iOS开发 - UIView动画扩展块(UIViewAnimationWithBlocks)

UIView类函数原型

@interface UIView(UIViewAnimationWithBlocks)

+ (void)animateWithDuration:(NSTimeInterval)duration delay:(NSTimeInterval)delay options:(UIViewAnimationOptions)options animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion NS_***AILABLE_IOS(4_0);

+ (void)animateWithDuration:(NSTimeInterval)duration animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion NS_***AILABLE_IOS(4_0); // delay = 0.0, options = 0

+ (void)animateWithDuration:(NSTimeInterval)duration animations:(void (^)(void))animations NS_***AILABLE_IOS(4_0); // delay = 0.0, options = 0, completion = NULL

+ (void)animateWithDuration:(NSTimeInterval)duration delay:(NSTimeInterval)delay usingSpringWithDamping:(CGFloat)dampingRatio initialSpringVelocity:(CGFloat)velocity options:(UIViewAnimationOptions)options animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion NS_***AILABLE_IOS(7_0);

+ (void)transitionWithView:(UIView *)view duration:(NSTimeInterval)duration options:(UIViewAnimationOptions)options animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion NS_***AILABLE_IOS(4_0);

+ (void)transitionFromView:(UIView *)fromView toView:(UIView *)toView duration:(NSTimeInterval)duration options:(UIViewAnimationOptions)options completion:(void (^)(BOOL finished))completion NS_***AILABLE_IOS(4_0);

+ (void)performSystemAnimation:(UISystemAnimation)animation onViews:(NSArray *)views options:(UIViewAnimationOptions)options animations:(void (^)(void))parallelAnimations completion:(void (^)(BOOL finished))completion NS_***AILABLE_IOS(7_0);

@end

UIView Animation 的参数详解

##

//设置动画持续的时间
[UIView setAnimationDuration:0.2];

//设置代理//动画块的某个方法(最下方),委托到本类的实例
[UIView setAnimationDelegate:self];

//动画结束后去执行的方
[UIView setAnimationDidStopSelector:@selector(resetView)];

//设置动画的次数
[UIView setAnimationRepeatCount:99999999];

//设置动画的方式
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];

//default = 0.0延迟多少时间开始执行动画
+ (void)setAnimationDelay:(NSTimeInterval)delay; 

//default = now ([NSDate date])动画开始日期
+ (void)setAnimationStartDate:(NSDate *)startDate; 

// //default = NO. YES的话,动画(非最后一次)结束后动态复原到最开始状态
+ (void)setAnimationRepeatAutoreverses:(BOOL)repeatAutoreverses;

//default = NO. YES,停止之前的动画,从现在这里开始新动画
+ (void)setAnimationBeginsFromCurrentState:(BOOL)fromCurrentState; 

//添加动画到view上,cache是YES的时候比较高效,但是动画过程中不能更新界面上的内容,NO时每一帧都重新画,可以实时更新
+ (void)setAnimationTransition:(UIViewAnimationTransition)transition forView:(UIView *)view cache:(BOOL)cache; 

//是否忽略一些动画设置
+ (void)setAnimationsEnabled:(BOOL)enabled;

UIViewAnimationWithBlocks动画扩展详解

函数原型

+ (void)animateWithDuration:(NSTimeInterval)duration animations:(void (^)(void))animations

例如一个视图淡出屏幕，另外一个视图出现的代码：

[UIView animateWithDuration:1.0 animations:^{
        firstView.alpha = 0.0;
        secondView.alpha = 1.0;
}];

实现连续的动画，只需在completion代码块中添加动画。

实例代码：

[UIView animateWithDuration:2.0
                 animations:^{
                     oldImageView.alpha = 0.0;
                     newImageView.alpha = 1.0;
                     //imageView.center = CGPointMake(500.0, 512.0);
                 }
                 completion:^(BOOL finished){
                     [UIView animateWithDuration:4.0
                                      animations:^{
                                          newImageView.center = CGPointMake(500.0, 512.0);
                                      }];
                 }];

UIView视图的动画功能，可以使在更新或切换视图时有放缓节奏、产生流畅的动画效果，进而改善用户体验。UIView可以产生动画效果的变化包括：

可以设置动画属性的有:

- frame            //大小变化：改变视图框架（frame）和边界。
 - bounds           //拉伸变化：改变视图内容的延展区域。
 - center           //居中显示
 - transform        //旋转：即任何应用到视图上的仿射变换（transform）
 - alpha            //改变透明度：改变视图的alpha值。
 - backgroundColor  //改变背景颜色
 - contentStretch   //拉伸内容

其中：

1. duration   //为动画持续的时间。 
 2. animations //为动画效果的代码块。
 3. completion //为动画执行完毕以后执行的代码块
 4. options    //为动画执行的选项
 5. delay      //为动画开始执行前等待的时间