This is driving me crazy. I'm working on a C# Forms application that is crashing for some reason when calling _documentList.Items.Clear();. For some reason, Visual Studio never catches the crash and it acts as if the application closed without any errors. I'm in the debugger stepping through line by line, and as soon as I hit the _documentList.Items.Clear();, the debugger stops and the form closes. Please help!
Edit: I've found why the app was crashing, but I'm still not sure why the debugger isn't catching it. This should have been much easier to find than it was.
I was trying to update my GUI from a FileSystemWatcher event, so I had to use this.InvokeRequired and this.Invoke(). I'm no longer getting the crash, but I would still like to know why VS isn't catching this in the debugger. My understanding is I should have been getting an exception with the message "Cross-thread operation not valid:"
I think we don't have listbox.Clear() it shopuld be listbox.Items.Clear();
Have you checked if the listbox have items before stepping into the line where you are clearing the items.
Check the items count of listbox.
It appears that this is a known issue and has been fixed when using Tasks in .NET 4.0. See this question (InvokeRequired Exception Handling) for more info.
Related
I have an error in my form editor preventing me from modifying the form.
I know in which control this occurs but no way to find what exactly causes the problem.
I tried setting breakpoints in the InitializeComponents() of the form I try to open but it doesn't stop (I am in debug mode...). I also tried to attach using a second instant of Visual Studio as demonstrated here, but even when setting all debug exception options to "throw", the attached process doesn't stop and indicate anything about call stack nor other useful information...
All I know is that there is a disposed object I'm trying to access, but absolutely no information as to where in code, etc..
What could I possibly do to debug the situation - knowing which control is the cause but absolutely no idea as to which of the 300 lines of code causes the issue...
Has anyone else ever seen this happen? I've had Visual Studio crash over and over again when typing in an object initializer: https://msdn.microsoft.com/en-us/library/bb384062.aspx
I suspect it's some kind of Intellisense bug, since it seems to occur only when the space or period key is pressed. I'm really curious what's triggering the sudden and reproducible crash and if there's any patches or workaround to prevent it from occurring.
The image shows where the cursor is when typing within the first set of brackets. This code appears in a method, which implements an interface member for the class.
This appears to have been caused by the "HideShow Comments" extension. I'm still not sure why it occurs, but disabling the plugin stops the crash from occurring and re-enabling the extension causes the crash to occur again. This must be a problem with Visual Studio itself, since it's the only common denominator in all these extension-related crashes.
I attached a debugger and caught the following error:
An unhandled exception of type 'System.NullReferenceException'
occurred in HideShow.Implementation. Additional information: Object
reference not set to an instance of an object.
I am making a windows phone 8 application and in the designer view in both blend and VS I get "Unable to determine application identity call" error as a dialog box.
From what I read on stack this is propably because of the Isolated Storage is getting run and the designer can't handle it.
I am wondering is there away I can get some line numbers or something where the errors are happening instead of having to manually go through the code?
By the time you see this message box it is already too late, the exception was caught and handled. You have to catch it when the exception is raised. Which is not so easy to do at design time.
One technique that's worth a shot is to use a debugger to debug Visual Studio itself. Start it again and use Tools + Attach to Process. Locate the first devenv.exe in the list of processes and select it. Set the Attach to: setting to "Managed (v4.5, v4.0)" and click OK. Let it trundle to find the PDBs (takes a while). Debug + Exceptions, tick the Thrown checkbox for CLR exceptions.
Switch back to the original instance of VS and do whatever you did before to trigger the error. The 2nd instance will break in when the exception is thrown. Which some luck you'll see your code on the Call Stack window. If the debugger doesn't break then repeat the exercise but attach to XDesProc.exe, the XAML designer. Good luck with it.
Isn't this
Unable to determine application identity of the caller?
or
Getting Unable to determine application identity of the caller Error
are the same topic????
Don't know, just asking...
Sorry for any inconvenience..
Just answered in my basic question.
I'm afraid, i don't know how to get exact string number, just keep in mind that Designer cant have an access to the IsolatedStorage and check all places where you're working with IsolatedStorage. Basically, what you need to do is to add to all constructors a lines
if (ViewModelBase.IsInDesignModeStatic)
return;
If you're working with MVVM Light, or
if (System.ComponentModel.DesignerProperties.IsInDesignTool)
return;
which is pretty the same but without MVVM Light.
Also, i edited my answer there.
The only error I ever get is SIGABRT in main. This is getting incredibly frustrating as I have to guess what line caused the error and why.
This is a far cry from visual studio's informative error messages. It's basically like sending off an entire novel to an editor and the only notes you get back are: "There is a problem somewhere in your book. There may be many or just one and they are either gramatical or to do with spelling."
I just don't know how anyone can work like this. What am I doing wrong? Surely I'm missing something essential.
Write some NSLog() into your code and you'll see it in the console. It's a great help to narrow down a crash.
if you have encountered memory problems (aka – your app crashes for no apparent reason because you attempted to use an object that you deallocated to soon) setting NSZombieEnabled = YES can help you diagnose the problem.
Normally, when your app crashes in this way and you look at the log it tells you nothing (thanks Apple!). However, if you select your executable (under Executables in Xcode), hit the info button (round blue thing at the top), select arguments and put this in the bottom screen NSZombieEnabled = YES the log will give you more information.
Now, if your app crashes the log will have an indication of the object you attempted to access that has already been deallocated. Not forget to turn it off before you deploy it – you don’t want a bunch of nszombies running around your clients phones…
http://howtomakeiphoneapps.com/nszombie-and-xcode-oh-my/27/
I get the infamous "Dialogs must be user-initiated" Security Exception when I try to print some stuff in Silverlight. As you can see, the dialog is as user-initiated as can be:
John Papa couldn't help me much out neither, because I don't have any breakpoint set. Mr MSDN thinks it could also be that I'm just taking too long, but this is a demo application just as simple as can be.
Any ideas? I guess it's a Visual Studio quirk, maybe some extensions interfering, as things seems to work when I launch the application outside of it. I first thought maybe the Code Contracts are interfering with their IL weaving, but they are deactivated for this project.
Update: This is just a simple Silverlight application that runs locally from the file system. When I do "Start debugging", Visual Studio creates a hosting HTML file containing the Silverlight app in the Debug resp. Release folder of the project, launches the Internet Explorer with that HTML file and attaches the debugger to it.
Update 2: I also get the same error when I create a web project to host the Silverlight app and create a virtual directory for it on IIS.
I might also want to add that I don't have problems with printing in other Silverlight projects regardless of their hosting scenarios.
Update 3: I downloaded FireFox and it works, I don't get the error when I debug with it. So it seems to have to do with my IE8. I uploaded the solution:
http://dl.dropbox.com/u/10401470/Code/Demos/PrintingDemo.zip
I wonder if anyone can reproduce?
Anyone got an idea to which team I should file a bug report? Silverlight team? IE team? VS Debugger team?
I'm able to reproduce this. You have handled the Click twice, once in XAML another time in code. See your MainPage.xaml
<Button x:Name="PrintButton"
Content="Gotta print 'em!" Margin="8"
Click="PrintButton_Click" />
Don't feel bad about it. I did it last time through a misplaced Print inside a loop.
I've also experienced this strange behaviour. A standard button click event immediately invoking an OpenFileDialog. It would frequently generate the same error when being debugged but would eventually be coaxed in to working when the button is clicked several times.
However when built as a release (or perhaps simply by running the same Xap without a debugger attached to the browser) the problem would go away.
Try to remove
if(SightPaleceListBox.Items.Count > 0)
I had the same problem and found out that the reason was this following line:
cnvsMain.Children.Remove(PrintPagePlaceHolder);
cnvMain is on the page that the user pushed the Print button on (I was trying to remove it from that page in order to add it to the canvas that I was going to print).
My tip: try to comment rows one by one, until you find what row causes the problem. Than try to work around it.