Ios CAShapeLayer动画没有'；不要停留在屏幕上，而是消失

我试图画一个动画圆圈，但每个部分都需要另一种颜色。现在一切都正常了，除了在我再次调用该方法之前刚刚绘制的片段消失了，所以只有最后一部分保留了下来。我不希望这样，我希望在4次之后，用不同的颜色笔划画出一个完整的圆

我怎样才能修复它，使它不会消失

这是我的初始代码：

- (void)_initCircle {
    _circle = [CAShapeLayer layer];
    _radius = 100;

    // Make a circular shape
    _circle.path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(0, 0, 2.0 * _radius, 2.0 * _radius) cornerRadius:_radius].CGPath;

    // Center the shape in self.view
    _circle.position = CGPointMake(CGRectGetMidX(self.view.frame) - _radius,
                                   CGRectGetMidY(self.view.frame) - _radius);

    _circle.fillColor = [UIColor clearColor].CGColor;
    _circle.lineWidth = 5;

    // Add to parent layer
    [self.view.layer addSublayer:_circle];
}

这是我的画：

- (void)_drawStrokeOnCircleFrom:(float)start to:(float)end withColor:(UIColor *)color {
    // Configure the apperence of the circle
    _circle.strokeColor = color.CGColor;
    _circle.strokeStart = start;
    _circle.strokeEnd = end;

       [CATransaction begin];

    // Configure animation
    CABasicAnimation *drawAnimation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];
    drawAnimation.duration            = 2.0; // "animate over 10 seconds or so.."
    drawAnimation.repeatCount         = 1.0;  // Animate only once..

    // Animate from no part of the stroke being drawn to the entire stroke being drawn
    drawAnimation.fromValue = [NSNumber numberWithFloat:start];
    drawAnimation.toValue   = [NSNumber numberWithFloat:end];

    // Experiment with timing to get the appearence to look the way you want
    drawAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];

    [CATransaction setCompletionBlock:^{
        NSLog(@"Complete animation");
        _index++;
        if(_index < _votes.count){
        _startStroke = _endStroke;
        _endStroke += [_votes[_index] floatValue] / _totalListens;
        [self _drawStrokeOnCircleFrom:_startStroke to:_endStroke withColor:_colors[_index]];
        }

    }];

    // Add the animation to the circle
    [_circle addAnimation:drawAnimation forKey:@"drawCircleAnimation"];

       [CATransaction commit];
}

-（void）\u drawStrokeOnCircleFrom:（float）开始到：（float）结束于color:（UIColor*）color{
//配置圆的外观
_circle.strokeColor=color.CGColor；
_circle.strokeStart=开始；
_circle.strokeEnd=结束；
[交易开始]；
//配置动画
CABasicAnimation*drawAnimation=[CABasicAnimation animationWithKeyPath:@“strokeEnd”]；
drawAnimation.duration=2.0；/“动画制作时间超过10秒左右…”
drawAnimation.repeatCount=1.0；//仅设置一次动画。。
//从正在绘制的笔划的任何部分到正在绘制的整个笔划设置动画
drawAnimation.fromValue=[NSNumber numberWithFloat:start]；
drawAnimation.toValue=[NSNumber numberWithFloat:end]；
//尝试计时，让外观看起来像你想要的样子
drawAnimation.timingFunction=[CamediaTimingFunctionWithName:KCAMediaTimingFunctionAsein]；
[CATTransaction setCompletionBlock:^{
NSLog（“完整动画”）；
_索引++；
如果（指数<票数）{
_开始行程=_结束行程；
_endStroke+=[\u投票[\u指数]浮动值]/\u总计；
[self _DrawStrokeonCirclefom:_StartStroketo:_EndStrokeWith Color:_colors[_index]]；
}
}];
//将动画添加到圆中
[_circleaddanimation:drawAnimation forKey:@“drawCircleAnimation”]；
[CATransaction-commit]；
}

尝试在您的CABasicAnimation上设置这些值：

drawAnimation.removedOnCompletion = NO;
drawAnimation.fillMode = kCAFillModeForwards;

---

我用这样的附加层解决了这个问题：

- (void)_drawStrokeOnCircle {

    [self _initCircle];

    [CATransaction begin];

    for (NSUInteger i = 0; i < 4; i++)
    {
        CAShapeLayer* strokePart = [[CAShapeLayer alloc] init];
        strokePart.fillColor = [[UIColor clearColor] CGColor];
        strokePart.frame = _circle.bounds;
        strokePart.path = _circle.path;
        strokePart.lineCap = _circle.lineCap;
        strokePart.lineWidth = _circle.lineWidth;


        // Configure the apperence of the circle
        strokePart.strokeColor = ((UIColor *)_colors[i]).CGColor;
        strokePart.strokeStart = [_segmentsStart[i] floatValue];
        strokePart.strokeEnd = [_segmentsEnd[i] floatValue];

        [_circle addSublayer: strokePart];

        // Configure animation
        CAKeyframeAnimation* drawAnimation = [CAKeyframeAnimation animationWithKeyPath: @"strokeEnd"];
        drawAnimation.duration            = 4.0;

        // Animate from no part of the stroke being drawn to the entire stroke being drawn
        NSArray* times = @[ @(0.0),
                            @(strokePart.strokeStart),
                            @(strokePart.strokeEnd),
                            @(1.0) ];
        NSArray* values = @[ @(strokePart.strokeStart),
                             @(strokePart.strokeStart),
                             @(strokePart.strokeEnd),
                             @(strokePart.strokeEnd) ];

        drawAnimation.keyTimes = times;
        drawAnimation.values = values;
        drawAnimation.removedOnCompletion = NO;
        drawAnimation.fillMode = kCAFillModeForwards;

        // Experiment with timing to get the appearence to look the way you want
        drawAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];


        [strokePart addAnimation: drawAnimation forKey: @"drawCircleAnimation"];
    }
    [CATransaction commit];
}

- (void)_initCircle {
    [_circle removeFromSuperlayer];
    _circle = [CAShapeLayer layer];
    _radius = 100;

    // Make a circular shape
    _circle.path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(0, 0, 2.0 * _radius, 2.0 * _radius) cornerRadius:_radius].CGPath;

    // Center the shape in self.view
    _circle.position = CGPointMake(CGRectGetMidX(self.view.frame) - _radius,
                                   CGRectGetMidY(self.view.frame) - _radius);

    _circle.fillColor = [UIColor clearColor].CGColor;
    _circle.lineWidth = 5;

    // Add to parent layer
    [self.view.layer addSublayer:_circle];
}

-（无效）\u drawStrokeOnCircle{
[self_initCircle]；
[交易开始]；
对于（整数i=0；i<4；i++）
{
CAShapeLayer*strokePart=[[CAShapeLayer alloc]init]；
strokePart.fillColor=[[UIColor clearColor]CGColor]；
strokePart.frame=\u circle.bounds；
strokePart.path=_circle.path；
strokePart.lineCap=_circle.lineCap；
strokePart.lineWidth=_circle.lineWidth；
//配置圆的外观
strokePart.strokeColor=（（UIColor*）_colors[i]）.CGColor；
strokePart.strokeStart=[[u段开始[i]浮点值]；
strokePart.strokeEnd=[[u段发送[i]浮点值]；
[_circleaddsublayer:strokePart]；
//配置动画
CAKeyframeAnimation*drawAnimation=[CAKeyframeAnimation animationWithKeyPath:@“strokeEnd”]；
drawAnimation.duration=4.0；
//从正在绘制的笔划的任何部分到正在绘制的整个笔划设置动画
NSArray*时间=@[@（0.0），
@（strokePart.strokeStart），
@（strokePart.strokeEnd），
@(1.0) ];
NSArray*值=@[@（strokePart.strokeStart），
@（strokePart.strokeStart），
@（strokePart.strokeEnd），
@（strokePart.strokeEnd）]；
drawAnimation.keyTimes=次；
drawAnimation.values=值；
drawAnimation.removedOnCompletion=否；
drawAnimation.fillMode=kCAFillModeForwards；
//尝试计时，让外观看起来像你想要的样子
drawAnimation.timingFunction=[CamediaTimingFunctionWithName:KCAMediaTimingFunctionAsein]；
[strokePart addAnimation:drawAnimation-forKey:@“drawCircleAnimation”]；
}
[CATransaction-commit]；
}
-（无效）{
[_从超级层移除圆圈]；
_圆圈=[CAShapeLayer layer]；
_半径=100；
//做成圆形
_circle.path=[UIBezierPath bezierPathWithRoundedRect:CGRectMake（0,0,2.0*\u半径，2.0*\u半径）cornerRadius:\u半径].CGPath；
//在self.view中将形状居中
_circle.position=CGPointMake（CGRectGetMidX（self.view.frame）——\u半径，
CGRectGetMidY（self.view.frame）——\u半径）；
_circle.fillColor=[UIColor clearColor].CGColor；
_圆形。线宽=5；
//添加到父层
[self.view.layer addSublayer:_circle]；
}

使用“KCAFILLMODEATH”对我有效，这两个语句都是必需的：

//to keep it after finished
animation.removedOnCompletion = false;
animation.fillMode = kCAFillModeBoth;

---

SWIFT 4，代码11:

let strokeIt = CABasicAnimation(keyPath: "strokeEnd")
let timeLeftShapeLayer = CAShapeLayer()

在您的

视图中加载

  override func viewDidLoad() {
    super.viewDidLoad()
    drawTimeLeftShape()
    strokeIt.fillMode = CAMediaTimingFillMode.forwards
    strokeIt.isRemovedOnCompletion = false
    strokeIt.fromValue = 0
    strokeIt.toValue = 1
    strokeIt.duration = 2
    timeLeftShapeLayer.add(strokeIt, forKey: nil)
  }

并通过
UIBezierPath
create函数绘制圆：

func drawTimeLeftShape() {
        timeLeftShapeLayer.path = UIBezierPath(
            arcCenter: CGPoint(x: myView.frame.midX , y: myView.frame.midY),
            radius: myView.frame.width / 2,
            startAngle: -90.degreesToRadians,
            endAngle: 270.degreesToRadians,
            clockwise: true
        ).cgPath
        timeLeftShapeLayer.strokeColor = UIColor.red.cgColor
        timeLeftShapeLayer.fillColor = UIColor.clear.cgColor
        timeLeftShapeLayer.lineWidth = 1
        timeLeftShapeLayer.strokeEnd = 0.0
        view.layer.addSublayer(timeLeftShapeLayer)
    }

对不起，我把你的问题搞错了。这两行代码在动画完成后保持持久性，这是您需要的。但如果我没弄错的话，你还想画一幅多色的画？然后你需要有多个图层，每个图层都有一个不同颜色的笔划段。我需要更多的层次。我已经发布了我的解决方案：）谢谢你的帮助，顺便说一句。添加了fillmode，removedOnCompletion不再需要了。