UIImageView动画完成后的访问方法

Question

我有一个图像数组加载到UIImageView中,我通过一个循环动画.显示图像后,我想@selector调用一个以关闭当前视图控制器.使用以下代码可以很好地动画图像:

NSArray * imageArray = [[NSArray alloc] initWithObjects:
                        [UIImage imageNamed:@"HowTo1.png"], 
                        [UIImage imageNamed:@"HowTo2.png"],
                        nil];
UIImageView * instructions = [[UIImageView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

instructions.animationImages = imageArray;
[imageArray release];
instructions.animationDuration = 16.0;
instructions.animationRepeatCount = 1;
instructions.contentMode = UIViewContentModeBottomLeft;
[instructions startAnimating];
[self.view addSubview:instructions];
[instructions release];

16秒后,我想要一个方法来调用.我查看了UIView类方法,setAnimationDidStopSelector:但我无法使用它来处理当前的动画实现.有什么建议？

谢谢.

Answer 1

用途performSelector:withObject:afterDelay::

[self performSelector:@selector(animationDidFinish:) withObject:nil
    afterDelay:instructions.animationDuration];

或使用dispatch_after:

dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, instructions.animationDuration * NSEC_PER_SEC);
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
    [self animationDidFinish];
});

Answer 2

你可以简单地使用这个类别UIImageView-AnimationCompletionBlock

而对于Swift版本:UIImageView-AnimationImagesCompletionBlock

看看这堂课中的自述文件..

在项目中添加UIImageView + AnimationCompletion.h和UIImageView + AnimationCompletion.m文件,然后导入UIImageView + AnimationCompletion.h文件,在这里你要使用它.

例如.

NSMutableArray *imagesArray = [[NSMutableArray alloc] init];
for(int i = 10001 ; i<= 10010 ; i++)
    [imagesArray addObject:[UIImage imageNamed:[NSString stringWithFormat:@"%d.png",i]]];

self.animatedImageView.animationImages = imagesArray;
self.animatedImageView.animationDuration = 2.0f;
self.animatedImageView.animationRepeatCount = 3;
[self.animatedImageView startAnimatingWithCompletionBlock:^(BOOL success){
 NSLog(@"Animation Completed",);}];

Answer 3

用UIImageView无法做到这一点.使用延迟大部分时间都可以工作,但是在动画发生在屏幕上之前调用startAnimating后可能会有一些延迟,所以它不精确.而不是使用UIImageView进行此动画尝试使用CAKeyframeAnimation,它将在动画完成时调用委托方法.这些方面的东西:

NSArray * imageArray = [[NSArray alloc] initWithObjects:
                    (id)[UIImage imageNamed:@"HowTo1.png"].CGImage, 
                    (id)[UIImage imageNamed:@"HowTo2.png"].CGImage,
                    nil];
UIImageView * instructions = [[UIImageView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

//create animation
CAKeyframeAnimation *anim = [CAKeyframeAnimation animation];
[anim setKeyPath:@"contents"];
[anim setValues:imageArray];

[anim setRepeatCount:1];
[anim setDuration:1];
anim.delegate = self; // delegate animationDidStop method will be called

CALayer *myLayer = instructions.layer;

[myLayer addAnimation:anim forKey:nil];

然后只需实现animationDidStop委托方法