Home/ Questions/Q 788463
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-14T21:22:09+00:00

I’ve got a C# winforms application that runs in the background, listening for hotkeys

  • 0

I’ve got a C# winforms application that runs in the background, listening for hotkeys to be pressed. When a hotkey is pressed, my form makes a brief appearance. The form is always running, but set to hidden until I receive a hotkey event, at which time I set the visible property to true. The code looks like this:

void hook_volumeDown(object sender, KeyPressedEventArgs e)
{
    this.Visible = true;
}

It should be noted that the topmost property of this form is set to true.

The really odd part is, after my C# app has stolen focus from another application, it will never do it again. For example: I launch my app, then launch some fullscreep app like Team Fortress 2. Then I press my hotkey. Team Fortress 2 minimizes, and I see my form. Then, however, I can restore TF2, and press my hotkey again all I want (with the desired effect), and TF2 will remain focused.

At any rate, I’m looking for a way to fix this. I’ve found a lot of questions here covering similar problems, but all of them are related to creating/launching a new form, not making an existing one visible (unless I missed something). I could rework the application to create a new form every time I need one, but that would entail creating yet another form to be invisible all the time just to wait for hotkey events, so I’d rather leave it as it is.

Any ideas?

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    I think you problem is related to the fact that Visible = true behaves differently between the first and subsequent calls. The first time visible is called and the window handle has not been created, the Window is created by calling CreateWindowEx which has some style parameters which controls how the window should behave. I think you need to make sure that the window is created with the style WS_EX_NOACTIVATE, which you can do by overriding CreateParams.

    Other things to try out:

    1) The ShowWindow function (used by Visible = true) ignores the focus parameter the first time it is called (http://msdn.microsoft.com/en-us/library/ms633548%28VS.85%29.aspx) if the program provides a STARTUPINFO structure. Dig into reflector and find out if the Form class provides a STARTUPINFO structure and if so, how to manipulate it.

    2) The Form has a ShowWithoutActivation property than can be overriden and set to true, have you overriden this?

    Sorry for the “no exact answer”, but I hope this at least gives you some starting points for further investigation. Good luck.

    • 0