Question

我可以让segue工作，但是集合/表viewController中的数据都不会传递给细节（我只得到白屏。）

这是collectionViewController（名为MemeCollectionViewController）

import UIKit
import Foundation


class SentMemesCollectionViewController: UICollectionViewController {

    @IBOutlet weak var flowLayout: UICollectionViewFlowLayout!

    var _collectionView = SentMemesCollectionViewController!.self


    //calling memes from array in Delegate
    let appDelegate = UIApplication.shared.delegate as! AppDelegate
    var memes: [Meme] {
        return appDelegate.memes
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        collectionView?.reloadData()

        flowLayoutSettings()

    }
    func flowLayoutSettings() {

        let space: CGFloat = 3.0
        let dimension = (self.view.frame.size.width - (2 * space)) / 3

        flowLayout.minimumInteritemSpacing = space
        flowLayout.minimumLineSpacing = space
        flowLayout.itemSize = CGSize(width: dimension, height: dimension)
    }


    override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
                return memes.count
    }

    override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "MemeCollectionViewCell", for: indexPath) as! MemeCollectionViewCell

        let meme = self.memes[indexPath.item]
        cell.getCellMeme(meme.memedImage)

        return cell
    }

    override func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {

    }

    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "MemeDetailViewController" ,
        let nextScene = segue.destination as? MemeDetailViewController ,
            let cell = collectionView?.dequeueReusableCell(withReuseIdentifier: "MemeCollectionViewCell", for: IndexPath) {
            let selectedMeme = memes[IndexPath]

        }
    }

}

tableViewController，名为MemeTableViewController

    import UIKit

class SentMemesTableViewController: UITableViewController {

    var _tableView: UITableView!
    var memeData: [Meme] = []



    //calling memes from array in Delegate
    let appDelegate = UIApplication.shared.delegate as! AppDelegate
    var memes: [Meme] {
        return appDelegate.memes

    }

    override func viewWillAppear(_ animated: Bool) {
        tableView.reloadData()
    }


    override func viewDidLoad() {
        super.viewDidLoad()

        tableView.isScrollEnabled = true

    }

    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {

        if segue.identifier == "MemeDetailViewController" ,
        let _ = segue.destination as? MemeDetailViewController,
            let indexPath = tableView.indexPathForSelectedRow {
            let selectedMeme = memeData[indexPath.row]
            _ = SentMemeImage(memedImage: selectedMeme.memedImage)
        }
    }


    // MARK: - Table view data source

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

            //navigationController!.pushViewController(MemeDetailViewController, animated: true)

    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        // #warning Incomplete implementation, return the number of rows
        return memes.count
    }

    // Here it is! -----

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let tableViewCell = tableView.dequeueReusableCell(withIdentifier: "sentMemesTableView") as! MemeTableViewCell
        let meme = memes[indexPath.row]

        tableViewCell.tableViewImage.image = meme.memedImage
        tableViewCell.tableViewLabel.text = "\(meme.topText)...\(meme.bottomText)"



        return tableViewCell
    }

    // Override to support conditional editing of the table view.
    override func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
        // Return false if you do not want the specified item to be editable.
        return true
    }

    // Override to support conditional rearranging of the table view.
    override func tableView(_ tableView: UITableView, canMoveRowAt indexPath: IndexPath) -> Bool {
        // Return false if you do not want the item to be re-orderable.
        return false

    }

    func deleteMemesInTableViewCell(_ index: Int) {
        let appDelegate = UIApplication.shared.delegate as! AppDelegate
        appDelegate.memes.remove(at: index)
    }

    override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
        if (editingStyle == UITableViewCellEditingStyle.delete) {
            tableView.beginUpdates()
            deleteMemesInTableViewCell(indexPath.row)
            tableView.deleteRows(at: [indexPath], with: UITableViewRowAnimation.left)
            tableView.endUpdates()
        }

    }
}

Heres是detailController，名为MemeDetailViewController

    import UIKit

class MemeDetailViewController: UIViewController {

    var meme: SentMemeImage?

    @IBOutlet weak var sentMemesBtn: UIBarButtonItem!
    @IBOutlet weak var editBtn: UIBarButtonItem!
    @IBOutlet weak var sentMemeView: UIImageView!

    override func viewWillAppear(_ animated: Bool) {
        displayMeme()
    }




    func displayMeme() {
        self.sentMemeView.image = self.meme?.memedImage

    }

    @IBAction func launchMemeEditorViewController(_ sender: Any) {
        _ = navigationController?.popViewController(animated: true)

    }

    //unwinding to the view before (the collectionView, or the tableView)

    @IBAction func unwindVC(for unwindSegue: UIStoryboardSegue, towardsViewController subsequentVC: UIViewController) {
        self.dismiss(animated: true, completion: nil)
    }
}

Answer 1

您必须创建DetailView控制器的实例，然后为其属性分配要传递给它的数据。

像：

Home

Answer 2

您需要使用您想要传递的数据更新目标视图控制器（MemeDetailViewController），如第一个示例所示：

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "MemeDetailViewController" ,
    let nextScene = segue.destination as? MemeDetailViewController ,
        let cell = collectionView?.dequeueReusableCell(withReuseIdentifier: "MemeCollectionViewCell", for: IndexPath) {
        let selectedMeme = memes[IndexPath]
        nextScene.meme = selectedMeme

    }
}

如何将数据从collectionView和tableView传递给detailViewController？

2 个答案: