Forms & Dialogs

From TeamDeveloperWiki

This page covers Form Window and DialogBox tips & tricks.

Contents 1 How to drag a window without a caption 2 How to force a window on the taskbar

How to drag a window without a caption

See Windows messages : How to drag a window without a caption

How to force a window on the taskbar

When a top-level window is created without a specific parent (hWndNULL) the window will be visible on the Windows taskbar.
Windows created using a parent, will not be shown.

To be able to use a parent while creating a window AND having it placed on the taskbar, use the following:
On creation of the window, set the GWL_EXSTYLE to WS_EX_APPWINDOW.

First declare these external functions and system constants:

Library name: USER32.DLL
   Function: GetWindowLongA
      Export Ordinal: 0
      Returns
         Number: LONG
      Parameters
         Window Handle: HWND
         Number: INT

   Function: SetWindowLongA
      Export Ordinal: 0
      Returns
         Number: LONG
      Parameters
         Window Handle: HWND
         Number: INT
         Number: LONG


Constants
   System
      Number: GWL_EXSTYLE	= -20
      Number: WS_EX_APPWINDOW	= 0x00040000

Now, set the WS_EX_APPWINDOW style to the window at creation:

On SAM_Create
   Call SetWindowLongA( hWndForm, GWL_EXSTYLE, GetWindowLongA( hWndForm, GWL_EXSTYLE ) | WS_EX_APPWINDOW )

The window will be shown on the taskbar.

Here you can download a sample:

• WIKI_ShowWindowOnTaskbar.zip