When I try to launch a particular background task using Visual Studio, I currently receive the following error:
I tried pressing the Help button, which took me to How to trigger suspend, resume, and background events in Windows Store apps. The page said to look at a certain section in Event Viewer that didn't contain any entries.
The corresponding Windows Store application is both requesting background task permission and registering the task. The application is enabled for the lock screen. The application's project is referencing the background task project, and its manifest is specifying the correct fully-qualified class name of the background task. The correct type of background task has been specified in the manifest.
I was able to resolve this by changing the task registration/location code to call RequestAccessAsync before registering the background task. (Previously, it had registered the background task before asking for access.)
For some reason, this caused the application to request access again. After running the application and granting it permission, I reverted the code back to the previous state.
Now it works correctly again even though the code is the same as it was originally.
For me, I had a problem where I had updated TaskEntryPoint in my manifest but forgot to update it in my code... Frustrating to have to maintain it both places!
It got out of sync via the process of refactoring some classes into a new library, so don't forget to update after the fact if you do that!
You may be able to use reflection to help with this e.g. typeof(LocationTask).FullName
Restarting Visual Studio (2015) solved this problem for me.
You probably already did this, but sometimes one forgets about the easy things.
Related
I am attempting to use a custom control for a live tile in my background agent. I have my live tiles successfully generating with user controls, but I now want to reference a custom control in my user control Xaml. At design time everything looks correct, no errors and I see the custom control presented in the designer, but when I run the app and the background agent runs, I receive this error:
Unknown parser error: Scanner 2147500037
The position noted in the error is the location in the Xaml where I have my custom control. If I remove the custom control the error goes away.
The custom control I am attempting to use (and its source code) can be found here:
http://blogs.u2u.net/diederik/post/2013/11/05/A-Modern-UI-radial-gauge-control-for-Windows-Phone-8-apps.aspx
I do not believe there are any references in this custom control to anything that cannot run in a background agent, so I am wondering if there is some limitation in general to using custom controls in background agents for windows phone?
If anyone has any ideas as to the cause of this error, please let me know.
I was not able to get the control to work but refactored the code to implement the straight Xaml rather than using the control. The end result is the same as what the control offered, but more complicated.
I'm developing a Metro-style app (for Windows 8) using C# and XAML. I have set up my viewmodels to be used as design-time datacontexts, like so:
xmlns:vm="using:hub.ViewModels"
d:DataContext="{d:DesignInstance IsDesignTimeCreatable=True, Type=vm:ViewModels
My app appears to work perfectly when run, but in the design views of both VS 2012 and Blend, I occasionally get this (unhelpful) error message:
An Exception was thrown. TargetException: Error in the application.
Stacktrace
at System.ComponentModel.PropertyChangedEventHandler.Invoke(Object sender, PropertyChangedEventArgs e)
InnerException: None
This only happens in the design view - meaning I can't set breakpoints around all my INotifyPropertyChanged() events.
What is the best approach to debugging design-time errors?
If this happens consistently or semi-consistently, you can attach the debugger to the XAML designer:
Start Visual Studio; open your project and open a XAML file, causing the XAML designer to load
Start a second instance of Visual Studio. Open your project but make sure no XAML documents are open.
Ensure that Just My Code is disabled: From the Tools menu, select Options. Select the Debugging category. In the General page, ensure the check box next to Enable Just My Code is unchecked.
From the Debug menu, select Exceptions... and check the Thrown check box next to Common Language Runtime Exceptions. This will enable first chance handling of all CLR exceptions. If you know the specific type of the exception, you can enable first chance handling for just that type.
From the Debug menu, select Attach to Process. In the Attach to: field, click Select... and check the Managed (v4.5, v4.0) entry in the list and click OK.
This is necessary because the debugger may misdetect the process as a native process if it attaches while the process is executing native code. If your project contains native code, you'll want to check the Native check box in the list as well (you can debug both managed and native code at the same time).
In the Available Processes list box, find the xdesproc.exe that corresponds to your project and click Attach.
If there are multiple processes (usually because you have multiple projects open or because the designer is reloading or has recently reloaded), it can be difficult to determine which designer process belongs to which Visual Studio instance. It's often easiest just to attach to all of them. A tool like Process Explorer can help you figure out which designer process belongs to which instance of Visual Studio.
Note: Do not attach the debugger to a designer process (xdesproc) that belongs to the same instance of Visual Studio that you are using for debugging: doing so is likely to cause Visual Studio to hang. You must always use two different instances of Visual Studio.
Do whatever you need to do to repro the bug. When it occurs, the debugger will break at the point where the exception is thrown. The debugger should load the symbols for your assemblies.
I got here while looking for info on how to debug designer time instance problems, though I did not have the same problem as rikkit. But...I'm sharing the solution to a related issue just in case others having the same problem reach here as well:
Make sure you have the "Enable/Disable Project Code" toggle set to "enabled"...in VS/Blend 2015 it's a small icon below the XAML editor
as shown here.
If it's disabled, this could be the reason your design time instance doesn't seem to be working.
Further, if it's disabled and you attempt to debug using a second VS instance, then when you attach to the XDesProc any breakpoints you set in the code-behind will report that they "will not currently be hit. [because] No symbols have been loaded for this document".
You might think that you need to somehow load the symbols, but if you open up the Modules window attempting to do so, you won't even see your module in the listing.
I lost a couple hours on this issue because of this setting being disabled. Hope this helps others not do the same.
I'm not sure about it but I believe you can check for the IsInDesignModeProperty Field. I remeber having to do so on WinForms sometimes.
Also take a look at this link Troubleshooting WPF Designer Load Failures
I have some code in Form Load event. It is doing fine. But when it reaches to pick data from database, no commands are executing after that. There is no error at all but it just goes silent.
I tested it as follows:
MsgBox("1")
vrStudentName = DsGetPprStatusfromEnrSummary.tblPaperEnrSummary.Rows(0).Item("StudentName")
MsgBox("2")
Please advise.
Thanks
Furqan
Message Box one is showing data but not the message box two. In fact, the second message box statement is not showing any response at all.
This is a nasty problem on 64-bit operating systems. Any exception raised in code that's run from a form's Load event is swallowed without a diagnostic. This is an old problem that is not getting solved because the DevDiv and the Windows groups at Microsoft are pointing fingers at each other. My finger is pointing at the Windows group but that doesn't help either.
Two basic ways to solve this problem:
Project + Properties, Compile tab, scroll down, Advanced Compile Options, change the Target CPU option from x86 to AnyCPU. This disables the Wow64 emulation layer that swallows the exception.
Debug + Exceptions, tick the Thrown box for "Common Language Runtime Exceptions". The debugger stops as soon as the exception is thrown.
Also keep in mind that it is very rarely necessary to use the OnLoad method or Load event. Only code that requires the Size or Location or Handle of the form to be accurate needs it. Anything else belongs in the constructor of the form. That Load is used so often is a VB6 anachronism, carried over in the designer design which made the Load event the default event for a Form. Add a constructor by typing "Sub New".
Well, it seems pretty obvious that the call to DsGetPprStatusfromEnrSummary.tblPaperEnrSummary is never returning; which means the problem is IN THERE somewhere.
So what on eath is it? I'm guessing it's a DataSet, yes?
But you've referenced it staticly, which is YuckyPooPoo(TM) IMHO, because it's a complex artifact, and you've rendered EVERYTHING which references it unisolatable, and therefore fundamentally untestable!
Received answer on Codeproject
In the dialog that comes up, put a tick in every checkbox under both "Thrown" and "Unhandled". Press OK.
Now, when you run your app though the debugger, it will break for any exception, even if you have an active handler. This should help you track down the problem.
Issue RESOLVED
I'm developing a website with ASP MVC 3 and Razor in VS2010 SP1.
When I'm running the site from VS, if the view was open in the IDE, I can edit a view in runtime, and press F5 to show the changes, but if I open the view after run the site, then the view is locked (no message, simply I can write in the VS Editor)
When I stop debuggin the solution, the views that are locked remains locked, and I have to close the file and open id again in order to modify the code.
This behaviour is uncomfortable. Can anyone tell me why sometimes I can write in the VS2010 editor and other times I can't?
Other Notes:
The TFS is not the problem.
It happens in all the VS 2012 SP1 of my office.
It only happens in vb.net projects, not in C# proyects.
It didn't happens in VS2012.
I've disabled all the extensions.
Thanks.
I have experienced this as well.
I've found that just reopening the file, while in debug, works most of the time. The nearest thing I can figure is that you're not actually editing the file but actually viewing a debug version of the file.
This normally happens, for instance, a javascript method causes an exception within the source of that page. It then loads the active version of that page instead of the one you're editing. Though I've had it happen without any errors generated so I'm fairly certain that's not the whole issue. It might be worth posting an issue on http://aspnet.codeplex.com/workitem/list/basic It hasn't happened often enough for me to narrow it down but it sounds like it happens for you more often.
After more than a year suffering this problem, a solution was found.
This MS HotFix for VS2010SP1 solved the issue.
http://connect.microsoft.com/VisualStudio/Downloads/DownloadDetails.aspx?DownloadID=40811
I'm buisy on a DirectX10 game engine and i'm having a problem which has nothing to do with DirectX :P The problem is that in the DLL which contains the engine sometimes a DialogBox is called, just like you would do in normal win32. With the only difference that instead of the HINSTANCE i use the HMODULE which i get when loading the DLL.
Everything seems to be working fine, if i step through my code with F10 (Visual C++ 2008) i can even see it going through my DlgMessageProc function and do everything it should do. The only weird thing is that no dialog is shown and that all of a sudden it jumps out of the message loop and just continues with the rest of the code???
Weirly engough I have the same problem when calling MessageBox from inside my DLL, I get no errors, everything seems to be working fine but no window is shown, nor is the code halted (as normal with messageboxes)
The funny thing is that I have some code from a book which uses the same basic architecture as me and if i compile that everything shows just fine??
So my question, is there any hidden option, pragama comment or other thing i should look at if i want to be able to show MessageBoxes and Dialogs from my Dll?
No as i thought, chaning the manifest doesn't help at all. I also created a separate project where i just test the dialog and its proc function and there everything works perfect (links to a .exe instead of dll)
In the visual studio resource editor's property page for the dialog resource there should be an option in which you can specify - "No Fail Create: True".
Usually dialogs fail to create because a common control cannot be created - usually because InitCommonControlsEx has not been called. Setting the No Fail Create flag lets you see dialog and determine which controls are missing.
Other things to check:
Is there a message in the debug window about a first chance exception? Perhaps its 'jumping out' because of an exception that is being caught and silently handled by Win32. Turn on debugging of first chance win32 exceptions in the Dev Studio exceptions dialog to track that down.
Even this wouldn't explain how a MessageBox call would fail to create a message box.
The only times Ive seen MessageBox fail to work were when:
Resource leaks had made the process run out of available user32 handles - have you checked your apps handle counts using task manager?
the system was in the process of being shut down. Have you called PostQuitMessage and then tried to create a dialog/MessageBox?