Wpf: Modal dialog on top of non-modal window sends main window to back

[lisberPontes]

• .NET Core Version: .NET 4.7
• Windows version: win10
• Does the bug reproduce also in WPF for .NET Framework 4.8?: Yes

• Is this bug related specifically to tooling in Visual Studio (e.g. XAML Designer, Code editing, etc...)? No

  Problem description:
  Modal dialog on top of non-modal window sends main window to back. Ie, when we close a child window its Owner gets send back (we lost focus)

  Actual behavior:
  The parent window lost focus after closing a child window after closing a modal.

  Expected behavior:
  No matter if a modal dialog has been shown before, if a user closes a child window, the parent window should stay visible.

  Minimal repro:
  Here is the problem and some source code to reproduce: https://stackoverflow.com/questions/10757625/why-does-closing-the-last-child-window-minimize-its-parent-window

[lindexi]

@lisberPontes Could you help me to check is it a same issue with https://github.com/dotnet/wpf/issues/2761

[lisberPontes]

@lisberPontes Could you help me to check is it a same issue with #2761

Hi @lindexi , I'm afraid is not the same problem. I've restore a quick video showing the problem. Just to add some context about it:

1. By clicking on an icon we open a child window (it's Owner is the Main Window)
2. We raise a Dialog box
3. We raise the .Close() on the Child Window, and by doing so the Main Window losses its focus.

[lindexi]

@lisberPontes Thank you. And I also find this problem and I write a demo in wpf-issues/ChildWindows at master · dotnet-campus/wpf-issues

The MainWindow will lose focus when close the sub window in WPF.