手动编程 NSLayoutConstraint

项目中有个admob view是后期加上的 没写在storyboard里  所以new出来后需要手动加上NSLayoutConstraint

加的时候怎么也调不好后来发现是少了一句

[bannerView setTranslatesAutoresizingMaskIntoConstraints: NO];

加上这句程序运行就一切符合自己期待了

    [bannerView setTranslatesAutoresizingMaskIntoConstraints: NO];
    NSLayoutConstraint *centerX = [bannerView.centerXAnchor constraintEqualToAnchor: self.view.centerXAnchor];
    NSLayoutConstraint *bottom = [bannerView.bottomAnchor constraintEqualToAnchor: self.bottomview.topAnchor];
    
   [NSLayoutConstraint activateConstraints: @[centerX, bottom]];