How do I draw on a form and over a control. Screen has no canvas, obviously
the form canvas gets clipped...
I want to draw a rectangle which is displayed whilst dragging

Thanks in advance, please email me on joh...@iol.ie

On 26 Sep 1996 13:00:08 GMT, "John Cunningham" <joh...@iol.ie> wrote:

You can draw on the form's canvas, but you need to turn off clipping.
See SetWindowLong in the Windows API documentation. You need to set
the window style (Gwl_Style). See CreateWindow to learn about window
styles. Look for Ws_ClipChildren. Remember to turn clipping back on
when you are done drawing the rectangle.

Alternatively, you can change the form's canvas to a different DC, by
retrieving a DC from the cache, rather than using the form's own DC.
See GetDCEx for details (Dcx_Cache in particular).

--
Ray Lischner, Tempest Software, Corvallis, Oregon, USA
Author of Secrets of Delphi 2 (http://www.tempest-sw.com/secrets/)