backBarButtonItem图像右对齐，想要居中

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的框架内正确对齐：

如何使图像居中，甚至左对齐？

Answer 1

而不是backBarButtonItem，您需要设置leftBarButtonItem

替换

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

通过此

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