// swift举例:
label.transform =CGAffineTransformMakeRotation(0.2)// 旋转视图
label3.adjustsFontSizeToFitWidth =true //根据label的宽度,改变字体的大小
label3.addGestureRecognizer(tap)
label3.shadowColor =UIColor.purpleColor()//设置shadow
label3.shadowOffset =CGSize(width: 2, height:2)
// 给view的layer属性添加动画
[[self.view layer] addAnimation:animationforKey:@"animation"];