How can I check if my application has focus?

Question

What I want to do is check if my application has focus because if it is not then I will popup an Alert Window just over the Notification Area to display some message to the end user.

score 18 · Accepted Answer · edited Jun 14 '13 at 16:29

18

Call Windows.GetForegroundWindow() and then pass the HWND to the Controls.FindControl() function. It will return a non-nil TWinControl pointer if the HWND belongs to your process. For example:

if FindControl(GetForegroundWindow()) <> nil then
  // has focus ...
else
  // does not have focus ...

edited Jun 14 '13 at 16:29

gabr

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answered Sep 14 '10 at 20:40

Remy Lebeau

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score 5 · Answer 2 · answered Jun 13 '16 at 14:38

5

D2007 has this useful property

if Application.Active then
//

answered Jun 13 '16 at 14:38

Anton Duzenko

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score 4 · Answer 3 · answered Sep 14 '10 at 20:21

If your application consists of a single form, then

GetForegroundWindow = Handle

will suffice. The expression above is true if and only if the your form is the foreground window, that is, if keyboard focus belongs to a control on this form (or to the form itself).

If your application consists of a number of forms, simply loop through them and check if any of them matches GetForegroundWindow.

score 0 · Answer 4 · answered Sep 25 '12 at 08:57

A slight variation on Remys response is:

Var
  Win: TWinControl;
Begin
  Win := FindControl(GetForegroundWindow);
  if Win <> nil then
//      StringGrid1.Row :=5;
//      StringGrid1.SetFocus;

compiled ok for me, but I found it unreliable during debug, the stringgrid.setfocus is called even when the window isn't focused causing an error.

How can I check if my application has focus?

4 Answers4