一个扇形的动画效果

-(void)addarcanimation
{
    CAShapeLayer *linelayer=[CAShapeLayer layer];
    linelayer.strokeColor=[[UIColor colorWithRed:0.400 green:1.000 blue:1.000 alpha:1.000] CGColor];
    linelayer.fillColor=nil;//不能动态填充，你可以试试把设置个颜色，把linewidth设置小一些 看有什么效果。
    linelayer.lineWidth=40.0f;//线条宽度必须设高一点，设低了就是空心的
    linelayer.lineCap=kCALineCapButt;
    [self.view.layer addSublayer:linelayer];
//把layer插入你需要绘图的layer
    
    float x=self.view.bounds.size.width/2;
    float y=self.totaltimelable.frame.origin.y+self.totaltimelable.frame.size.height+(self.xuanzeLable.frame.origin.y-(self.totaltimelable.frame.origin.y+self.totaltimelable.bounds.size.height))/2;
    
    float radius=(self.xuanzeLable.frame.origin.y-(self.totaltimelable.frame.origin.y+self.totaltimelable.bounds.size.height))/2/2-5;
    
    UIBezierPath *path=[UIBezierPath bezierPathWithArcCenter:CGPointMake(x, y) radius:radius startAngle:0 endAngle:M_PI*2*[self totalworktimeproportionoftotaltime] clockwise:YES];
    
    linelayer.path=path.CGPath;//把layer的path设为动画里尼创建的path 必须是cgpath类型

    
    CABasicAnimation *animation=[CABasicAnimation animationWithKeyPath:@"strokeEnd"];
    
    animation.duration=1.0f;
    
    animation.timingFunction=[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut];
    
    animation.fromValue=[NSNumber numberWithFloat:0.0f];
    
    animation.toValue=[NSNumber numberWithFloat:1.0f];
    
    animation.autoreverses=NO;
    
    animation.fillMode=kCAFillModeForwards;
    
    animation.repeatCount=1;
    
    [linelayer addAnimation:animation forKey:@"strokeEndAnimation"];
    
    linelayer.strokeEnd=1.0f;
    //一定要把strokeEnd是什么搞清楚，它代表了layer的绘制程度，从0到1，0的话就是什么都不绘制，1的话就是完全绘制。
    
}