ios - 为圆角的UIImage添加边框

Question

我有一个矩形的UIImage，我想使它变圆并带有边框，我在SO上发现了一个使它变圆并起作用的问题，这是代码:

- (UIImage*) roundCorneredImage: (UIImage*) orig radius:(CGFloat) r {
    UIGraphicsBeginImageContextWithOptions(orig.size, NO, 0);
    [[UIBezierPath bezierPathWithRoundedRect:(CGRect){CGPointZero, orig.size}
                                cornerRadius:r] addClip];
    [orig drawInRect:(CGRect){CGPointZero, orig.size}];
    UIImage* result = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return result;
}

但是知道我在尝试如何在图像周围形成白色边框，但没有结果，我该怎么办？

Answer 1

尝试这个 :

- (UIImage*) roundCorneredImage: (UIImage*) orig radius:(CGFloat) r {
    UIGraphicsBeginImageContextWithOptions(orig.size, NO, 0);
    UIBezierPath *bezierPath =[UIBezierPath bezierPathWithRoundedRect:(CGRect){CGPointZero, orig.size}
                                                         cornerRadius:r];
    [bezierPath setLineWidth:6.0];
    [[UIColor whiteColor] setStroke];
    [bezierPath stroke];
    [bezierPath addClip];

    [orig drawInRect:(CGRect){CGPointZero, orig.size}];
    UIImage* result = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return result;
}