延迟动画 – Objective-C答案

【问题标题】：Delay an animation – Objective-C延迟动画 – Objective-C
【发布时间】：2013-02-18 15:21:19
【问题描述】：

我正在使用以下代码为圆设置动画。但是，它一直在闪烁。我想将动画的重启延迟 5 秒。我该怎么做？

-(void)start
{    
    [self removeExistingAnimation];
    
    //create the image
    UIImage* img = [UIImage imageNamed:@"redCircle.png"];
    imageView = [[UIImageView alloc] initWithImage:img];
    imageView.frame = CGRectMake(0, 0, 0, 0);
    [self addSubview:imageView];
    
    //opacity animation setup
    CABasicAnimation *opacityAnimation;
    
    opacityAnimation=[CABasicAnimation animationWithKeyPath:@"opacity"];
    opacityAnimation.duration = ANIMATION_DURATION;
    opacityAnimation.repeatCount = ANIMATION_REPEAT;
    //theAnimation.autoreverses=YES;
    opacityAnimation.fromValue = [NSNumber numberWithFloat:0.6];
    opacityAnimation.toValue = [NSNumber numberWithFloat:0.025];
    //resize animation setup
    CABasicAnimation *transformAnimation;
    
    transformAnimation = [CABasicAnimation animationWithKeyPath:@"transform.scale"];
    
    transformAnimation.duration = ANIMATION_DURATION;
    transformAnimation.repeatCount = ANIMATION_REPEAT;
    //transformAnimation.autoreverses=YES;
    transformAnimation.fromValue = [NSNumber numberWithFloat:MIN_RATIO];
    transformAnimation.toValue = [NSNumber numberWithFloat:MAX_RATIO];
    
    //group the two animation
    CAAnimationGroup *group = [CAAnimationGroup animation];
    
    group.repeatCount = ANIMATION_REPEAT;
    [group setAnimations:[NSArray arrayWithObjects:opacityAnimation, transformAnimation, nil]];
    group.duration = ANIMATION_DURATION;

    //apply the grouped animaton
    [imageView.layer addAnimation:group forKey:@"groupAnimation"];
}

【问题讨论】：

标签： iphone objective-c cocoa-touch

【解决方案1】：

这样做：

-(void)start
{    
    [self removeExistingAnimation];

    //create the image
    UIImage* img = [UIImage imageNamed:@"redCircle.png"];
    imageView = [[UIImageView alloc] initWithImage:img];
    imageView.frame = CGRectMake(0, 0, 0, 0);
    [self addSubview:imageView];

    [self doAnimation];

    [NSTimer scheduledTimerWithTimeInterval:5.0 target:self selector:@selector(doAnimation) userInfo:nil repeats:YES];
}

-(void)doAnimation
{

//opacity animation setup
    CABasicAnimation *opacityAnimation;

    opacityAnimation=[CABasicAnimation animationWithKeyPath:@"opacity"];
    opacityAnimation.duration = ANIMATION_DURATION;
    opacityAnimation.repeatCount = ANIMATION_REPEAT;
    //theAnimation.autoreverses=YES;
    opacityAnimation.fromValue = [NSNumber numberWithFloat:0.6];
    opacityAnimation.toValue = [NSNumber numberWithFloat:0.025];
    //resize animation setup
    CABasicAnimation *transformAnimation;

    transformAnimation = [CABasicAnimation animationWithKeyPath:@"transform.scale"];

    transformAnimation.duration = ANIMATION_DURATION;
    transformAnimation.repeatCount = ANIMATION_REPEAT;
    //transformAnimation.autoreverses=YES;
    transformAnimation.fromValue = [NSNumber numberWithFloat:MIN_RATIO];
    transformAnimation.toValue = [NSNumber numberWithFloat:MAX_RATIO];

    //group the two animation
    CAAnimationGroup *group = [CAAnimationGroup animation];

    group.repeatCount = ANIMATION_REPEAT;
    [group setAnimations:[NSArray arrayWithObjects:opacityAnimation, transformAnimation, nil]];
    group.duration = ANIMATION_DURATION;

    //apply the grouped animaton
    [imageView.layer addAnimation:group forKey:@"groupAnimation"];

}

这看起来像肮脏的方法，但对我有用，希望对你有帮助..

【讨论】：

@MuhammadUmar 这个动画你用的是哪个框架？
石英核心。如果我删除 opacityAnimation.duration = ANIMATION_DURATION; 它会起作用和其他动画持续时间，但动画停止时仍然存在一个错误，imageView 仍然添加到 self 中，我可以看到大红圈。我想删除这个圆圈，比如 atEndAnimation 调用函数 removeExistingAnimation
是的，如果您删除所有持续时间代码，您的工作正常。
但是你让它一直在闪烁，你想让它在闪烁后结束吗？在我的代码中，我看到它完美地闪烁。
最小和最大比率的值是多少？

【解决方案2】：

这不是更干净一点吗？或者你有什么理由不能使用块来制作动画？

    - (void) start {
        //create the image
        UIImage* img = [UIImage imageNamed:@"redCircle.png"];
        imageView = [[UIImageView alloc] initWithImage:img];
        [self addSubview:imageView];

        [self animateWithDelay:0.0];
    }

    - (void) animateWithDelay:(CGFloat)delay {

        imageView.alpha = 0.0;
        imageView.transfrom = CGAffineTransformScale(myImage.transform, MIN_RATIO, MIN_RATIO);
        [UIImageView animateWithDuration:ANIMATION_DURATION delay:delay options:0 animations:^{

            imageView.alpha = 1.0;
            imageView.transfrom = CGAffineTransformScale(myImage.transform, MAX_RATIO, MAX_RATIO);

        } completion:^{
            animationCount++;
            if (ANIMATION_REPEAT != animationCount) {
                [self animateWithDelay:5.0];
            }
        }]; 

    }

你应该在你的类的某个地方定义animationCount，这样你就知道他什么时候应该停止重复。

（未测试，因此可能包含一些错误）

【讨论】：