1

我想绘制一个带有一些圆圈的褪色黑色背景颜色的视图。它看起来应该是圆形部分应该是空心的，我应该能够看到下面的视图。

CALayer 掩蔽对我没有帮助，或者我可能没有以正确的方式应用它们（请参见下面的注释代码）。

下面是我的代码，附件是我现在看到的屏幕截图。

预期：带有空心圆圈的黑色褪色视图。

有什么建议么

#pragma Initializer

- (id)initWithFrame:(CGRect)iFrame andHollowFrames:(NSArray *)iHollowFrames {
    if ((self = [super initWithFrame:iFrame]) != nil) {
        self.hollowFrames = [NSArray arrayWithArray:iHollowFrames];
        //self.layer.backgroundColor = CGColorCreateCopyWithAlpha([UIColor blackColor].CGColor, 0.5);

        CAShapeLayer *circle1 = [self circleAt:CGPointMake(20.0, 20.0) ForRadius:10.0 withColor:[UIColor blackColor].CGColor andDashPattern:NO];
        CAShapeLayer *circle2 = [self circleAt:CGPointMake(120.0, 20.0) ForRadius:10.0 withColor:[UIColor blackColor].CGColor andDashPattern:NO];

        CALayer *myLayer = [CAShapeLayer layer];
        myLayer.frame = self.frame;
        myLayer.backgroundColor = CGColorCreateCopyWithAlpha([UIColor blackColor].CGColor, 0.5);
        [self.layer addSublayer:myLayer];

//        [circle1 setMask:myLayer];
//        [circle2 setMask:myLayer];

        [self.layer addSublayer:circle1];
        [self.layer addSublayer:circle2];
    }
    return self;
}



#pragma Drawing Methods

- (CAShapeLayer *)circleAt:(CGPoint)iPoint ForRadius:(CGFloat)iRadius withColor:(CGColorRef)iColor andDashPattern:(BOOL)isDashPattern {
    CAShapeLayer *aSignalcircle = [CAShapeLayer layer];
    aSignalcircle.path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(iPoint.x, iPoint.y, 2.0 * iRadius, 2.0 * iRadius) cornerRadius:iRadius].CGPath;
    aSignalcircle.position = CGPointMake(0.0 - iRadius, 0.0 - iRadius);
    aSignalcircle.fillColor = [UIColor clearColor].CGColor;
    aSignalcircle.strokeColor = iColor;
    aSignalcircle.lineWidth = kPSSignalStrokeWidth;
    aSignalcircle.backgroundColor = [UIColor clearColor].CGColor;


    if (isDashPattern) {
        aSignalcircle.lineDashPattern = @[@1, @1];
    }

    return aSignalcircle;
}

在此处输入图像描述

4

2 回答 2

2

让它与下面的代码一起工作：

- (void)addShadowView {
    self.hollowFrames = @[[NSValue valueWithCGPoint:CGPointMake(20.0, 20.0)], [NSValue valueWithCGPoint:CGPointMake(120.0, 20.0)]];

    int radius = 15.0;
    UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(0, 0, self.bounds.size.width, self.bounds.size.height) cornerRadius:0];

    for (NSValue *point in self.hollowFrames) {
        UIBezierPath *circlePath = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(point.CGPointValue.x, point.CGPointValue.y, 2.0*radius, 2.0*radius) cornerRadius:radius];
        [path appendPath:circlePath];
    }

    [path setUsesEvenOddFillRule:YES];

    CAShapeLayer *fillLayer = [CAShapeLayer layer];
    fillLayer.path = path.CGPath;
    fillLayer.fillRule = kCAFillRuleEvenOdd;
    fillLayer.fillColor = [UIColor blackColor].CGColor;
    fillLayer.opacity = 0.5;
    [self.layer addSublayer:fillLayer];
}
于 2013-09-20T20:56:14.790 回答
0

当我试图用我的代码做一些事情时，我遇到了类似的问题，我通过用颜色填充它然后使用背景作为我想要的颜色创建一个可视窗口大小的新层来解决这个问题colorClear 然后在那里使用遮罩（哦，稍后发送回全屏）。您的问题是，在渲染图层时，即使在剪切之后背景颜色也会显示出来，而不是通过该级别，因为它是视图堆栈的底部。

于 2013-09-20T19:45:04.827 回答