通過“ UINavigationController”子類正確設置“ Root ViewController”

Question

我正在嘗試通過代碼動態地通過其子類更改UINavigationController的Root 。

基本上，我的Storyboard如下所示：

#MARK：應用故事板

如您所見，我將CustomNavigationController設置為Initial View Controller選項（通過Storyboard ）。

我如何通過CustomNavigationController類設置將在我運行應用程序時顯示的根ViewController ？

#MARK：“ CustomNavigationController”類

class CustomNavigationController: UINavigationController {

  // What method should i use?

}

Answer 1

必須為右側的兩個視圖控制器提供情節提要板標識符（在“身份檢查器”選項卡上）。

然后在您的自定義NavVC中，在根目錄下構建所需的視圖控制器，並通過使其成為導航堆棧（數組）中唯一的視圖控制器使其成為根目錄...

- (void)viewWillAppear:animated {
    [super viewWillAppear:animated];
    UIStoryboard *storyboard = [self storyboard];
    UIViewController *vc = [storyboard instantiateViewControllerWithIdentifier:@"one of the ids you set up"];
    self.viewControllers = @[ vc ];
}

迅速（非常確定）...

override func viewWillAppear() {
    super.viewWillAppear()
    let storyboard = self.storyboard
    let vc = storyboard.instantiateViewController(withIdentifier: "one of the ids you set up")
    self.viewControllers = [ vc ] 
}