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• beginner's question about CSS

  - by Nitesh Panchal

  Hello, I am creating a website and i want to allow personalization to individual users upto some extent like changing font family, background color etc. The problem with this is that, my default css file that i load has already default classes for everything. Now when i fetch the background color from my database, then if there is null value for background color then default css class of mystylesheet.css should be loaded and if the value is not null, then i want to override this with my default css. How is it possible? Thanks in advance :)

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• How can I filter out the "My Computer"-option in a SWT DirectoryDialog?

  - by Superfisi

  Hello *, in our Eclipse RCP application running on Windows XP we use a DirectoryDialog, in which the user should... ahmm... choose a directory! :D The problem is: If the user selects the "My Computer"-option (in German Windows "Arbeitsplatz") the Dialog returns null. The DirectoryDialog provides a method setFilterPath(String path) in which I put the File.pathSeparatorChar (to remain OS-independant). My suggestion was that if there has to be a file separator in the directory the "My Computer"-option would be ignored cause it is null - for example the "OK"-button would be greyed out or sth. like that... but it is also valid to klick "OK". Any suggestions from your side? :D Thanks in advance! Alex

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• Why did this code still work?

  - by bstullkid

  Some old code that I just came across: MLIST * new_mlist_link() { MLIST *new_link = (MLIST * ) malloc(sizeof(MLIST)); new_link->next = NULL; new_link->mapi = NULL; new_link->result = 0; } This was being called to build a linked list, however I noticed there is no statement: return new_link; Even without the return statement there, the list still got built properly. Why did this happen? EDT: Platform: Mandriva 2009 64bit Linux 2.6.24.7-server GCC 4.2.3-6mnb1

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• Positioning child panels using FlowLayout

  - by extro

  I have two panels: main_panel child_panel The main_panel layout is set using: main_panel.setLayout(flowlayout) I then added child_panel to main_panel: main_panel.add(child_panel) The child_panel gets added to main_panel but its position is at the cross-section of horizontal midpoint and top vertical section of screen. I want child_panel to be at the top left corner, something I could have done by using child_panel.setlocation(a,b) method, if I have set the layout of main_panel as null. I have used FlowLayout here because I want components in the JPanel to keep adjusting with the size of JFrame. So can I add child_panel to main_panel at the exact location I want, even if I set the Layout of main_panel as not null?

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• assignment from incompatible pointer type

  - by Hristo

  I have set up the following struct: typedef struct _thread_node_t { pthread_t thread; struct thread_node_t *next; } thread_node_t; ... and then I have defined: // create thread to for incoming connection thread_node_t *thread_node = (thread_node_t*) malloc(sizeof(thread_node_t)); pthread_create(&(thread_node->thread), NULL, client_thread, &csFD); thread_node->next = thread_arr; // assignment from incompatible pointer type thread_arr = thread_node; where thread_arr is thread_node_t *thread_arr = NULL; I don't understand why the compiler is complaining. Maybe I'm misunderstanding something.

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• MySQL pivot tables - covert rows to columns

  - by user2723490

  This is the structure of my table: Then I run a query SELECT `date`,`index_name`,`results` FROM `mst_ind` WHERE `index_name` IN ('MSCI EAFE Mid NR USD', 'Alerian MLP PR USD') AND `time_period`='M1' and get a table like How can I convert "index_name" rows to columns like: date | MSCI EAFE Mid NR USD | Alerian MLP PR USD etc In other words I need each column to represent an index and rows to represent date-result. I understand that MySQL doesn't have pivot table functions. What is the easiest way of doing this? I've tried this code, but it generates an error: SELECT `date`, MAX(IF(index_name = 'Alerian MLP PR USD' AND `time_period`='M1', results, NULL)) AS res1, MAX(IF(index_name = 'MSCI EAFE Mid NR USD' AND `time_period`='M1', results, NULL)) AS res2 FROM `mst_ind` GROUP BY `date I need to make the conversion on the query level - not PHP. Please suggest a nice and elegant solution. Thanks!

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• Showing an image after laoding it from sql database

  - by user330075

  I have a problem showing the image form database in a view Details and a ImageController. Inside the view i have: img src=Url.Action("GetFile","Image", new {id= Model.id}) and in controller: public FileContentResult GetFile(int idl) { //int idl = 32; SqlDataReader rdr; byte[] fileContent = null; ........... return File(,,); } When the view is called, function GetFile it just wont work,but if i cut out the parameter int id1 and i instantiate it as a variable it'l work. public FileContentResult GetFile() { int idl = 32; SqlDataReader rdr; byte[] fileContent = null; ........... return File(,,); } Why?

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• XMLHttpRequest.status always returning 0

  - by Michael

  html <a href="#" onclick="MyObj.startup()">click me</a> js code var MyObj = { startup : function() { var ajax = null; ajax = new XMLHttpRequest(); ajax.open('GET', 'http://www.nasa.gov', true); ajax.onreadystatechange = function(evt) { if(ajax.readyState == 4) { if (ajax.status == 200) { window.dump(":)\n"); } else { window.dump(":(\n"); } } } ajax.send(null); } } ajax.status always returning 0, no matter which site it is, no matter what is the actual return code. I say actual, because ajax.statusText returning correct value, eg OK or Redirecting... ajax.readyState also returns proper values and 4 at the end.

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• Is it a good design to return value by parameter?

  - by aztack

  bool is_something_ok(int param,SomeStruct* p) { bool is_ok = false; // check if is_ok if(is_ok) // set p to some valid value else // set p to NULL return is_ok; } this function return true and set p to a valid value if "something is ok" otherwise return false and set p to NULL Is that a good or bad design? personally, i feel uncomfortable when i use it. If there is no document and comment, i really don know how to use it. BTW:Is there some authoritative book/article about API design?

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• Question about custom events

  - by Malfist

  I'm making custom events for C# and sometimes it isn't working. This is how I'm making the event happen: private bool isDoorOpen; public bool IsDoorOpen { get { return isDoorOpen;} private set { isDoorOpen = value; DoorsChangeState(this, null);} } And these are the event declarations: //events public delegate void ChangedEventHandler(Elevator sender, EventArgs e); public event ChangedEventHandler PositionChanged; public event ChangedEventHandler DirectionChanged; public event ChangedEventHandler BreaksChangeState; public event ChangedEventHandler DoorsChangeState; This works as long as there are methods attached to the events, but if there isn't, it throws a null ref exception. What am I doing wrong?

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• I was making this program and the server wont send to the client

  - by crstin

  void CApplication::SendData( const char pBuffer[] ) { if( pBuffer == NULL ) { Log()->Write( ELogMessageType_ERROR, "Cannot send NULL message."); return; } // calculate the size of that data unsigned long messageSize = strlen( pBuffer ); // fix our byte ordering messageSize = htonl( messageSize ); if( isServer == true ) { for( unsigned int i = ESocket_CLIENT0; i < ESocket_MAX; ++i ) { // send the message size if( m_Socket[ i ] > 0 ) { if( send( m_Socket[ i ], (char*)&messageSize, sizeof( messageSize ), 0 ) == SOCKET_ERROR ) { Log()->Write( ELogMessageType_ERROR, "[Application] Send error: %i to socket %i", WSAGetLastError(), m_Socket[ i ] ); continue; } // fix our message size back to host ordering messageSize = ntohl(messageSize); // send the actual message if( send( m_Socket[ i ], pBuffer, messageSize, 0 ) == SOCKET_ERROR ) { Log()->Write( ELogMessageType_ERROR, "[Application] Send error: %i to socket %i", WSAGetLastError(), m_Socket[ i ] ); continue; } Log()->Write( ELogMessageType_MESSAGE, "[Application] SEND: %s", pBuffer ); } } }

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• Extending struts 2 "property" data tag

  - by John B.

  Hi, We are currently developing a project with Struts2. We have a module on which we display a large amount of data on read-only fields from a group of beans via the "property" Struts 2 data tag (i.e. <s:property value="aBeanProperty" /) on a jsp file. In some cases most of the fields might come empty, so a blank is being displayed on screen. Our customer is now requesting us to display default string (i.e. "N/A") whenever a property comes empty, so that it is displayed in place of the blank spaces currently shown. We are looking for a way to achieve this in a clean and maintainable way. The 'property' tag comes with a 'default' attribute on which one can define a default value in cases when the accessed property comes as null. However, most of our properties are empty strings, therefore it does not work in our case. Another solution we are thinking of is to define a base class for all of our beans, and define a util method which will validate if a string is null or empty and then return the default value. Then we would call this method from each bean getter. And yes this would be tiresome and kind of ugly :), therefore we are holding out on this one in case of a better solution. Now, we have in mind a solution which we think would be the best but have not had luck on how implement it. We are planning on extending the 'property' tag some way, defining a new 'default' attribute so that besides working on null properties, it also do so on empty strings ("", " ", etc). Therefore we would only need to replace the original s:property tag with our new custom tag, and the desired result would be achieved without touching java code. Do you have an idea on how to do this? Also, any other clever solution (maybe some sort of design pattern?) on how to default the values of a large amount of property beans are welcome too! (Or maybe, even there might be some tag that does this already in Struts2??) Thanks in advance.

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• Guidance on using drop in DLLs

  - by Scott Chamberlain

  I have been giving the task to rewrite a internal utility in .net for my work. One of program requirements the new system has is have a dll that implements a set of interfaces and have the program call the DLL. Now this dll will be changed out a lot per deployment. My question is what is the best way to do it from a development standpoint? Do I add a template DLL (one that only has the interfaces but no implementation) to the project references like I would do any other dll that I would use. Or do I need to use somthing like this every time I want to use code from the dll? var DropIn = System.Reflection.Assembly.LoadFrom("DropInDll.dll"); var getActions = DropIn.GetType("Main").GetMethod("GetActions"); List<IAction> ActionList = (List<IAction>)getActions.Invoke(null, null);

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• singleton pattern in java- lazy Intialization

  - by flash

  public static MySingleton getInstance() { if (_instance==null) { synchronized (MySingleton.class) { _instance = new MySingleton(); } } return _instance; } 1.is there a flaw with the above implementation of the getInstance method? 2.What is the difference between the two implementations.? public static synchronized MySingleton getInstance() { if (_instance==null) { _instance = new MySingleton(); } return _instance; } I have seen a lot of answers on the singleton pattern in stackoverflow but the question I have posted is to know mainly difference of 'synchronize' at method and block level in this particular case.

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• sql .................................... [closed]

  - by sagar

  create table tony ( id int(10) NOT NULL,name varchar(20),dob DATE,primary key(id) ); is it right query

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• How to change Session for only one route in asp.net mvc?

  - by denis_n

  How to handle Application_BeginRequest using a custom filter in asp.net mvc? I want to restore session only for one route (~/my-url). It would be cool, if I could create a custom filter and handle that. protected void Application_BeginRequest(object sender, EventArgs e) { var context = HttpContext.Current; if (string.Equals("~/my-url", context.Request.AppRelativeCurrentExecutionFilePath, StringComparison.OrdinalIgnoreCase)) { string sessionId = context.Request.Form["sessionId"]; if (sessionId != null) { HttpCookie cookie = context.Request.Cookies.Get("ASP.NET_SessionId"); if (cookie == null) { cookie = new HttpCookie("ASP.NET_SessionId"); } cookie.Value = sessionId; context.Request.Cookies.Set(cookie); } }

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• .NET Garbage Collection behavior (with DataTable)

  - by gmac

  I am wonder why after creating a very simple DataTable and then setting it to null why Garbage Collection does not clear out all the memory used by that DataTable. Here is an example. The variable Before should be equal to Removed but it is not. { long Before = 0, After = 0, Removed = 0, Collected = 0; Before = GC.GetTotalMemory(true); DataTable dt = GetSomeDataTableFromSql(); After = GC.GetTotalMemory(true); dt = null; Removed = GC.GetTotalMemory(true); GC.Collect(); Collected = GC.GetTotalMemory(true); } Gives the following results. Before = 388116 After = 731248 Removed = 530176 Collected = 530176

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• How to get google app engine logs in C#?

  - by Max

  I am trying to retrieve app engine logs the only result I get is "# next_offset=None", below is my code: internal string GetLogs() { string result = _connection.Get("/api/request_logs", GetPostParameters(null)); return result; } private Dictionary<string, string> GetPostParameters(Dictionary<string, string> customParameters) { Dictionary<string, string> parameters = new Dictionary<string, string>() { { "app_id", _settings.AppId }, { "version", _settings.Version.ToString() } }; if (customParameters != null) { foreach (string key in customParameters.Keys) { if (parameters.ContainsKey(key)) { parameters[key] = customParameters[key]; } else { parameters.Add(key, customParameters[key]); } } } return parameters; }

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• Can MySQL automatically specify `_utf8` for inserts to UTF-8 columns?

  - by Neil

  I have a table like this, where one column is latin1, the other is UTF-8: Create Table: CREATE TABLE `names` ( `name_english` varchar(255) character NOT NULL, `name_chinese` varchar(255) character set utf8 default NULL, ) ENGINE=MyISAM DEFAULT CHARSET=latin1 When I do an insert, I have to type _utf8 before values being inserted into UTF-8 columns: insert into names (name_english = "hooey", name_chinese = _utf8 "??"); However, since MySQL should know that name_chinese is a UTF-8 column, it should be able to know to use _utf8 automatically. Is there any way to tell MySQL to use _utf8 automatically, so when I'm programatically making prepared statements, I don't have to worry about including it with the right parameters?

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• Why is there garbage in my TCHAR, even after ZeroMemory()?

  - by samoz

  I have inherited the following line of code: TCHAR temp[300]; GetModuleFileName(NULL, temp, 300); However, this fails as the first 3 bytes are filled with garbage values (always the same ones though, -128, -13, 23, in that order). I said, well fine and changed it to: TCHAR temp[300]; ZeroMemory(temp, 300); GetModuleFileName(NULL, temp, 300); but the garbage values persisted! Can someone explain what is going on and how to fix it?

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• Queues And Wait Handles in C#

  - by Michael Covelli

  I've had the following code in my application for some years and have never seen an issue from it. while ((PendingOrders.Count > 0) || (WaitHandle.WaitAny(CommandEventArr) != 1)) { lock (PendingOrders) { if (PendingOrders.Count > 0) { fbo = PendingOrders.Dequeue(); } else { fbo = null; } } // Do Some Work if fbo is != null } Where CommandEventArr is made up of the NewOrderEvent (an auto reset event) and the ExitEvent (a manual reset event). But I just realized today that its not thread safe at all. If this thread gets interrupted right after the first (PendingOrder.Count 0) check has returned false. And then the other thread both enqueues an order and sets the NewOrderEvent before I get a chance to wait on it, the body of the while loop will never run. What's the usual pattern used with a Queue and an AutoResetEvent to fix this and do what I'm trying to do with the code above?

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• VS JavaScript intellisense with paramaters

  - by TonyB

  here is some sample javascript: SomeObjectType = function() { } SomeObjectType.prototype = { field1: null, field2: null } SomeOtherObject = function() { } SomeOtherObject.prototype = { doSomething: function(val) { /// <param name="val" type="SomeObjectType"></param> var val2 = new SomeObjectType(); //val2. shows intellisense correctly //val1. does NOT } } Shouldn't visual studio be giving me intellisence when i do "val." inside the "doSomething" function? I would expect it to give me field1 and field2 as options, but it doesn't. I DO get field1 and field2 if I type "val2." so intellisence works when I create a new object of the same type that I specify in the param comment. Any ideas what I am doing wrong or is this just not supported?

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• onPerformSync() is not triggered after ContentResolver.requestSync() call

  - by mark

  I am trying to implement sync adaptor, I have followed This guide. But onPerformSync() is not triggered after ContentResolver.requestSync() call . I have also tried some other tutorials and tried to run their code, but still same issue. Please tell me does I need to do some extra configuration for this. My code of triggering sync operation is as folows : Account newAccount = new Account(GlobalInfo.ACCOUNT, GlobalInfo.ACCOUNT_TYPE); AccountManager accountManager = (AccountManager) this.getSystemService(ACCOUNT_SERVICE); accountManager.addAccountExplicitly(newAccount, null, null); ContentResolver.requestSync(newAccount,GlobalInfo.AUTHORITY, Bundle.EMPTY); Please guide me to solve this issue. EDIT : Accounted created (in Settings - Accounts and Sync settings) by above code showing sync is off

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• using both layout-land and onConfigurationChanged()

  - by joe

  I just want to change Layout when the device has been rotated. but I've found that onConfigurationChanged() must call onCreate() again using setContentView with separated layout named of *_land.xml if(getActivity().getWindowManager().getDefaultDisplay(). getRotation() == Surface.ROTATION_0) view = inflater.inflate(R.layout.fragment_layout, null); else view = inflater.inflate(R.layout.fragment_layout_land, null); Project is too big and there are many codes to fix If onCreate again without finish(). I'd like somebody help this. Thank you. - onConfigurationChanged concept is keep layout I think

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• Waiting on threads

  - by Paul Reiners

  I have a method that contains the following (Java) code: doSomeThings(); doSomeOtherThings(); doSomeThings() creates some threads, each of which will run for only a finite amount of time. The problem is that I don't want doSomeOtherThings() to be called until all the threads launched by doSomeThings() are finished. (Also doSomeThings() will call methods that may launch new threads and so on. I don't want to execute doSomeOtherThings() until all these threads have finished.) This is because doSomeThings(), among other things will set myObject to null, while doSomeOtherThings() calls myObject.myMethod() and I do not want myObject to be null at that time. Is there some standard way of doing this kind of thing (in Java)?

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