The app is using my library which works using threads to do some operation; also it uses SIP VOIP library (obviously it is using threads). GUI is bound to interfaces of both libraries.
I noticed a weird behavior of my app. Usually it works just fine but sometimes after some time (3-5 minutes) it suddenly closes.
It is too irregular to debug it or diagnose.
Anyone had that kind of problem? Any idea what could be the reason for that?
I would recommend you add an application level error handler so that you can log any errors that are occuring that you might be missing. It is as simple as
Application.Current.DispatcherUnhandledException += HandleApplicationException;
Here is an MSDN article that describes it:
http://msdn.microsoft.com/en-us/library/system.windows.application.dispatcherunhandledexception.aspx
Related
(see update below)
While running within the VisualStudio 2010 environment, I can easily tell if my Winform application causes an exception. I just have to go to Debug | Exceptions and make sure that both columns of checkboxes are checked. I then run the application and if any exceptions then I get dropped straight into the offending piece of code.
How do I determine exceptions during testing, when I give test build to a tester. I do not want the tester to run within Visual Studio, just as a regular user. I still want to know if there are exceptions and the pertinent details.
Obviosualy, I should be able to control the process, so that when the code gets released normal execution happens.
Yes, I know about and use try/catch blocks, but I am talking about a method similar to Visual Studio exception catcher and reporter, just possibly compiled into the product and used for deployment to beta testers.
Maybe Visual Studio has such a feature, in which case where and how to set up, or possibly a third party component.
[Update:
I added two sub-questions, which you can find at Unhandled Exception next line or exit.
The solution mentioned below sounds great and with a tweak probably works, just not at the moment.
Inside the Visual Studio both 2010 and now 2012 works great. The exception handler gets called, okay after VS breaks at the line and I say to continue. I decided to test outside the VS2012 IDE, good thing for that. The OS traps the bug, shows the standard an "An Unhandled Exception Occurred" dialog giving the details along with a continue and quit buttons. Selecting continue, just continues the application with no trapping into my uber exception handler. Selecting quite, whites-out the application and displays the standard close window dialog. The quit button also does not call my uber handler.
The purpose is so that my exception handler gets called. I do not need an uber exception handler if I am working inside the VS2012 IDE. The purpose of the handler is for end users and beta testers, namely anyone other than myself and who will not have my development station.
So unless I am missing something, the question is still open.
There are code samples in the other question, enough to copy and paste and create a test application in a couple minutes time.
]
Thanks in advance,
Sarah
I don't know of any automagical ways to reports error in Visual Studio but here is what I do.
Hook into the UnhandledException event for the application.
Use a logging framework like nLog or Log4Net to log the exception and other data you get from that event. Or just write to a text file.
Upload that data either from within your application or have the beta-tester send it to you.
Okay, the Google Uberlord took pitty upon me and I found this wonderful article solving the problem. Praise to the almighty Google.
Here is the link:
http://www.switchonthecode.com/tutorials/csharp-tutorial-dealing-with-unhandled-exceptions
Basically, JRadness had the right idea, just slightly in error. He should have used
Application.ThreadException +=
new System.Threading.ThreadExceptionEventHandler(Application_ThreadException);
rather than
AppDomain.CurrentDomain.UnhandledException +=
new UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);
The author on Switch on the Code talked of three methods, the first of which is what JRadness proposed and does not work for Windows forms.
The autor even solved my other question of Continue and Abort. The OS got bypassed.
Yeah!!
I have a WPF app that uses a non-WPF vendor library. My app does not receive any events that the library fires. I've been told that this is because I need a message pump.
In another (very similar) question, the accepted answer suggested using System.Windows.Threading.Dispatcher.Run().
When I add in that call, however, my window won't pop up-- the app is effectively backgrounded and I have to shut it down with Task Manager.
I'm really stumped here, and I'm not even sure how to investigate it. Any help would be greatly appreciated.
You already have one if you use WPF, there's no other way that it can get any Windows notifications. Every WPF app starts life with a call to Application.Run() on the main thread. It is usually well hidden, auto-generated in the bin\debug\app.g.cs source code file. Application.Run() in turn calls Dispatcher.Run()
Your vendor is correct, without a message loop many COM components go catatonic. But since you have one you need to look for the problem elsewhere. Don't use the component on threads.
I've been working on this problem on and off for about a month. I don't expect anybody to be able to give me a definitive answer. I'm just completely out of ideas at this point and could use anything.
The problem is that my app crashes on only some models of phones. I have an HTC surround and it runs fine. It has also been tested on a Samsung Focus and it works there to. It crashes pretty consistently on a HTC mozart. There are other phones it crashes on but I don't know what models they are. I don't have access to an HTC mozart so debugging has been very difficult.
I'm handling the application UnhandledException event and I have try catch around every background thread. The error handling code never runs.
What I know:
Sometimes it freezes and requires a press of the power button. At least once it required the battery taken out. Most of the time it freezes and then crashes.
Most of the time it crashes on the main menu, before everything displays.
It's not 100% consistent. Sometimes it works for a little bit, but never very long.
It's not because it's out of memory. Most of the time it crashes while using less then 8MB.
When all the exception handling didn't work I added debug logging. This slows things way down but at the same time the issue goes away.
These symptoms make it sound like a deadlock to me. Although I have gone over the code and there is no thread ever entering more then 1 lock at a time.
Any ideas on how I should track this down would be appreciated.
Edit: This is a WP7 version of my game. I've just been able to confirm with a volunteer with an HTC mozart that the simplest conversion of the code meant for to run on the web will crash on the phone. That's code has no networking, isolated storage, or sound.
I also should have mentioned that this has passed certification and was in the marketplace for a few days until I took it down because it got bad reviews (because it was unplayable for some people)
If the devices are locking up, then my suspicions would be to look at the areas where you are closest to the driver level/hardware, which (looking at your game) are:
the display
the sound
It could also be just about due to processing/CPU activity - but generally "User level" code shouldn't be able to lock up your phone - that functionality is reserved for kernel software.
The only way of really testing this is to get hold of a device where this "reliably crashes" (e.g. a Mozart) and to go through the process of disabling bits of functionality one by one.
If this is a Silverlight app, then I'd expect Microsoft to want to help - I'd contact them via AppHub and via their local Evangelist team - they'll have the means and the motivation to assist you.
I'm happy to assist on testing on a developer-unlocked HTC Trophy if that helps!
The only thing I can think of that's unique to the Mozart is that it has an 8MP camera and all others have a 5MP camera.
Are you using a CameraCaptureTask and expecting the returned image to be a certain size?
Other than that, what does the app do? what services and device functionality are you using?
Do you have any network access running on a background thread?
I had roughly the same problem when developing my WP7 app. As far as I can tell it isn't as much model bound as it is device bound. In fact I had my app deployed to 15+ Trophy's (my company gave all their employees one of those) and it would repeatedly crash on some of them all having the same firmware. Some of the feedback I got through the reviews seems to indicate that it also happens in the wild.
In my case the crash occurs primarily (only?) when the app is launched. There does seem to be a strong correlation between internet connectivity and crashing in that I can 'recreate' the crash by putting my phone in flight mode, unplugging the network cable from my computer and then deploying the app. In that case too it immediately crashes and no event or break point is ever raised.
My gut feeling tell me it might have something to do with the map control as that does tend to respond funky to poor connectivity when the application is loading (like displaying an error message that the card cant be loaded while simultaneously displaying the map)
Does your app also use the Map Control (in combination with a Pivot control perhaps?)
Some of the devices have issues where you need set things to "content" instead of "embedded resource" in your project.
Although i've more heard about that issue related to app startup time, as on some devices (HD7?) the load of the app was taking enough time that the app was never allowed to start, the OS thought it was taking too long and killed it.
Edit: In addition to the bounty, we're willing to pay $250 to have this bug fixed in the Firefox/Gecko codebase. Here is a simple test project (Visual Studio 2008 C#) that reproduces the problem.
Edit #2 we're willing to pay $600 to have this bug fixed. See above for sample project that reproduces the problem.
We have a Firefox (Gecko) ActiveX control on our C# Windows Form to display HTML.
When this Firefox ActiveX control is on our form, about 2-3% of our key presses don't make it through. Or rather, a different Windows message is sent:
We hold down the TAB key to tab through 3 regular WinForms text boxes. It will behave correctly 97% of the time. Spy++ tells us WM_KEYDOWN message is sent properly:
normal behavior http://judahhimango.com/images/normaltab.jpg
But randomly, maybe 2-3% of the time, the tab key (or other key) isn't processed right. Spy++ tells us WM_CHAR is being sent instead:
odd behavior http://judahhimango.com/images/screwytab.png
When the odd behavior occurs, either the key is not processed at all, or is processed incorrectly (such as inserting a '\t' character into a textbox that doesn't support tab characters.
This only occurs if the Firefox ActiveX control is on our form.
Our question is: does Firefox/Gecko engine install some kind of keyboard hook that might cause these side effects? Or better yet, how do we fix this problem?
The WM_CHAR message is generated by TranslateMessage call, so a good place to start looking would be the TranslateMessage calls in the Gecko source code.
In the first example code you provided the function is imported only by two libraries - mozctl.dll and xul.dll. Since you claim that the same error happens also with GeckoFX we can take mozctl.dll out of the equation. That leaves us with xul.dll, so given the Gecko source code I would suggest to look into widget\src\windows\nsToolkit.cpp. I am not sure if the code is run if the engine is embedded, but if it is then the library starts a whole new message pump in different thread, which is bound to break.
Unfortunately I can't run or compile the code on my machine (Windows 7 x64 w/o the Mozilla ActiveX control installed), so I can't verify any of this with a debugger. Hope it helps someone to track it down further.
The root problem is that when Mozilla is embedded in another application, it incorrectly pumps Windows messages when it dispatches internal events. Mozilla uses an event system to coordinate across threads or to schedule deferred processing on a thread (see nsIThread, nsIEventTarget). If you embed a web page with a lot of active XMLHTTPRequests, for example, Mozilla will use its event dispatching interface to dispatch events back to javascript and it will pump windows messages as a side effect. Once Mozilla events are fully dispatched, it goes back to the main event loop.
When Mozilla pumps windows messages, it doesn't include the extra processing done by the application's event loop - IsDialogMessage(), TranslateMessage(), PreTranslateMessage(), or any other pre-processing are skipped when Mozilla gets into this state. Symptoms therefore include tab key presses getting inserted as a character instead of being used for dialog navigation, keyboard hotkeys being sporadically ignored, or custom message pre-processing being sporadically skipped. For example, the Outlook 2007/2010 "Compose" screen sporadically loses keystrokes because it relies on custom message pre-processing to handle keyboard input.
See https://bugzilla.mozilla.org/show_bug.cgi?id=582790 for a patch that addresses the problem.
I have Snoop Free and PSM Anti-Keylogger.
One of them detected firefox trying to install a Keyboard Hook.
Mozilla/Firefox file xul.dll attempt at installing at keyboard hook.
DENIED.
I noticed that you have implemented all of the interoperability yourself. Can you try this with the GeckoFX project and see if you get the same error? I use this project at work and haven't encountered any issues yet.
I am kind of lost here, and I don't know what to do
I have a problem that I don't know what the source of it.
We have a large wpf application, that is built similar to prism (composite application)
Actually we are using lots of prism library.
I wrote a module to replace an existing module.
And the application now is loading my module, instead of the old module.
I start to notice, with the new module, that sometimes the application freeze for 20-30 seconds without any response, and then it work smoothly after that.
The freeze is not consistent, and there is no pattern or a specific reason that cause it.
I am suspecting that could be my module that is causing that freeze.
But at the same time, many other developers introduced new code to the application.
My question is there a way to trace that freeze?
Is there a way to compare the old module and the new module that I wrote?
I can run the application with my module, and trace the application, and then I can change the config file to load the old module.
Is there a way to compare between the two?
Should I do profiling?
and if profiling will help, then what should I look for?
any other tool could help?
Thanks a lot for any reply
It sounds like you are doing a long running operation on your UI thread. Are you making any database / webservice calls from the main thread? I think one of the easiest things to do is run it in the debugger, and when it freezes, hit the "pause" button. Visual Studio will pause execution at the current location, and you can examine what is taking so long.
If the problem isn't immediately obvious there, I would definitely start profiling the application to track this down.