Keeping application/form active

Question

Our kiosk-mode application starts a forms-based utility using Process.Start(). On one device type, once in a while the main application gets activated directly after the start of the utility for some (unknown) reason, hiding the UI of the utility app. Is there a way to keep the utility activated? We're currently using TopMost = true, but that doesn't prevent the focus from beeing transfered to the main application, causing hotkeys not to behave as expected.

Workflow:

1. Application A currently displays a form (AnotherForm) opened with ShowDialog() somewhere in the app
2. AnotherForm contains a button that will start application B by calling Process.Start()
3. Application B opens a form (YetAnotherForm) using Application.Run()

Answer 1

I finally gave up and implemented a simple logic that prevents the utility form from beeing deactivated:

[Conditional("StrangeDeviceType")]
protected override void OnDeactivate(EventArgs e) 
{
  if (/* currently not terminating */) 
  {
    Activate();
  }
}

Answer 2

You are giving the Windows window manager a very hard time at guessing at the Right Way. The biggest issue is that, at the time you make the Process.Start() call, there are no windows in your process that can receive the focus. Your dialog just closed and no window is left. That's a very difficult problem to deal with, the window manager must move another window into the foreground so the user isn't stuck with having no active window at all.

The exact rules that it uses are not documented, I only know that time plays a factor. It gives the process a chance to create another window before it puts its foot down and picks a window of another process.

You make it extra complicated because you give it two windows to choose from. The window manager also allows a process to steal the foreground when it got started by the process that's active. Which one it will pick is now a crapshoot that's highly timing dependent. With pretty good odds that the process you started will lose since it will need some time to get itself initialized and display its window. Your YetAnotherForm would typically be quicker. So gets the foreground love.

Just don't force the window manager to have to make the choice. Display YetAnoterForm first, then start the process. You could use that form's Shown event for example.