`ShowMessageBox` freeze primary window when show a message box on secondary windows

[VShawn]

Description

When call IoC.Get<IWindowManager>().ShowDialog or IoC.Get<IWindowManager>().ShowMessageBox on secondary window, the primary window will be freezen.

With ShowDialog provide by the runtime, primary window works fine.

To Reproduce Code to reproduce the bug, which someone else can run.

Version Info

• Stylet version: 1.3.6
• Runtime version: .Net6

Additional Info

With stylet messagebox:

With system messagebox:

Here is the code related:

https://github.com/1Remote/PRemoteM/blob/dev_net6/Ui/View/Host/TabWindowViewModel.cs#L236-L237

https://github.com/1Remote/PRemoteM/blob/58805bd0bb59757e9016a89cdfd14300a64278b7/Ui/Utils/MessageBoxHelper.cs#L26-L33

And you can get the exe file from: https://github.com/1Remote/PRemoteM/releases

[VShawn]

    var window = new InputWindow
    {
        Title = "title",
        Prompt = "Hi, test native owner window",
        Response = "",
        Result = Results.Cancel,
        ShowInTaskbar = false,
    };
    window.Owner = this;
    window.WindowStartupLocation = WindowStartupLocation.CenterOwner;
    window.ShowDialog();

this above will open a modal dialog to freeze both two window.

So using the native func ShowDialog to show a windows will freeze all of the windows.

Then I noted WindowManager.ShowMessageBox based on native ShowDialog.

That's the reason why WindowManager.ShowMessageBox freeze my two windows.

@canton7 can we make WindowManager.ShowMessageBox a same behaviour like native MessageBox.Show ?

[VShawn]

I have find a workaround for this ticket. I will make a PR for this latter.

  var mbvm = new MessageBoxViewModel();
  mbvm.Setup("Hi, test stylet message box");
  if (IoC.Get<IViewManager>().CreateAndBindViewForModelIfNecessary(mbvm) is Window window)
  {
      window.Owner = this;
      window.Loaded += (o, args) =>
      {
          var dlgWindow = o as Window;
          // dlg don't have a Owner
          if(dlgWindow?.Owner == null)
              return;
          var windows = Application.Current.Windows;
          // enable the window != Owner
          foreach (Window w in windows)
          {
              if (w == dlgWindow.Owner) continue;
              if (w is { IsLoaded: true })
              {
                  if (HwndSource.FromVisual(w) is HwndSource hwndSource)
                      EnableWindow(hwndSource.Handle, true);
              }
          }
      };
      window.WindowStartupLocation = WindowStartupLocation.CenterOwner;
      window.ShowDialog();
  }