UIBezierPath与CAShapeLayer结合画扇形

/*让半径等于期望半径的一半 lineWidth等于期望半径 就可以画圆*/

可以看出layer的走势是从圆边的中间一半在圆外 一半在圆内 因此让半径等于期望半径的一半 lineWidth等于期望半径

- (void)viewDidLoad {

    [super viewDidLoad];

    for (NSInteger i=; i<; i++) {

        [self itemViewWithOne:*i*M_PI/180.0 two:*(i+)*M_PI/180.0];

    }

}

- (UIView *)bgView

{

    if (!_bgView) {

        _bgView = [[UIView alloc] init];

        _bgView.backgroundColor = [UIColor grayColor];

        _bgView.bounds = CGRectMake(, , , );

        _bgView.center = self.view.center;

        [self.view addSubview:_bgView];

    }

    return _bgView;

}

- (void)itemViewWithOne:(CGFloat)starAngle two:(CGFloat)endAngle

{

    /*让半径等于期望半径的一半  lineWidth等于期望半径 就可以画圆*/

    CAShapeLayer *layer = [CAShapeLayer layer];

    UIBezierPath *bezierPath = [UIBezierPath bezierPath];

    [bezierPath addArcWithCenter:CGPointMake(,) radius: startAngle:starAngle endAngle:endAngle clockwise:YES];

    layer.path = bezierPath.CGPath;

//    bezierPath.lineCapStyle = kCGLineCapButt;

    layer.lineWidth = ;

    UIColor *color = [UIColor colorWithRed:arc4random()%/255.0 green:arc4random()%/255.0 blue:arc4random()%/255.0 alpha:];

//    UIColor *color1 = [UIColor colorWithRed:arc4random()%256/255.0 green:arc4random()%256/255.0 blue:arc4random()%256/255.0 alpha:1];

    layer.strokeColor = color.CGColor;

    // 最好 为clearColor 设置颜色是方便观察

    layer.fillColor = [UIColor yellowColor].CGColor;

    //默认

    layer.lineCap = kCALineCapButt;

    [self.bgView.layer addSublayer:layer];

    CABasicAnimation *basic = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];

    basic.duration = 1.1;

    basic.fromValue = @(0.1f);

    basic.toValue = @(1.0f);

    [layer addAnimation:basic forKey:@"basic"];

}

结果如下：