Prevent a form from getting focus

Scott

I am making an application that uses multiple forms at the same time. I have one form that is a "background" form for all the others. The problem is that when I click it, the form comes to the front. I want to keep it behind my other forms, but still in front of other windows that may be open (other running applications). How do I do this?

5 Replies

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Alan18y ago
The code is for the activation of the entire application.

For individual forms you can handle the .NET Form.Activated or Form.Deactivate events.
Scott18y ago
That's not quite what I'm looking for, but I'll play around with it and see what I can do with it. Is that code for the activation of each individual form or for the entire application?
Alan18y ago
To my knowledge, there's no such event in the .NET framework.

However, you can override WndProc() in the form class you'd like to keep on top (or not) to watch for the WM_ACTIVATEAPP message and then handle it accordingly. Something like this:

private const int WM_ACTIVATEAPP = 0x1C;

protected override void WndProc(ref Message m)
{
   if (m.Msg == WM_ACTIVATEAPP)
   {
      if ( m.WParam.ToInt32() != 0 )
      {
         // application is receiving focus
         this.Topmost = true;
      }
      else
      {
         // application is losing focus
         this.Topmost = false;
      }
   }

   base.WndProc(ref m);
}
Scott18y ago
I already tried that, but when I click on another application in the taskbar, my application is still on top. Is there an event that fires when the application loses focus?
Bechir Bejaoui18y ago
set the property TopMost of the from that you want to be always on top to true
yourForm.TopMost = true;