Delphi
Delphi

SetWindowPos causes taskbar button to flash

I need to make a form in an application always be the top z ordered form on a messy desktop, and explicitly set focus to an edit box in the form. When I call SetWindowPos it always brings the form to the topmost z position but the focus is set to the application's button on the taskbar which is flashing. I need that to stop and instead have focus appear in a waiting TEdit of the form.

Is there a work around for the behavior of SetWindowPos or another technique.

SetWindowPos(Self.Handle,
               HWND_TOPMOST,
               Top,
               Left,
               Width,
               Height,
               SWP_NOMOVE + SWP_NOSIZE)

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pcox9999Asked: 2009-07-10

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LVL 39

Geert GOracle dbaCommented: 2009-07-10

in the form properties set the formstyle to fsStayOnTop (you can do this in the IDE)

procedure TForm1.Test;
begin
Form2.ActiveControl := Form2.Edit1;
end;

pcox9999Author Commented: 2009-07-10

That won't work. Focus is on the taskbar button for the app. The taskbar button is flashing. This is the behavior of Windows SetWindowsPos. I tried using Windows.SetForegroundWindow(Self.Handle); but that too sets the application button on the taskbar to flash. The solution seems to be outside my app and in Windows. BTW, I am using Delphi 2007 and Windows XP Pro.

LVL 39

Geert GOracle dbaCommented: 2009-07-10

This means your app isn't the active app, and a window in your app has changed focus or z-order

Do you want your app to remain inactive ?

if you change your app to active first and then change the z-order this flashing shouldn't happen

pcox9999Author Commented: 2009-07-10

Doesn't help. Maybe I'm leaving something out of my code. Here is the FormShow method that is giving me a headache. Note that the extra call to SetForegroundWindow makes no difference if it is in or commented out.

Thanks.


procedure TfrmPatLookup.FormShow(Sender: TObject);
begin
 
  {set the z order for all the windows forms so this
   form is the topmost}
 
  Self.ActiveControl := Self.ePatient;
 
  SetWindowPos(Self.Handle,
               HWND_TOPMOST,
               Top,
               Left,
               Width,
               Height,
               SWP_NOMOVE + SWP_NOSIZE);
 
  SetForegroundWindow(Self.Handle);
 
  if Self.ePatient.CanFocus then
    Self.epatient.SetFocus;
end;

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LVL 39

Geert GOracle dbaCommented: 2009-07-11

in formshow, the form is not allways visible yet

you don't need to self. everything

try this:

TfrmPatLookup.FormStyle := fsStayOnTop; // This is a must !

type
TfrmPatLookup = class(TForm)
procedure FormShow(Sender: TObject);
private
procedure WMFormShow(var Msg: TMessage); message WM_USER;
end;

procedure TfrmPatLookup.FormShow(Sender: TObject);
begin
PostMessage(Handle, WM_USER, 0, 0);
end;

procedure TfrmPatLookup.WMFormShow(var Msg: TMessage); message WM_USER;
begin
BringToFront;
ActiveControl := ePatient;
end;

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