ios – 将UIImage安装到屏幕中心

我有一个viewcontroller,其中UI Imageview是子视图. UIImages有不同的尺寸和方向.但我想能够将它们放在屏幕中间.
我试图为UIImageview定义一个框架但是我无法获得CGRectMake的4个参数.

UIImage *backgroundLogoImage = [UIImage imageNamed:@"center_logo.png"];
UIImageView *backgroundLogoImageView = [[UIImageView alloc] init];
backgroundLogoImageView.frame = CGRectMake((self.view.frame.size.width / 2) - (backgroundLogoImage.size.width / 2), (self.view.frame.size.height / 2) - (backgroundLogoImage.size.height / 2), backgroundLogoImage.size.width, backgroundLogoImage.size.height);