I'm developing a WP7 app with a couple of pages. Everything looks fine in debug mode, but when changing to release mode, two bad things happen:
One page remains completely blank (black in dark theme) without throwing any error. However, in the WYSIWYG XAML editor it looks flawless. Also, the code behind is executed (seen using the debugger).
On another page, an ListBox element is still null after InitializeComponent() has finished. It's inside an initially hidden Popup.
What are the differences between release and debug build that could cause those issues? I have no idea.
Update
The first problem solved itself when I commented everything out and back in, step by step. At the end it worked without any actual changes, so I guess it was a caching problem of Visual Studio or so.
For the second problem, I found a work-around: Setting the container Popup to IsOpen="True" in XAML and closing it at the very end of the page's constructor (after InitializeComponent() has been called). But still I cannot see the reason for it.
Related
I know there are a lot of problems like that and you all might think this is a duplicate but NO... this problem is different.
When I add a custom user control to a project and rebuild it, the control is added to the toolbox. If I try to add another one it does not show up in the toolbox. If I close visual studio and reopen it the first control also was removed from the toolbox and will never appear again. From now on the project is broken and no control added, remove + readded will ever show up in the toolbox. So I create a new project and it starts from the beginning.
Before this tip appears I'll say it: Automatically Populate Toolbox is True. Nothing helps against this problem. Build Project/Solution, Rebuild, Clean+Rebuild, Restart of VS, Restart of Computer, Unload and reload the project, set toolbox back to default. Nothing works.
Any ideas??
You have to remember that the designer call your code constructor and some other methods at design time.
If you build the code and the control does not appears and it has not been hidden by an attribute, then probably the code you wrote is not compatible with the designer. For example, the control might throw an exception in design mode because of incorrect code.
The attribute is [ToolboxItem(false)]. If you have a base class that hide it, it will also be hidden in derived class if not specified otherwise.
You will have the same problem if that control is used in another component. You won't see it if it does not compile and run correctly.
The trick to debug that kind of problem, is to attach a debugger from a second instance of Visual Studio to find where in your code you throw an exception.
If the control does not work at run-time, better to fix that first as if it also fix design problem, it is simpler to debug that way.
Otherwise, you have to ensure that your project dependencies are correct. The toolbox will only shows component from DLLs that are referenced by the current project (or from itself I think).
The best way to explain this is to describe how I can reproduce the problem at will.
Open an existing Windows Form file in the designer
Open the toolbox and click a custom UserControl
Click in the form in the designer to add it
VS2013 hangs (does NOT crash); kill VS2013 and relaunch it
Open the form again
Reset the toolbox and re-add the DLL that contains my custom UserControls
Try adding the control to the form--it works just fine!
Close VS2013
Open VS2013
Repeat the task of adding the custom UserControl to a form
VS2013 hangs
So, the moral of the story is that after closing and reopening VS2013, any attempt to add a custom usercontrol will hang VS2013, and the only way to remedy it is to reset the toolbox and re-add the usercontrol DLL; that remedy only lasts until VS2013 is exited and launched again.
Lots of googling has yielded suggestions regarding using a second VS instance to attach to the first and see the exception that is thrown, but there's no exception being thrown; the application just hangs.
The one thing I found that most-closely described my issue turned out to be related to some remote-desktop software that I'm not using.
Anybody got any ideas? I haven't tried reinstalling Visual Studio, as that represents a fairly significant amount of down-time. Last resort sort of thing (and I've read some things that indicated it won't be helpful).
Edit: Apparently sometimes the reset/re-add doesn't make it better.
Edit: Some additional things I should have mentioned:
There is no devenv.exe when I try to use a second VS instance to
debug, so I end up choosing WDExpress.exe
The particular user control is mature and has not changed recently, and is in use on many forms in the project
The issue only occurs when adding a new instance of the control; the hang does not occur simply by attempting to launch the designer for a form that already contains one.
The latest VS2013 update may have fixed it; it's not happening right now and I don't want to anger the gods by trying to reproduce it again until I get my work done.
Hanging Visual Studio with a custom UserControl is very easy to do. A simple example is all it takes, double-click the design surface and write:
private void UserControl1_Load(object sender, EventArgs e) {
while (true) { }
}
Compile and drop the added control from the top of the toolbox and drop it on a form. Show is over.
You probably did not spend enough time using the guidance you already found or we'd have a stack trace to look at. Attaching a debugger is easy enough and you'd be ahead if the code throws an exception. But it doesn't, a hang like this doesn't throw. Exercise debugging this particular simple hang to find out how to do it:
Start VS again, Debug > Attach to Process > select devenv.exe
Important: click the Select button above the process list. You'll need to select the "Debug these code types" radio button and tick "Managed (v4.5, v4.0)" as well as "Native". Now click Attach.
Give it time to load the symbol files, takes quite a while, especially if that was never done before.
Use Debug > Break All.
If you are lucky then it now stops on the exact statement that causes the hang. Likely in this case. This is however not guaranteed, it might also break on one of the many threads that are running inside devenv.exe, which ever happened to be active at the exact moment the debugger broke in.
In which case you need to use Debug > Windows > Threads to select the thread on which the UserControl code is running. Should be the one labeled "Main Thread". Double-click it.
If the editor doesn't switch to the source code file with the hang then use Debug > Windows > Call Stack to get insight in how the hang occurred. Update the question with that trace if you need more help.
In general, prime candidates for code in your UserControl that can cause the hang are its constructor, its Load event and its Paint event. Use the DesignMode property to bypass dangerous code that is not likely to work well when it runs inside the designer instead of the regular process. And beware of the chicken-and-egg problem, if you have a plain bug in your UserControl then it can easily strike first at design time, before you get a chance to debug it like you normally would. Disabling chunks of code may be necessary to increment towards the bug, use DesignMode to get there.
One more detail, this is tagged [c++-cli]. You must select the old debugging engine to debug C++/CLI code. Tools > Options > Debugging > General > tick the "Use Managed Compatibility Mode" checkbox.
The issue seems to have vanished subsequent to updating VS2013 to 12.0.40629.0 Update 5, found by selecting TOOLS > Extensions and Updates, then selecting Updates on the left.
It may not work in all cases of seemingly-inexplicable UserControl-incited hangs in the Designer, but it seemed to solve the problem for me. I'm putting this here (rather than deleting the question) in case my experience can help someone else.
I've been working on a SL5 app for a few days. I've mostly been using a hard coded dummy data collection when styling my app's view. Everything has been working fine, but now I want to connect it to a dynamic data collection generated by my view model (using the data service technique where you have design time & real data depending on the IsInDesignTool property.
After I cleared out the control of the hard coded data and bound it to a collection in my view model. When I run it in debug mode, I see an unhandled exception being thrown in App.xaml.cs. The exception args don't say exactly what the problem is (it is simply saying "Value does not fall within the expected range" but when I look at the sender I find the following coming from the MainWindow (my app only has a single view): "Out-of-browser specific settings do not affect in-browser applications."
Further, when I try to view the MainWindow in the designer in VS, it doesn't render and instead shows an error (the rendered exception in the designer doesn't have any of my namespaces in it, just things about controls & UIElements).
I'm at a bit of a loss how to troubleshoot this. I didn't set anything for out-of-browser when building the app and since it worked with dummy data collections, why would it suddenly have this issue (seems like if I was using an out-of-browser property it would have shown up before I bound the data to the view).
Tips/pointers?
(sorry for my bad english)
I am not sure on what is happening but I saw the error "Out-of-browser specific..." when I tried to access some specific property only available to OOB while running on browser. The solution was to test if running oob before using the property:
if (Application.Current.IsRunningOutOfBrowser)
{
Application.Current.MainWindow.WindowState = WindowState.Maximized;
}
The other problem possibly is unrelated - and sometimes can be really hard to debug - one thing that helped me is to open another instance of VS and attach it to the one where you are seeing the problem. With this setup, go to your problematic View and change to "design view" - keep an eye on the Output window of the attached VS to see if some meaningful exception is shown.
I had a similar issue.
I did put a Textbox inside kind of Listbox (radPanelBar) and added
HorizontalScrollBarVisibility="Auto" to the Textbox. It seems that the textbox had problems when to show the scrollbar and when not. Adding
ScrollViewer.HorizontalScrollBarVisibility="Disabled" to the Listbox did solve it ( so, no OOB issue at all ).
I'm not entirely sure what the error was, but it wasn't at all realted to OOB. I'm using a data service approach (in design time I programatically build real data, not the Expression Blend sample data, but when not in a design tool, it uses the REST services). I started disabling a lot of things in my dynamic data and slowly added them back. Somewhere along the way my dummy data generation was fouling things up, but SL thought it was an OOB issue.
I'm making an application to dynamically add user controls on a Canvas and drag them around.
First I made a window with a canvas to drag them in and everything worked fine.
Then i made a user control with the code from the window. I added the control to a new window and everything still was working fine.
Now I try to add my control to the main application and the performance is very slow. The controls still follow the mouse but very slow. The application does have several other user controls. Where does this huge performance hit come from and how can I avoid it?
The cpu only uses 50% and when it was working good it went to 100%.
Thank you for you're help
David
EDIT:
I resolved the problem.
By moving the user-controls there was an error in the image url wich prevented the application to run smoothly.
By changing the url's everything went back to normal.
Ive used JoshSmiths DragCanvas for this kind of thing. It work great with no lag.
JoshSmiths DragCanvas # CodeProject
I resolved the problem. By moving the user-controls there was an error in the image url which prevented the application to run smoothly.
By changing the url's everything went back to normal.
Make sure to check you're url's if you're having sudden performance issues.
I'm making a Sketchflow WP7 application which is working fine, except Navigation is sometimes buggy. Sometimes when I go to a screen and try and click it doesn't work, some times it does. I'm using the MouseLeftButtonDown Event to trigger it. After it 'freezes' I can no longer navigate via the map either, though before it freezes I can. I'm not sure if any errors are thrown because I'm not aware of a real time silverlight console. Sketchflow doesn't have a 'Debug Project' option only a 'Run Project' one.
It's very unpredictable, sometimes it works, sometimes it doesn't (though some links are more unreliable than others). Sometimes it gets stuck in different screens. I've tested this across browsers and computers and while sometimes a new browser occasionally has a better success rate, something always gets stuck.
I'm afraid I'm probably leaving out some details so feel free to ask for them. I'm not really very familiar with Silverlight and Sketchflow, I'm just working on a prototype so it seems like I shouldn't have to deal with any code based issues...
Thanks!
You might want to look for a Click Event rather than MouseButtonDown as that could be anything, it doesnt mean MouseButton Down, MouseButton Up, which resembles a click. this is just the same as if you use your finger to touch the screen, this would also trigger the MouseButton Down Eventhandler
so if I was you try and use the Click eventhandler for your navigation.
You can open the same project in VS (including the free express editions) and run it in the debugger from there to see if an exception is being thrown. That might help narrow down the problem.