Hi,
I've just committed the initial code for an -onPaint event handler for windows.
This allows you full control when painting a window. In many cases the current
Graphic control is adequate, but for more complicated problems (for example
child windows with scroll bars) more control is needed. The event handler calls
the windows API BeginPaint and EndPaint, so other than the logic to paint the
window no other action is required.
The main work is done in GUI_MessageLoops.cpp - but should it be done in
Window.xs?
We (Glenn and I) have been doing some playing/testing and it seems to work
well. We also have had some discussions to what should be passed as parameters
to the hander. Currently the parameters that are passed are the window and the
DC. The DC parameter could potentially removed, since in almost all cases the
window DC and the DC to be painted are always the same (the only exception
seems to be when the -noflicker option is used). The bounding rectangle of the
area to be redrawn could also be passed. In most cases this bounding rectangle
is not required since in typical usage you repaint the entire window (by a
BitBlt), the clipping region is created automatically before the event is
called.
Usage:
-onPaint => \&Paint,
sub Paint {
my ($win,$dc)[EMAIL PROTECTED];
#paint into the passed DC
}
Comments?
Cheers,
jez.
