Question

I am repeatedly drawing to an offscreen bitmap context non-destructivly on iphone. Right now the only way I have figured out to get it to display is to update the drawRect of my UIView with the contents of the context. This runs really slow and seems unnecessary. Does any one know of a way to have the bitmap update on the screen without force refreshing the whole thing?

Answer 1

Call UIView’s this method for updation

- (void)setNeedsDisplayInRect:(CGRect)invalidRect

invalidRect is Rectangle part that has been changed…