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在视图中画线。而且最好不用drawRect，需要保持当前画线的状态，下面是我的代码，没实现： - (void)drawPathWithPoints:(int)xAxis andYaxis:(int)yAxis { CGSize screenSize = drawingImgView.frame.size; UIGraphicsBeginImageContext(drawingImgView.frame.size); CGContextRef currentContext = UIGraphicsGetCurrentContext(); [drawingImgView.image drawInRect:CGRectMake(0, 0, screenSize.width, screenSize.height)]; CGContextSetLineCap(currentContext, kCGLineCapRound); CGContextSetLineWidth(currentContext, 9.0); CGContextSetRGBStrokeColor(currentContext, 0, 0, 1, 1); CGContextBeginPath(currentContext); CGMutablePathRef pointPath = CGPathCreateMutable(); CGContextMoveToPoint(currentContext,xAxis,yAxis); CAKeyframeAnimation *pathAnimation = [CAKeyframeAnimation animationWithKeyPath:@"position"]; pathAnimation.duration = 3.0; pathAnimation.delegate = self; pathAnimation.calculationMode = kCAAnimationPaced; pathAnimation.fillMode = kCAFillModeForwards; pathAnimation.removedOnCompletion = NO; CGPathMoveToPoint(pointPath, NULL, xAxis, yAxis); CGContextAddLineToPoint(currentContext, xAxis, yAxis); CGPathAddLineToPoint(pointPath, NULL, xAxis, yAxis); pathAnimation.path = pointPath; myLayer = [[CAShapeLayer alloc] init]; myLayer.strokeColor = [[UIColor greenColor] CGColor]; myLayer.lineWidth = 11.0; myLayer.fillColor = nil; myLayer.lineJoin = kCALineJoinBevel; myLayer.path = pointPath; [drawingImgView.layer addSublayer:myLayer]; CGPathRelease(pointPath); }

iOS 视+ 上拍摄ar动画的那个效果如何实现？_course

打开 视+， 中间按钮打开相机。画面会有个效果，以屏幕中间为中心向四周间断的扩散。扩散到的地方，会用白线显示轮廓。这应该是滤镜。谁知道如何做的？提供个思路。谢谢。

在动画播放期间让按钮可以使用_course

在应用中的CAKeyframeAnimation，代码如下： -(IBAction)start:(id)sender { UIBezierPath *path = [UIBezierPath bezierPath]; [path moveToPoint:CGPointMake(600, 150)]; [path addLineToPoint:CGPointMake(600, 300)]; [path addLineToPoint:CGPointMake(450, 300)]; [path addLineToPoint:CGPointMake(450, 150)]; [path addLineToPoint:CGPointMake(600, 150)]; CAKeyframeAnimation *move = [CAKeyframeAnimation animationWithKeyPath:@"position"]; move.path = path.CGPath; move.duration = 6.0f; move.repeatCount = 100; [testButton.layer addAnimation:move forKey:@"move"]; 怎么让动画进行的时候按钮也能用？试了好几种方法也没实现。 谢谢指教

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CAKeyframeAnimation 失效的疑问_course

UIButton * btn = initWithFrame:CGRectMake(100, 100, 50, 50)]; btn.backgroundColor = ; ; CGRect bound

多个UIBezierPath拼接起来的运动轨迹，在我执行动画的时候，整个的动画效果会出现卡顿，_course

执行动画的代码： CAKeyframeAnimation *keyframeAnimation=[CAKeyframeAnimation animationWithKeyPath:@"position"]; keyframeAnimation.path = dr.aPath.CGPath; keyframeAnimation.repeatCount=1; keyframeAnimation.removedOnCompletion = NO; keyframeAnimation.fillMode = kCAFillModeForwards; keyframeAnimation.duration = 4.0f; keyframeAnimation.timingFunction=[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut]; keyframeAnimation.delegate=self; [imageView.layer addAnimation:keyframeAnimation forKey:nil]; ``` 画的动画路径: - (void)drawRect:(CGRect)rect { UIColor *color = [UIColor redColor]; [color set]; _aPath = [UIBezierPath bezierPath]; [_aPath addArcWithCenter:CGPointMake(self.center.x, self.center.y-50) radius:50 startAngle:M_PI_2 endAngle:M_PI*2.f*3/4 clockwise:YES]; [_aPath addArcWithCenter:CGPointMake(self.center.x, self.center.y) radius:100 startAngle:-M_PI_2 endAngle:M_PI*2.f*3/4 clockwise:YES];// 逆时针 [_aPath addArcWithCenter:CGPointMake(self.center.x, self.center.y) radius:100 startAngle:-M_PI_2 endAngle:M_PI*2.f*3/4/3 clockwise:YES];// 逆时针 [_aPath addArcWithCenter:CGPointMake(self.center.x, self.center.y+50) radius:50 startAngle:M_PI_2 endAngle:M_PI*2.f*3/4 clockwise:YES]; _aPath.lineWidth = 5.0; _aPath.lineCapStyle = kCGLineCapRound; //线条拐角 _aPath.lineJoinStyle = kCGLineCapRound; //终点处理 [_aPath stroke]; } ```

CAKeyframeAnimation动画_course

CAKeyframeAnimation动画结束有没有回调方法， 我看了一下它里面的头文件，没找到，