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).
I've got a project that contains usercontrols. For some reason, the design view for the window which uses the said controls has stopped functioning and insists on "Invalid Markup" - the error given is that some members of the usercontrols are not recognized or not accessible. The project however compiles and executes just fine. Loading it up in VS2010, the editor works fine, no errors whatsoever - the same even in Expression Blend.
So far I have tried the typical clean, rebuild, manually deleting stuff from obj, updating the .xaml and rebuilding, tried starting VS2012 with /resetuserdata and /resetsettings - the problem persists. I even rolled back to a much older revision of my project, back when the designer was working just fine, no dice - same error. I also tried launching VS2012 as a new windows user to avoid any stored appdata that might be lingering, again a no go.
Is there some other sort of cache or something that I could manually delete?
There's also an issue with the ShadowCache (used for rendering designer) getting out of sync with your XAML in VS2012. I just found this out, as I was having a horrible time with the following error with derived user controls:
The local property XXXX can only be applied to types that are derived from YYYYY.
The shadow cache is located in your user profile directory:
app data\Local\Microsoft\VisualStudio\11.0\Designer\ShadowCache
You can delete everything in there and restart VS2012. After that, things worked much better (for at least a while!)
Delete everything in ShadowCache
C:\Users\username\AppData\Local\Microsoft\VisualStudio\11.0\Designer\ShadowCache\
Copy-pasteable paths
Just copy/paste one of these paths into Windows Explorer. %LOCALAPPDATA% is a Windows Environment Variable it will be replaced with the corresponding value when entered into Explorer (also works in Command Prompt)
VS2012
%LOCALAPPDATA%\Microsoft\VisualStudio\11.0\Designer\ShadowCache\
VS2013
%LOCALAPPDATA%\Microsoft\VisualStudio\12.0\Designer\ShadowCache\
VS2015
%LOCALAPPDATA%\Microsoft\VisualStudio\14.0\Designer\ShadowCache\
ASP.NET
If you develop ASP.NET also delete
%LOCALAPPDATA%\Microsoft\WebsiteCache
%LOCALAPPDATA%\Temp\VWDWebCache
I'm not sure this will fix all cases but this is what worked for me (all the time now).
I have VS2012, using the Blend designer in the IDE, building an x64 application, when I would define a new ICommand and add the Command attribute, I would get the designer isn't supported in x64 error (I forget the exact warning). If I switch to x86, I'd get invalid XAML markup errors complaining the the ICommand wasn't recognized or was not accessible, no matter how many times I rebuilt in x64. If I switch to x86, build, then switch back to x64, voila, not problems with the designer.
Now I recall similar issues with VS2008 and Blend version 3 and 4. From what I've read in other posts, using Any CPU might also resolve the issue.
May be you have added user controls which are not supported or you might have added some wrong parent-child relationship in your user controls . Try removing the suspected User Controls and rebuilding the project . It must fix the issue .
Cheers
You need to re:encode your xaml, open bugged files in ide -> save as -> save encoded (choose UTF8)
I've the same problem while using controls with a custom (no param) Constructor.
Check if the Custom/User Control constructor doesn't require any data that the WPF designer doesn't have. A quick wait to check that is surrounding the whole thing with a try catch, cleaning, rebuilding and then check to see if the problem is solver.
If it is not, try commenting everything except the default WPF Init cod, clean, rebuild and test it out.
In Visual Studio 2013 this is a workaround I using for my Windows Phone Project, http://danielhindrikes.se/visual-studio/workaround-for-invalid-markup-problems-when-developing-for-windows-phone/. I guess it is the same designer that is used when you writing XAML for WPF.
Have tried to delete Shadow Cache but itjust work first time I start Visual Studio, above workaround is the only thing that helped me.
A little late, but something else to consider: If your no-parameter constructor is doing some other work, like getting data that doesn't exist because you are in the designer, add this at the start of your constructor:
if (DesignerProperties.GetIsInDesignMode(new System.Windows.DependencyObject())) return;
// Do work.
This is necessary because the designer does execute your no-parameter constructor which may fail in design mode an give you the invalid markup.
And, regardless of what others are saying, this is not a VS or WPF XAML Parser bug. I ran into this issue today using VS 2015, .Net 4.5.2.
I just had the same problem (program compiling and running fine, XAML designer reporting invalid markup), the issue was that I had accidentally changed the assembly name of one of the projects in my solution, I changed it back and my XAML designer sprang back to life, so check the Properties page of each project in your solution, and ensure the Assembly Name is as you expect it to be.
I think there is no problem in your project, but it is problem in VS 2012. Try to install the latest update for VS 2012 (Update 2) and also check this answer.
Regards,
I have the same Problem with VS 2015 and 2017 but only if I compile for x64 only.
Here it helps if I change compile target (Project properties - Build, its called Plattformziel in german) temporarily to x86, compile to project and switch back to x64.
Maybe this is a "solution" for anybody else.
Has anyone else experience incredibly slow performance in the XAML editor in VS 2010? If I have a new project with a limited number of files, the performance is fine. However, if I have a project with a larger number of XAML files, the XAML editor hangs intermittently every few seconds, making it almost impossible to use.
I should also note that the performance is only slow in one particular project where I am referencing DevExpress 2010. I am not certain if this is related.
Any suggestions on solutions to this problem would be greatly appreciated.
Chris
In Visual Studio 2012:
Go to
Tools > Options > TextEditor > XAML > Misc
Check Always open documents in XAML view and uncheck Automatically populate toolbox items.
In Visual Studio 2015, 2017:
Go to
Tools > Options > XAML Designer
uncheck Automatically populate toolbox items.
This fixed my same problem.
If you don't need the visual designer, you can select a different editor in visual studio:
Right click the xaml file -> Open With... -> Source Code (Text) Editor
You will only lose the split view, intellisense etc. should still work.
If you need to check something in the designer you can still click 'view designer' to open the normal XAML editor again.
If you want to improve the performance of the visual designer, try checking DesignerProperties.GetIsInDesignMode in your code-behind. The visualiser instantiates your controls to know how to display them, thus executing parts of the code-behind.
Like the OP, I had extreme lag in the xaml editor on a project that relied heavily on DevExpress WPF controls. After trying unsuccessfully to resolve this issue with the other solutions posted here, I eventually tried deleting my Solution User Options (.suo) file, which is usually located in the same folder as the solution (.sln) file. This immediately resolved the issue. You may want to read this post about what visual studio stores in the suo file so you can reset anything important (such as build configuration - mine always defaults the active solution platform back to "Mixed Platforms" for example)
Short answer: if you do not use designer much, just replace the default editor for XAML, thus getting rid of XAML visual designer and speeding things up. Right click any XAML file, click Open with... and choose another default editor. Source code (text) editor works just fine.
Now it should be already fine. If you want to understand the details and completely get rid of the slow designer, read the long answer.
Long answer: Here is a nice explanation of what happens and why is it that slow.
A brief todo based on the aforementioned article in order to completely disable the visual designer of XAML:
Under Tools->Options->Text Editor->XAML->Miscellaneous->Default View check Always open documents in full XAML view
Open Task manager and end XAML Designer process XDesProc.exe (Note: for VS2013 right click this process and go to containing folder. Rename the exe to sth else, than end the process)
Standard XAML editor will load this process again (I guess it will not succeed with VS2013 and actions done in P.2). However, right click any XAML file, Open with... and choose another default editor. Source code (text) editor works just fine.
While using dev express, I've noticed some laggy response in the Visual Studio designer. This appears to be due to the license authentication of the DevExpress products.
If you delete the "Licenses.Licx" file (found in the project properties folder) you'll notice a marked improvement in performance.
Note: Removing the license file doesn't stop you from using DevExpress controls. But it does stop VS from constantly authenticating it.
I am using using VS2010 and if I have a form open in designer mode and run my application the designer tab will no longer show the form designer but instead an error will be displayed (and it is only fixed by restarting the IDE) saying:
"To prevent possible data loss before loading the designer, the
following errors must be resolved:"
1 Error:
"The designer could not be shown for this file because none of the
classes within it can be designed. The designer inspected the
following classes in the file: ##### --- The base class ##### could
not be loaded. Ensure the assembly has been referenced and that all
projects have been built"
I then shows the following call stack:
at System.ComponentModel.Design.Serialization.CodeDomDesignerLoader.EnsureDocument(IDesignerSerializationManager manager)
at System.ComponentModel.Design.Serialization.CodeDomDesignerLoader.PerformLoad(IDesignerSerializationManager manager)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.VSCodeDomDesignerLoader.PerformLoad(IDesignerSerializationManager serializationManager)
at System.ComponentModel.Design.Serialization.BasicDesignerLoader.BeginLoad(IDesignerLoaderHost host)
Any help is greatly appreciated this is really annoying.
Thanks,
Joel.
I get this visual studio bug too now and then, and I deeply ignore the error text, instead I do the following:
Close the Design-tab
Reopens the Design mode by double click in Solution Explorer, or by right clicking Source code tab and select View Designer
Suddenly everything works again!
If not helping, you may have to change bullet 2 into:
Close and restart Visual Studio.
Maybe this can help you out.
I usually close the visual form, rebuild the solution, right-click then select "view designer" in the form code.
Very, very annoying. I am thinking of dropping back to VS2008.
Close the form. Clean the solution. Rebuild the solution. Reopen the form. Worked for me when nothing else would.
I had this same issue and I was able to resolve this by creating new project and then compiled and run the project and then I imported all the files and ran the project again and automatically it was working again did nothing extra.
I'm able to avoid restarting VS by doing the following
Add a new user control
Drag and drop some of your custom user controls on to it (If it gives you an error, build the solution again).
Reopen your control.
In my case, I have a winforms project with several custom controls that are used by other custom controls. Whenever I open some of those custom controls, I get a the "The base class ..." error. Adding a new custom control, building the project and then adding some custom controls from my project to the new custom control allowed me to open the custom controls that were giving me the "The base class ..." error.
UPDATE: I think I found the problem. My controls were not 'added' properly to the csproj file. In the csproj file, the files for partial classes of UI controls/components need the 'DependentUpon' attribute.
E.x.:
before:
<Compile Include="Windows\Forms\DataGridView.cs">
<SubType>Component</SubType>
</Compile>
<Compile Include="Windows\Forms\DataGridView.Designer.cs" />
after:
<Compile Include="Windows\Forms\DataGridView.cs">
<SubType>Component</SubType>
</Compile>
<Compile Include="Windows\Forms\DataGridView.Designer.cs">
<DependentUpon>DataGridView.cs</DependentUpon>
</Compile>
I had a situation where a custom user control appeared to be creating the error (not sure why) so I removed references to the user control from the form and the error went away.
It seems that after installing SP1 the problem has gone away.
Thanks for your help everyone.
I had the same problem using A control With Generics
MvpUserControl<Presenter,IViewMode> : UserControl
what I do it's Remove the Reference and Add again, Clean and Rebuild the Solution I Hope this can be useful for anybody else
I had the same problem with VS2010 SP1. Finally using Windows Update I saw some updates for Visual Studio and .Net, I installed them and is not happening any more.
Old post, but for those whom may find this...
Just ran in to this error and for me it was relatively simple fix.
Found that it may have something to do with the names of your classes, and renaming the problematic class to a higher order. That is the alphabetical order it appears in the assembly (Where A is higher than Z).
MSDN Article
Good luck.
This error occur if the Form class is not a first class in the file, for example if there is some helper class at the beginning of the file.
To solve this issue, move all other classes except Form class to the bottom of the file.
Don't code in Form1.Designer.cs. Move your logic to Form1.cs (hit F7 on Form1.cs [Design] tab).
"In the project file (.vcxproj), locate the entry for the target
Framework version. For example, if your project is designed to use the
.NET Framework 4.5, locate
v4.5 in the
element of the element. "
(Microsoft)
In my case the "v4.5" didn't exist so I add it, and everything is good now.
I tried clean solution and re-build solution and worked for me.
Hope this help!
This solution works fine, please follow these steps below to solve your problem:
Check the reference if load correctly
Clean the solution and rebuild again
Clean the project and rebuild again
Clean your project and open it again
I was login as administrator in visual studio . I just close my visual studio and again open it without run as administrator and my problem is solved
I ran into this today after upgrading VS2019. I went to properties, configuration tab, and set the projects to Configuration = Debug, Platform = Any CPU. Then it worked.
I faced this issue.
To prevent possible data loss before loading the designer, the following errors must be resolved:
I found solution for this problem:
Close all open tabs, and refresh (sync active documents) the solution.
For more information, you can see this video : https://youtu.be/Q3x2HBd7BDs
Is there any way to force the WPF designer to reload or refresh, without rebuilding the entire project or solution?
If there's an error, I get an option in the designer view to refresh the designer. But if I don't have an error, how can I get the designer to refresh after I've made a change?
I'm a little late but this is the best solution1 I've found so far: whenever the designer does stupid stuff, I just kill it's process.
Press Ctrl+Shift+Esc
Navigate to the Processes tab.
Kill XDesProc.exe
This also fixes issues for the properties window (like when it gets jammed and you can't type stuff into it).
1 This is a solution for designer issues. Your issues may also be caused by compilation problems, in which case just right click on the solution in the solution explorer, and clean it. The reason behind it is that sometimes the compilation loses synchronicity with the generated files from XAML, and cleaning the solution just deletes those intermediate files; it's like a reset so your compilation can start off with a clean slate.
To do it fast:
Comfortably it's usually the last one if sorted alphabetically.
When it is, it's almost like a ritual for me to quickly pop up the task manager, click any process, press End, Delete, Enter (done), Esc (exit task manager). Instead of restarting VS and waiting for all the loads & unloads, you can do that in 1-2 seconds.
In newer versions of Visual Studio there is an icon on the bottom of the designer to "Disable Project code". If you toggle this off and on it will reload the designer.
You can add this to the Tools menu in Visual Studio.
Once configured, use Tools..XAML Designer Restart:
Alt+T then L
I tried configuring it for Alt+T then X but this clashed with Tools..Choose ToolboX Items.
Update
These days, I prefer to just hit Ctrl+Shift+Esc to bring up the process manager, then X to skip to XDesProc.exe then Delete to kill the rogue process(es).
The Visual Studio designer attempts to keep the rendered view in sync with the XAML. That's the advertised behavior.
The first thing you should check is that there are no errors in the errors window. It may be something as simple as a missing angle bracket.
The second thing to check is whether you have any code (other than your code-behind) which needs to be compiled for the designer to render your XAML correctly. This includes any of your own datatypes that you instantiate in XAML, any custom controls you have written (e.g. MyTextBlock derived from TextBlock), or any classes directly or indirectly in support of design-time data. If so, you need to rebuild your project.
The last thing to check for is possible bugs in the designer. In spite of the advertised behavior, the designer may get out-of-sync due to bugs. In that close, close the XAML window and re-open it. Other tricks that might work are selecting the XAML tab and then the Design tab, or maximizing the XAML pane.
As far as rebuilding your application goes, you don't need to do this as a habit. You only need to recompile it when the above conditions apply. Once they don't apply, you can just edit the XAML. Another way to say this is that if you haven't modified code, you shouldn't need to rebuild (modulo bugs).
I'm not sure, but I think a build will refresh your view in that situation.
There is any event handled in that XAML file, then mostly it will not display the design preview from Visual Studio. If you want to see the design from Visual Studio, try with Command Binding instead of event, you will see the preview.
I'm not sure how this works in WPF editing, but with ASP.NET pages when the design view wont update i can do 2 things
Exit Visual Studio and restart
Go into source view (not split), type something and remove it (not by undoing, just delete or backspare) and save it. Then return to design view, usually the view has been updated then.
When you add a new row of code or a new object, XAML designer is sync but I encountered non-sync behavior when a property of an object is changed.
A tricky way is that when you change a property you only need to remove a ">" character from end of an instruction then retype it.
On the toolbar in the XAML designer, choose the "Disable project code" button to reload the designer link which stays on the right side of "Turn on snapping to snaplines".
Disable project code in the designer
If it is disabled, you can try to check the configuration manager and change processors to "Any CPU".
For projects that target ARM or X64 processors, Visual Studio cannot run project code in the designer, so the Disable project code button is disabled in the designer. Check this:
Debug or disable project code in XAML Designer
For information, I had the same issue with the XAML Designer of Visual Studio Community 2017, i.e. sometimes the designer doesn't show anything, the easiest solution is then to close the XAML file and reopen it.
I also frequently get the exception "An Unhandled Exception has occurred - Click here to reload the designer - Details: The XAML Designer has exited unexpectedly" (the click restarts the designer successfully).
Note that, in this VS version, the process of the XAML designer is not named XDesProc.exe, but UwpSurface.exe. If you prefer or have to kill the process, then the designer shows the same exception as above, and you may restart it.
use process hacker and kill the WpfSurface process (blend only)
Update for designer refresh/reload Visual Studio 2022 Xamarin, taskkill /IM java.exe