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

这里有一些不同的方法:UIAnimations,在我看来,这听起来像是你的挑战。

编辑:我太懒了:)

在这篇文章中,我提到了这个方法:

[newView setFrame:CGRectMake( 0.0f, 480.0f, 320.0f, 480.0f)]; //notice this is OFF screen!
[UIView beginAnimations:@"animateTableView" context:nil];
[UIView setAnimationDuration:0.4];
[newView setFrame:CGRectMake( 0.0f, 0.0f, 320.0f, 480.0f)]; //notice this is ON screen!
[UIView commitAnimations];

但是不是动画帧,而是动画alpha:

[newView setAlpha:0.0]; // set it to zero so it is all gone.
[UIView beginAnimations:@"animateTableView" context:nil];
[UIView setAnimationDuration:0.4];
[newView setAlpha:0.5]; //this will change the newView alpha from its previous zero value to 0.5f
[UIView commitAnimations];

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

这里有一些不同的方法:UIAnimations,在我看来,这听起来像是你的挑战。

编辑:我太懒了:)

在这篇文章中,我提到了这个方法:

[newView setFrame:CGRectMake( 0.0f, 480.0f, 320.0f, 480.0f)]; //notice this is OFF screen!
[UIView beginAnimations:@"animateTableView" context:nil];
[UIView setAnimationDuration:0.4];
[newView setFrame:CGRectMake( 0.0f, 0.0f, 320.0f, 480.0f)]; //notice this is ON screen!
[UIView commitAnimations];

但是不是动画帧,而是动画alpha:

[newView setAlpha:0.0]; // set it to zero so it is all gone.
[UIView beginAnimations:@"animateTableView" context:nil];
[UIView setAnimationDuration:0.4];
[newView setAlpha:0.5]; //this will change the newView alpha from its previous zero value to 0.5f
[UIView commitAnimations];

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)

斯威夫特5:

当处理collectionView时。只加载一个项目或多个项目的动画。当改变单元格图像时,我尝试了一些不同的动画选项,没有区别,所以我没有在这里指明动画名称。

UIView.animate(withDuration: 1.0) { [weak self] in
                guard let self = self else { return print("gotchya!") }
                self.collectionView.reloadItems(at: [indexPath])
            }
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;