按比例来缩放视图:CGAffineTransformMakeScale
将下列代码添加到view didload方法里:
self.view.transform = CGAffineTransformMakeScale(1.0f, 1.0f);//将要显示的view按照正常比例显示出来
[UIView beginAnimations:nil context:UIGraphicsGetCurrentContext()];
[UIView setAnimationCurve:UIViewAnimationCurveEaseIn]; //InOut 表示进入和出去时都启动动画
[UIView setAnimationDuration:0.5f];//动画时间
self.view.transform=CGAffineTransformMakeScale(0.01f, 0.01f);//先让要显示的view最小直至消失
[UIView commitAnimations]; //启动动画