Question

我试图将数据从一个tableView传递到静态一个。我没有使用segue而是使用instantiateviewcontrollerwithidentifier，我不知道我在哪里出错了。我正在使用cloudkit并从icloud获取ckRecords。我有一个collectionView首先我点击一个单元格并显示与该单元格对应的书籍。但是当它们显示在单元格中时，我想点击单元格来调出detailViewController。它现在不工作，无法理解为什么。

import CloudKit

class DetailViewController: UITableViewController {

    @IBOutlet weak var aboutBookLabel: UILabel!
    @IBOutlet weak var bookLengthLabel: UILabel!
    @IBOutlet weak var amazonPriceLabel: UILabel!
    @IBOutlet weak var ebayPriceLabel: UILabel!
    @IBOutlet weak var websitePriceLabel: UILabel!
    @IBOutlet weak var authorLabel: UILabel!
    @IBOutlet weak var bookTitleLabel: UILabel!
    @IBOutlet weak var bookImageView: UIImageView!

    var bookRecord: CKRecord?

    override func viewDidLoad() {
        super.viewDidLoad()
        populateData()
    }


    override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
        return UITableViewAutomaticDimension
    }

    override func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
        cell.backgroundColor = UIColor(red: 27.0/255.0, green: 28.0/255.0 , blue: 32.0/255.0, alpha: 1.0)
    }

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        tableView.deselectRow(at: indexPath, animated: true)
    }

    func populateData() {
        aboutBookLabel.text = bookRecord?.object(forKey: "description") as? String
        bookLengthLabel.text = bookRecord?.object(forKey: "length") as? String
        amazonPriceLabel.text = bookRecord?.object(forKey: "amazon") as? String
        ebayPriceLabel.text = bookRecord?.object(forKey: "ebay") as? String
        websitePriceLabel.text = bookRecord?.object(forKey: "authorPrice") as? String
        authorLabel.text = bookRecord?.object(forKey: "author") as? String
        bookTitleLabel.text = bookRecord?.object(forKey: "name") as? String
        if let imageFile = bookRecord?.object(forKey: "image") as? CKAsset {
            bookImageView.image = UIImage(contentsOfFile: imageFile.fileURL.path)
        }

    }
}

class BooksViewController: UIViewController {

    @IBOutlet weak var tableView: UITableView!

    let cellIdentifier = "bookCell"

    var books = [CKRecord]()

    var sectorTitle = "language"

    override func viewDidLoad() {
        super.viewDidLoad()
        registerNib()
        fetchBooksFromCloud()
        configureTableView()
    }

    func fetchBooksFromCloud() {
        books = [CKRecord]()
        books.removeAll()
        tableView.reloadData()

        let cloudContainer = CKContainer.default()
        let publicDatabase = cloudContainer.publicCloudDatabase
        let predicate = buildBookPredicate()
        let query = CKQuery(recordType: "Book", predicate: predicate)
        query.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: false)]

        let queryOperation = CKQueryOperation(query: query)
        queryOperation.desiredKeys = ["name", "author", "image", "format", "description", "length", "amazon", "ebay", "authorPrice"]
        queryOperation.queuePriority = .veryHigh
        queryOperation.resultsLimit = 25
        queryOperation.recordFetchedBlock = { (record) -> Void in
            self.books.append(record)
        }
        DispatchQueue.global(qos: .userInteractive).async {
            queryOperation.queryCompletionBlock = { (cursor, error) -> Void in
                if let error = error {
                    print("Download failed \(error.localizedDescription)")
                    return
                }

                print("Download Successful")

                OperationQueue.main.addOperation {
                    DispatchQueue.main.async {
                        self.tableView.reloadData()
                    }
                }
            }
        }

        queryOperation.qualityOfService = .userInteractive

        publicDatabase.add(queryOperation)
    }

    private func buildBookPredicate() -> NSPredicate {
        return NSPredicate(format:"self contains '\(sectorTitle)'")
    }

extension BooksViewController: UITableViewDelegate, UITableViewDataSource {

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return books.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: cellIdentifier , for: indexPath) as! BookCell
        let book = books[indexPath.row]
        let bookName = book.object(forKey: "name") as? String
        let authorName = book.object(forKey: "author") as? String
        let image = book.object(forKey: "image") as? CKAsset
        let formatName = book.object(forKey: "format") as? String

        cell.nameLabel.text = bookName
        cell.authorLabel.text = authorName
        cell.formatLabel.text = formatName
        cell.bookImageName.image = UIImage(contentsOfFile: image!.fileURL.path)

        return cell
    }

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        let record = books[indexPath.row]
        if let detailVC = storyboard?.instantiateViewController(withIdentifier: "DetailVC") as? DetailViewController {
            detailVC.bookRecord = record
            navigationController?.pushViewController(detailVC, animated: true)
        }
        tableView.deselectRow(at: indexPath, animated: true)
    }

Answer 1

storyboard的{{1}}属性表示视图控制器所源自的故事板。如果要从同一故事板加载另一个视图控制器，则可以使用它。

但是，如果您要从其他故事板加载UIViewController，则必须先创建UIViewController实例。

你可以这样做。

UIStoryboard

使用storyboard instantiateviewcontrollerwithidentifier在tableViews之间传递数据

1 个答案: