UIView * toView = (self.header1 == button)?self.header2 : self.header1;
//fromView 转场动画完成之后,会把自己主动重父亲控件中移除
//UIViewAnimationOptionShowHideTransitionViews 离场视图,隐藏起来,不会从父控件中移除
[UIView transitionFromView:fromView toView:toView duration:1 options:UIViewAnimationOptionTransitionFlipFromLeft|UIViewAnimationOptionShowHideTransitionViews completion:nil];
UIViewAnimationOptionRepeat = 1 << 3, // repeat animation indefinitely
UIViewAnimationOptionAutoreverse = 1 << 4, // if repeat, run animation back and forth
UIViewAnimationOptionShowHideTransitionViews = 1 << 8, // flip to/from hidden state instead of adding/removing
UIViewAnimationOptionCurveEaseInOut = 0 << 16, // default
UIViewAnimationOptionCurveEaseIn = 1 << 16,
UIViewAnimationOptionCurveEaseOut = 2 << 16,
UIViewAnimationOptionCurveLinear = 3 << 16,
UIViewAnimationOptionTransitionNone = 0 << 20, // default
UIViewAnimationOptionTransitionFlipFromLeft = 1 << 20,
UIViewAnimationOptionTransitionFlipFromRight = 2 << 20,
UIViewAnimationOptionTransitionCurlUp = 3 << 20,
UIViewAnimationOptionTransitionCurlDown = 4 << 20,
UIViewAnimationOptionTransitionCrossDissolve = 5 << 20,
UIViewAnimationOptionTransitionFlipFromTop = 6 << 20,
UIViewAnimationOptionTransitionFlipFromBottom = 7 << 20,
UIViewAnimationOptionLayoutSubviews //提交动画的时候布局子控件，表示子控件将和父控件一同动画。
