagedObjectContext *context = [event managedObjectContext]; MyEvents *myEvents = (MyEvents *)[NSEntityDescription insertNewObjectForEntityForName:@"MyEvents" inManagedObjectContext:context]; [myEvents addEventObject:event];//ERROR And this code (suggested below): //would this add to or overwrite the "list" i am attempting to maintain NSManagedObjectContext *context = [event managedObjectContext]; MyEvents *myEvents = (MyEvents *)[NSEntityDescription insertNewObjectForEntityForName:@"MyEvents" inManagedObjectContext:context]; NSMutableSet *myEvent = [myEvents mutableSetValueForKey:@"event"]; [myEvent addObject:event]; //ERROR Bot produce (at the line indicated by //ERROR): *** -[NSComparisonPredicate evaluateWithObject:]: message sent to deallocated instance Seems I may have missed something fundamental. I cant glean any more information through the use of debugging tools, with my knowledge of them. 1) Is this a valid way to compile and store an editable list like this? 2) Is there a better way? 3) What could possibly be the deallocated instance in error? -- I have now modified the Event entity to have a to-many relationship called "myEvents" which referrers to itself. I can add Events to this fine, and logging the object shows the correct memory addresses appearing for the relationship after a [event addMyEventObject:event];. The same failure happens right after this however. I am still at a loss to understand what is going wrong. This is the backtrace #0 0x01f753a7 in ___forwarding___ () #1 0x01f516c2 in __forwarding_prep_0___ () #2 0x01c5aa8f in -[NSFetchedResultsController(PrivateMethods) _preprocessUpdatedObjects:insertsInfo:deletesInfo:updatesInfo:sectionsWithDeletes:newSectionNames:treatAsRefreshes:] () #3 0x01c5d63b in -[NSFetchedResultsController(PrivateMethods) _managedObjectContextDidChange:] () #4 0x0002e63a in _nsnote_callback () #5 0x01f40005 in _CFXNotificationPostNotification () #6 0x0002bef0 in -[NSNotificationCenter postNotificationName:object:userInfo:] () #7 0x01bbe17d in -[NSManagedObjectContext(_NSInternalNotificationHandling) _postObjectsDidChangeNotificationWithUserInfo:] () #8 0x01c1d763 in -[NSManagedObjectContext(_NSInternalChangeProcessing) _createAndPostChangeNotification:withDeletions:withUpdates:withRefreshes:] () #9 0x01ba25ea in -[NSManagedObjectContext(_NSInternalChangeProcessing) _processRecentChanges:] () #10 0x01bdfb3a in -[NSManagedObjectContext processPendingChanges] () #11 0x01bd0957 in _performRunLoopAction () #12 0x01f4d252 in __CFRunLoopDoObservers () #13 0x01f4c65f in CFRunLoopRunSpecific () #14 0x01f4bc48 in CFRunLoopRunInMode () #15 0x0273878d in GSEventRunModal () #16 0x02738852 in GSEventRun () #17 0x002ba003 in UIApplicationMain () solution I managed to get to the bottom of this. I was fetching the event in question using a NSFetchedResultsController with a NSPredicate which I was releasing after I had the results. Retrieving values from the entities returned was no problem, but when I tried to update any of them it gave the error above. It should not have been released. oustanding part of my question What is a good way to create this sub list from a list of existing items in terms of a core data model. I don't believe its any of the ways I tried here. I need to show/edit it in another table view. Perhaps there is a better way than a boolean property on each event entity? The relationship idea above doesn't seem to work here (even though I can now create it). Cheers.

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• What does the `forall` keyword in Haskell/GHC do?

  - by JUST MY correct OPINION

  I've been banging my head on this one for (quite literally) years now. I'm beginning to kinda/sorta understand how the foreach keyword is used in so-called "existential types" like this: data ShowBox = forall s. Show s => SB s (This despite the confusingly-worded explanations of it in the fragments found all around the web.) This is only a subset, however, of how foreach is used and I simply cannot wrap my mind around its use in things like this: runST :: forall a. (forall s. ST s a) -> a Or explaining why these are different: foo :: (forall a. a -> a) -> (Char,Bool) bar :: forall a. ((a -> a) -> (Char, Bool)) Or the whole RankNTypes stuff that breaks my brain when "explained" in a way that makes me want to do that Samuel L. Jackson thing from Pulp Fiction. (Don't follow that link if you're easily offended by strong language.) The problem, really, is that I'm a dullard. I can't fathom the chicken scratchings (some call them "formulae") of the elite mathematicians that created this language seeing as my university years are over two decades behind me and I never actually had to put what I learnt into use in practice. I also tend to prefer clear, jargon-free English rather than the kinds of language which are normal in academic environments. Most of the explanations I attempt to read on this (the ones I can find through search engines) have these problems: They're incomplete. They explain one part of the use of this keyword (like "existential types") which makes me feel happy until I read code that uses it in a completely different way (like runST, foo and bar above). They're densely packed with assumptions that I've read the latest in whatever branch of discrete math, category theory or abstract algebra is popular this week. (If I never read the words "consult the paper whatever for details of implementation" again, it will be too soon.) They're written in ways that frequently turn even simple concepts into tortuously twisted and fractured grammar and semantics. (I suspect that the last two items are the biggest problem. I wouldn't know, though, since I'm too much a dullard to comprehend them.) It's been asked why Haskell never really caught on in industry. I suspect, in my own humble, unintelligent way, that my experience in figuring out one stupid little keyword -- a keyword that is increasingly ubiquitous in the libraries being written these days -- are also part of the answer to that question. It's hard for a language to catch on when even its individual keywords cause years-long quests to comprehend. Years-long quests which end in failure. So... On to the actual question. Can anybody completely explain the foreach keyword in clear, plain English (or, if it exists somewhere, point to such a clear explanation which I've missed) that doesn't assume I'm a mathematician steeped in the jargon?

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• Java Socket Connection is flooding network OR resulting in high ping

  - by user1461100

  i have a little problem with my java socket code. I'm writing an android client application which is sending data to a java multithreaded socket server on my pc through direct(!) wireless connection. It works fine but i want to improve it for mobile applications as it is very power consuming by now. When i remove two special lines in my code, the cpu usage of my mobile device (htc one x) is totally okay but then my connection seems to have high ping rates or something like that... Here is a server code snippet where i receive the clients data: while(true) { try { .... Object obj = in.readObject(); if(obj != null) { Class clazz = obj.getClass(); String className = clazz.getName(); if(className.equals("java.lang.String")) { String cmd = (String)obj; if(cmd.equals("dc")) { System.out.println("Client "+id+" disconnected!"); Server.connectedClients[id-1] = false; break; } if(cmd.substring(0,1).equals("!")) { robot.keyRelease(PlayerEnum.getKey(cmd,id)); } else { robot.keyPress(PlayerEnum.getKey(cmd,id)); } } } } catch .... Heres the client part, where i send my data in a while loop: private void networking() { try { if(client != null) { .... out.writeObject(sendQueue.poll()); .... } } catch .... when i write it this why, i send data everytime the while loop gets executed.. when sendQueue is empty, a null "Object" will be send. this results in "high" network traffic and in "high" cpu usage. BUT: all send comments are received nearly immediately. when i change the code to following: while(true) ... if(sendQueue.peek() != null) { out.writeObject(sendQueue.poll()); } ... the cpu usage is totally okay but i'm getting some laggs.. the commands do not arrive fast enough.. as i said, it works fine (besides cpu usage) if i'm sending data(with that null objects) every while execution. but i'm sure that this is very rough coding style because i'm kind of flooding the network. any hints? what am i doing wrong?? Thanks for your Help! Sincerly yours, maaft

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• Unit testing authorization in a Pylons app fails; cookies aren't been correctly set or recorded

  - by Ian Stevens

  I'm having an issue running unit tests for authorization in a Pylons app. It appears as though certain cookies set in the test case may not be correctly written or parsed. Cookies work fine when hitting the app with a browser. Here is my test case inside a paste-generated TestController: def test_good_login(self): r = self.app.post('/dologin', params={'login': self.user['username'], 'password': self.password}) r = r.follow() # Should only be one redirect to root assert 'http://localhost/' == r.request.url assert 'Dashboard' in r This is supposed to test that a login of an existing account forwards the user to the dashboard page. Instead, what happens is that the user is redirected back to the login. The first POST works, sets the user in the session and returns cookies. Although those cookies are sent in the follow request, they don't seem to be correctly parsed. I start by setting a breakpoint at the beginning of the above method and see what the login response returns: > nosetests --pdb --pdb-failure -s foo.tests.functional.test_account:TestMainController.test_good_login Running setup_config() from foo.websetup > /Users/istevens/dev/foo/foo/tests/functional/test_account.py(33)test_good_login() -> r = self.app.post('/dologin', params={'login': self.user['username'], 'password': self.password}) (Pdb) n > /Users/istevens/dev/foo/foo/tests/functional/test_account.py(34)test_good_login() -> r = r.follow() # Should only be one redirect to root (Pdb) p r.cookies_set {'auth_tkt': '"4c898eb72f7ad38551eb11e1936303374bd871934bd871833d19ad8a79000000!"'} (Pdb) p r.request.environ['REMOTE_USER'] '4bd871833d19ad8a79000000' (Pdb) p r.headers['Location'] 'http://localhost/?__logins=0' A session appears to be created and a cookie sent back. The browser is redirected to the root, not the login, which also indicates a successful login. If I step past the follow(), I get: > /Users/istevens/dev/foo/foo/tests/functional/test_account.py(35)test_good_login() -> assert 'http://localhost/' == r.request.url (Pdb) p r.request.headers {'Host': 'localhost:80', 'Cookie': 'auth_tkt=""\\"4c898eb72f7ad38551eb11e1936303374bd871934bd871833d19ad8a79000000!\\"""; '} (Pdb) p r.request.environ['REMOTE_USER'] *** KeyError: KeyError('REMOTE_USER',) (Pdb) p r.request.environ['HTTP_COOKIE'] 'auth_tkt=""\\"4c898eb72f7ad38551eb11e1936303374bd871934bd871833d19ad8a79000000!\\"""; ' (Pdb) p r.request.cookies {'auth_tkt': ''} (Pdb) p r <302 Found text/html location: http://localhost/login?__logins=1&came_from=http%3A%2F%2Flocalhost%2F body='302 Found...y. '/149> This indicates to me that the cookie was passed in on the request, although with dubious escaping. The environ appears to be without the session created on the prior request. The cookie has been copied to the environ from the headers, but the cookies in the request seems incorrectly set. Lastly, the user is redirected to the login page, indicating that the user isn't logged in. Authorization in the app is done via repoze.who and repoze.who.plugins.ldap with repoze.who_friendlyform performing the challenge. I'm using the stock tests.TestController created by paste: class TestController(TestCase): def __init__(self, *args, **kwargs): if pylons.test.pylonsapp: wsgiapp = pylons.test.pylonsapp else: wsgiapp = loadapp('config:%s' % config['__file__']) self.app = TestApp(wsgiapp) url._push_object(URLGenerator(config['routes.map'], environ)) TestCase.__init__(self, *args, **kwargs) That's a webtest.TestApp, by the way. The encoding of the cookie is done in webtest.TestApp using Cookie: >>> from Cookie import _quote >>> _quote('"84533cf9f661f97239208fb844a09a6d4bd8552d4bd8550c3d19ad8339000000!"') '"\\"84533cf9f661f97239208fb844a09a6d4bd8552d4bd8550c3d19ad8339000000!\\""' I trust that that's correct. My guess is that something on the response side is incorrectly parsing the cookie data into cookies in the server-side request. But what? Any ideas?

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• Lockless queue implementation ends up having a loop under stress

  - by Fozi

  I have lockless queues written in C in form of a linked list that contains requests from several threads posted to and handled in a single thread. After a few hours of stress I end up having the last request's next pointer pointing to itself, which creates an endless loop and locks up the handling thread. The application runs (and fails) on both Linux and Windows. I'm debugging on Windows, where my COMPARE_EXCHANGE_PTR maps to InterlockedCompareExchangePointer. This is the code that pushes a request to the head of the list, and is called from several threads: void push_request(struct request * volatile * root, struct request * request) { assert(request); do { request->next = *root; } while(COMPARE_EXCHANGE_PTR(root, request, request->next) != request->next); } This is the code that gets a request from the end of the list, and is only called by a single thread that is handling them: struct request * pop_request(struct request * volatile * root) { struct request * volatile * p; struct request * request; do { p = root; while(*p && (*p)->next) p = &(*p)->next; // <- loops here request = *p; } while(COMPARE_EXCHANGE_PTR(p, NULL, request) != request); assert(request->next == NULL); return request; } Note that I'm not using a tail pointer because I wanted to avoid the complication of having to deal with the tail pointer in push_request. However I suspect that the problem might be in the way I find the end of the list. There are several places that push a request into the queue, but they all look generaly like this: // device->requests is defined as struct request * volatile requests; struct request * request = malloc(sizeof(struct request)); if(request) { // fill out request fields push_request(&device->requests, request); sem_post(device->request_sem); } The code that handles the request is doing more than that, but in essence does this in a loop: if(sem_wait_timeout(device->request_sem, timeout) == sem_success) { struct request * request = pop_request(&device->requests); // handle request free(request); } I also just added a function that is checking the list for duplicates before and after each operation, but I'm afraid that this check will change the timing so that I will never encounter the point where it fails. (I'm waiting for it to break as I'm writing this.) When I break the hanging program the handler thread loops in pop_request at the marked position. I have a valid list of one or more requests and the last one's next pointer points to itself. The request queues are usually short, I've never seen more then 10, and only 1 and 3 the two times I could take a look at this failure in the debugger. I thought this through as much as I could and I came to the conclusion that I should never be able to end up with a loop in my list unless I push the same request twice. I'm quite sure that this never happens. I'm also fairly sure (although not completely) that it's not the ABA problem. I know that I might pop more than one request at the same time, but I believe this is irrelevant here, and I've never seen it happening. (I'll fix this as well) I thought long and hard about how I can break my function, but I don't see a way to end up with a loop. So the question is: Can someone see a way how this can break? Can someone prove that this can not? Eventually I will solve this (maybe by using a tail pointer or some other solution - locking would be a problem because the threads that post should not be locked, I do have a RW lock at hand though) but I would like to make sure that changing the list actually solves my problem (as opposed to makes it just less likely because of different timing).

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• How to generalize a method call in Java (to avoid code duplication)

  - by dln385

  I have a process that needs to call a method and return its value. However, there are several different methods that this process may need to call, depending on the situation. If I could pass the method and its arguments to the process (like in Python), then this would be no problem. However, I don't know of any way to do this in Java. Here's a concrete example. (This example uses Apache ZooKeeper, but you don't need to know anything about ZooKeeper to understand the example.) The ZooKeeper object has several methods that will fail if the network goes down. In this case, I always want to retry the method. To make this easy, I made a "BetterZooKeeper" class that inherits the ZooKeeper class, and all of its methods automatically retry on failure. This is what the code looked like: public class BetterZooKeeper extends ZooKeeper { private void waitForReconnect() { // logic } @Override public Stat exists(String path, Watcher watcher) { while (true) { try { return super.exists(path, watcher); } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } @Override public byte[] getData(String path, boolean watch, Stat stat) { while (true) { try { return super.getData(path, watch, stat); } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } @Override public void delete(String path, int version) { while (true) { try { super.delete(path, version); return; } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } } (In the actual program there is much more logic and many more methods that I took out of the example for simplicity.) We can see that I'm using the same retry logic, but the arguments, method call, and return type are all different for each of the methods. Here's what I did to eliminate the duplication of code: public class BetterZooKeeper extends ZooKeeper { private void waitForReconnect() { // logic } @Override public Stat exists(final String path, final Watcher watcher) { return new RetryableZooKeeperAction<Stat>() { @Override public Stat action() { return BetterZooKeeper.super.exists(path, watcher); } }.run(); } @Override public byte[] getData(final String path, final boolean watch, final Stat stat) { return new RetryableZooKeeperAction<byte[]>() { @Override public byte[] action() { return BetterZooKeeper.super.getData(path, watch, stat); } }.run(); } @Override public void delete(final String path, final int version) { new RetryableZooKeeperAction<Object>() { @Override public Object action() { BetterZooKeeper.super.delete(path, version); return null; } }.run(); return; } private abstract class RetryableZooKeeperAction<T> { public abstract T action(); public final T run() { while (true) { try { return action(); } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } } } The RetryableZooKeeperAction is parameterized with the return type of the function. The run() method holds the retry logic, and the action() method is a placeholder for whichever ZooKeeper method needs to be run. Each of the public methods of BetterZooKeeper instantiates an anonymous inner class that is a subclass of the RetryableZooKeeperAction inner class, and it overrides the action() method. The local variables are (strangely enough) implicitly passed to the action() method, which is possible because they are final. In the end, this approach does work and it does eliminate the duplication of the retry logic. However, it has two major drawbacks: (1) it creates a new object every time a method is called, and (2) it's ugly and hardly readable. Also I had to workaround the 'delete' method which has a void return value. So, here is my question: is there a better way to do this in Java? This can't be a totally uncommon task, and other languages (like Python) make it easier by allowing methods to be passed. I suspect there might be a way to do this through reflection, but I haven't been able to wrap my head around it.

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• What broke in this Javascript 1.2 snippet?

  - by Rob Kelley

  A friend has pointed me to his old website and says "the submit form just stopped working a while ago. I'm sure it's something simple." The form asks a child for a certain word from a book, and based on the answer, it should redirect the child to a success page or a failure page. It's using Javascript 1.2, circa 2001. You can see this form in in-action at: http://www.secrethidingplaces.com/login1.html Any idea why it's failing? The HTML does this: <script src="password.js" type="text/javascript" language="JavaScript1.2"> </script> <script type="text/javascript" language="JavaScript1.2"> <!-- function showRightPage () { return window.location.href = "extra.html" ; } function showWrongPage () { return window.location.href = "sorry2.html" ; } //--> </script> and then this: document.write ( '<form name="questionForm" action="javascript:checkAnswer()" method="post">' ) ; ... document.write ( '<input type="text" name="userAnswer" value="" size="90">' ) ; document.write ( '<INPUT TYPE="image" NAME="submit" SRC="stock/btn_send.gif" width="121" height="41" BORDER="0" ALT="submit">' ) ; document.write ( '\</p>' ) ; document.write ( '\</form>' ) ; I'm assuming there's something ugly in CheckAnswer from ./password.js . I can hack the form to bypass that javascript and go straight to the success page: document.write ( '<form name="questionForm" action="extra.html" method="post">' ) ; but I'd like to help my friend get his kids site working again. The CheckAnswer function is below. Is something going wrong in here? function checkAnswer () { currentAnswer = answersArray [ choiceNumber ] ; if (agt.indexOf("msie") != -1) { rawAnswer = document.questionForm.userAnswer.value ; } else { rawAnswer = document.callThis.document.questionForm.userAnswer.value ; } lcAnswer = rawAnswer.toLowerCase ( ) ; includedAnswer = lcAnswer.indexOf ( "currentAnswer" ) ; zadaAnswer = lcAnswer.indexOf ( "zada" ) ; brendanAnswer = lcAnswer.indexOf ( "brendan" ) ; nineAnswer = lcAnswer.indexOf ( "nine" ) ; thirtyAnswer = lcAnswer.indexOf ( "thirty" ) ; if ( choiceNumber == 0 ) { if ( includedAnswer == -1 && zadaAnswer == -1 && brendanAnswer == -1 ) { checked = "wrong" ; } } if ( choiceNumber == 8 ) { if ( includedAnswer == -1 && zadaAnswer == -1 && nineAnswer == -1 ) { checked = "wrong" ; } } if ( choiceNumber == 16 ) { if ( includedAnswer == -1 && zadaAnswer == -1 && thirtyAnswer == -1 ) { checked = "wrong" ; } } if ( choiceNumber != 0 && choiceNumber != 8 && choiceNumber != 16 ) { if ( includedAnswer == -1 && zadaAnswer == -1 ) { checked = "wrong" ; } } if ( checked == "wrong" ) { showWrongPage () ; } else { showRightPage () ; } } Thanks!

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• "didChangeSection:" NSfetchedResultsController delegate method not being called

  - by robenk

  I have a standard split view controller, with a detail view and a table view. Pressing a button in the detail view can cause the an object to change its placement in the table view's ordering. This works fine, as long as the resulting ordering change doesn't result in a section being added or removed. I.e. an object can change it's ordering in a section or switch from one section to another. Those ordering changes work correctly without problems. But, if the object tries to move to a section that doesn't exist yet, or is the last object to leave a section (therefore requiring the section its leaving to be removed), then the application crashes. NSFetchedResultsControllerDelegate has methods to handle sections being added and removed that should be called in those cases. But those delegate methods aren't being called for some reason. The code in question, is boilerplate: - (void)controllerWillChangeContent:(NSFetchedResultsController *)controller { NSLog(@"willChangeContent"); [self.tableView beginUpdates]; } - (void)controller:(NSFetchedResultsController *)controller didChangeSection:(id <NSFetchedResultsSectionInfo>)sectionInfo atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type { NSLog(@"didChangeSection"); switch(type) { case NSFetchedResultsChangeInsert: [self.tableView insertSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade]; break; case NSFetchedResultsChangeDelete: [self.tableView deleteSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade]; break; } } - (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type newIndexPath:(NSIndexPath *)newIndexPath { NSLog(@"didChangeObject"); UITableView *tableView = self.tableView; switch(type) { case NSFetchedResultsChangeInsert: [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade]; break; case NSFetchedResultsChangeDelete: [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade]; break; case NSFetchedResultsChangeUpdate: [self configureCell:[tableView cellForRowAtIndexPath:indexPath] atIndexPath:indexPath]; break; case NSFetchedResultsChangeMove: [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade]; [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath]withRowAnimation:UITableViewRowAnimationFade]; break; } } - (void)controllerDidChangeContent:(NSFetchedResultsController *)controller { NSLog(@"didChangeContent"); [self.tableView endUpdates]; [detailViewController.reminderView update]; } Starting the application, and then causing the last object to leave a section results in the following output: 2011-01-08 23:40:18.910 Reminders[54647:207] willChangeContent 2011-01-08 23:40:18.912 Reminders[54647:207] didChangeObject 2011-01-08 23:40:18.914 Reminders[54647:207] didChangeContent 2011-01-08 23:40:18.915 Reminders[54647:207] *** Assertion failure in -[UITableView _endCellAnimationsWithContext:], /SourceCache/UIKit_Sim/UIKit-1145.66/UITableView.m:825 2011-01-08 23:40:18.917 Reminders[54647:207] Serious application error. Exception was caught during Core Data change processing: Invalid update: invalid number of sections. The number of sections contained in the table view after the update (5) must be equal to the number of sections contained in the table view before the update (6), plus or minus the number of sections inserted or deleted (0 inserted, 0 deleted). with userInfo (null) As you can see, "willChangeContent", "didChangeObject" (moving the object in question), and "didChangeContent" were all called properly. Based on the Apple's NSFetchedResultsControllerDelegate documentation "didChangeSection" should have been called before "didChangeObject", which would have prevented the exception causing the crash. So I guess the question is how do I assure that didChangeSection gets called? Thanks in advance for any help!

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• Header Guard Issues - Getting Swallowed Alive

  - by gjnave

  I'm totally at wit's end: I can't figure out how my dependency issues. I've read countless posts and blogs and reworked my code so many times that I can't even remember what almost worked and what didnt. I continually get not only redefinition errors, but class not defined errors. I rework the header guards and remove some errors simply to find others. I somehow got everything down to one error but then even that got broke while trying to fix it. Would you please help me figure out the problem? card.cpp #include <iostream> #include <cctype> #include "card.h" using namespace std; // ====DECL====== Card::Card() { abilities = 0; flavorText = 0; keywords = 0; artifact = 0; classType = new char[strlen("Card") + 1]; classType = "Card"; } Card::~Card (){ delete name; delete abilities; delete flavorText; artifact = NULL; } // ------------ Card::Card(const Card & to_copy) { name = new char[strlen(to_copy.name) +1]; // creating dynamic array strcpy(to_copy.name, name); type = to_copy.type; color = to_copy.color; manaCost = to_copy.manaCost; abilities = new char[strlen(to_copy.abilities) +1]; strcpy(abilities, to_copy.abilities); flavorText = new char[strlen(to_copy.flavorText) +1]; strcpy(flavorText, to_copy.flavorText); keywords = new char[strlen(to_copy.keywords) +1]; strcpy(keywords, to_copy.keywords); inPlay = to_copy.inPlay; tapped = to_copy.tapped; enchanted = to_copy.enchanted; cursed = to_copy.cursed; if (to_copy.type != ARTIFACT) artifact = to_copy.artifact; } // ====DECL===== int Card::equipArtifact(Artifact* to_equip){ artifact = to_equip; } Artifact * Card::unequipArtifact(Card * unequip_from){ Artifact * to_remove = artifact; artifact = NULL; return to_remove; // put card in hand or in graveyard } int Card::enchant( Card * to_enchant){ to_enchant->enchanted = true; cout << "enchanted" << endl; } int Card::disenchant( Card * to_disenchant){ to_disenchant->enchanted = false; cout << "Enchantment Removed" << endl; } // ========DECL===== Spell::Spell() { currPower = basePower; currToughness = baseToughness; classType = new char[strlen("Spell") + 1]; classType = "Spell"; } Spell::~Spell(){} // --------------- Spell::Spell(const Spell & to_copy){ currPower = to_copy.currPower; basePower = to_copy.basePower; currToughness = to_copy.currToughness; baseToughness = to_copy.baseToughness; } // ========= int Spell::attack( Spell *& blocker ){ blocker->currToughness -= currPower; currToughness -= blocker->currToughness; } //========== int Spell::counter (Spell *& to_counter){ cout << to_counter->name << " was countered by " << name << endl; } // ============ int Spell::heal (Spell *& to_heal, int amountOfHealth){ to_heal->currToughness += amountOfHealth; } // ------- Creature::Creature(){ summoningSick = true; } // =====DECL====== Land::Land(){ color = NON; classType = new char[strlen("Land") + 1]; classType = "Land"; } // ------ int Land::generateMana(int mana){ // ... // } card.h #ifndef CARD_H #define CARD_H #include <cctype> #include <iostream> #include "conception.h" class Artifact; class Spell; class Card : public Conception { public: Card(); Card(const Card &); ~Card(); protected: char* name; enum CardType { INSTANT, CREATURE, LAND, ENCHANTMENT, ARTIFACT, PLANESWALKER}; enum CardColor { WHITE, BLUE, BLACK, RED, GREEN, NON }; CardType type; CardColor color; int manaCost; char* abilities; char* flavorText; char* keywords; bool inPlay; bool tapped; bool cursed; bool enchanted; Artifact* artifact; virtual int enchant( Card * ); virtual int disenchant (Card * ); virtual int equipArtifact( Artifact* ); virtual Artifact* unequipArtifact(Card * ); }; // ------------ class Spell: public Card { public: Spell(); ~Spell(); Spell(const Spell &); protected: virtual int heal( Spell *&, int ); virtual int attack( Spell *& ); virtual int counter( Spell*& ); int currToughness; int baseToughness; int currPower; int basePower; }; class Land: public Card { public: Land(); ~Land(); protected: virtual int generateMana(int); }; class Forest: public Land { public: Forest(); ~Forest(); protected: int generateMana(); }; class Creature: public Spell { public: Creature(); ~Creature(); protected: bool summoningSick; }; class Sorcery: public Spell { public: Sorcery(); ~Sorcery(); protected: }; #endif conception.h -- this is an "uber class" from which everything derives class Conception{ public: Conception(); ~Conception(); protected: char* classType; }; conception.cpp Conception::Conception{ Conception(){ classType = new char[11]; char = "Conception"; } game.cpp -- this is an incomplete class as of this code #include <iostream> #include <cctype> #include "game.h" #include "player.h" Battlefield::Battlefield(){ card = 0; } Battlefield::~Battlefield(){ delete card; } Battlefield::Battlefield(const Battlefield & to_copy){ } // =========== /* class Game(){ public: Game(); ~Game(); protected: Player** player; // for multiple players Battlefield* root; // for battlefield getPlayerMove(); // ask player what to do addToBattlefield(); removeFromBattlefield(); sendAttack(); } */ #endif game.h #ifndef GAME_H #define GAME_H #include "list.h" class CardList(); class Battlefield : CardList{ public: Battlefield(); ~Battlefield(); protected: Card* card; // make an array }; class Game : Conception{ public: Game(); ~Game(); protected: Player** player; // for multiple players Battlefield* root; // for battlefield getPlayerMove(); // ask player what to do addToBattlefield(); removeFromBattlefield(); sendAttack(); Battlefield* field; }; list.cpp #include <iostream> #include <cctype> #include "list.h" // ========== LinkedList::LinkedList(){ root = new Node; classType = new char[strlen("LinkedList") + 1]; classType = "LinkedList"; }; LinkedList::~LinkedList(){ delete root; } LinkedList::LinkedList(const LinkedList & obj) { // code to copy } // --------- // ========= int LinkedList::delete_all(Node* root){ if (root = 0) return 0; delete_all(root->next); root = 0; } int LinkedList::add( Conception*& is){ if (root == 0){ root = new Node; root->next = 0; } else { Node * curr = root; root = new Node; root->next=curr; root->it = is; } } int LinkedList::remove(Node * root, Node * prev, Conception* is){ if (root = 0) return -1; if (root->it == is){ root->next = root->next; return 0; } remove(root->next, root, is); return 0; } Conception* LinkedList::find(Node*& root, const Conception* is, Conception* holder = NULL) { if (root==0) return NULL; if (root->it == is){ return root-> it; } holder = find(root->next, is); return holder; } Node* LinkedList::goForward(Node * root){ if (root==0) return root; if (root->next == 0) return root; else return root->next; } // ============ Node* LinkedList::goBackward(Node * root){ root = root->prev; } list.h #ifndef LIST_H #define LIST_H #include <iostream> #include "conception.h" class Node : public Conception { public: Node() : next(0), prev(0), it(0) { it = 0; classType = new char[strlen("Node") + 1]; classType = "Node"; }; ~Node(){ delete it; delete next; delete prev; } Node* next; Node* prev; Conception* it; // generic object }; // ---------------------- class LinkedList : public Conception { public: LinkedList(); ~LinkedList(); LinkedList(const LinkedList&); friend bool operator== (Conception& thing_1, Conception& thing_2 ); protected: virtual int delete_all(Node*); virtual int add( Conception*& ); // virtual Conception* find(Node *&, const Conception*, Conception* ); // virtual int remove( Node *, Node *, Conception* ); // removes question with keyword int display_all(node*& ); virtual Node* goForward(Node *); virtual Node* goBackward(Node *); Node* root; // write copy constrcutor }; // ============= class CircularLinkedList : public LinkedList { public: // CircularLinkedList(); // ~CircularLinkedList(); // CircularLinkedList(const CircularLinkedList &); }; class DoubleLinkedList : public LinkedList { public: // DoubleLinkedList(); // ~DoubleLinkedList(); // DoubleLinkedList(const DoubleLinkedList &); protected: }; // END OF LIST Hierarchy #endif player.cpp #include <iostream> #include "player.h" #include "list.h" using namespace std; Library::Library(){ root = 0; } Library::~Library(){ delete card; } // ====DECL========= Player::~Player(){ delete fname; delete lname; delete deck; } Wizard::~Wizard(){ delete mana; delete rootL; delete rootH; } // =====Player====== void Player::changeName(const char[] first, const char[] last){ char* backup1 = new char[strlen(fname) + 1]; strcpy(backup1, fname); char* backup2 = new char[strlen(lname) + 1]; strcpy(backup1, lname); if (first != NULL){ fname = new char[strlen(first) +1]; strcpy(fname, first); } if (last != NULL){ lname = new char[strlen(last) +1]; strcpy(lname, last); } return 0; } // ========== void Player::seeStats(Stats*& to_put){ to_put->wins = stats->wins; to_put->losses = stats->losses; to_put->winRatio = stats->winRatio; } // ---------- void Player::displayDeck(const LinkedList* deck){ } // ================ void CardList::findCard(Node* root, int id, NodeCard*& is){ if (root == NULL) return; if (root->it.id == id){ copyCard(root->it, is); return; } else findCard(root->next, id, is); } // -------- void CardList::deleteAll(Node* root){ if (root == NULL) return; deleteAll(root->next); root->next = NULL; } // --------- void CardList::removeCard(Node* root, int id){ if (root == NULL) return; if (root->id = id){ root->prev->next = root->next; // the prev link of root, looks back to next of prev node, and sets to where root next is pointing } return; } // --------- void CardList::addCard(Card* to_add){ if (!root){ root = new Node; root->next = NULL; root->prev = NULL; root->it = &to_add; return; } else { Node* original = root; root = new Node; root->next = original; root->prev = NULL; original->prev = root; } } // ----------- void CardList::displayAll(Node*& root){ if (root == NULL) return; cout << "Card Name: " << root->it.cardName; cout << " || Type: " << root->it.type << endl; cout << " --------------- " << endl; if (root->classType == "Spell"){ cout << "Base Power: " << root->it.basePower; cout << " || Current Power: " << root->it.currPower << endl; cout << "Base Toughness: " << root->it.baseToughness; cout << " || Current Toughness: " << root->it.currToughness << endl; } cout << "Card Type: " << root->it.currPower; cout << " || Card Color: " << root->it.color << endl; cout << "Mana Cost" << root->it.manaCost << endl; cout << "Keywords: " << root->it.keywords << endl; cout << "Flavor Text: " << root->it.flavorText << endl; cout << " ----- Class Type: " << root->it.classType << " || ID: " << root->it.id << " ----- " << endl; cout << " ******************************************" << endl; cout << endl; // ------- void CardList::copyCard(const Card& to_get, Card& put_to){ put_to.type = to_get.type; put_to.color = to_get.color; put_to.manaCost = to_get.manaCost; put_to.inPlay = to_get.inPlay; put_to.tapped = to_get.tapped; put_to.class = to_get.class; put_to.id = to_get.id; put_to.enchanted = to_get.enchanted; put_to.artifact = to_get.artifact; put_to.class = to_get.class; put.to.abilities = new char[strlen(to_get.abilities) +1]; strcpy(put_to.abilities, to_get.abilities); put.to.keywords = new char[strlen(to_get.keywords) +1]; strcpy(put_to.keywords, to_get.keywords); put.to.flavorText = new char[strlen(to_get.flavorText) +1]; strcpy(put_to.flavorText, to_get.flavorText); if (to_get.class = "Spell"){ put_to.baseToughness = to_get.baseToughness; put_to.basePower = to_get.basePower; put_to.currToughness = to_get.currToughness; put_to.currPower = to_get.currPower; } } // ---------- player.h #ifndef player.h #define player.h #include "list.h" // ============ class CardList() : public LinkedList(){ public: CardList(); ~CardList(); protected: virtual void findCard(Card&); virtual void addCard(Card* ); virtual void removeCard(Node* root, int id); virtual void deleteAll(); virtual void displayAll(); virtual void copyCard(const Conception*, Node*&); Node* root; } // --------- class Library() : public CardList(){ public: Library(); ~Library(); protected: Card* card; int numCards; findCard(Card&); // get Card and fill empty template } // ----------- class Deck() : public CardList(){ public: Deck(); ~Deck(); protected: enum deckColor { WHITE, BLUE, BLACK, RED, GREEN, MIXED }; char* deckName; } // =============== class Mana(int amount) : public Conception { public: Mana() : displayTotal(0), classType(0) { displayTotal = 0; classType = new char[strlen("Mana") + 1]; classType = "Mana"; }; protected: int accrued; void add(); void remove(); int displayTotal(); } inline Mana::add(){ accrued += 1; } inline Mana::remove(){ accrued -= 1; } inline Mana::displayTotal(){ return accrued; } // ================ class Stats() : public Conception { public: friend class Player; friend class Game; Stats() : wins(0), losses(0), winRatio(0) { wins = 0; losses = 0; if ( (wins + losses != 0) winRatio = wins / (wins + losses); else winRatio = 0; classType = new char[strlen("Stats") + 1]; classType = "Stats"; } protected: int wins; int losses; float winRatio; void int getStats(Stats*& ); } // ================== class Player() : public Conception{ public: Player() : wins(0), losses(0), winRatio(0) { fname = NULL; lname = NULL; stats = NULL; CardList = NULL; classType = new char[strlen("Player") + 1]; classType = "Player"; }; ~Player(); Player(const Player & obj); protected: // member variables char* fname; char* lname; Stats stats; // holds previous game statistics CardList* deck[]; // hold multiple decks that player might use - put ll in this private: // member functions void changeName(const char[], const char[]); void shuffleDeck(int); void seeStats(Stats*& ); void displayDeck(int); chooseDeck(); } // -------------------- class Wizard(Card) : public Player(){ public: Wizard() : { mana = NULL; rootL = NULL; rootH = NULL}; ~Wizard(); protected: playCard(const Card &); removeCard(Card &); attackWithCard(Card &); enchantWithCard(Card &); disenchantWithCard(Card &); healWithCard(Card &); equipWithCard(Card &); Mana* mana[]; Library* rootL; // Library Library* rootH; // Hand } #endif

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• xmlpullparser(), whats wrong with my code?

  - by Avinazz

  I am expecting output to be an array list filled with all items as "thought" but instead, every time i add a value into arraylist, the previous value in list also gets update with new, hence resulting in duplicates. This behaviour goes on till end. Even though i have achieved the result by changing the approach, failure of my previous approach still bothers me. Any help or pointer will be really appreciated. Below is xml snippet: <Thoughts> <country> <name>India</name> <item> <itemId>1</itemId> <itemDetailImage>detail.png</itemDetailImage> <itemImage>image1.png</itemImage> <itemDesc>Item Description 1</itemDesc> <itemTitle>Item Title 1</itemTitle> </item> <item> <itemId>2</itemId> <itemDetailImage>detail2.png</itemDetailImage> <itemImage>image2.png</itemImage> <itemDesc>Item Description 2</itemDesc> <itemTitle>Item Title 2</itemTitle> </item> <item> <itemId>3</itemId> <itemDetailImage>detail3.png</itemDetailImage> <itemImage>image3.png</itemImage> <itemDesc>Item Description 3</itemDesc> <itemTitle>Item Title 3</itemTitle> </item> Below is a method for my trial and error: private void printAll() throws XmlPullParserException, IOException{ XmlPullParserFactory factory = XmlPullParserFactory.newInstance(); factory.setNamespaceAware(false); XmlPullParser parser = factory.newPullParser(); URL url = new URL("http://192.168.1.3/DefaultXML.xml"); URLConnection ucon = url.openConnection(); InputStream is = ucon.getInputStream(); parser.setInput(is, null); int eventType = parser.getEventType(); String name; while(eventType != parser.END_DOCUMENT){ if(eventType == parser.START_DOCUMENT){ Log.i(TAG,"Start document"); }else if (eventType == parser.START_TAG ) { name = parser.getName(); if(name.equalsIgnoreCase(NAME)){ this.cName = new Country(); this.cName.setName(parser.nextText()); }else if(name.equalsIgnoreCase(ITEM_DESC)){ this.thought.setItemDesc(parser.nextText()); }else if (name.equalsIgnoreCase(ITEM_ID)) { this.thought.setItemID(parser.nextText()); }else if (name.equalsIgnoreCase(ITEM_DETAIL_IMAGE)) { this.thought.setItemDetailImage(parser.nextText()); }else if (name.equalsIgnoreCase(ITEM_IMAGE)) { this.thought.setItemImage(parser.nextText()); }else if (name.equalsIgnoreCase(ITEM_TITLE)) { this.thought.setItemTitle(parser.nextText()); } }else if (eventType == parser.END_TAG) { name = parser.getName(); if(name.equalsIgnoreCase(ITEM)) { this.cName.setThought(this.thought); ctry.add(cName); this.thought = new Thought(); } } eventType = parser.next(); } //Log.i(TAG,"---" + ctry.toString()); }

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• OpenGL texture misaligned on quad

  - by user308226

  I've been having trouble with this for a while now, and I haven't gotten any solutions that work yet. Here is the problem, and the specifics: I am loading a 256x256 uncompressed TGA into a simple OpenGL program that draws a quad on the screen, but when it shows up, it is shifted about two pixels to the left, with the cropped part appearing on the right side. It has been baffling me for the longest time, people have suggested clamping and such, but somehow I think my problem is probably something really simple, but I just can't figure out what it is! Here is a screenshot comparing the TGA (left) and how it appears running in the program (right) for clarity. Also take note that there's a tiny black pixel on the upper right corner, I'm hoping that's related to the same problem. Here's the code for the loader, I'm convinced that my problem lies in the way that I'm loading the texture. Thanks in advance to anyone who can fix my problem. bool TGA::LoadUncompressedTGA(char *filename,ifstream &texturestream) { cout << "G position status:" << texturestream.tellg() << endl; texturestream.read((char*)header, sizeof(header)); //read 6 bytes into the file to get the tga header width = (GLuint)header[1] * 256 + (GLuint)header[0]; //read and calculate width and save height = (GLuint)header[3] * 256 + (GLuint)header[2]; //read and calculate height and save bpp = (GLuint)header[4]; //read bpp and save cout << bpp << endl; if((width <= 0) || (height <= 0) || ((bpp != 24) && (bpp !=32))) //check to make sure the height, width, and bpp are valid { return false; } if(bpp == 24) { type = GL_RGB; } else { type = GL_RGBA; } imagesize = ((bpp/8) * width * height); //determine size in bytes of the image cout << imagesize << endl; imagedata = new GLubyte[imagesize]; //allocate memory for our imagedata variable texturestream.read((char*)imagedata,imagesize); //read according the the size of the image and save into imagedata for(GLuint cswap = 0; cswap < (GLuint)imagesize; cswap += (bpp/8)) //loop through and reverse the tga's BGR format to RGB { imagedata[cswap] ^= imagedata[cswap+2] ^= //1st Byte XOR 3rd Byte XOR 1st Byte XOR 3rd Byte imagedata[cswap] ^= imagedata[cswap+2]; } texturestream.close(); //close ifstream because we're done with it cout << "image loaded" << endl; glGenTextures(1, &texID); // Generate OpenGL texture IDs glBindTexture(GL_TEXTURE_2D, texID); glPixelStorei(GL_UNPACK_ALIGNMENT, 1); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); glTexImage2D(GL_TEXTURE_2D, 0, type, width, height, 0, type, GL_UNSIGNED_BYTE, imagedata); delete imagedata; return true; } //Public loading function for TGA images. Opens TGA file and determines //its type, if any, then loads it and calls the appropriate function. //Returns: TRUE on success, FALSE on failure bool TGA::loadTGA(char *filename) { cout << width << endl; ifstream texturestream; texturestream.open(filename,ios::binary); texturestream.read((char*)header,sizeof(header)); //read 6 bytes into the file, its the header. //if it matches the uncompressed header's first 6 bytes, load it as uncompressed LoadUncompressedTGA(filename,texturestream); return true; }

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• How can I keep my MVC Views, models, and model binders as clean as possible?

  - by MBonig

  I'm rather new to MVC and as I'm getting into the whole framework more and more I'm finding the modelbinders are becoming tough to maintain. Let me explain... I am writing a basic CRUD-over-database app. My domain models are going to be very rich. In an attempt to keep my controllers as thin as possible I've set it up so that on Create/Edit commands the parameter for the action is a richly populated instance of my domain model. To do this I've implemented a custom model binder. As a result, though, this custom model binder is very specific to the view and the model. I've decided to just override the DefaultModelBinder that ships with MVC 2. In the case where the field being bound to my model is just a textbox (or something as simple), I just delegate to the base method. However, when I'm working with a dropdown or something more complex (the UI dictates that date and time are separate data entry fields but for the model it is one Property), I have to perform some checks and some manual data munging. The end result of this is that I have some pretty tight ties between the View and Binder. I'm architecturally fine with this but from a code maintenance standpoint, it's a nightmare. For example, my model I'm binding here is of type Log (this is the object I will get as a parameter on my Action). The "ServiceStateTime" is a property on Log. The form values of "log.ServiceStartDate" and "log.ServiceStartTime" are totally arbitrary and come from two textboxes on the form (Html.TextBox("log.ServiceStartTime",...)) protected override object GetPropertyValue(ControllerContext controllerContext, ModelBindingContext bindingContext, PropertyDescriptor propertyDescriptor, IModelBinder propertyBinder) { if (propertyDescriptor.Name == "ServiceStartTime") { string date = bindingContext.ValueProvider.GetValue("log.ServiceStartDate").ConvertTo(typeof (string)) as string; string time = bindingContext.ValueProvider.GetValue("log.ServiceStartTime").ConvertTo(typeof (string)) as string; DateTime dateTime = DateTime.Parse(date + " " + time); return dateTime; } if (propertyDescriptor.Name == "ServiceEndTime") { string date = bindingContext.ValueProvider.GetValue("log.ServiceEndDate").ConvertTo(typeof(string)) as string; string time = bindingContext.ValueProvider.GetValue("log.ServiceEndTime").ConvertTo(typeof(string)) as string; DateTime dateTime = DateTime.Parse(date + " " + time); return dateTime; } The Log.ServiceEndTime is a similar field. This doesn't feel very DRY to me. First, if I refactor the ServiceStartTime or ServiceEndTime into different field names, the text strings may get missed (although my refactoring tool of choice, R#, is pretty good at this sort of thing, it wouldn't cause a build-time failure and would only get caught by manual testing). Second, if I decided to arbitrarily change the descriptors "log.ServiceStartDate" and "log.ServiceStartTime", I would run into the same problem. To me, runtime silent errors are the worst kind of error out there. So, I see a couple of options to help here and would love to get some input from people who have come across some of these issues: Refactor any text strings in common between the view and model binders out into const strings attached to the ViewModel object I pass from controller to the aspx/ascx view. This pollutes the ViewModel object, though. Provide unit tests around all of the interactions. I'm a big proponent of unit tests and haven't started fleshing this option out but I've got a gut feeling that it won't save me from foot-shootings. If it matters, the Log and other entities in the system are persisted to the database using Fluent NHibernate. I really want to keep my controllers as thin as possible. So, any suggestions here are greatly welcomed! Thanks

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• Templated function with two type parameters fails compile when used with an error-checking macro

  - by SirPentor

  Because someone in our group hates exceptions (let's not discuss that here), we tend to use error-checking macros in our C++ projects. I have encountered an odd compilation failure when using a templated function with two type parameters. There are a few errors (below), but I think the root cause is a warning: warning C4002: too many actual parameters for macro 'BOOL_CHECK_BOOL_RETURN' Probably best explained in code: #include "stdafx.h" template<class A, class B> bool DoubleTemplated(B & value) { return true; } template<class A> bool SingleTemplated(A & value) { return true; } bool NotTemplated(bool & value) { return true; } #define BOOL_CHECK_BOOL_RETURN(expr) \ do \ { \ bool __b = (expr); \ if (!__b) \ { \ return false; \ } \ } while (false) \ bool call() { bool thing = true; // BOOL_CHECK_BOOL_RETURN(DoubleTemplated<int, bool>(thing)); // Above line doesn't compile. BOOL_CHECK_BOOL_RETURN((DoubleTemplated<int, bool>(thing))); // Above line compiles just fine. bool temp = DoubleTemplated<int, bool>(thing); // Above line compiles just fine. BOOL_CHECK_BOOL_RETURN(SingleTemplated<bool>(thing)); BOOL_CHECK_BOOL_RETURN(NotTemplated(thing)); return true; } int _tmain(int argc, _TCHAR* argv[]) { call(); return 0; } Here are the errors, when the offending line is not commented out: 1>------ Build started: Project: test, Configuration: Debug Win32 ------ 1>Compiling... 1>test.cpp 1>c:\junk\temp\test\test\test.cpp(38) : warning C4002: too many actual parameters for macro 'BOOL_CHECK_BOOL_RETURN' 1>c:\junk\temp\test\test\test.cpp(38) : error C2143: syntax error : missing ',' before ')' 1>c:\junk\temp\test\test\test.cpp(38) : error C2143: syntax error : missing ';' before '{' 1>c:\junk\temp\test\test\test.cpp(41) : error C2143: syntax error : missing ';' before '{' 1>c:\junk\temp\test\test\test.cpp(48) : error C2143: syntax error : missing ';' before '{' 1>c:\junk\temp\test\test\test.cpp(49) : error C2143: syntax error : missing ';' before '{' 1>c:\junk\temp\test\test\test.cpp(52) : error C2143: syntax error : missing ';' before '}' 1>c:\junk\temp\test\test\test.cpp(54) : error C2065: 'argv' : undeclared identifier 1>c:\junk\temp\test\test\test.cpp(54) : error C2059: syntax error : ']' 1>c:\junk\temp\test\test\test.cpp(55) : error C2143: syntax error : missing ';' before '{' 1>c:\junk\temp\test\test\test.cpp(58) : error C2143: syntax error : missing ';' before '}' 1>c:\junk\temp\test\test\test.cpp(60) : error C2143: syntax error : missing ';' before '}' 1>c:\junk\temp\test\test\test.cpp(60) : fatal error C1004: unexpected end-of-file found 1>Build log was saved at "file://c:\junk\temp\test\test\Debug\BuildLog.htm" 1>test - 12 error(s), 1 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== Any ideas? Thanks!

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• PHP Form - Empty input enter this text - Validation

  - by James Skelton

  No doubt very simple question for someone with php knowledge. I have a form with a datepicker, all is fine when a user has selected a date the email is send with: Date: 2012 04 10 But i would like if the user has skipped this and left blank (as i have not made this required) to send as: Date: Not Entered (<-- Or something) Instead at the minute of course it reads: Date: Form input <input type="text" class="form-control" id="datepicker" name="datepicker" size="50" value="Date Of Wedding" /> This is the validator $(document).ready(function(){ //validation contact form $('#submit').click(function(event){ event.preventDefault(); var fname = $('#name').val(); var validInput = new RegExp(/^[a-zA-Z0-9\s]+$/); var email = $('#email').val(); var validEmail = new RegExp(/^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/); var message = $('#message').val(); if(fname==''){ showError('<div class="alert alert-danger">Please enter your name.</div>', $('#name')); $('#name').addClass('required'); return;} if(!validInput.test(fname)){ showError('<div class="alert alert-danger">Please enter a valid name.</div>', $('#name')); $('#name').addClass('required'); return;} if(email==''){ showError('<div class="alert alert-danger">Please enter an email address.</div>', $('#email')); $('#email').addClass('required'); return;} if(!validEmail.test(email)){ showError('<div class="alert alert-danger">Please enter a valid email.</div>', $('#email')); $('#email').addClass('required'); return;} if(message==''){ showError('<div class="alert alert-danger">Please enter a message.</div>', $('#message')); $('#message').addClass('required'); return;} // setup some local variables var request; var form = $(this).closest('form'); // serialize the data in the form var serializedData = form.serialize(); // fire off the request to /contact.php request = $.ajax({ url: "contact.php", type: "post", data: serializedData }); // callback handler that will be called on success request.done(function (response, textStatus, jqXHR){ $('.contactWrap').show( 'slow' ).fadeIn("slow").html(' <div class="alert alert-success centered"><h3>Thank you! Your message has been sent.</h3></div> '); }); // callback handler that will be called on failure request.fail(function (jqXHR, textStatus, errorThrown){ // log the error to the console console.error( "The following error occured: "+ textStatus, errorThrown ); }); }); //remove 'required' class and hide error $('input, textarea').keyup( function(event){ if($(this).hasClass('required')){ $(this).removeClass('required'); $('.error').hide("slow").fadeOut("slow"); } }); // show error showError = function (error, target){ $('.error').removeClass('hidden').show("slow").fadeIn("slow").html(error); $('.error').data('target', target); $(target).focus(); console.log(target); console.log(error); return; } });

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• Getting up to speed on modern architecture

  - by Matt Thrower

  Hi, I don't have any formal qualifications in computer science, rather I taught myself classic ASP back in the days of the dotcom boom and managed to get myself a job and my career developed from there. I was a confident and, I think, pretty good programmer in ASP 3 but as others have observed one of the problems with classic ASP was that it did a very good job of hiding the nitty-gritty of http so you could become quite competent as a programmer on the basis of relatively poor understanding of the technology you were working with. When I changed on to .NET at first I treated it like classic ASP, developing stand-alone applications as individual websites simply because I didn't know any better at the time. I moved jobs at this point and spent the next several years working on a single site whose architecture relied heavily on custom objects: in other words I gained a lot of experience working with .NET as a middle-tier development tool using a quite old-fashioned approach to OO design along the lines of the classic "car" class example that's so often used to teach OO. Breaking down programs into blocks of functionality and basing your classes and methods around that. Although we worked under an Agile approach to manage the work the whole setup was classic client/server stuff. That suited me and I gradually got to grips with .NET and started using it far more in the manner that it should be, and I began to see the power inherent in the technology and precisely why it was so much better than good old ASP 3. In my latest job I have found myself suddenly dropped in at the deep end with two quite young, skilled and very cutting-edge programmers. They've built a site architecture which is modelling along a lot of stuff which is new to me and which, in truth I'm having a lot of trouble understanding. The application is built on a cloud computing model with multi-tenancy and the architecture is all loosely coupled using a lot of interfaces, factories and the like. They use nHibernate a lot too. Shortly after I joined, both these guys left and I'm now supposedly the senior developer on a system whose technology and architecture I don't really understand and I have no-one to ask questions of. Except you, the internet. Frankly I feel like I've been pitched in at the deep end and I'm sinking. I'm not sure if this is because I lack the educational background to understand this stuff, if I'm simply not mathematically minded enough for modern computing (my maths was never great - my approach to design is often to simply debug until it works, then refactor until it looks neat), or whether I've simply been presented with too much of too radical a nature at once. But the only way to find out which it is is to try and learn it. So can anyone suggest some good places to start? Good books, tutorials or blogs? I've found a lot of internet material simply presupposes a level of understanding that I just don't have. Your advice is much appreciated. Help a middle-aged, stuck in the mud developer get enthusastic again! Please!

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• How can i clear a SQLite database each time i start my app

  - by AndroidUser99

  Hi, i want that each time i start my app my SQLite database get's cleaned for this, i need to make a method on my class MyDBAdapter.java code examples are welcome, i have no idea how to do it this is the dbadapter/helper i'm using: public class MyDbAdapter { private static final String TAG = "NotesDbAdapter"; private DatabaseHelper mDbHelper; private SQLiteDatabase mDb; private static final String DATABASE_NAME = "gpslocdb"; private static final String PERMISSION_TABLE_CREATE = "CREATE TABLE permission ( fk_email1 varchar, fk_email2 varchar, validated tinyint, hour1 time default '08:00:00', hour2 time default '20:00:00', date1 date, date2 date, weekend tinyint default '0', fk_type varchar, PRIMARY KEY (fk_email1,fk_email2))"; private static final String USER_TABLE_CREATE = "CREATE TABLE user ( email varchar, password varchar, fullName varchar, mobilePhone varchar, mobileOperatingSystem varchar, PRIMARY KEY (email))"; private static final int DATABASE_VERSION = 2; private final Context mCtx; private static class DatabaseHelper extends SQLiteOpenHelper { DatabaseHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(PERMISSION_TABLE_CREATE); db.execSQL(USER_TABLE_CREATE); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { db.execSQL("DROP TABLE IF EXISTS user"); db.execSQL("DROP TABLE IF EXISTS permission"); onCreate(db); } } /** * Constructor - takes the context to allow the database to be * opened/created * * @param ctx the Context within which to work */ public MyDbAdapter(Context ctx) { this.mCtx = ctx; } /** * Open the database. If it cannot be opened, try to create a new * instance of the database. If it cannot be created, throw an exception to * signal the failure * * @return this (self reference, allowing this to be chained in an * initialization call) * @throws SQLException if the database could be neither opened or created */ public MyDbAdapter open() throws SQLException { mDbHelper = new DatabaseHelper(mCtx); mDb = mDbHelper.getWritableDatabase(); return this; } public void close() { mDbHelper.close(); } public long createUser(String email, String password, String fullName, String mobilePhone, String mobileOperatingSystem) { ContentValues initialValues = new ContentValues(); initialValues.put("email",email); initialValues.put("password",password); initialValues.put("fullName",fullName); initialValues.put("mobilePhone",mobilePhone); initialValues.put("mobileOperatingSystem",mobileOperatingSystem); return mDb.insert("user", null, initialValues); } public Cursor fetchAllUsers() { return mDb.query("user", new String[] {"email", "password", "fullName", "mobilePhone", "mobileOperatingSystem"}, null, null, null, null, null); } public Cursor fetchUser(String email) throws SQLException { Cursor mCursor = mDb.query(true, "user", new String[] {"email", "password", "fullName", "mobilePhone", "mobileOperatingSystem"} , "email" + "=" + email, null, null, null, null, null); if (mCursor != null) { mCursor.moveToFirst(); } return mCursor; } public List<Friend> retrieveAllUsers() { List <Friend> friends=new ArrayList<Friend>(); Cursor result=fetchAllUsers(); if( result.moveToFirst() ){ do{ //note.getString(note.getColumnIndexOrThrow(NotesDbAdapter.KEY_TITLE))); friends.add(new Friend(result.getString(result.getColumnIndexOrThrow("email")), "","","","")); }while( result.moveToNext() ); } return friends; } }

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• Can't save my picture

  - by mamii

  I want to save the image that I draw, but I always failure is reported. I have tested and tried but I can correct any errors. Therefore, I appeal to you. This store is for me as a "cancer sore". And what is the drawing application without the possibility shranjevnja? sucks: D Question: What is wrong with my code for storage? or anything else? Posts: 09-12 07:30:34.346: E / Panel (8003): IOEception 09-12 07:30:34.346: E / Panel (8003): java.io.IOException: Parent directory of file does not exist: / sdcard/anppp/2012Sep1273034.png 09-12 07:30:34.346: E / Panel (8003): at java.io.File.createNewFile (File.java: 1263) 09-12 07:30:34.346: E / Panel (8003): at aa.bb.cc.Panel.saveapp (Panel.java: 67) 09-12 07:30:34.346: E / Panel (8003): at aa.bb.cc.AndroidPaint.onOptionsItemSelected (AndroidPaint.java: 94) 09-12 07:30:34.346: E / Panel (8003): at android.app.Activity.onMenuItemSelected (Activity.java: 2170) 09-12 07:30:34.346: E / Panel (8003): at com.android.internal.policy.impl.PhoneWindow.onMenuItemSelected (PhoneWindow.java: 730) 09-12 07:30:34.346: E / Panel (8003): at com.android.internal.view.menu.MenuItemImpl.invoke (MenuItemImpl.java: 139) 09-12 07:30:34.346: E / Panel (8003): at com.android.internal.view.menu.MenuBuilder.performItemAction (MenuBuilder.java: 855) 09-12 07:30:34.346: E / Panel (8003): at com.android.internal.view.menu.ExpandedMenuView.invokeItem (ExpandedMenuView.java: 89) 09-12 07:30:34.346: E / Panel (8003): at com.android.internal.view.menu.ExpandedMenuView.onItemClick (ExpandedMenuView.java: 93) 09-12 07:30:34.346: E / Panel (8003): at android.widget.AdapterView.performItemClick (AdapterView.java: 284) 09-12 07:30:34.346: E / Panel (8003): at android.widget.ListView.performItemClick (ListView.java: 3285) 09-12 07:30:34.346: E / Panel (8003): at android.widget.AbsListView $ PerformClick.run (AbsListView.java: 1640) 09-12 07:30:34.346: E / Panel (8003): at android.os.Handler.handleCallback (Handler.java: 587) 09-12 07:30:34.346: E / Panel (8003): at android.os.Handler.dispatchMessage (Handler.java: 92) 09-12 07:30:34.346: E / Panel (8003): at android.os.Looper.loop (Looper.java: 123) 09-12 07:30:34.346: E / Panel (8003): at android.app.ActivityThread.main (ActivityThread.java: 4363) 09-12 07:30:34.346: E / Panel (8003): at java.lang.reflect.Method.invokeNative (Native Method) 09-12 07:30:34.346: E / Panel (8003): at java.lang.reflect.Method.invoke (Method.java: 521) 09-12 07:30:34.346: E / Panel (8003): at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run (ZygoteInit.java: 860) 09-12 07:30:34.346: E / Panel (8003): at com.android.internal.os.ZygoteInit.main (ZygoteInit.java: 618) 09-12 07:30:34.346: E / Panel (8003): at dalvik.system.NativeStart.main (Native Method) There is code: private Bitmap mBitmap; private Canvas mCanvas; private Bitmap tmpBitmap; private Canvas tmpCanvas; private DrawHandler mDrawHandler; private Canvas tCanvas; private String mImagePath = Environment.getExternalStorageDirectory() + "/anppp"; private File file; public void saveapp() { Calendar currentDate = Calendar.getInstance(); SimpleDateFormat formatter= new SimpleDateFormat("yyyyMMMddHmmss"); String dateNow = formatter.format(currentDate.getTime()); file = new File(mImagePath + "/" + dateNow +".png"); FileOutputStream fos; try { file.createNewFile(); fos = new FileOutputStream(file); tmpBitmap.compress(Bitmap.CompressFormat.PNG, 100, fos); fos.close(); } catch (FileNotFoundException e) { Log.e("Panel", "FileNotFoundException", e); } catch (IOException e) { Log.e("Panel", "IOEception", e); } } That's it .. I do not know what could be wrong ;(

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• VB.Net 2008 IDE hanging - MSVB7.dll eating 100% CPU when editing code

  - by Andrew Backer

  I am having a problem with msvb7.dll eating 50%+ cpu on my dual core system. This usually lasts 10-30 seconds or so, during which time the IDE is non-responsive. This occurs when I do pretty much anything in the text editor, and can be replicated by simply adding blank lines to a function, and then deleting them. Or pasting some code. Or... lotsa stuff. SP1 installed I had DevExpress' refactor/coderush, components, and codeit.right installed, but have removed all 3 of them. (I had installed the latest version of Refactor Pro! (9.3.4), perhaps the day before) I have tried a VS.NET Repair. There is a kb that referenced some cpu destroying with vb, but it was included in SP1 Also: The solution consists of ~30 VB projects and 2 C# projects 8 other developers aren't having any issues with this (or at least not the SAME issues, we all have em) Clean get from TFS was done Project builds properly, can can even debug. This doesn't seem to happen on really small solutions, but perhaps it does and it just goes away super quick. Any clues at all as to what might be causing this, or how to fix it? I REALLY don't want to lose another day uninstalling and reinstalling and patching and so on =) If that even fixes it. Here is the stack trace (process explorer) that I get from the threads window when the msvb7.dll is churning. --- title in process explorer [threads] tab for process -------- cpu:49.28% cswitch delta: 300 to 3500 startaddress: [msvb7.dll+0x4218c] msvb7.dll version: 9.0.30729.1 --- actual stack trace ------- ntkrnlpa.exe!KiUnexpectedInterrupt+0x121 ntkrnlpa.exe!ZwYieldExecution+0x1c56 ntkrnlpa.exe!KiDispatchInterrupt+0x72e NDIS.sys!NdisFreeToBlockPool+0x15e1 // shortened stack trace. all of these are from msvb7, msvb7.dll+0x46ce7 <- 0x2676a <- 0x2698e <- 0x38031 <- 0x2659f <- 0x26644 msvb7.dll+0x25f29 <- 0x2ac7a <- 0x27522 <- 0x274a0 <- 0x2b5ce <- 0x2b6e4 msvb7.dll+0x67d0a <- 0x68551 <- 0x6817b <- 0x681f0 <- 0x67c38 <- 0x65fa8 msvb7.dll+0x666c6 <- 0x6672c <- 0x6673d <- 0x6677c <- 0x667b4 <- 0x63c77 msvb7.dll+0x63e97 <- 0x42c3a <- 0x42bc1 <- 0x41bd7 kernel32.dll!GetModuleFileNameA+0x1b4 This is the list of stuff from "copy info" in help-about, shortened to a resonable length. Microsoft Visual Studio 2008 | Version 9.0.30729.1 SP Microsoft Visual Studio 2008 Professional Edition - ENU Service Pack 1 (KB945140) KB945140 Microsoft .NET Framework | Version 3.5 SP1 Microsoft Visual Basic 2008 Microsoft Visual C# 2008 Microsoft Visual F# for Visual Studio 2008 Microsoft Visual Studio 2008 Team Explorer | Version 9.0.30729.1 Microsoft Visual Studio 2008 Tools for Office Microsoft Visual Web Developer 2008 Hotfix for Microsoft Visual Studio 2008 Professional Edition - ENU KB944899, KB945282, KB946040, KB946308, KB946344, KB946581, KB947171 KB947173, KB947180, KB947540, KB947789, KB948127, KB946260, KB946458, KB948816 Microsoft Recipe Framework Package 8.0 Process Editor WIT Designer 1.4.0.0 Process Editor for Microsoft Visual Studio Team Foundation Server, Version 1.4.0.0 tangible T4 Editor 9.0 tangible T4 Text Template Editor - T4 Editor tangibleprojectsystem 1.0 Team Foundation Server Power Tools October 2008 SQL Prompt 4.0 (disabled)

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• unmet dependencies in Ubuntu 12.04

  - by lee.O

  I tried today to install a dvb-card on my Ubuntu 12.04 (Linux blauhai-linux 3.2.0-25-generic #40-Ubuntu SMP Wed May 23 20:30:51 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux ). The installation failed with an error. After that, i tried to install python (it was already installed but i got this error): linux:~$ sudo apt-get install git Reading package lists... Done Building dependency tree Reading state information... Done git is already the newest version. You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies: python-glade2:i386 : Depends: python:i386 (< 2.5) but it is not going to be installed Depends: python-support:i386 (= 0.3.4) but it is not installable Depends: python:i386 (= 2.4) but it is not going to be installed Depends: libglade2-0:i386 (= 1:2.5.1) but it is not going to be installed Depends: python-gtk2:i386 (= 2.8.6-8) but it is not going to be installed python-numeric:i386 : Depends: python:i386 (< 2.5) but it is not going to be installed Depends: python:i386 (= 2.3) but it is not going to be installed Depends: python-central:i386 (= 0.5.7) but it is not installable E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution). well, i can read and tried the proposed command, but then i get this: linux:~$ sudo apt-get -f install Reading package lists... Done Building dependency tree Reading state information... Done Correcting dependencies... Done The following packages were automatically installed and are no longer required: libopenal1:i386 libsdl-ttf2.0-0:i386 libkrb5-3:i386 libgconf-2-4:i386 libsm-dev libatk1.0-0:i386 libk5crypto3:i386 libstdc++5:i386 libqt4-declarative:i386 libxcomposite1:i386 libice-dev libgail18:i386 libldap-2.4-2:i386 libao-common libv4l-0:i386 liblcms1:i386 libqt4-qt3support:i386 libroken18-heimdal:i386 libunistring0:i386 libcupsimage2:i386 libgphoto2-port0:i386 libidn11:i386 libnss3:i386 libcaca0:i386 gtk2-engines:i386 libgudev-1.0-0:i386 libjpeg-turbo8:i386 libpthread-stubs0 libcairo-gobject2:i386 libavc1394-0:i386 libjpeg8:i386 libotr2 libaio1:i386 libsane:i386 odbcinst1debian2 odbcinst1debian2:i386 libqt4-test:i386 libqt4-script:i386 libqt4-designer:i386 libsdl-mixer1.2:i386 libqt4-network:i386 libqt4-dbus:i386 libcap2:i386 libproxy1:i386 ibus-gtk:i386 libdbus-glib-1-2:i386 libtdb1:i386 libasn1-8-heimdal:i386 libspeex1:i386 libxslt1.1:i386 libgomp1:i386 libcapi20-3:i386 libibus-1.0-0:i386 libcairo2:i386 libgnutls26:i386 libopenal-data odbcinst libgssapi3-heimdal:i386 libcanberra0:i386 libtasn1-3:i386 libfreetype6:i386 x11proto-kb-dev gtk2-engines-murrine:i386 libwavpack1:i386 libqt4-opengl:i386 libsoup-gnome2.4-1:i386 libv4lconvert0:i386 gstreamer0.10-plugins-good:i386 libc6-i386 lib32gcc1 libqt4-xmlpatterns:i386 librsvg2-common:i386 libdatrie1:i386 xtrans-dev libavahi-common-data:i386 libiec61883-0:i386 lib32asound2 libgdk-pixbuf2.0-0:i386 libsdl-image1.2:i386 libp11-kit0:i386 x11proto-input-dev libwind0-heimdal:i386 libpixman-1-0:i386 libsdl1.2debian:i386 libxaw7:i386 libgdbm3:i386 libcups2:i386 libcurl3:i386 libqtcore4:i386 libxinerama1:i386 libesd0:i386 libmikmod2:i386 libkrb5support0:i386 libxft2:i386 libxt-dev libcroco3:i386 libpulse-mainloop-glib0:i386 libice6:i386 libaa1:i386 libieee1284-3:i386 libgcrypt11:i386 libthai0:i386 libao4:i386 libkeyutils1:i386 libxmu6:i386 libcanberra-gtk0:i386 libvorbisfile3:i386 libqt4-sql:i386 esound-common libxpm4:i386 libqt4-svg:i386 libusb-0.1-4:i386 libgail-common:i386 libxrender1:i386 libhcrypto4-heimdal:i386 libraw1394-11:i386 libnspr4:i386 libshout3:i386 libdv4:i386 libhx509-5-heimdal:i386 libxau-dev libqt4-xml:i386 gstreamer0.10-x:i386 libgettextpo0:i386 libxss1:i386 libgd2-xpm:i386 libheimbase1-heimdal:i386 libtiff4:i386 libsdl-net1.2:i386 libjasper1:i386 libgnome-keyring0:i386 libxtst6:i386 gtk2-engines-pixbuf:i386 libqtgui4:i386 libtag1c2a:i386 librsvg2-2:i386 libavahi-client3:i386 libssl0.9.8:i386 libmpg123-0:i386 libmad0:i386 libsasl2-2:i386 xorg-sgml-doctools libgsoap1 gtk2-engines-oxygen:i386 libfontconfig1:i386 xaw3dg:i386 libpango1.0-0:i386 libsm6:i386 libx11-dev libheimntlm0-heimdal:i386 libpulsedsp:i386 lib32stdc++6 libx11-doc libqt4-sql-mysql:i386 libxcb-render0:i386 libodbc1:i386 libexif12:i386 libqt4-scripttools:i386 librtmp0:i386 libgssapi-krb5-2:i386 libxi6:i386 libqtwebkit4:i386 libxcb1-dev libxp6:i386 libaudio2:i386 libxcursor1:i386 libxcb-shm0:i386 libxt6:i386 libxv1:i386 libsasl2-modules:i386 libavahi-common3:i386 libxrandr2:i386 x11proto-core-dev libsqlite3-0:i386 libmng1:i386 libgtk2.0-0:i386 libxdmcp-dev libpthread-stubs0-dev libltdl7:i386 libkrb5-26-heimdal:i386 libssl1.0.0:i386 glib-networking:i386 libgpg-error0:i386 libsoup2.4-1:i386 libgphoto2-2:i386 libtag1-vanilla:i386 libaudiofile1:i386 libglade2-0:i386 Use 'apt-get autoremove' to remove them. The following extra packages will be installed: default-jre default-jre-headless icedtea-6-jre-cacao icedtea-6-jre-jamvm icedtea-netx icedtea-netx-common libglade2-0:i386 libpython3.2 openjdk-6-jre openjdk-6-jre-headless openjdk-6-jre-lib python3 python3-minimal python3-uno python3.2 python3.2-minimal Suggested packages: icedtea-plugin sun-java6-fonts fonts-ipafont-gothic fonts-ipafont-mincho ttf-telugu-fonts ttf-oriya-fonts ttf-kannada-fonts ttf-bengali-fonts python3-doc python3-tk python3.2-doc binfmt-support The following packages will be REMOVED: activity-log-manager-control-center aisleriot alacarte apparmor apport apport-gtk apt-xapian-index aptdaemon apturl apturl-common bluez bluez-alsa bluez-alsa:i386 bluez-gstreamer checkbox checkbox-qt command-not-found compiz compiz-gnome compiz-plugins-main-default compizconfig-backend-gconf deja-dup duplicity eog evolution-data-server firefox firefox-globalmenu firefox-gnome-support foomatic-db-compressed-ppds gconf-editor gconf2 gdb gedit gir1.2-mutter-3.0 gir1.2-peas-1.0 gir1.2-rb-3.0 gir1.2-totem-1.0 gir1.2-ubuntuoneui-3.0 gksu gnome-applets gnome-applets-data gnome-bluetooth gnome-contacts gnome-control-center gnome-media gnome-menus gnome-orca gnome-panel gnome-panel-data gnome-session-fallback gnome-shell gnome-sudoku gnome-terminal gnome-terminal-data gnome-themes-standard gnome-tweak-tool gnome-user-share gstreamer0.10-gconf gwibber gwibber-service gwibber-service-facebook gwibber-service-identica gwibber-service-twitter hplip hplip-data ia32-libs ia32-libs-multiarch:i386 ibus ibus-pinyin ibus-table indicator-datetime indicator-power jockey-common jockey-gtk landscape-client-ui-install language-selector-common language-selector-gnome launchpad-integration libcanberra-gtk-module libcanberra-gtk-module:i386 libcanberra-gtk3-module libcompizconfig0 libfolks-eds25 libgksu2-0 libgnome-media-profiles-3.0-0 libgnome2-0 libgnome2-common libgnomevfs2-0 libgnomevfs2-common libgweather-3-0 libgweather-common libgwibber-gtk2 libgwibber2 libmetacity-private0 libmutter0 libpeas-1.0-0 libpurple-bin libpython2.7 libreoffice-gnome librhythmbox-core5 libsyncdaemon-1.0-1 libtotem0 libubuntuoneui-3.0-1 light-themes lsb-release metacity metacity-common mutter-common nautilus-dropbox nautilus-share network-manager-gnome nvidia-common nvidia-settings nvidia-settings-updates onboard oneconf openjdk-7-jdk openjdk-7-jre openprinting-ppds pidgin pidgin-libnotify pidgin-otr printer-driver-foo2zjs printer-driver-ptouch printer-driver-pxljr printer-driver-sag-gdi printer-driver-splix python python-appindicator python-apport python-apt python-apt-common python-aptdaemon python-aptdaemon.gtk3widgets python-aptdaemon.pkcompat python-brlapi python-cairo python-central python-chardet python-configglue python-crypto python-cups python-cupshelpers python-dateutil python-dbus python-debian python-debtagshw python-defer python-dirspec python-egenix-mxdatetime python-egenix-mxtools python-gconf python-gdbm python-gi python-gi-cairo python-glade2:i386 python-gmenu python-gnomekeyring python-gnupginterface python-gobject python-gobject-2 python-gpgme python-gst0.10 python-gtk2 python-httplib2 python-ibus python-imaging python-keyring python-launchpadlib python-lazr.restfulclient python-lazr.uri python-libproxy python-libxml2 python-louis python-mako python-markupsafe python-minimal python-notify python-numeric:i386 python-oauth python-openssl python-packagekit python-pam python-pexpect python-piston-mini-client python-pkg-resources python-problem-report python-protobuf python-pyatspi2 python-pycurl python-pyinotify python-renderpm python-reportlab python-reportlab-accel python-serial python-simplejson python-smbc python-software-properties python-speechd python-twisted-bin python-twisted-core python-twisted-names python-twisted-web python-ubuntu-sso-client python-ubuntuone-client python-ubuntuone-control-panel python-ubuntuone-storageprotocol python-uno python-virtkey python-wadllib python-xapian python-xdg python-xkit python-zeitgeist python-zope.interface python2.7 python2.7-minimal rhythmbox rhythmbox-mozilla rhythmbox-plugin-cdrecorder rhythmbox-plugin-magnatune rhythmbox-plugin-zeitgeist rhythmbox-plugins rhythmbox-ubuntuone screen-resolution-extra sessioninstaller skype software-center software-center-aptdaemon-plugins software-properties-common software-properties-gtk system-config-printer-common system-config-printer-gnome system-config-printer-udev texlive-extra-utils totem totem-mozilla totem-plugins ubuntu-artwork ubuntu-desktop ubuntu-minimal ubuntu-sso-client ubuntu-sso-client-gtk ubuntu-standard ubuntu-system-service ubuntuone-client ubuntuone-client-gnome ubuntuone-control-panel ubuntuone-couch ubuntuone-installer ufw unattended-upgrades unity unity-2d unity-common unity-lens-applications unity-lens-video unity-scope-musicstores unity-scope-video-remote update-manager update-manager-core update-notifier update-notifier-common usb-creator-common usb-creator-gtk virtualbox virtualbox-dkms virtualbox-qt xdiagnose xul-ext-ubufox zeitgeist zeitgeist-core zeitgeist-datahub The following NEW packages will be installed: default-jre default-jre-headless icedtea-6-jre-cacao icedtea-6-jre-jamvm icedtea-netx icedtea-netx-common libglade2-0:i386 libpython3.2 openjdk-6-jre openjdk-6-jre-headless openjdk-6-jre-lib python3 python3-minimal python3-uno python3.2 python3.2-minimal WARNING: The following essential packages will be removed. This should NOT be done unless you know exactly what you are doing! python-minimal python2.7-minimal (due to python-minimal) 0 upgraded, 16 newly installed, 273 to remove and 0 not upgraded. 2 not fully installed or removed. Need to get 39.1 MB of archives. After this operation, 324 MB disk space will be freed. You are about to do something potentially harmful. To continue type in the phrase 'Yes, do as I say!' ?] Thats not good, is it?! Should i run this command or should i run another command to fix this problem? Would be great if somebody can help me. :) Thanks in advance. best regards

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• Silverlight 4 Tools for VS 2010 and WCF RIA Services Released

  - by ScottGu

  The final release of the Silverlight 4 Tools for Visual Studio 2010 and WCF RIA Services is now available for download.  Download and Install If you already have Visual Studio 2010 installed (or the free Visual Web Developer 2010 Express), then you can install both the Silverlight 4 Tooling Support as well as WCF RIA Services support by downloading and running this setup package (note: please make sure to uninstall the preview release of the Silverlight 4 Tools for VS 2010 if you have previously installed that).  The Silverlight 4 Tools for VS 2010 package extends the Silverlight support built into Visual Studio 2010 and enables support for Silverlight 4 applications as well.  It also installs WCF RIA Services application templates and libraries: Today’s release includes the English edition of the Silverlight 4 Tooling – localized versions will be available next month for other Visual Studio languages as well. Silverlight Tooling Support Visual Studio 2010 includes rich tooling support for building Silverlight and WPF applications. It includes a WYSIWYG designer surface that enables you to easily use controls to construct UI – including the ability to take advantage of layout containers, and apply styles and resources: The VS 2010 designer enables you to leverage the rich data binding support within Silverlight and WPF, and easily wire-up bindings on controls.  The Data Sources window within Silverlight projects can be used to reference POCO objects (plain old CLR objects), WCF Services, WCF RIA Services client proxies or SharePoint Lists.  For example, let’s assume we add a “Person” class like below to our project: We could then add it to the Data Source window which will cause it to show up like below in the IDE: We can optionally customize the default UI control types that are associated for each property on the object.  For example, below we’ll default the BirthDate property to be represented by a “DatePicker” control: And then when we drag/drop the Person type from the Data Sources onto the design-surface it will automatically create UI controls that are bound to the properties of our Person class: VS 2010 allows you to optionally customize each UI binding further by selecting a control, and then right-click on any of its properties within the property-grid and pull up the “Apply Bindings” dialog: This will bring up a floating data-binding dialog that enables you to easily configure things like the binding path on the data source object, specify a format convertor, specify string-format settings, specify how validation errors should be handled, etc: In addition to providing WYSIWYG designer support for WPF and Silverlight applications, VS 2010 also provides rich XAML intellisense and code editing support – enabling a rich source editing environment. Silverlight 4 Tool Enhancements Today’s Silverlight 4 Tooling Release for VS 2010 includes a bunch of nice new features.  These include: Support for Silverlight Out of Browser Applications and Elevated Trust Applications You can open up a Silverlight application’s project properties window and click the “Enable Running Application Out of Browser” checkbox to enable you to install an offline, out of browser, version of your Silverlight 4 application.  You can then customize a number of “out of browser” settings of your application within Visual Studio: Notice above how you can now indicate that you want to run with elevated trust, with hardware graphics acceleration, as well as customize things like the Window style of the application (allowing you to build a nice polished window style for consumer applications). Support for Implicit Styles and “Go to Value Definition” Support: Silverlight 4 now allows you to define “implicit styles” for your applications.  This allows you to style controls by type (for example: have a default look for all buttons) and avoid you having to explicitly reference styles from each control.  In addition to honoring implicit styles on the designer-surface, VS 2010 also now allows you to right click on any control (or on one of it properties) and choose the “Go to Value Definition…” context menu to jump to the XAML where the style is defined, and from there you can easily navigate onward to any referenced resources.  This makes it much easier to figure out questions like “why is my button red?”: Style Intellisense VS 2010 enables you to easily modify styles you already have in XAML, and now you get intellisense for properties and their values within a style based on the TargetType of the specified control.  For example, below we have a style being set for controls of type “Button” (this is indicated by the “TargetType” property).  Notice how intellisense now automatically shows us properties for the Button control (even within the <Setter> element): Great Video - Watch the Silverlight Designer Features in Action You can see all of the above Silverlight 4 Tools for Visual Studio 2010 features (and some more cool ones I haven’t mentioned) demonstrated in action within this 20 minute Silverlight.TV video on Channel 9: WCF RIA Services Today we also shipped the V1 release of WCF RIA Services.  It is included and automatically installed as part of the Silverlight 4 Tools for Visual Studio 2010 setup. WCF RIA Services makes it much easier to build business applications with Silverlight.  It simplifies the traditional n-tier application pattern by bringing together the ASP.NET and Silverlight platforms using the power of WCF for communication.  WCF RIA Services provides a pattern to write application logic that runs on the mid-tier and controls access to data for queries, changes and custom operations. It also provides end-to-end support for common tasks such as data validation, authentication and authorization based on roles by integrating with Silverlight components on the client and ASP.NET on the mid-tier. Put simply – it makes it much easier to query data stored on a server from a client machine, optionally manipulate/modify the data on the client, and then save it back to the server.  It supports a validation architecture that helps ensure that your data is kept secure and business rules are applied consistently on both the client and middle-tiers. WCF RIA Services uses WCF for communication between the client and the server  It supports both an optimized .NET to .NET binary serialization format, as well as a set of open extensions to the ATOM format known as ODATA and an optional JavaScript Object Notation (JSON) format that can be used by any client. You can hear Nikhil and Dinesh talk a little about WCF RIA Services in this 13 minutes Channel 9 video. Putting it all Together – the Silverlight 4 Training Kit Check out the Silverlight 4 Training Kit to learn more about how to build business applications with Silverlight 4, Visual Studio 2010 and WCF RIA Services. The training kit includes 8 modules, 25 videos, and several hands-on labs that explain Silverlight 4 and WCF RIA Services concepts and walks you through building an end-to-end application with them.    The training kit is available for free and is a great way to get started. Summary I’m really excited about today’s release – as they really complete the Silverlight development story and deliver a great end to end runtime + tooling story for building applications.  All of the above features are available for use both in VS 2010 as well as the free Visual Web Developer 2010 Express Edition – making it really easy to get started building great solutions. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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