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  • sorting a gridview in class

    - by user175084
    ok i have a project which has many gridview in its pages... now i am sorting the fridveiw using the sorting function like this: protected void GridView1_Sorting(object sender, GridViewSortEventArgs e) { DataTable dt = Session["TaskTable2"] as DataTable; if (dt != null) { //Sort the data. dt.DefaultView.Sort = e.SortExpression + " " + GetSortDirection(e.SortExpression); GridView1.DataSource = Session["TaskTable2"]; GridView1.DataBind(); } } private string GetSortDirection(string column) { // By default, set the sort direction to ascending. string sortDirection2 = "ASC"; // Retrieve the last column that was sorted. string sortExpression2 = ViewState["SortExpression2"] as string; if (sortExpression2 != null) { // Check if the same column is being sorted. // Otherwise, the default value can be returned. if (sortExpression2 == column) { string lastDirection = ViewState["SortDirection2"] as string; if ((lastDirection != null) && (lastDirection == "ASC")) { sortDirection2 = "DESC"; } } } // Save new values in ViewState. ViewState["SortDirection2"] = sortDirection2; ViewState["SortExpression2"] = column; return sortDirection2; } but this code is being repeated in many pages so i tried to put this function in a C# class and try to call it but i get errors.... for starters i get the viewstate error saying :| "viewstate does not exist in the current context" so how do i go about doing this ....?? thanks

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  • Cannot use Java 7 instalation if Java 8 is installed

    - by Sebastien Diot
    I normally still use Java 7 for all my coding projects (it's a company "politics" issue), but I installed Java 8 for one third-party project I am contributing to. Now, it seems I cannot have Java 8 installed in Windows 7 x64, and still use Java 7 by default: C:\>"%JAVA_HOME%\bin\java.exe" -version java version "1.7.0_55" Java(TM) SE Runtime Environment (build 1.7.0_55-b13) Java HotSpot(TM) 64-Bit Server VM (build 24.55-b03, mixed mode) C:\>java.exe -version java version "1.8.0_05" Java(TM) SE Runtime Environment (build 1.8.0_05-b13) Java HotSpot(TM) 64-Bit Server VM (build 25.5-b02, mixed mode) As you can see, JAVA_HOME is completely ignored. I also have Java in the path, using "%JAVA_HOME%\bin", which resolve correctly to Java 7 when I check the path in a DOS box, but it still makes no difference. I checked in the "Java Control Panel" (not sure if this affects the default command-line Java version). Under the "Java" tab, the "View..." button, you get to see "registered" Java versions. I can add all the versions under the "User" tab, but under "System" there is only Java 8, and no way to change it. Am I missing something, or did Oracle just make it impossible to use Java 7, unless I de-install Java 8? I don't want to have to specify the "source" and "target" everywhere, and I don't even know if it is possible for me to specify it everywhere, where Java is used. EDIT: What I did is I de-installed all Java. Then installed the latest Java7 (both 86 and x64), and then the latest Java8 (both 86 and x64). After I did that, I noticed that the x64 JDK was gone. It seems Java8 killed it. So I re-installed the JDK 7 x64, after the JDK 8 x64. Still, JDK7 x64 did not seem to "replace" the "java.exe" which is copied into the "Windows" directory itself (I assume THAT is the problem).

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  • "loading" div automatically appended when using cordova (phonegap)

    - by Vlad Ioffe
    I am using cordova for mobile app development on android platform. I have this html code in www/index.html file: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <meta http-equiv="Content-Language" content="en" /> <script src="cordova-2.2.0.js" type="text/javascript"></script> <script src="jquery/jquery.js" type="text/javascript"></script> <script src="jquery.mobile/jquery.mobile-1.1.0.js" type="text/javascript"></script> <script src="JS/main.js" type="text/javascript"></script> <link rel="stylesheet" href="CSS/main.css"/> </head> <body id="body" class="body"> <div id="box" class="bodyBlack"> </div> </body> </html> I don't know why but when I am running this app (also when just opening on pc browser) i am having this div appended at the bottom of the page: <div ui-loader ui-corner-all ui-body-a ui-loader-default> <span ui-loader ui-corner-all ui-body-a ui-loader-default></span> <h1>loading</h1> Why and from where dose it getting from? how I am preventing it to do so? Thanks!!!

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  • Struts 2 security

    - by Dewfy
    Does Struts 2 has complete solution for simple login task? I have simple declaration in struts.xml: <package namespace="/protected" name="manager" extends="struts-default" > <interceptors> <interceptor-stack name="secure"> <interceptor-ref name="roles"> <param name="allowedRoles">registered</param> </interceptor-ref> </interceptor-stack> </interceptors> <default-action-ref name="pindex"/> <action name="pindex" > <interceptor-ref name="completeStack"/> <interceptor-ref name="secure"/> <result>protected/index.html</result> </action> </package> Accessing to this resource shows only (Forbidden 403). So what should I do on the next step to: Add login page (standart Tomcat declaration on web.xml with <login-config> not works) ? Provide security round trip. Do I need write my own servlet or exists struts2 solutions? Thanks in advance!

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  • Unresolved external symbol error in c++

    - by Crystal
    I am trying to do a simple hw problem involving namespace, static data members and functions. I am getting an unresolved external symbol error Error 1 error LNK2001: unresolved external symbol "private: static double JWong::SavingsAccount::annualInterestRate" (?annualInterestRate@SavingsAccount@JWong@@0NA) SavingsAccount.obj SavingsAccount And I don't see why I am getting this error. Maybe I don't know something about static variables compared to regular data members that is causing this error. Here is my code: SavingsAccount.h file #ifndef JWONG_SAVINGSACCOUNT_H #define JWONG_SAVINGSACCOUNT_H namespace JWong { class SavingsAccount { public: // default constructor SavingsAccount(); // constructor SavingsAccount(double savingsBalance); double getSavingsBalance(); void setSavingsBalance(double savingsBalance); double calculateMonthlyInterest(); // static functions static void modifyInterestRate(double newInterestRate); static double getAnnualInterestRest(); private: double savingsBalance; // static members static double annualInterestRate; }; } #endif SavingsAccount.cpp file #include <iostream> #include "SavingsAccount.h" // default constructor, set savingsBalance to 0 JWong::SavingsAccount::SavingsAccount() : savingsBalance(0) {} // constructor JWong::SavingsAccount::SavingsAccount(double savingsBalance) : savingsBalance(savingsBalance) {} double JWong::SavingsAccount::getSavingsBalance() { return savingsBalance; } void JWong::SavingsAccount::setSavingsBalance(double savingsBalance) { this->savingsBalance = savingsBalance; } // returns monthly interest and sets savingsBalance to new amount double JWong::SavingsAccount::calculateMonthlyInterest() { double monthlyInterest = savingsBalance * SavingsAccount::annualInterestRate / 12; setSavingsBalance(savingsBalance + monthlyInterest); return monthlyInterest; } void JWong::SavingsAccount::modifyInterestRate(double newInterestRate) { SavingsAccount::annualInterestRate = newInterestRate; } double JWong::SavingsAccount::getAnnualInterestRest() { return SavingsAccount::annualInterestRate; }

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  • Save Bitmap image in a location in C#

    - by acadia
    Hello, I have this function to store the bmp image in a desired location as shown below My question is, how do I save the image in C:\temp folder by default, instead of opening the filedialog box? I want to specify sd.fileName=picname+".bmp" and store it in c:\temp by default. I tried to specify Thanks for your help in advance. I tried to public static bool SaveDIBAs( string picname, IntPtr bminfo, IntPtr pixdat ) { SaveFileDialog sd = new SaveFileDialog(); sd.FileName = picname; sd.Title = "Save bitmap as..."; sd.Filter = "Bitmap file (*.bmp)|*.bmp|TIFF file (*.tif)|*.tif|JPEG file (*.jpg)|*.jpg|PNG file (*.png)|*.png|GIF file (*.gif)|*.gif|All files (*.*)|*.*"; sd.FilterIndex = 1; if( sd.ShowDialog() != DialogResult.OK ) return false; Guid clsid; if( ! GetCodecClsid( sd.FileName, out clsid ) ) { MessageBox.Show( "Unknown picture format for extension " + Path.GetExtension( sd.FileName ), "Image Codec", MessageBoxButtons.OK, MessageBoxIcon.Information ); return false; } IntPtr img = IntPtr.Zero; int st = GdipCreateBitmapFromGdiDib( bminfo, pixdat, ref img ); if( (st != 0) || (img == IntPtr.Zero) ) return false; st = GdipSaveImageToFile( img, sd.FileName, ref clsid, IntPtr.Zero ); GdipDisposeImage( img ); return st == 0; }

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  • How do I get only two form fields to show instead of all 5 on initial page load? CSS

    - by marcamillion
    Here is the implementation: http://jsfiddle.net/AdQfB/2/ If you notice, when you click 'Login' or 'Register' before entering anything, you should see a few fields disappear and re-appear respectively. I would like for this page to display the view of just the two fields on the first load (rather than the current 5 it shows on first load), then when the user clicks the 'register' link, it shows the other 3 - for a total of 5. How do I do that? Thanks

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  • qTip pop ups come in from top left of screen (on first load)

    - by franko75
    Hi, not sure if i'm set things up incorrectly - I don't seem to see anyone else with this problem, but my qTip popups (all ajax loaded content) are loading quite erratically, in that they are often animating in from off screen before appearing in the correct position. Is there a simple solution to this which I may have missed? Thanks again for your help. HTML markup: <span class="formInfo"> <a href="http://localhost/httpdocs/index.php/help/kc_dob" class="jTip" name="" id="dob_help">?</a> </span> qTip initialisation.. //set up for qtip function initQtip() { $('a.jTip').each(function() { $(this).qtip( { content: { // Set the text to an image HTML string with the correct src URL to the loading image you want to use text: '<img src="/media/images/wait.gif" alt="Loading..." />', url: $(this).attr('href') // Use the rel attribute of each element for the url to load }, position: { adjust: { screen: true // Keep the tooltip on-screen at all times } }, show: { when: 'click', solo: true // Only show one tooltip at a time }, hide: 'unfocus', style: { tip: true, // Apply a speech bubble tip to the tooltip at the designated tooltip corner border: { width: 10, radius: 10 }, width: { min: 200, max: 500 }, name: 'light' // Use the default light style } }); //prevent default event on click }).bind('click', function(event){ event.preventDefault(); return false; }); }

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  • Authentication Problem in Silverlight - Cannot connect to SQL Server

    - by Johann
    Hi All, At the moment, when I try to register a user using the default Business Template in Silverlight, I am getting an error. Basically I am following a tutorial found on Channel 9 on how to build a business app with Silverlight. "An error has occurred while establishing a connection to the server. (provider: Named Pipes Provider, error: 40 – Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 5) An error has occurred while establishing a connection to the server. When connecting to SQL Server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. (provider: Named Pipes Provider, error: 40 – Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 1326)". I found a blog where it identifies the problem, and followed every step, however I am still getting the same problems. Here is my connection string:- <add name="SIEventManagerEntities" connectionString="metadata=res://*/EventManagerDBModel.csdl|res://*/EventManagerDBModel.ssdl|res://*/EventManagerDBModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=MONFU-PC;Initial Catalog=SIEventManager;Integrated Security=SSPI;MultipleActiveResultSets=True&quot;" providerName="System.Data.EntityClient" /> Any help would really be very much appreciated! Thanks

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  • Check for Windsor Container Component Instance

    - by jeffn825
    How can I use my Windsor container to check if an instance (not just a component) has been registered? ie. container.ContainsInstance(typeof(MyType)) [EDIT] Another way of writing this might be Kernel.GetAssignableHandlers(typeof(object)) .Where(handler => handler.Service == typeof(MyType) || handler.ComponentModel.Implementation == typeof(MyType)) .Any(handler => handler.***Instance*** != null) Note that the property Instance doesn't exist in the API. Thanks.

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  • How to parse time stamps with Unicode characters in Java or Perl?

    - by ram
    I'm trying to make my code as generic as possible. I'm trying to parse install time of a product installation. I will have two files in the product, one that has time stamp I need to parse and other file tells the language of the installation. This is how I'm parsing the timestamp public class ts { public static void main (String[] args){ String installTime = "2009/11/26 \u4e0b\u5348 04:40:54"; //This timestamp I got from the first file. Those unicode charecters are some Chinese charecters...AM/PM I guess //Locale = new Locale();//don't set the language yet SimpleDateFormat df = (SimpleDateFormat)DateFormat.getDateTimeInstance(DateFormat.DEFAULT,DateFormat.DEFAULT); Date instTime = null; try { instTime = df.parse(installTime); } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.println(instTime.toString()); } } The output I get is Parsing Failed java.text.ParseException: Unparseable date: "2009/11/26 \u4e0b\u5348 04:40:54" at java.text.DateFormat.parse(Unknown Source) at ts.main(ts.java:39) Exception in thread "main" java.lang.NullPointerException at ts.main(ts.java:45) It throws exception and at the end when I print it, it shows some proper date... wrong though. I would really appreciate if you could clarify me on these doubts How to parse timestamps that have unicode characters if this is not the proper way? If parsing is failed, how could instTime able to hold some date, wrong though? I know its some chinese,Korean time stamps so I set the locale to zh and ko as follows.. even then same error comes again Locale = new Locale("ko"); Locale = new Locale("ja"); Locale = new Locale("zh"); How can I do the same thing in Perl? I can't use Date::Manip package; Is there any other way?

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  • Are Objective-C initializers allowed to share the same name?

    - by NattKatt
    I'm running into an odd issue in Objective-C when I have two classes using initializers of the same name, but differently-typed arguments. For example, let's say I create classes A and B: A.h: #import <Cocoa/Cocoa.h> @interface A : NSObject { } - (id)initWithNum:(float)theNum; @end A.m: #import "A.h" @implementation A - (id)initWithNum:(float)theNum { self = [super init]; if (self != nil) { NSLog(@"A: %f", theNum); } return self; } @end B.h: #import <Cocoa/Cocoa.h> @interface B : NSObject { } - (id)initWithNum:(int)theNum; @end B.m: #import "B.h" @implementation B - (id)initWithNum:(int)theNum { self = [super init]; if (self != nil) { NSLog(@"B: %d", theNum); } return self; } @end main.m: #import <Foundation/Foundation.h> #import "A.h" #import "B.h" int main (int argc, const char * argv[]) { NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; A *a = [[A alloc] initWithNum:20.0f]; B *b = [[B alloc] initWithNum:10]; [a release]; [b release]; [pool drain]; return 0; } When I run this, I get the following output: 2010-04-26 20:44:06.820 FnTest[14617:a0f] A: 20.000000 2010-04-26 20:44:06.823 FnTest[14617:a0f] B: 1 If I reverse the order of the imports so it imports B.h first, I get: 2010-04-26 20:45:03.034 FnTest[14635:a0f] A: 0.000000 2010-04-26 20:45:03.038 FnTest[14635:a0f] B: 10 For some reason, it seems like it's using the data type defined in whichever @interface gets included first for both classes. I did some stepping through the debugger and found that the isa pointer for both a and b objects ends up the same. I also found out that if I no longer make the alloc and init calls inline, both initializations seem to work properly, e.g.: A *a = [A alloc]; [a initWithNum:20.0f]; If I use this convention when I create both a and b, I get the right output and the isa pointers seem to be different for each object. Am I doing something wrong? I would have thought multiple classes could have the same initializer names, but perhaps that is not the case.

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  • What is the MSBuild equivalent to ant's -project-help?

    - by Jeremy Stein
    I come from an ant background, and I'm starting to use msbuild. I want to create a .proj file with targets for clean, compile, deploy, etc. In ant, I would expect my user to run ant -project-help to get a list of the targets with their descriptions. There doesn't appear to be anything like this with msbuild, so I was thinking of setting DefaultTargets to "Help" and adding this target: <Target Name="Help"> <Message Text="/t:Clean - Remove all bin folders and generated files"/> <Message Text="/t:Compile - Generate assembly"/> <Message Text="/t:Deploy - Install the assembly"/> </Target> When I run msbuild, I see this: Microsoft (R) Build Engine Version 3.5.30729.1 [Microsoft .NET Framework, Version 2.0.50727.3053] Copyright (C) Microsoft Corporation 2007. All rights reserved. Build started 5/13/2010 9:00:00 AM. Project "C:\MyProject\MyProject.proj" on node 0 (default targets). /t:Clean - Remove all bin folders and generated files /t:Compile - Generate assembly /t:Deploy - Install the assembly Done Building Project "C:\MyProject\MyProject.proj" (default targets). Build succeeded. 0 Warning(s) 0 Error(s) Time Elapsed 00:00:00.05 My target description are hidden among all the other output. It feels like I have a paradigm-mismatch here. What's the best way to provide the build functionality I want so that users know where to find each target?

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  • Programatically created UITableViewCell subclass only working on highlight

    - by squarefrog
    I've created a subclass of UITableViewCell but I'm struggling to get it to work properly. If I use UITableViewStyleDefault then the class only works when highlighted. If I use UITableViewStyleValue1 then it mostly works but I'm unable to change label fonts much. I tried researching but it seems everyone is doing this via a .xib file, but not programatically. Implementation file #import "ASCustomCellWithCount.h" @implementation ASCustomCellWithCount @synthesize primaryLabel,secondaryLabel,contentCountImage,contentCount; - (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier { self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]; if (self) { // Initialization code contentCountImage = [[UIImageView alloc] initWithImage:[UIImage imageNamed: @"tableCount.png"] ]; primaryLabel = [[UILabel alloc] init]; primaryLabel.textAlignment = UITextAlignmentLeft; primaryLabel.textColor = [UIColor blackColor]; primaryLabel.font = [UIFont systemFontOfSize: 20]; primaryLabel.backgroundColor = [UIColor clearColor]; secondaryLabel = [[UILabel alloc] init]; secondaryLabel.textAlignment = UITextAlignmentLeft; secondaryLabel.textColor = [UIColor blackColor]; secondaryLabel.font = [UIFont systemFontOfSize: 8]; secondaryLabel.backgroundColor = [UIColor clearColor]; contentCount = [[UILabel alloc] init]; contentCount.textAlignment = UITextAlignmentCenter; contentCount.font = [UIFont boldSystemFontOfSize: 15]; contentCount.textColor = [UIColor whiteColor]; contentCount.shadowColor = [UIColor blackColor]; contentCount.shadowOffset = CGSizeMake(1, 1); contentCount.backgroundColor = [UIColor clearColor]; [self.contentView addSubview: contentCountImage]; [self.contentView addSubview: primaryLabel]; [self.contentView addSubview: secondaryLabel]; [self.contentView addSubview: contentCount]; } return self; } - (void)layoutSubviews { [super layoutSubviews]; CGRect contentRect = self.contentView.bounds; // CGFloat boundsX = contentRect.origin.x; primaryLabel.frame = CGRectMake(0 ,0, 200, 25); secondaryLabel.frame = CGRectMake(0, 30, 100, 15); contentCount.frame = CGRectMake(contentRect.size.width - 48, contentRect.size.height / 2 - 13, 36, 24); contentCountImage.frame = CGRectMake(contentRect.size.width - 48, contentRect.size.height / 2 - 12, 36, 24); } - (void)setSelected:(BOOL)selected animated:(BOOL)animated { [super setSelected:selected animated:animated]; // Configure the view for the selected state } - (void)dealloc { [primaryLabel release]; [secondaryLabel release]; [contentCountImage release]; [contentCount release]; } @end And then to create the cell I use - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; ASCustomCellWithCount *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[ASCustomCellWithCount alloc] initWithStyle: UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } cell.textLabel.text = [NSString stringWithFormat:@"%@", [tempArray objectAtIndex: indexPath.row]]; cell.contentCount.text = @"49"; return cell; }

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  • How can I stop the browser viewport moving to the top of the page when the user clicks on a jQueryUI radio button?

    - by ben
    I have got some radio buttons setup like this: <div id="typeRadios"> <input id="note_notetype_note1" name="note[notetype]" type="radio" value="note1" /><label for="note_notetype_note1">note1</label> <input id="note_notetype_note2" name="note[notetype]" type="radio" value="note2" /><label for="note_notetype_note2">note2</label> </div> That I turn into jQueryUI buttons like this: $("#typeRadios").buttonset(); This is the resulting HTML: <input type="radio" value="note1" name="note[notetype]" id="note_notetype_note1" class="ui-helper-hidden-accessible"> <label for="note_notetype_note1" aria-pressed="false" class="ui-button ui-widget ui-state-default ui-button-text-only ui-corner-left" role="button" aria-disabled="false"><span class="ui-button-text">note1</span></label> <input type="radio" value="note2" name="note[notetype]" id="note_notetype_note2" class="ui-helper-hidden-accessible"> <label for="note_notetype_note2" aria-pressed="false" class="ui-button ui-widget ui-state-default ui-button-text-only ui-corner-left" role="button" aria-disabled="false"><span class="ui-button-text">note2</span></label> The buttons work, but whenever I click one, the browser view-port gets returned to the top of the page, the same way it happens when you click on a <a href="#">link</a> link. I am using jQuery 1.4.2 and jQueryUI 1.8.7. How can I prevent this behaviour? Thanks for reading. EDIT: The <a href="#">link</a> part was missing.

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  • How to use Hessian in iphone?

    - by Shikhar
    Hello, Is there any one who can help me to understand how we can implement Hessian protocol in iPhone. I have Hessian kit, but its not that straightforward as I thought. Please help me, either by Hello World example or some link which explain Hessian implementation. Thanks Shikhar

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  • Not able to play videos (from youtube) in WebView

    - by user1205193
    I am using a webview to display a video (could be from youtube or vimeo) in my app. In order to not load the video webpages in the default Android Browser, I am also extending the WebViewClient so I can override the shouldOverrideUrlLoading method. This way the video webpage loads successfully in the WebView. However, when I click on the embedded video on the WebView, it does not play. If I do not override the shouldOverrideUrlLoading method, and let the video webpages load in the default Android browser, the videos work just fine. Any ideas why the videos are not working in the WebView? Also, the main reason why I overrode the shouldOverrideUrlLoading method is because if I do not do that, then when I exit the Android browser to come back to my activity (by hitting the back button on the phone), I see a white screen. Upon hitting the back button twice, I am able to get back to my Activity. I am using the emulator to do this test. Here is my code: public class YoutubeLink extends Activity { WebView myWebView; String video_url; private class HelloWebViewClient extends WebViewClient { @Override public boolean shouldOverrideUrlLoading(WebView view, String url) { view.loadUrl(url); return true; } } @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.youtubelink); //Retrieving data from ListSample.java Bundle extras = getIntent().getExtras(); if(extras !=null) { video_url = extras.getString("video_url"); Log.d("inside YoutubeLink.java", video_url); } myWebView = (WebView) findViewById(R.id.web); myWebView.getSettings().setJavaScriptEnabled(true); myWebView.setWebViewClient(new HelloWebViewClient()); myWebView.loadUrl(video_url); } @Override public boolean onKeyDown(int keyCode, KeyEvent event) { if ((keyCode == KeyEvent.KEYCODE_BACK) && myWebView.canGoBack()) { myWebView.goBack(); return true; } return super.onKeyDown(keyCode, event); }}

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  • WinForm-style Invoke() in unmanaged C++

    - by Matt Green
    I've been playing with a DataBus-type design for a hobby project, and I ran into an issue. Back-end components need to notify the UI that something has happened. My implementation of the bus delivers the messages synchronously with respect to the sender. In other words, when you call Send(), the method blocks until all the handlers have called. (This allows callers to use stack memory management for event objects.) However, consider the case where an event handler updates the GUI in response to an event. If the handler is called, and the message sender lives on another thread, then the handler cannot update the GUI due to Win32's GUI elements having thread affinity. More dynamic platforms such as .NET allow you to handle this by calling a special Invoke() method to move the method call (and the arguments) to the UI thread. I'm guessing they use the .NET parking window or the like for these sorts of things. A morbid curiosity was born: can we do this in C++, even if we limit the scope of the problem? Can we make it nicer than existing solutions? I know Qt does something similar with the moveToThread() function. By nicer, I'll mention that I'm specifically trying to avoid code of the following form: if(! this->IsUIThread()) { Invoke(MainWindowPresenter::OnTracksAdded, e); return; } being at the top of every UI method. This dance was common in WinForms when dealing with this issue. I think this sort of concern should be isolated from the domain-specific code and a wrapper object made to deal with it. My implementation consists of: DeferredFunction - functor that stores the target method in a FastDelegate, and deep copies the single event argument. This is the object that is sent across thread boundaries. UIEventHandler - responsible for dispatching a single event from the bus. When the Execute() method is called, it checks the thread ID. If it does not match the UI thread ID (set at construction time), a DeferredFunction is allocated on the heap with the instance, method, and event argument. A pointer to it is sent to the UI thread via PostThreadMessage(). Finally, a hook function for the thread's message pump is used to call the DeferredFunction and de-allocate it. Alternatively, I can use a message loop filter, since my UI framework (WTL) supports them. Ultimately, is this a good idea? The whole message hooking thing makes me leery. The intent is certainly noble, but are there are any pitfalls I should know about? Or is there an easier way to do this?

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  • Add methods to generated WCF client proxy code

    - by dcstraw
    I'd like to add one additional method for each service operation in my WCF client proxy code (i.e. the generated class that derives from ClientBase). I have written a Visual Studio extension that has an IOperationContractGenerationExtension implementation, but this interface only seems to expose the ability to modify the service interface, not the ClientBase-derived class. Is there any way to generate new methods in the proxy client class?

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  • Constructor initializer list: code from the C++ Primer, chapter 16

    - by Alexandros Gezerlis
    Toward the end of Chapter 16 of the "C++ Primer" I encountered the following code (I've removed a bunch of lines): class Sales_item { public: // default constructor: unbound handle Sales_item(): h() { } private: Handle<Item_base> h; // use-counted handle }; My problem is with the Sales_item(): h() { } line. For the sake of completeness, let me also quote the parts of the Handle class template that I think are relevant to my question (I think I don't need to show the Item_base class): template <class T> class Handle { public: // unbound handle Handle(T *p = 0): ptr(p), use(new size_t(1)) { } private: T* ptr; // shared object size_t *use; // count of how many Handles point to *ptr }; I would have expected something like either: a) Sales_item(): h(0) { } which is a convention the authors have used repeatedly in earlier chapters, or b) Handle<Item_base>() if the intention was to invoke the default constructor of the Handle class. Instead, what the book has is Sales_item(): h() { }. My gut reaction is that this is a typo, since h() looks suspiciously similar to a function declaration. On the other hand, I just tried compiling under g++ and running the example code that uses this class and it seems to be working correctly. Any thoughts?

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  • Are there any Parsing Expression Grammar (PEG) libraries for Javascript or PHP?

    - by Peter J. Wasilko
    I find myself drawn to the Parsing Expression Grammar formalism for describing domain specific languages, but so far the implementation code I've found has been written in languages like Java and Haskell that aren't web server friendly in the shared hosting environment that my organization has to live with. Does anyone know of any PEG libraries or PackRat Parser Generators for Javascript or PHP? Of course code generators in any languages that can produce Javascript or PHP source code would do the trick.

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  • +(void) initialize in objecive c class static variables construstor

    - by sugar
    I found some sample code from here. static UIImage *backgroundImageDepressed; /** * */ @implementation DecimalPointButton + (void) initialize { backgroundImageDepressed = [[UIImage imageNamed:@"decimalKeyDownBackground.png"] retain]; } is it something like this - +(void) initialize method initialize static variables of a class ( interface ) in objective c ? I have never seen this before. Please need your guidance on it. Thanks in advance for sharing your great knowledge. Sagar

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