Determine if a control is showing

November 26, 2021

Lets say I have a pagecontrol with two tabsheet. There is a button on the first sheet but the active sheet is the second. In this case how can I determine if that button is showing (e.g. visible for the user) or not?
I tried the button’s Showing property, but for some reason its always True.

update: for the clarification I don’t mind if the control is outside of the desktop’s visible area or covered by any other application’s window.

>Solution :

You can simply go up in the VCL tree until you find an element which isn’t visible, or you have no other parent to check.

function IsVisible(Obj:TWinControl):boolean;
begin
  Result:=Obj.Visible;
  if not Obj.Visible then Exit;

  while Obj.HasParent do
  begin
    Obj:=Obj.Parent;
    Result:=Obj.Visible;
    if not Result then Exit;
  end;
end;