- (void)imageBg
{
    UIImage *oldImage = [UIImage imageNamed:@"me"];
    
    UIGraphicsBeginImageContextWithOptions(self.view.frame.size, NO, 0.0);
    [oldImage drawInRect:self.view.bounds];
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    self.view.backgroundColor = [UIColor colorWithPatternImage:newImage];
}

ios 给一个控制器的view设置背景图片