截取方法:跳过状态栏

时间:2012-08-03 00:14:42

标签: ios ios4 screenshot ios5

我从Apple的网站上获得了这个截图方法:

- (UIImage*)screenshot 
{
    // Create a graphics context with the target size
    // On iOS 4 and later, use UIGraphicsBeginImageContextWithOptions to take the scale into consideration
    // On iOS prior to 4, fall back to use UIGraphicsBeginImageContext
    CGSize imageSize = [[UIScreen mainScreen] bounds].size;
    if (NULL != UIGraphicsBeginImageContextWithOptions)
        UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0);
    else
        UIGraphicsBeginImageContext(imageSize);

    CGContextRef context = UIGraphicsGetCurrentContext();

    // Iterate over every window from back to front
    for (UIWindow *window in [[UIApplication sharedApplication] windows]) 
    {
        if (![window respondsToSelector:@selector(screen)] || [window screen] == [UIScreen mainScreen])
        {
            // -renderInContext: renders in the coordinate space of the layer,
            // so we must first apply the layer's geometry to the graphics context
            CGContextSaveGState(context);
            // Center the context around the window's anchor point
            CGContextTranslateCTM(context, [window center].x, [window center].y);
            // Apply the window's transform about the anchor point
            CGContextConcatCTM(context, [window transform]);
            // Offset by the portion of the bounds left of and above the anchor point
            CGContextTranslateCTM(context,
                                  -[window bounds].size.width * [[window layer] anchorPoint].x,
                                  -[window bounds].size.height * [[window layer] anchorPoint].y);

            // Render the layer hierarchy to the current context
            [[window layer] renderInContext:context];

            // Restore the context
            CGContextRestoreGState(context);
        }
    }

    // Retrieve the screenshot image
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return image;
}

它就像一个魅力,但我有一个小问题:我不希望状态栏在我的截图中显示应用程序。我应该修改什么?老实说,我不知道我应该在这里修改什么,因为我从来没有过多地使用过CG框架。我正在考虑将20(状态栏高度)从一个得到一个" y"财产,但我不想打破这种方法。那么除了状态栏之外,我应该修改什么来截取所有内容?我再次道歉,如果这是一个真正的愚蠢问题,但我真的不知道我会做什么,我会尝试自己修改它。

1 个答案:

答案 0 :(得分:4)

我只是想通了。实际上,我只是从“y”属性中减去了20:

所以不要这样:

CGContextTranslateCTM(context, [window center].x, [window center].y);

我这样做了:

CGContextTranslateCTM(context, [window center].x, [window center].y - 20);

这可能是一种更好的方法,但这个方法很适合我。