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  • Recognition source of event in PyQT

    - by xTrol
    Hi, I`m starting with PyQt4 and right now I have a problem with events. I have one main class let say MainWindow. MainWindow has a list of buttons of type ButtonX (inherence form QPushButton). I would like to achieve one of 2 solutions (depends which is easier). 1) After click one of the button from the list I would like to run a one method of MainWindow. I would like to be able to read a source of event there (recognize clicked button) 2) Second solution is to run a method defined in ButtonX class. What I tried is: QtCore.QObject.connect(self.getButton(0, 0), QtCore.SIGNAL("clicked()"), self.getButton(0, 0).buttonMethod()) QtCore.QObject.connect(self.getButton(0, 0), QtCore.SIGNAL("clicked()"), self.getButton(0, 0), QtCore.SLOT("incrementValue()")) and even this line occure suspend Python interpreter QtCore.QObject.connect(self.getButton(0, 0), QtCore.SIGNAL("clicked()"), self.getButton(0, 0), QtCore.SLOT("incrementValue"))

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  • How to use a class's type as the type argument for an inherited collection property in C#

    - by Edelweiss Peimann
    I am trying to create a representation of various types of card that inherit from a generic card class and which all contain references to their owning decks. I tried re-declaring them, as suggested here, but it still won't convert to the specific card type. The code I currently have is as such: public class Deck<T> : List<T> where T : Card { void Shuffle() { throw new NotImplementedException("Shuffle not yet implemented."); } } public class Card { public Deck<Card> OwningDeck { get; set; } } public class FooCard : Card { public Deck<FooCard> OwningDeck { get { return (Deck<FooCard>)base.OwningDeck; } set { OwningDeck = value; } } } The compile-time error I am getting: Error 2 Cannot convert type 'Game.Cards.Deck' to 'Game.Cards.Deck' And a warning suggesting I use a new operator to specify that the hiding is intentional. Would doing so be a violation of convention? Is there a better way? My question to stackoverflow is this: Can what I am trying to do be done elegantly in the .NET type system? If so, can some examples be provided?

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  • Loop throught form inputs

    - by Victor
    I have a form with lots of inputs. I want to get each id and value and then put them in $.load method. I tried this: $("#form input").each(function() { var name = $(this).attr("id"); var value = $(this).attr("value"); $.extend(params, { name, value }); }); and then use $.load("script.php", params); But obviously it doesn't work. In params I have only one element "name". And I'm not sure I should use extend method too.

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  • ASP.NET: ModalPopupExtender prevents button click event from firing

    - by C. Griffin
    Here is what I'm trying to do: Click a button on my page, which in turn makes (2) things happen: Display a ModalPopup to prevent the user from pressing any buttons or changing values Call my code behind method, hiding the ModalPopup when finished Here is the ASP markup: <asp:UpdatePanel ID="UpdatePanel2" runat="server" ChildrenAsTriggers="true" UpdateMode="Always"> <Triggers> <asp:AsyncPostBackTrigger ControlID="btnSaveData" EventName="Click" /> </Triggers> <ContentTemplate> <asp:Panel ID="pnlHidden" runat="server" style="display: none;"> <div> <h1>Saving...</h1> </div> </asp:Panel> <cc1:ModalPopupExtender ID="modalPopup" BackgroundCssClass="modalBackground" runat="server" TargetControlID="btnSaveData" PopupControlID="pnlHidden"> </cc1:ModalPopupExtender> <asp:Button ID="btnSaveData" runat="server" Text="Save Data" OnClick="btnSaveData_Click" /> </ContentTemplate> </asp:UpdatePanel> Now, here is my code behind C# code: protected void btnSaveData_Click(object sender, EventArgs e) { UpdateUserData(GetLoggedInUser()); modalPopup.Enabled = false; } Why doesn't this work? The ModalPopup displays perfectly, but the btnSaveData_Click event NEVER fires.

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  • iPhone: Setup static content of UITableView

    - by Martin
    This guide from apple https://developer.apple.com/iphone/prerelease/library/documentation/UserExperience/Conceptual/TableView_iPhone/TableViewCells/TableViewCells.html (you need login) explains how to use "The Technique for Static Row Content" to use Interface Builder to setup the cells in a tableview. I have some cells with different heights in my tableview. Without using the heightForRowAtIndexPath method everything get messed up. Do I still need to use this method or can I in some way setup the height of the cells inside the IB as I created them there? Also when using the "The Technique for Static Row Content" from the guide you still need to use the cellForRowAtIndexPath to setup the cells even if they are created in IB. I would like to setup the full layout of the tableview with all cells in IB (drag the cells right into the tableview), is that possible in some way? Thanks!

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  • How to remove duplicate line in a file

    - by Abs
    Hi I'm using the below method to write to a file from the Jtextarea and I call this method every 30 second within a Timer but instead to add only new line in file it rewrite the entire lines contained in Jtextarea so then I have duplicate lines. I want to avoid this and update the file just with new lines. Could you help me please. public void loger() { FileWriter writer = null; try { writer = new FileWriter("MBM_Log_"+date()+".txt" , true); textArea.write(writer); } catch (IOException exception) { System.err.println("log error"); exception.printStackTrace(); } finally { if (writer != null) { try { writer.close(); } catch (IOException exception) { System.err.println("Error closing writer"); exception.printStackTrace(); } } } }

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  • How can i do the same thing with Gallery in Android

    - by Maxood
    I am navigating images with the clicks of next and previous buttons.Here is my code: package com.myapps.imagegallery; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.ImageView; import android.widget.TextView; import android.widget.Toast; public class ImageGallery extends Activity { /** Called when the activity is first created. */ int imgs[] = {R.drawable.bluehills,R.drawable.lilies,R.drawable.sunset,R.drawable.winter}; String desc[] = {"Blue Hills", "Lillies", "Sunset", "Winter" }; int counter=0; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); final ImageView imgView = (ImageView)findViewById(R.id.ImageView01); imgView.setImageResource(imgs[counter]); final TextView tvDesc = (TextView)findViewById(R.id.tvDesc); Button btnNext = (Button)findViewById(R.id.btnNext); btnNext.setOnClickListener(new View.OnClickListener(){ @Override public void onClick(View arg0) { try{ // TODO Auto-generated method stub if (counter < desc.length -1) counter++; imgView.setImageResource(imgs[counter]); tvDesc.setText(desc[counter]); }catch(Exception e) { Toast.makeText(ImageGallery.this, e.toString(), Toast.LENGTH_SHORT).show(); } } }); Button btnPrev = (Button)findViewById(R.id.btnPre); btnPrev.setOnClickListener(new View.OnClickListener(){ @Override public void onClick(View arg0) { // TODO Auto-generated method stub try{ // TODO Auto-generated method stub if (counter > 0) counter--; imgView.setImageResource(imgs[counter]); tvDesc.setText(desc[counter]); }catch(Exception e) { Toast.makeText(ImageGallery.this, e.toString(), Toast.LENGTH_SHORT).show(); } }}); } } <?xml version="1.0" encoding="utf-8"?> <AbsoluteLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <ImageView android:id="@+id/ImageView01" android:layout_x="70dip" android:layout_width="200px" android:layout_height="200px" android:layout_y="90dip" > </ImageView> <TextView android:id="@+id/tvDesc" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/hello" android:layout_x="90px" android:layout_y="300px" /> <Button android:layout_x="47dip" android:layout_height="wrap_content" android:text="Previous" android:layout_width="100px" android:id="@+id/btnPre" android:layout_y="341dip"> </Button> <Button android:layout_x="190dip" android:layout_height="wrap_content" android:text="Next" android:layout_width="100px" android:id="@+id/btnNext" android:layout_y="341dip"> </Button> </AbsoluteLayout>

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  • C# Property Access vs Interface Implementation

    - by ehdv
    I'm writing a class to represent a Pivot Collection, the root object recognized by Pivot. A Collection has several attributes, a list of facet categories (each represented by a FacetCategory object) and a list of items (each represented by a PivotItem object). Therefore, an extremely simplified Collection reads: public class Collection { private List<FacetCategory> categories; private List<PivotItem> items; // other attributes } What I'm unsure of is how to properly grant access to those two lists. Because declaration order of both facet categories and items is visible to the user, I can't use sets, but the class also shouldn't allow duplicate categories or items. Furthermore, I'd like to make the Collection object as easy to use as possible. So my choices are: Have Collection implement IList<PivotItem> and have accessor methods for FacetCategory: In this case, one would add an item to Collection foo by writing foo.Add(bar). This works, but since a Collection is equally both kinds of list making it only pass as a list for one type (category or item) seems like a subpar solution. Create nested wrapper classes for List (CategoryList and ItemList). This has the advantage of making a consistent interface but the downside is that these properties would no longer be able to serve as lists (because I need to override the non-virtual Add method I have to implement IList rather than subclass List. Implicit casting wouldn't work because that would return the Add method to its normal behavior. Also, for reasons I can't figure out, IList is missing an AddRange method... public class Collection { private class CategoryList: IList<FacetCategory> { // ... } private readonly CategoryList categories = new CategoryList(); private readonly ItemList items = new ItemList(); public CategoryList FacetCategories { get { return categories; } set { categories.Clear(); categories.AddRange(value); } } public ItemList Items { get { return items; } set { items.Clear(); items.AddRange(value); } } } Finally, the third option is to combine options one and two, so that Collection implements IList<PivotItem> and has a property FacetCategories. Question: Which of these three is most appropriate, and why?

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  • JNI cached jclass global reference variables being garbage collected?

    - by bubbadoughball
    I'm working in the JNI Invocation API, calling into Java from C. I have some upfront initialization to cache 30+ Java classes into global references. The results of FindClass are passed into NewGlobalRef to acquire a global reference to the class. I'm caching these class variables to reuse them later. I have 30+ global references to classes (and 30+ global methodIDs for the class constructors). In the following sample, I've removed exception handling as well as JNI invocation for the purpose of shortening the code snippet. My working code has exception checks after every JNI call and I'm running with -Xcheck:jni. Here's the snippet: jclass aClass; jclass bClass; jmethodID aCtor; jmethodID bCtor; void getGlobalRef(const char* clazz, jclass* globalClass) { jclass local = (*jenv)->FindClass(jenv,clazz); if (local) { *globalClass = (jclass) (*jenv)->NewGlobalRef(jenv,local); (*jenv)->DeleteLocalRef(jenv,local); } } methodID getMethodID(jclass clazz, const char* method, const char* sig) { return (*jenv)->GetMethodID(jenv,clazz,method,sig); } void initializeJNI() { getGlobalRef("MyProj/Testclass1", &aclass); getGlobalRef("MyProj/Testclass2", &bclass); . . aCtor = getMethodID(aclass,"<init>","()V"); bCtor = getMethodID(bclass,"<init>","(I)V"); } The initializeJNI() function sets the global references for jclasses and method IDs for constructors as well as some jfieldID's and some initialization of C data structures. After initialization, when I call into a JNI function using some of the cached jclasses and ctor jmethodIDs, I get a bad global or local reference calling reported from the -Xcheck:jni. In gdb, I break at the last line of initializeJNI(), and print all jclasses and jmethodIDs and the ones causing problems look to have been turned into garbage or garbage-collected (i.e. 0x00 or 0x06). Is it possible for global references to be gc'ed? Any suggestions?

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  • Enable Query Strings in Code Igniter

    - by tarnfeld
    Hey, I am trying to implement Twitter's OAuth into my Code Igniter web application at which the callback URL is /auth/ so once you have authenticated with Twitter you are taken to /auth/?oauth_token=SOME-TOKEN. I want to keep the nice clean URL's the framework provides using the /controller/method/ style of URL but I want to enable query strings as well, there will only ever be one name of the data oauth_token so it's ok if it has to be hard coded. Any ideas? I have tried tons of the things people are saying to do, but none work :( PS: I'm using the .htaccess method of URL rewriting.

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  • Java HashSet is allowing dupes; problem with comparable?

    - by IVR Avenger
    Hi, all. I've got a class, "Accumulator", that implements the Comparable compareTo method, and I'm trying to put these objects into a HashSet. When I add() to the HashSet, I don't see any activity in my compareTo method in the debugger, regardless of where I set my breakpoints. Additionally, when I'm done with the add()s, I see several duplicates within the Set. What am I screwing up, here; why is it not Comparing, and therefore, allowing the dupes? Thanks, IVR Avenger

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  • How to get methods list in scala

    - by skyde
    In language like python and ruby to ask the language what index-related methods its string class supports (which methods’ names contain the word “index”) you can do “”.methods.sort.grep /index/i And in java List results = new ArrayList(); Method[] methods = String.class.getMethods(); for (int i = 0; i < methods.length; i++) { Method m = methods[i]; if (m.getName().toLowerCase().indexOf(“index”) != -1) { results.add(m.getName()); } } String[] names = (String[]) results.toArray(); Arrays.sort(names); return names; How would you do the same thing in Scala?

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  • Google Docs iphone library error reporting

    - by phil harris
    I'm in the process of adding a Google Docs interface to my iPhone app, and I'm largely following the example in the GoogleDocs.m file from Tom Saxton's example app. The objective-c library I'm using is from http://code.google.com/p/gdata-objectivec-client/wiki/GDataObjCIntroduction The library file used is from gdata-objectivec-client-1.10.0.zip. This service:username:password method is a slight variant of the one found in the Saxton file GoogleDocs.m starting at line 351: - (void)service:(NSString *)username password:(NSString *)password { if(service == nil) { service = [[[GDataServiceGoogleDocs alloc] init] autorelease]; [service setUserAgent:s_strUserAgent]; [service setShouldCacheDatedData:NO]; [service setServiceShouldFollowNextLinks:NO]; (void)[service authenticateWithDelegate:self didAuthenticateSelector:@selector(ticket:authenticatedWithError:)]; } // update the username/password each time the service is requested if (username != nil && [username length] && password != nil && [password length]) [service setUserCredentialsWithUsername:username password:password]; else [service setUserCredentialsWithUsername:nil password:nil]; } // associated callback for service:username:password: method - (void)ticket:(GDataServiceTicket *)ticket authenticatedWithError:(NSError *)error { NSLog(@"%@",@"authenticatedWithError called"); if(error == nil) [self selectBackupRestore]; else { NSLog(@"error code(%d)", [error code]); NSLog(@"error domain(%d)", [error domain]); NSLog(@"localizedDescription(%@)", error.localizedDescription); NSLog(@"localizedFailureReason(%@)", error.localizedFailureReason); NSLog(@"localizedRecoveryOptions(%@)", error.localizedRecoveryOptions); NSLog(@"localizedRecoverySuggestion(%@)", error.localizedRecoverySuggestion); } } Please note the service:username:password method and the callback compile and run fine. The problem is that the callback is passing a non-nil NSError object. I added an NSLog() for every error reporting attribute of NSError and the (Xcode) log output of a test run is below. [Session started at 2010-05-27 12:27:16 -0700.] 2010-05-27 12:27:38.778 iFilebox[74596:207] authenticatedWithError called 2010-05-27 12:27:38.779 iFilebox[74596:207] error code(-1) 2010-05-27 12:27:38.780 iFilebox[74596:207] error domain(499324) 2010-05-27 12:27:38.781 iFilebox[74596:207] localizedDescription(Operation could not be completed. (com.google.GDataServiceDomain error -1.)) 2010-05-27 12:27:38.782 iFilebox[74596:207] localizedFailureReason((null)) 2010-05-27 12:27:38.782 iFilebox[74596:207] localizedRecoveryOptions((null)) 2010-05-27 12:27:38.783 iFilebox[74596:207] localizedRecoverySuggestion((null)) My essential question is in the error reporting. I was hoping the localizedDescription would be more specific of the error. All I get for the error code value is -1, and the only description of the error is "Operation could not be completed. (com.google.GDataServiceDomain error -1.". Not very helpful. Does anyone know what a GDataServiceDomain error -1 is? Where can I find a full list of all error codes returned, and a description of what they mean?

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  • Get the ID of a Child in a cascade="all" relationship, while adding it to a collection, in Hibernate

    - by Marco
    Hi, i have two Entities, "Parent" and "Child", that are linked through a bidirectional one-to-many relationship with the cascade attribute set to "all". When adding a Child object to the Parent children collection using the code below, i can't get the ID of the persisted child until i commit the transaction: Parent p = (Parent) session.load(Parent.class, pid); Child c = new Child(); p.addChild(c); // "c" hasn't an ID (is always zero) However, when i persist a child entity by explicitly calling the session.save() method, the ID is created and set immediately, even if the transaction hasn't been committed: Child c = new Child(); session.save(c); // "c" has an ID Is there a way to get the ID of the child entity immediately without calling the session.save() method? Thanks

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  • Does Google Analytics have peformance overhead?

    - by Mohit Nanda
    To what extent does Google Analytics impact performance? I'm looking for the following: Benchmarks (including response times/pageload times et al) Links or results to similar benchmarks One (possible) method of testing Google Analytics (GA) on your site: Serve ga.js (the Google Analytics JavaScript file) from your own server. Update from Google Daily (test 1) and Weekly (test 2). I would be interested to see how this reduces the communication between the client webserver and the GA server. Has anyone conducted any of these tests? If so, can you provide your results? If not, does anyone have a better method for testing the performance hit (or lack thereof) for using GA?

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  • How do I create a simple seach box with a submit button to bring back a result set in MVC?

    - by RJ
    I am very new to MVC and just learning the basics. I have been following along in Nerd Dinner and used the demo as a way to create my own app. I have created a page that lists out some food items with calories, fat, protein,etc... (http://rjsfitness.net/CalorieList) This is one of my own personal sites that I set up to test out MVC. I got a lot of it working but I am stuck on the textbox with a search button. My view page has this code for the search: <form action="/CalorieList/Search" method="post" id="searchForm"> <input type="text" name="searchTerm" id="searchTerm" value="" size="10" maxlength ="30" /> <input type ="submit" value="Search" /> </form> My global.asax has this code for the routing: routes.MapRoute( "Search", // Route name "CalorieList/Search/{searchTerm}", // URL with parameters new { controller = "CalorieList", action = "Search", search = "" } // Parameter defaults ); My Controller has this code: public ActionResult Index(int? page) { const int pageSize = 10; //load a list with the calorie list var calorieLists = calorieListRepository.GetAllCalorieLists(); //var paginatedCalorieLists = calorieLists.Skip((page ?? 0) * pageSize).Take(pageSize).ToList(); var paginatedCalorieLists = new PaginatedList<CalorieList>(calorieLists, page ?? 0, pageSize); return View("Index", paginatedCalorieLists); } public ActionResult Search(String searchTerm) { const int pageSize = 100; int? page = 0; var calorieLists = calorieListRepository.GetCalorieListsBySearch(searchTerm); var paginatedCalorieLists = new PaginatedList<CalorieList>(calorieLists, page ?? 0, pageSize); return View("Index", paginatedCalorieLists); } return View("Index", paginatedCalorieLists); } When I enter a value and click the button, the Index method fires instead of the Seach method in the controller and I get the full list again. If I manually type the url (http://rjsfitness.net/CalorieList/Search/choc) I get the right listing. Why isn't my button click using the right routing and giving me the search results?

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  • [jscript] Good (better) substition for setInterval or setTimeout

    - by riffnl
    I've got a masterpage with some nice UI (jQuery) features. One of these options is interefering with my embedded YouTube (or other alike-) objects. On each, in this case, setInterval event the embedded video stops displaying new frames (for like a second). More detail: I've got a "polaroid" gallery (in the header) with only 5 100x100 images in it (test: preloading has no effect on performance) and my gallery will show or hide them (fade-in / fade-out) after a period of time. (test: non-animated display:hide or display:block has no effect on performance). After some testing and I've come to the conclusion that it isn't the "animated" showing or hiding of the pictures, but it's the interval itself (- since altering to display:hide or block had the same result). Perhaps it is my "gallery" "function" on itself ... function poladroid() { if (!galleryHasFocus) { if (galleryMax >= 0) { galleryCurrent++; if (galleryCurrent > galleryMax) { galleryCurrent = 0; showPictures = !showPictures; } if (showPictures) { $('#pic-' + galleryCurrent.toString()).show("slow"); } else { $('#pic-' + galleryCurrent.toString()).hide("slow"); } } } if (!intervalSet) { window.setInterval("poladroid()", 3000); intervalSet = true; } } It's not like my function is doing really awkward stuff is it? So, I was thinking I needed a more "loose" interval function.. but is there an option for it?

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  • Display values inside a JList -

    - by sharon Hwk
    I have a method that returns a HashMap, and is defined as follows; public HashMap<Integer, Animal> allAnimal(){ return returnsAHashMap; } Animal will have the following values in its class: public Animal{ int animalID; String animalName; // i have declared getters/setters } I have a GUI screen which has a JList and it's defined as: l = new JList(); l.setModel(new AbstractListModel() { String[] v = new String[] {"animal id 1", "2", "3"}; public int getSize() { return v.length; } public Object getElementAt(int index) { return v[index]; } }); What I want to do is to display the AnimalID's in the JList. I need to find a way to call the allAnimal() method and display all its Animal Id's in the JList. How can i do this ?

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  • Constructor invokation returned null: what to do?

    - by strager
    I have code which looks like: private static DirectiveNode CreateInstance(Type nodeType, DirectiveInfo info) { var ctor = nodeType.GetConstructor(new[] { typeof(DirectiveInfo) }); if(ctor == null) { throw new MissingMethodException(nodeType.FullName, "ctor"); } var node = ctor.Invoke(new[] { info }) as DirectiveNode; if(node == null) { // ???; } return node; } I am looking for what to do (e.g. what type of exception to throw) when the Invoke method returns something which isn't a DirectiveNode or when it returns null (indicated by // ??? above). (By the method's contract, nodeType will always describe a subclass of DirectiveNode.) I am not sure when calling a constructor would return null, so I am not sure if I should handle anything at all, but I still want to be on the safe side and throw an exception if something goes wrong.

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  • Passing Auth to API calls with Web Service References

    - by coffeeaddict
    I am new to web services. The last time I dealt with SOAP was when I created a bunch of wrapper classes that sent requests and received responses back per some response objects/classes I had created. So I had an object to send certain API requests and likewise a set of objects to hold the response back as an object so I could utilize that 3rd party API. Then someone came to me and said why not just use the wsdl and a web service. Ok, so today I went and created a "Service Reference". I see that this is what's called a "Proxy Class". You just instantiate an instance of this and then walla you have access to all the methods from the wsdl. But this leaves me with auth questions. Back when I created my own classes manually, I had a class which exposed properties that I would set then access for things like signature, username, password that got sent along with the Http request that were required by whatever 3rd party API I was using to make API calls. But then with using a Service Reference, how then would I pass this information just like I had done in my custom classes? For instance I'm going to be working with the PayPal API. It requires you to send a signature and a few other pieces of information like username and password. // Determins if API call needs to use a session based URI string requestURI = UseAuthURI == true ? _requestURIAuthBased + aSessionID : _requestURI; byte[] data = XmlUtil.DocumentToBytes(doc); // Create the atual Request instance HttpWebRequest request = CreateWebRequest(requestURI, data.Length); So how do I pass username, password, signature, etc. when using web service references for each method call? Is it as simple as specifying it as a param to the method or do you use the .Credentials and .URL methods of your proxy class object? It seems to me Credentials means windows credentials but I could be wrong. Is it limited to that or can you use that to specify those required header values that PayPal expects with each method call/API request?

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  • Is this a valid pattern for raising events in C#?

    - by Will Vousden
    Update: For the benefit of anyone reading this, since .NET 4, the lock is unnecessary due to changes in synchronization of auto-generated events, so I just use this now: public static void Raise<T>(this EventHandler<T> handler, object sender, T e) where T : EventArgs { if (handler != null) { handlerCopy(sender, e); } } And to raise it: SomeEvent.Raise(this, new FooEventArgs()); Having been reading one of Jon Skeet's articles on multithreading, I've tried to encapsulate the approach he advocates to raising an event in an extension method like so (with a similar generic version): public static void Raise(this EventHandler handler, object @lock, object sender, EventArgs e) { EventHandler handlerCopy; lock (@lock) { handlerCopy = handler; } if (handlerCopy != null) { handlerCopy(sender, e); } } This can then be called like so: protected virtual void OnSomeEvent(EventArgs e) { this.someEvent.Raise(this.eventLock, this, e); } Are there any problems with doing this? Also, I'm a little confused about the necessity of the lock in the first place. As I understand it, the delegate is copied in the example in the article to avoid the possibility of it changing (and becoming null) between the null check and the delegate call. However, I was under the impression that access/assignment of this kind is atomic, so why is the lock necessary? Update: With regards to Mark Simpson's comment below, I threw together a test: static class Program { private static Action foo; private static Action bar; private static Action test; static void Main(string[] args) { foo = () => Console.WriteLine("Foo"); bar = () => Console.WriteLine("Bar"); test += foo; test += bar; test.Test(); Console.ReadKey(true); } public static void Test(this Action action) { action(); test -= foo; Console.WriteLine(); action(); } } This outputs: Foo Bar Foo Bar This illustrates that the delegate parameter to the method (action) does not mirror the argument that was passed into it (test), which is kind of expected, I guess. My question is will this affect the validity of the lock in the context of my Raise extension method? Update: Here is the code I'm now using. It's not quite as elegant as I'd have liked, but it seems to work: public static void Raise<T>(this object sender, ref EventHandler<T> handler, object eventLock, T e) where T : EventArgs { EventHandler<T> copy; lock (eventLock) { copy = handler; } if (copy != null) { copy(sender, e); } }

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  • Enable editing does not call didSelectRowAtIndexPath ??

    - by elementsense
    Hi I have a UITableViewController where the user should be able to edit the items. In order to enable editing i use this : self.navigationItem.rightBarButtonItem = self.editButtonItem; And for everyone, how does not know where self.editButtonItem comes from, it is predefined by the SDK. So, now when I press on any item, this method is called : - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath but as soon as I hit the edit button and while editing is active, this method does not seemed to be called. Any idea what I missing ? This is the rest of the code that is related to editing : // Override to support conditional editing of the table view. - (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath { // Return NO if you do not want the specified item to be editable. return YES; } - (UITableViewCellEditingStyle)tableView:(UITableView *)tableView editingStyleForRowAtIndexPath:(NSIndexPath *)indexPath { return UITableViewCellEditingStyleNone; } - (BOOL)tableView:(UITableView *)tableView shouldIndentWhileEditingRowAtIndexPath:(NSIndexPath *)indexPath { return NO; } Thanks for the help. mcb

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  • Is it appropriate to set a value to a "const char *" in the header file

    - by sud
    I have seen people using 2 methods to declare and define char * Medhod-1: The header file has the below const char* COUNTRY_NAME_USA = "USA"; Medhod-2: The header file has the below declaration const char* COUNTRY_NAME_USA; The cpp file has the below defintion : const char* COUNTRY_NAME_USA = "USA"; Is method-2 wrong in some way ? What is the difference between the two ? I understand the difference between "const char * const var" , and "const char * var". If in the above methods if a "const char * const var" is declared and defined in the header as in method 1 will it make sense ?

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