截取当前视图

当前视图中所有的子视图进行截取

- (UIImage *)screenImage {

    CGSize size =self.bounds.size;

    UIGraphicsBeginImageContextWithOptions(size,YES,0);

    UIImage *screenImage =nil;

    [selfdrawViewHierarchyInRect:CGRectMake(0,0, size.width, size.height)

               afterScreenUpdates:YES];

    screenImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return screenImage;

}