Question

正如我在Apple documentation中读到的那样，我可以为UIView的'center'属性设置动画。

我正在使用CAKeyframeAnimation来执行此操作，并为该动画提供三个关键帧和三个CGPoint。

动画似乎不起作用。我在这里做错什么了吗？

NSMutableArray* values = [NSMutableArray new];
[values addObject:@(CGPointMake(0, 0))];
[values addObject:@(CGPointMake(5, 8))];
[values addObject:@(CGPointMake(10, 8))];

NSMutableArray* keyTimes = [NSMutableArray new];
[keyTimes addObject:@(0)];
[keyTimes addObject:@(0.5)];
[keyTimes addObject:@(1)];

NSMutableArray* timingFunctions = [NSMutableArray new];
[timingFunctions addObject:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut]];
[timingFunctions addObject:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut]];

CAKeyframeAnimation* myAimation = [CAKeyframeAnimation animationWithKeyPath:@"center"];
myAimation.duration             = 0.5;
myAimation.values               = values;
myAimation.timingFunctions      = timingFunctions;
myAimation.keyTimes             = keyTimes;

[myView.layer addAnimation:myAimation forKey:nil];

Answer 1

尝试将键路径从“中心”更改为“位置” 我的快速代码正在与此配合使用

    func animate() {
    var values: [AnyHashable] = []
    values.append(NSValue(cgPoint: CGPoint(x: 0, y: 0)))
    values.append(NSValue(cgPoint: CGPoint(x: 200, y: 140)))
    values.append(NSValue(cgPoint: CGPoint(x: 140, y: 200)))

    var keyTimes: [NSNumber] = []
    keyTimes.append(NSNumber(value: 0))
    keyTimes.append(NSNumber(value: 0.5))
    keyTimes.append(NSNumber(value: 1))

    var timingFunctions: [AnyHashable] = []
    timingFunctions.append(CAMediaTimingFunction(name: .easeOut))
    timingFunctions.append(CAMediaTimingFunction(name: .easeInEaseOut))

    let myAimation = CAKeyframeAnimation(keyPath: "position")
    myAimation.duration = 0.5
    myAimation.values = values
    myAimation.timingFunctions = timingFunctions as? [CAMediaTimingFunction]
    myAimation.keyTimes = keyTimes       
    myView.layer.add(myAimation, forKey: nil)
    }

Answer 2

该功能不起作用，因为center不是CALayer的属性。

您可以从this answer

查看完整列表

您也可以从苹果网站https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/CoreAnimation_guide/AnimatableProperties/AnimatableProperties.html#//apple_ref/doc/uid/TP40004514-CH11-SW1

上阅读

尝试[CAKeyframeAnimation animationWithKeyPath:@"position.x"];。

如何为UIViews的“中心”属性设置动画？

2 个答案: