UIImageView動畫完成後的訪問方法

Question

我有一個圖像數組加載到UIImageView，我通過一個循環動畫。在顯示圖像後，我想要調用@selector以關閉當前的視圖控制器。使用此代碼的圖像動畫很好：

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]; 

在16秒後，我想要一個方法被調用。我看着UIView類的方法setAnimationDidStopSelector:，但我無法讓它與我目前的動畫實現一起工作。有什麼建議麼？

謝謝。

Answer 1

使用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

您可以創建一個計時器在動畫持續時間後觸發。回調可以處理動畫完成後要執行的邏輯。在您的回撥中，請務必檢查動畫[UIImageView isAnimating]的狀態，以防萬一您需要更多時間讓動畫完成。

Answer 3

在ImageView.m

- (void) startAnimatingWithCompleted:(void (^)(void))completedHandler { 
if (!self.isAnimating) { 
    [self startAnimating]; 
    dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, self.animationDuration * NSEC_PER_SEC); 
    dispatch_after(popTime, dispatch_get_main_queue(),completedHandler);  
}} 

Answer 4

有沒有辦法做到這一點恰恰與UIImageView的。使用延遲將在大部分時間都有效，但開始後可能會有一些延遲動畫在屏幕上發生之前調用動畫，因此它不精確。而不是使用UIImageView進行動畫嘗試使用CAKeyframeAnimation，它將在動畫完成時調用委託方法。沿着這些路線的東西：

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]; 

然後，只需執行animationDidStop委託方法

Answer 5

用這種方法你避免計時器火，而ImageView的仍然動畫由於緩慢的圖像加載。 你可以用這種方法同時使用performSelector: withObject: afterDelay:和GCD：

[self performSelector:@selector(didFinishAnimatingImageView:) 
      withObject:imageView 
      afterDelay:imageView.animationDuration]; 

/\self.imageView.animationDuration有startAnimating之前打賭配置，否則這將是0

比如果-(void)didFinishAnimatingImageView:創建一個後臺隊列，執行檢查isAnimating財產，比執行主隊列上的其餘部分

- (void)didFinishAnimatingImageView:(UIImageView*)imageView 
{ 

    dispatch_queue_t backgroundQueue = dispatch_queue_create("com.yourcompany.yourapp.checkDidFinishAnimatingImageView", 0); 
    dispatch_async(backgroundQueue, ^{ 

     while (self.imageView.isAnimating) 
      NSLog(@"Is animating... Waiting..."); 

     dispatch_async(dispatch_get_main_queue(), ^{ 

      /* All the rest... */ 

     }); 

    }); 

} 

Answer 6

您可以imple使用這一類UIImageView-AnimationCompletionBlock

而對於斯威夫特版本：UIImageView-AnimationImagesCompletionBlock

採取此類中自述文件看看..

添加的UIImageView + AnimationCompletion.h和的UIImageView + AnimationCompletion。米文件的項目，並將其導入的UIImageView + AnimationCompletion.h文件要使用這個..

對於如。

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 7

從GurPreet_Singh答（UIImageView的+ AnimationCompletion） 創建斯威夫特版本我沒能創造一個UIImageView的擴展，但我相信這是非常簡單易用。

class AnimatedImageView: UIImageView, CAAnimationDelegate { 

    var completion: ((_ completed: Bool) -> Void)? 

    func startAnimate(completion: ((_ completed: Bool) -> Void)?) { 
     self.completion = completion 
     if let animationImages = animationImages { 
      let cgImages = animationImages.map({ $0.cgImage as AnyObject }) 
      let animation = CAKeyframeAnimation(keyPath: "contents") 
      animation.values = cgImages 
      animation.repeatCount = Float(self.animationRepeatCount) 
      animation.duration = self.animationDuration 
      animation.delegate = self 

      self.layer.add(animation, forKey: nil) 
     } else { 
      self.completion?(false) 
     } 
    } 

    func animationDidStop(_ anim: CAAnimation, finished flag: Bool) { 
     completion?(flag) 
    } 
} 


let imageView = AnimatedImageView(frame: CGRect(x: 50, y: 50, width: 200, height: 135)) 
imageView.image = images.first 
imageView.animationImages = images 
imageView.animationDuration = 2 
imageView.animationRepeatCount = 1 
view.addSubview(imageView) 

imageView.startAnimate { (completed) in 
    print("animation is done \(completed)") 
    imageView.image = images.last 
}