Im trying to fix a bug in a BView derived class which is causing a crash whenever the Draw() method is called for a second or more time. It works OK the first time (when the object is first created) but subsequent calls via Invalidate() cause a crash.
After Googling it seems its necessary to lock the parent window but nothing Ive tried works.
Ive tried
(Window())->LockLooper()
(Window())->UnlockLooper()
and
(Window())->Lock()
(Window())->Unlock()
and numerous other things without success.
The full code for Draw() is here:
void SpeedoDial::Draw(BRect arect)
{
//lock here?
MovePenTo(0,0);
SetDrawingMode(B_OP_ALPHA);
SetBlendingMode(B_PIXEL_ALPHA,B_ALPHA_OVERLAY);
if (backend->getMPHMode())
{
DrawBitmap(MPHdialimg);
}
else
{
DrawBitmap(KMHdialimg);
}
//unlock here?
}
Im sure Im doing something very simple wrong?
Thanks
Andrew
