ios編程：iPhone How-to:給UIView拍照

基本原理就是主要將UIView的layer描繪到圖形上下文。UIView全域拍照和局域拍照的代碼如下：

1 UIView全域拍照

- (UIImage *) screenImage:(UIView *)view {    UIImage *screenImage;    UIGraphicsBeginImageContext(view.frame.size);    [view.layer renderInContext:UIGraphicsGetCurrentContext()];    screenImage = UIGraphicsGetImageFromCurrentImageContext();    UIGraphicsEndImageContext();    return screenImage;}

2 UIView局域拍照

- (UIImage *) screenImage:(UIView *)view rect:(CGRect)rect {    CGPoint pt = rect.origin;    UIImage *screenImage;    UIGraphicsBeginImageContext(rect.size);    CGContextRef context = UIGraphicsGetCurrentContext();    CGContextConcatCTM(context,    CGAffineTransformMakeTranslation(-(int)pt.x, -(int)pt.y));    [view.layer renderInContext:context];    screenImage = UIGraphicsGetImageFromCurrentImageContext();    UIGraphicsEndImageContext();    return screenImage;}