用CGAffineTransform进行缩放并设置锚点
如果我正确地理解用CGAffineTransform
缩放一个UIView
锚定转换到其中心。
尤其是:
self.frame = CGRectMake(0,0,100,100); self.transform = CGAffineTransformMakeScale(2, 2); NSLog(@"%f;%f;%f;%f", self.frame.origin.x, self.frame.origin.y, self.frame.size.width, self.frame.size.height);
打印:
-50;-50;200;200
你如何创build一个使用特定锚点(比如0; 0)的CGAffineTransform比例?
(一个)
缩放然后翻译?
就像是 :
CGAffineTransform t = CGAffineTransformMakeScale(2, 2); t = CGAffineTransformTranslate(t, width/2, height/2); self.transform = t;
(b)中
设置锚点(这可能是你真正想要的)
[self layer].anchorPoint = CGPointMake(0.0f, 0.0f); self.transform = CGAffineTransformMakeScale(2, 2);
(C)
再次设置中心,以确保它在同一个地方?
CGPoint center = self.center; self.transform = CGAffineTransformMakeScale(2, 2); self.center = center;
首先#import <QuartzCore/QuartzCore.h>
,然后设置你的视图的锚点:
[[self layer] setAnchorPoint:CGPointMake(0, 0)];