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?
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
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
其他回答
在iOS 5中,这就简单多了:
[newView setAlpha:0.0];
[UIView animateWithDuration:0.4 animations:^{
[newView setAlpha:0.5];
}];
我不确定你是否可以用渐隐效果动画UIViews,因为似乎所有支持的视图转换都在UIViewAnimationTransition枚举中定义。渐变效果可以使用CoreAnimation实现。该方法的示例示例:
#import <QuartzCore/QuartzCore.h>
...
imageView.image = [UIImage imageNamed:(i % 2) ? @"3.jpg" : @"4.jpg"];
CATransition *transition = [CATransition animation];
transition.duration = 1.0f;
transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
transition.type = kCATransitionFade;
[imageView.layer addAnimation:transition forKey:nil];
弗拉基米尔的答案是完美的,但任何像我这样正在寻找快速解决方案的人
该方案适用于swift 4.2版本
var i = 0
func animation(){
let name = (i % 2 == 0) ? "1.png" : "2.png"
myImageView.image = UIImage.init(named: name)
let transition: CATransition = CATransition.init()
transition.duration = 1.0
transition.timingFunction = CAMediaTimingFunction.init(name: .easeInEaseOut)
transition.type = .fade
myImageView.layer.add(transition, forKey: nil)
i += 1
}
您可以在任何地方调用此方法。它将改变图像到下一个(图像)与动画。
对于Swift 4.0版本使用波纹管解决方案
var i = 0
func animationVersion4(){
let name = (i % 2 == 0) ? "1.png" : "2.png"
uiImage.image = UIImage.init(named: name)
let transition: CATransition = CATransition.init()
transition.duration = 1.0
transition.timingFunction = CAMediaTimingFunction.init(name: kCAMediaTimingFunctionEaseInEaseOut)
transition.type = kCATransitionFade
uiImage.layer.add(transition, forKey: nil)
i += 1
}
下面是Swift中的一个例子,它将首先交叉溶解一个新图像,然后添加一个弹性动画:
var selected: Bool {
willSet(selected) {
let expandTransform:CGAffineTransform = CGAffineTransformMakeScale(1.15, 1.15);
if (!self.selected && selected) {
UIView.transitionWithView(self.imageView,
duration:0.1,
options: UIViewAnimationOptions.TransitionCrossDissolve,
animations: {
self.imageView.image = SNStockCellSelectionAccessoryViewImage(selected)
self.imageView.transform = expandTransform
},
completion: {(finished: Bool) in
UIView.animateWithDuration(0.4,
delay:0.0,
usingSpringWithDamping:0.40,
initialSpringVelocity:0.2,
options:UIViewAnimationOptions.CurveEaseOut,
animations: {
self.imageView.transform = CGAffineTransformInvert(expandTransform)
}, completion:nil)
})
}
}
}
var imageView:UIImageView
如果imageView被正确地作为子视图添加到视图中,在selected = false到selected = true之间切换应该用一个弹性动画交换图像。SNStockCellSelectionAccessoryViewImage只是根据当前的选择状态返回一个不同的图像,如下所示:
private let SNStockCellSelectionAccessoryViewPlusIconSelected:UIImage = UIImage(named:"PlusIconSelected")!
private let SNStockCellSelectionAccessoryViewPlusIcon:UIImage = UIImage(named:"PlusIcon")!
private func SNStockCellSelectionAccessoryViewImage(selected:Bool) -> UIImage {
return selected ? SNStockCellSelectionAccessoryViewPlusIconSelected : SNStockCellSelectionAccessoryViewPlusIcon
}
下面的GIF例子有点慢,实际的动画发生得更快:
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()