QLPreviewController NavigationBar barTintColor

Question

当我self.present() QLPreviewController时，它的NavigationBar失去了颜色，这是用AppDelegate实现的。

    UINavigationBar.appearance().isTranslucent = false
    UINavigationBar.appearance().tintColor = UIColor.white
    UINavigationBar.appearance().barTintColor = Colors.fifth   // Blue color
    UINavigationBar.appearance().titleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.white]
    UINavigationBar.appearance().shadowImage = UIImage()

QLPreviewController实现：

let preview = QLPreviewController()
preview.dataSource = self

func numberOfPreviewItems(in controller: QLPreviewController) -> Int {
    return 1
}

func previewController(_ controller: QLPreviewController, previewItemAt index: Int) -> QLPreviewItem {
    return fileURL! as QLPreviewItem
}

fileprivate func showDocument(fileId: Int) {
    SVProgressHUD.show()
    self.fileService.download(id: fileId) {
        url, error in

        if error == nil {
            self.fileURL = url
            if QLPreviewController.canPreview(self.fileURL! as QLPreviewItem) {
                self.present(self.preview, animated: true, completion: nil)
                SVProgressHUD.dismiss()
            } else {
                SVProgressHUD.showDismissableError(with: "Произошла ошибка во время чтения файла \(url!.lastPathComponent)")
            }
        } else {
            SVProgressHUD.showDismissableError(with: error?.localizedDescription)
        }
    }
}

我尝试过self.show()，它的NavigationBar是OK！我希望将QLPreviewController's NavigationBar颜色设置为与AppDelegate's UINavigationBar相同的设置。如何以编程方式更改此操作？提前感谢！

Answer 1

首先实例化一个UINavigationController和QLPreviewController作为它的根视图控制器。然后，您可以显示导航栏，它将具有在app委托类中设置的属性。

    let preview = QLPreviewController()
    preview.dataSource = self
    preview.currentPreviewItemIndex = 0
    let navBar = UINavigationController(rootViewController: preview)
    let doneButton = UIBarButtonItem(barButtonSystemItem: .done, target: self, action: #selector(self.dismissQLPreviewController))
    preview.navigationItem.leftBarButtonItem = doneButton
    self.present(navBar, animated: true)