如果相同，如何将数据传递给之前的视图控制器class Swift

Question

我有一个 table 视图控制器，当我单击 navigationBarItem 中的按钮时，我会打开相同的视图控制器，但设置略有不同，具体取决于标志。通过关闭这个视图控制器，我想将值传递给前一个视图控制器并用新数据重新加载它的数据，我该怎么做？委派在这里无济于事，因为它是相同的 class.

class LibraryViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
...
var isContentFromPlaylist: Bool = false
...
//I open the same VC
@IBAction func addTracksButtonPressed(_ sender: Any) {
        let storyboard = UIStoryboard(name: "LibraryViewController", bundle: nil)
        let vc = storyboard.instantiateViewController(identifier: "Library") as! LibraryViewController
        ...
        navigationController?.showDetailViewController(vc, sender: nil)
    }
...
 @objc private func doneButtonPressed() {
        ...
        //Here I want to change value isContentFromPlaylist to true in previous VC when this VC will close

        dismiss(animated: true, completion: nil)
    }
}

Answer 1

您可以使用这种方法。在 class

中添加一个属性

class LibraryViewController {
    //...
    var creator: LibraryViewController?
    //...
}

然后，在控制器实例化后设置属性...

@IBAction func addTracksButtonPressed(_ sender: Any) {
    let storyboard = UIStoryboard(name: "LibraryViewController", bundle: nil)
    let vc = storyboard.instantiateViewController(identifier: "Library") as! LibraryViewController
    //...
    vc.creator = self // Here it is
    //...
    navigationController?.showDetailViewController(vc, sender: nil)
}

并按照您喜欢的方式使用它：

@objc private func doneButtonPressed() {
        ...
        //Here I want to change value isContentFromPlaylist to true in previous VC when this VC will close
        creator?.isContentFromPlaylist = .........
            
        dismiss(animated: true, completion: nil)
    }
}

P.S。要重新加载数据，请使用 UI 线程：

DispatchQueue.main.async{
    creator?.tableView.reloadData()
}

如果相同，如何将数据传递给之前的视图控制器class Swift

How to pass data to the previous view controller if it is the same class Swift

uitableview

uiviewcontroller

swift