UIBezierPath+CAShapeLayer绘制进度环

- (instancetype)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {

        [self masLayoutSubview];
    }
    return self;
}

+ (instancetype)bezierPathWithArcCenter:(CGPoint)center radius:(CGFloat)radius startAngle:(CGFloat)startAngle endAngle:(CGFloat)endAngle clockwise:(BOOL)clockwise;
:(CGPoint)center中心点
:(CGFloat)radius半径
:(CGFloat)startAngle起点
:(CGFloat)endAngle终点
:(BOOL)clockwise是否顺时针

- (void)masLayoutSubview{
    
    bottomPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(self.frame.size.width/2.0, self.frame.size.height/2.0) radius:self.frame.size.width/2.0 - 10 startAngle:- M_PI_2 endAngle:-M_PI_2 + M_PI * 2 clockwise:YES];

    CAShapeLayer *bottomLayer = [CAShapeLayer layer];
    bottomLayer.frame = self.bounds;
    bottomLayer.path = bottomPath.CGPath;
    bottomLayer.lineWidth = lineWidth;
    bottomLayer.strokeColor = [UIColor grayColor].CGColor;
    bottomLayer.fillColor = nil;
    [self.layer addSublayer:bottomLayer];

    
    layer = [CAShapeLayer layer];
    layer.frame = self.bounds;
    layer.lineWidth = lineWidth;
    layer.fillColor = nil;
    layer.lineCap = kCALineCapRound;
    self.layer.contentsScale = [[UIScreen mainScreen]scale];
    [self.layer addSublayer:layer];
       
    
}

对外提供设置进度接口：(不用多次addsubLayer,直接修改CAShapeLayer的path路径就可以了)
CABasicAnimation 看情况是否加

- (void)setProgress:(CGFloat)value{
    
    path = [UIBezierPath bezierPathWithArcCenter:CGPointMake(self.frame.size.width/2.0, self.frame.size.height/2.0)  radius:self.frame.size.width/2.0 - 10
                                                    startAngle:3*M_PI_2 endAngle:3*M_PI_2+(2*M_PI*value) clockwise:YES];

    layer.path = path.CGPath;
    

    
//    CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];
//    animation.fromValue = @(0.0);
//    animation.toValue = @(1.0);
//    animation.duration = 1.f;
//    [layer addAnimation:animation forKey:nil];
    

}

效果如下：

picture.gif

难点：
定义圆环的起点为3/2π 也就是3*M_PI_2 ，计算终点的公式为3*M_PI_2+(2*M_PI*value)

120336-7f77dcb0cc28e0ef.png