我需要在动态创建的视图中绘制形状/线条。这是我正在尝试的代码,但尽管正在添加视图,但它没有绘制任何内容。
//loc1 and loc2 are the touch locations on the view used to draw a rect
UIView *vw = [[UIView alloc] initWithFrame:CGRectMake(loc1.x, loc1.y,loc2.x - loc1.x, loc2.y - loc1.y)];
UIGraphicsBeginImageContext(vw.bounds.size);
CGContextRef ctx = UIGraphicsGetCurrentContext();
CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 0.0/255.0, 0.0/255.0, 255.0/255.0, 1.0);
CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 2);
CGContextAddRect(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, 50, 50));
CGContextStrokePath(UIGraphicsGetCurrentContext());
UIGraphicsEndImageContext();
[mainImageView addSubview:vw];