backBarButtonItem 图像右对齐，希望居中

Question

我正在尝试将 backBarButtonItem 设置为具有自定义图像：

self.navigationItem.backBarButtonItem = UIBarButtonItem(image: UIImage(named: "Back"), style: .plain, target: self, action: #selector(self.navigationController?.popViewController(animated:)))
self.navigationItem.backBarButtonItem?.tintColor = UIColor.red

我注意到，当我为 navigationController 设置 backBarButtonItem 时，图像在 backBarButtonItem 的框架内右对齐：

如何使图像居中，甚至左对齐？

Answer 1

您需要设置 leftBarButtonItem

而不是 backBarButtonItem

替换这个

self.navigationItem.backBarButtonItem = UIBarButtonItem(image: UIImage(named: "Back"), style: .plain, target: self, action: #selector(self.navigationController?.popViewController(animated:)))
self.navigationItem.backBarButtonItem?.tintColor = UIColor.red

由此

self.navigationItem.leftBarButtonItem = UIBarButtonItem(image: UIImage(named: "Back"), style: .plain, target: self, action: #selector(self.navigationController?.popViewController(animated:)))
self.navigationItem.leftBarButtonItem?.tintColor = UIColor.red