简单的动画

每一个控件都是一个容器 所以一个控件能放到另一个控件的内部 属性 @property(nonatomic) CGRect frame; @property(nonatomic) CGRect bounds; @property(nonatomic) CGPoint center; 方法 - (void)removeFromSuperview; - (void)insertSubview:(UIView *)view atIndex:(NSInteger)index; - (void)exchangeSubviewAtIndex:(NSInteger)index1 withSubviewAtIndex:(NSInteger)index2; - (void)addSubview:(UIView *)view; - (void)insertSubview:(UIView *)view belowSubview:(UIView *)siblingSubview; - (void)insertSubview:(UIView *)view aboveSubview:(UIView *)siblingSubview; - (void)bringSubviewToFront:(UIView *)view; - (void)sendSubviewToBack:(UIView *)view; 示例：