uiview只渲染特定区域xcode(不是通过裁剪)

时间:2013-10-15 14:20:40

标签: ios objective-c uiview render crop

我现在正在尝试渲染uiview。我可以用这样的东西正确地渲染整个uiview。

    [toBeRecorded.layer renderInContext:UIGraphicsGetCurrentContext()];

但是,我想知道只渲染这样的特定区域(不是通过裁剪..但只渲染特定区域)。我该怎么办?

enter image description here

1 个答案:

答案 0 :(得分:6)

这是答案,我写了这个方法,并且完美地运作:

+ (UIImage*) screenShotTheArea:(CGRect)area inView:(UIView*)view{

        if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)])
            UIGraphicsBeginImageContextWithOptions(CGSizeMake(area.size.width, area.size.height), NO, [UIScreen mainScreen].scale);
        else
            UIGraphicsBeginImageContext(view.bounds.size);

        CGContextRef c = UIGraphicsGetCurrentContext();
        CGContextTranslateCTM(c, -area.origin.x, -area.origin.y);
        [view.layer renderInContext:c];
        UIImage* thePrintScreen = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();

        return thePrintScreen;
    }