图片翻转

UIImage *img=[UIImage imageNamed:@"sina.png"];
                       UIImage * img1 = [UIImage imageWithCGImage:img.CGImage scale:img.scale orientation:UIImageOrientationRightMirrored];
//                        UIImage *closeImg1 = [UIImage imageWithCGImage:closeImg.CGImage scale: closeImg.scale orientation:UIImageOrientationRightMirrored];
                        
                        [btn1 setBackgroundImage:img1 forState:UIControlStateNormal];