如何在iOS中的循环路径上动画标签？

Question

我被困在动画uiLabel在我看来。

其实我只想在圆形路径上为我的标签/文字制作动画。我在互联网上搜索了很多，但找不到任何好的教程或例子，正在做我的问题。我已经完成了CAShapeLayer（圆圈）从0增加到其最大值......

同样，我希望我的标签/文本从圆形路径中的初始点开始移动，并在完成一个圆后返回到其初始点。

希望我已经相当准确地解释了我的问题......仍然有任何遗漏或无法理解的地方。请问我。

感谢您的期待。

Answer 1

IOMI嗨，我只是谷歌，我发现最好的问题类似像你This

娄它一斤的回答希望它可以帮助你

 CAShapeLayer* circle = [[CAShapeLayer alloc] init]; 
     CGMutablePathRef path = CGPathCreateMutable(); 
     CGRect textRect = CGRectMake(self.view.bounds.size.width/4, (self.view.bounds.size.height-self.view.bounds.size.width/2)/2, self.view.bounds.size.width/2, self.bounds.size.width/2); 
     float midX = CGRectGetMidX(textRect); 
     float midY = CGRectGetMidY(textRect); 
     CGAffineTransform t = CGAffineTransformConcat(
           CGAffineTransformConcat(
            CGAffineTransformMakeTranslation(-midX, -midY), 
            CGAffineTransformMakeRotation(-1.57079633/0.99)), 
           CGAffineTransformMakeTranslation(midX, midY)); 
     CGPathAddEllipseInRect(path, &t, textRect); 
     circle.path = path; 
     circle.frame = self.bounds; 
     circle.fillColor = [UIColor clearColor].CGColor; 
     circle.strokeColor = [UIColor blackColor].CGColor; 
     circle.lineWidth = 60.0f; 
     [self.layer addSublayer:circle]; 

     CABasicAnimation* animation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"]; 
     animation.duration = 15.0f; 
     animation.fromValue = [NSNumber numberWithFloat:0.0f]; 
     animation.toValue = [NSNumber numberWithFloat:1.0f]; 
     animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear]; 
     [circle addAnimation:animation forKey:@"strokeEnd"]; 

     [circle release]; 

     UILabel* label = [[UILabel alloc] init]; 
     label.text = @"Test Text"; 
     label.font = [UIFont systemFontOfSize:20.0f]; 
     label.center = CGPathGetCurrentPoint(path); 
     label.transform = CGAffineTransformMakeRotation(1.57079633); 
     [label sizeToFit]; 
     [self.layer addSublayer:label.layer]; 

     CAKeyframeAnimation* textAnimation = [CAKeyframeAnimation animationWithKeyPath:@"position"]; 
     textAnimation.duration = 15.0f; 
     textAnimation.path = path; 
     textAnimation.rotationMode = kCAAnimationRotateAuto; 
     textAnimation.calculationMode = kCAAnimationCubicPaced; 
     textAnimation.removedOnCompletion = NO; 
     [label.layer addAnimation:textAnimation forKey:@"position"]; 

我只是创建它的屏幕截图是一个演示： -

这里是DEMO LINK

http://www.sendspace.com/file/dq5i1e