设置UIImagePickerController里面的返回按钮的样式图片

重写UIImagePickerController来实现 在viewDidLoad中设置

 var image = R.image.left

        image = image?.imageWithRenderingMode(UIImageRenderingMode.Automatic)

        

        let insets = UIEdgeInsetsMake(6, -20, -6, 20)

        let backArrowImage = image?.imageWithAlignmentRectInsets(insets)

        self.navigationBar.backIndicatorImage = backArrowImage

        self.navigationBar.backIndicatorTransitionMaskImage = backArrowImage

        重写如下方法：

        override func pushViewController(viewController: UIViewController, animated: Bool) {

        if viewControllers.count >= 0 {

            let bar = UIBarButtonItem(image: R.image.left, style: UIBarButtonItemStyle.Done, target: self, action: #selector(self.goBack))

            viewController.navigationItem.leftBarButtonItem = bar

        }

        super.pushViewController(viewController, animated: animated)

    }

    @objc private func goBack() {

        self.popViewControllerAnimated(true)

    }

    UIImagePickerController会有一个问题 ，右滑 滑动到一半 取消滑动 leftBarButtonItem的显示会取消 变成backIndicatorTransitionMaskImage的样式 导致看到的效果是图标左边 向下移动了一点 这样很不好  但是又没找到相关的解决方法 请各位大神支招？