如何在iPhone中使用相机预览拍摄屏幕截图？

Question

i can take screenshots now but in the place of camera preview, It appears a black display and the camera preview is not been displayed. Any ideas ?

Here my code is :

CGRect screenRect = [[UIScreen mainScreen] bounds];
UIGraphicsBeginImageContext(screenRect.size);
CGContextRef ctx = UIGraphicsGetCurrentContext();
[[UIColor whiteColor] set];
CGContextFillRect(ctx, screenRect);
[self.view.layer renderInContext:ctx];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

return img;

Now I m currently use this code.

Answer 1

Your code seems to be correct doesn't figure out what is going wrong in your code.I suggest you to try out this code.It works for me.

- (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;
}

courtesy:- https://stackoverflow.com/a/8996637/1865424

you can read this thread to know more about Screenshot capture. https://discussions.apple.com/message/8358740?messageID=8358740#8358740?messageID=8358740

Hope this will help you out.