361Transparent Background of Custom Drawing Class
Usually common problems already have simple solution. Like that one:
Problem
You subclassed UIView, you want to do some custom drawing in drawRect, but no matter what you do or where you draw, the background of the view remains black.
And not like that
– adding “self.opaque = NO;” in the drawRect: function
– CGContextClearRect(context, rect);
– CGContextSetAlpha(context, 0.5f);
- (void)drawRect:(CGRect)rect {
// Drawing code
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetRGBFillColor(context, 0.0, 0.0, 1.0, 1.0);
CGContextFillEllipseInRect(context, rect);
}
Solution
In the ViewController, which call the drawing class, add
myDrawingClass.opaque = NO;
– or even nicer. In the drawing class’ init function:
self.opaque = NO;