使用UIBezierPath动画绘制弧

Question

我用以下方法画了一个圆弧:

- (void)drawRect:(CGRect)rect {
    UIBezierPath *stripePath = [UIBezierPath bezierPath];
    [arcColor set];
    [stripePath addArcWithCenter:center radius:radius startAngle:startAngle endAngle:endAngle clockwise:clockwise];
    stripePath.lineWidth = arcWidth;
    stripePath.lineCapStyle = kCGLineCapRound;
    stripePath.lineJoinStyle = kCGLineCapRound;
    [stripePath stroke];
}

现在我想以角度为这个弧设置动画.

我正在尝试使用类似的东西:

angle = startAngle;
[UIView animateWithDuration:1
                      delay:0
                    options:UIViewAnimationOptionCurveEaseInOut
                 animations:^{
                     angle = endAngle;
                     [stripePath addArcWithCenter:center radius:radius startAngle:startAngle endAngle:angle clockwise:clockwise];
                     [stripePath stroke];
}];

但是,屏幕上没有显示动画.如何使用角度作为变化变量来设置弧的动画？谢谢.

Answer 1

以下代码实现了我的目标:

UIBezierPath *stripePath = [UIBezierPath bezierPath];
[arcColor set];
stripePath.lineWidth = arcWidth;
stripePath.lineCapStyle = kCGLineCapRound;
stripePath.lineJoinStyle = kCGLineCapRound;
[stripePath addArcWithCenter:center radius:radius startAngle:startAngle endAngle:endAngle clockwise:clockwise];

[_stripeLayer setPath:stripePath.CGPath];
[_stripeLayer setStrokeColor:arcColor.CGColor];
[_stripeLayer setFillColor:[UIColor clearColor].CGColor];
[_stripeLayer setLineWidth:arcWidth];
[_stripeLayer setStrokeStart:0.0];
[_stripeLayer setStrokeEnd:1.0];
[_stripeLayer setLineCap:kCALineCapRound];
[_stripeLayer setLineJoin:kCALineCapRound];

if ([_stripeLayer superlayer]) {
    [_stripeLayer removeAllAnimations];
    [_stripeLayer removeFromSuperlayer];

}
[self.layer addSublayer:_stripeLayer];

CABasicAnimation *animateStrokEnd = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];
animateStrokEnd.duration = 1;
animateStrokEnd.fromValue = [NSNumber numberWithFloat:0.0];
animateStrokEnd.toValue = [NSNumber numberWithFloat:1.0];
[_stripeLayer addAnimation:animateStrokEnd forKey:nil];

Answer 2

MHRadialProgressView可能 会帮助您按特定角度制作弧线动画。