Cefsharp: WPF WindowsFormsHost Touch Screen not working

[Jovan-Cheng]

• What version of the product are you using?
  
  
  
  • 1、Nuget 53
  
  
  • 2、build from a branch 49.0.2623
  
  
• What architecture x86 or x64?
  
  
  
  • x64
  
  
• On what operating system?
  
  
  
  • Win7
  
  
• Are you using WinForms, WPF or OffScreen?
  
  
  
  • WPF
  
  
• What steps will reproduce the problem?
  
  
  
  • Reference ：CefSharp.dll CefSharp.Core.dll CefSharp.Winform.dll
  
  
  • Use 'WindowsFormsHost' control in my wpf program
  
  
  • Create 'ChromiumWebBrowser' and add it to 'WindowsFormsHost'
  
  
  • After running, you can display the page, but no Touch effect
  
  
• What is the expected output? What do you see instead?
  
  
  
  • Can touch scroll and pinch
  
  

[amaitland]

@ccnucheng Does the Touch Screen work when using the native WinForms implementation? You can test it using https://github.com/cefsharp/CefSharp.MinimalExample

[Jovan-Cheng]

@amaitland
_- Touch Screen is work when using the native WinForms implementation._
_- Touch Screen is work when using WindowsFormsHost in WPF with Win10_

[amaitland]

Two things to try

• Firstly make sure your app has the relevant compatibility entries in the app.manifest. https://github.com/cefsharp/CefSharp.MinimalExample/blob/master/CefSharp.MinimalExample.Wpf/app.manifest#L37
• Secondly you can attempt to run the message loop on your UI thread, this often fixes a lot of random problems see https://github.com/cefsharp/CefSharp.MinimalExample/commit/15c4a7a7845452c190f6e44c5b7db41ccb504601

The fact it works in Win 10 likely means there isn't a whole lot that can be done. CefSharp is just a wrapper around CEF after all.

[Jovan-Cheng]

@amaitland

• Still can not Touch, when after the App.manifest file modified,
  The CefSettings parameter is already the same as in the example

[amaitland]

The CefSettings parameter is already the same as in the example

I find that unlikely, the browser doesn't function without some sort of message loop processing. Check again.

[Jovan-Cheng]

@amaitland

I find that unlikely, the browser doesn't function without some sort of message loop processing. Check again.

Although still can not touch, but still thank you very mach!

[amaitland]

So you've got the message loop running on the dispatcher? Have you tested on different hardware with Windows 7?

[Jovan-Cheng]

Yes,I addCef.DoMessageLoopWork() in window‘s Loaded event,and use DispatcherTimer execute it,and test on defferent machine with windows 7!It's still can't touch

[amaitland]

You can try CefGlue or ChromiumFx, see if you have better luck with a different framework.

[szymonmalok]

Adding "touch-events=enabled" to command line arguments, when starting CEF, fixed simillar issue I had.

[Jovan-Cheng]

@szymonmalok
Yes,I have added the parameters ,but still can not touch the scrren!

[softwaretirol]

We have the same problem. Hosting the WPF Control in a WindowsFormsHost but Touch Events dont work on Windows 7. On Windows 8 or 10 , there is no problem.

[Jovan-Cheng]

@softwaretirol Did you solve it?

[softwaretirol]

No - we still have the problem.

[toprezr]

Touching Event is initiated, but does not work as expected, If you happen to click on it so 50 times, sometimes an Event is working, but It's random.

[Jovan-Cheng]

Has anyone solved this problem?

[Jovan-Cheng]

OK! I solved it.

[mortalV]

How did you solved it?

[Jovan-Cheng]

@mortalV
@softwaretirol

• Using the open source WmTouchDevice
  
  
  
  • https://github.com/jaytwo/WmTouchDevice
  
  
• Call MessageTouchDevice.RegisterTouchWindow(IntPtr hWnd) in your Window's Loaded event
  
  
  
  • System.IntPtr hWnd = newSystem.Windows.Interop.WindowInteropHelper(this).Handle;
  
  
  • WmTouchDevice.MessageTouchDevice.RegisterTouchWindow(hWnd);
  
  

• Add the CustomControl(WPF) in your project,and inherited from WindowsformsHost
  ```c#
  public class CefWindowsFormsHost : WindowsFormsHost
  {
  static CefWindowsFormsHost()
  {
  DefaultStyleKeyProperty.OverrideMetadata(typeof(CefWindowsFormsHost), new FrameworkPropertyMetadata(typeof(CefWindowsFormsHost)));
  }

  protected override IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
  {
  WmTouchDevice.MessageTouchDevice.WndProc(System.Windows.Window.GetWindow(this), msg, wParam, lParam, ref handled);
  return base.WndProc(hwnd, msg, wParam, lParam, ref handled);
  }
  }
  ```

• Use this Custom WFH(CefWindowsFormsHost) replace the System.Windows.Forms.Integration.WindowsFormsHost

[amaitland]

Great, sounds like there is a valid workaround 👍 Closing

[talbotmcinnis]

@ccnucheng You are a god amongst men. Great job discovering the fix, and amazing community dedication for sharing it in such detail.

[lindexi]

Maybe you can use the WPF control. It fix in https://github.com/cefsharp/CefSharp/pull/2745