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Hi Can someone give me a point in the right direction. I want to attach my form on top of another Win32 application and make it synchronized. I can handle the window position using a timer and unmanaged code (import of user32.dll) but my window stay on top of all windows :) not just the window I want it to be on top of. Make sense?

Mike Gold · Answer

I don't think you need to use a timer just respond to the Move event of the form. Also show the Window on the Activate event and hide on the Deactivate. Also Activate() the child window when its up. Make sure you set your StartPosition property to Manual and set the location of your child window each time you move it. All in all I would recommend using a User Control instead of a Window tracking your application. private void StickChildInCenter() { _child.SetBounds( this .Left + (ClientRectangle.Width - _child.ClientRectangle.Width)/2 this .Top + (ClientRectangle.Height - _child.ClientRectangle.Height)/2 _child.Width _child.Height); } private void Form1_Move( object sender System.EventArgs e) { StickChildInCenter(); _child.Activate(); _child.Show(); } private void Form1_Activated( object sender System.EventArgs e) { _child.Activate(); _child.Show(); } } Although you may notice a small shift when the form moves quickly. If you want to avoid this you may need to hide the child form when it is moving and paint a bitmap of the child form onto the form during the move. -Mike G.