调整 UIImageView 剪辑子图层的大小

Question

我有一个自定义UIImageView，它插入了一个子图层，如下所示：

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        small_ = frame;
        float newX = self.center.x - ((self.frame.size.width*SELECTED_SCALE_VALUE)*0.5);
        float newY = self.center.y - ((self.frame.size.height*SELECTED_SCALE_VALUE)*0.5);
        big_ = CGRectMake(newX, newY, self.frame.size.width*SELECTED_SCALE_VALUE, self.frame.size.height*SELECTED_SCALE_VALUE);
        [self setupSubviews];
    }
    return self;
}
- (void)setupSubviews
{
    shadowImage_ = [[UIImage imageNamed:@"gallery_shadow_frame"] resizableImageWithCapInsets:UIEdgeInsetsMake(20, 20, 20, 20)];
    shadowImageView_ = [[UIImageView alloc] initWithFrame:[self shadowFrame]];
    shadowImageView_.image = shadowImage_;
    shadowImageView_.backgroundColor = [UIColor blueColor];
    [self.layer insertSublayer:[shadowImageView_ layer] atIndex:0];
}

当我稍后调整UIImageView帧的大小时，它会剪切子图层：

- (void)makeBig
{
    self.frame = big_;
    // shadowImageView_.frame = [self shadowFrame];
}
- (void)makeSmall
{
    self.frame = small_;
    // shadowImageView_.frame = [self shadowFrame];
}

为了给出一个完整的画面，还有这个：

- (CGRect)shadowFrame
{
    int x = -X_BORDER;
    int y = -Y_BORDER;
    int width = self.frame.size.width + X_BORDER * 2;
    int height = self.frame.size.height + Y_BORDER * 2;
    return CGRectMake(x, y, width, height);
}

如何调整UIImageView的大小，但防止它剪裁它的shadowImageView_ sublayer？

Answer 1

你试过吗

self.layer.masksToBounds = NO;

？