我有一个带有图像的UIImageView。现在我有一个全新的图像(图形文件),并想要在这个UIImageView中显示它。如果我设置

myImageView.image = newImage;

新图像立即可见。不可以做成动画。

我想让它很好地淡出到新图像中。我想也许有比在上面创建一个新的UIImageView并与动画混合更好的解决方案?


当前回答

这太棒了

  self.imgViewPreview.transform = CGAffineTransform(scaleX: 0, y: 0)
          UIView.animate(withDuration: 1, delay: 0, usingSpringWithDamping: 0.3, initialSpringVelocity: 0, options: .curveEaseOut, animations: {
              self.imgViewPreview.image = newImage
              self.imgViewPreview.transform = .identity
          }, completion: nil)

其他回答

使用Swift 3

extension UIImageView{   
 var imageWithFade:UIImage?{
        get{
            return self.image
        }
        set{
            UIView.transition(with: self,
                              duration: 0.5, options: .transitionCrossDissolve, animations: {
                                self.image = newValue
            }, completion: nil)
        }
    }
}

用法:

myImageView.imageWithFade = myImage

为什么不试试这个呢?

NSArray *animationFrames = [NSArray arrayWithObjects:
  [UIImage imageWithName:@"image1.png"],
  [UIImage imageWithName:@"image2.png"], 
  nil];

UIImageView *animatedImageView = [[UIImageView alloc] init];
animatedImageView.animationImages = animationsFrame;
[animatedImageView setAnimationRepeatCount:1];
[animatedImageView startAnimating];

快速版本:

let animationsFrames = [UIImage(named: "image1.png"), UIImage(named: "image2.png")]
let animatedImageView = UIImageView()
animatedImageView.animationImages = animationsFrames
animatedImageView.animationRepeatCount = 1
animatedImageView.startAnimating()
CABasicAnimation* fadeAnim = [CABasicAnimation animationWithKeyPath:@"contents"];
fadeAnim.fromValue = (__bridge id)imageView.image.CGImage;
fadeAnim.toValue = (__bridge id)[UIImage imageNamed:@"newImage.png"].CGImage;
fadeAnim.duration = 2.0;
[imageView.layer addAnimation:fadeAnim forKey:@"contents"];
imageView.layer.contents = (__bridge id)[UIImage imageNamed:@"newImage.png"].CGImage;
[UIView transitionWithView:textFieldimageView
                  duration:0.2f
                   options:UIViewAnimationOptionTransitionCrossDissolve
                animations:^{
                    imageView.image = newImage;
                } completion:nil];

是另一种可能性

在iOS 5中,这就简单多了:

[newView setAlpha:0.0];
[UIView animateWithDuration:0.4 animations:^{
    [newView setAlpha:0.5];
}];