Question

嗨！我想绘制UIView的圆角。 只有一个，其他人无法更改。

Answer 1

从iOS 3.2开始，您可以使用UIBezierPath的功能创建一个开箱即用的圆角矩形（其中只有您指定的角是圆角的）。然后，您可以将其用作CAShapeLayer的路径，并将其用作视图图层的蒙版：

// Create the path (with only the top-left corner rounded)
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:imageView.bounds 
                                               byRoundingCorners:UIRectCornerTopLeft
                                                     cornerRadii:CGSizeMake(10.0, 10.0)];

// Create the shape layer and set its path
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = imageView.bounds;
maskLayer.path = maskPath.CGPath;

// Set the newly created shape layer as the mask for the image view's layer
imageView.layer.mask = maskLayer;

就是这样 - 没有搞乱在Core Graphics中手动定义形状，没有在Photoshop中创建遮罩图像。该层甚至不需要无效。应用圆角或更改为新角非常简单，只需定义新的UIBezierPath并使用其CGPath作为遮罩层的路径即可。 corners方法的bezierPathWithRoundedRect:byRoundingCorners:cornerRadii:参数是一个位掩码，因此可以通过对它们进行OR运算来舍入多个角。

注意 - 与CALayer renderInContext方法结合使用时，不会渲染图层蒙版。如果您需要使用此功能，请尝试使用以下内容进行四舍五入：Just two rounded corners?。

Answer 2

我做了一个StuDev答案的方法：

+ (CAShapeLayer *) roundedCornerOnImage: (UIImageView *)imageView onCorner: (UIRectCorner)rectCorner
{
    UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:imageView.bounds 
                                                   byRoundingCorners:rectCorner
                                                         cornerRadii:CGSizeMake(10.0, 10.0)];

    CAShapeLayer *maskLayer = [CAShapeLayer layer];
    maskLayer.frame = imageView.bounds;
    maskLayer.path = maskPath.CGPath;

    return maskLayer;
}

UITableViewCell中imageview的使用示例：

if (indexPath.row == 0)
    cell.imageView.layer.mask = [Helper roundedCornerOnImage:cell.imageView onCorner:UIRectCornerTopLeft];
else if (indexPath.row == self.arrayPeople.count - 1)
    cell.imageView.layer.mask = [Helper roundedCornerOnImage:cell.imageView onCorner:UIRectCornerBottomLeft];

感谢StuDev提供了一个很好的解决方案！

Answer 3

+ (CAShapeLayer *) roundedCornerOnImage: (UIImageView *)imageView onCorner: (UIRectCorner)rectCorner
{
    UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:imageView.bounds 
                                                   byRoundingCorners:rectCorner
                                                         cornerRadii:CGSizeMake(10.0, 10.0)];

    CAShapeLayer *maskLayer = [CAShapeLayer layer];
    maskLayer.frame = imageView.bounds;
    maskLayer.path = maskPath.CGPath;
    imageView.layer.mask=maskLayer
    return maskLayer;
}


if (indexPath.row == 0)
    [Helper roundedCornerOnImage:cell.imageView onCorner:UIRectCornerTopLeft];
else if (indexPath.row == self.arrayPeople.count - 1)
  [Helper roundedCornerOnImage:cell.imageView onCorner:UIRectCornerBottomLeft];

上面的更新答案，你不需要返回并管理它。它可以在该功能中完成。

Answer 4

我做了一个函数，在做了一些小型R＆amp; D之后制作自定义角半径，如下所示：

+(void)setConerRadiusForTopLeft:(BOOL)isForTopLeft ForTopRight:(BOOL)isForTopRight ForBottomLeft:(BOOL)isForBottomLeft  ForBottomRight:(BOOL)isForBottomRight withCornerRadius:(float)cornerRadius forView:(UIView *)view
{

    UIRectCorner corners = (isForTopLeft ? UIRectCornerTopLeft : 0) |
                          (isForTopRight ? UIRectCornerTopRight : 0) |
                          (isForBottomLeft ? UIRectCornerBottomLeft : 0) |
                          (isForBottomRight ? UIRectCornerBottomRight : 0);

    UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:view.bounds
                                               byRoundingCorners:corners
                                                     cornerRadii:CGSizeMake(cornerRadius, cornerRadius)];

    CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
    maskLayer.frame = view.bounds;
    maskLayer.path = maskPath.CGPath;
    view.layer.mask = maskLayer;
}

如何绘制我的UIView的单个圆角。

4 个答案: