Segue沒有將數據傳遞給ViewController

Question

我正在嘗試從TableView傳遞數據，因此當按下某個單元格時，該單元格上的數據將被傳輸到viewController並在其中顯示它，但是我似乎無法使其正常工作。 我試過這些帖子：

快速segue沒有從tableview傳遞數據

在Swift中將數據從tableView傳遞到ViewController

通過解散數據傳遞數據

但是我收到一個導致應用程序崩潰的錯誤，或者它什么都不顯示。 我想做的是讓一個用戶對另一個用戶發布的帖子發表評論，所以我試圖從該帖子中獲取信息以詳細顯示它，但這就是我遇到的麻煩。 這是我用來從表格視圖傳遞數據的功能：

func objectAtIndexPath(indexPath: NSIndexPath) -> PFObject {
    return self.timelineData[indexPath.row] as! PFObject
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
    if(segue.identifier == "lookPosts"){
        let VC = segue.destinationViewController as! DetailViewContoller
        let indexPath: NSIndexPath! = self.tableView.indexPathForSelectedRow()
        VC.post = self.objectAtIndexPath(indexPath!) as PFObject
    }
}

這是DetailViewController的類：

import UIKit
import Parse

class DetailViewContoller: UIViewController, UITableViewDelegate, UITextViewDelegate {

    @IBOutlet weak var usernameLabel: UILabel!
    @IBOutlet weak var postTextView: UITextView!
    @IBOutlet weak var commentTableView: UITableView!

    var post: PFObject?
    var commentView: UITextView?
    var footerView: UIView?
    var contentHeight: CGFloat = 0

    var comments: [String]?
    let FOOTERHEIGHT : CGFloat = 50;

    override func viewDidLoad() {
        super.viewDidLoad()

        commentTableView.delegate = self

        /* Setup the keyboard notifications */
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyBoardWillShow:", name: UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyBoardWillHide:", name: UIKeyboardWillHideNotification, object: nil)

        //gets the current user username
        usernameLabel.text = PFUser.currentUser()!.username as String?

        if(post?.objectForKey("comments") != nil) {
            comments = post?.objectForKey("comments") as? [String]
        }

        println(post)
        println(post?.objectForKey("content"))
        //self.postTextView.text = post?.objectForKey("content") as? String
    }

    override func viewWillAppear(animated: Bool) {
        super.viewDidAppear(animated)

        self.postTextView.text = post?.objectForKey("content") as? String
        println(postTextView.text)
    }


    func keyBoardWillShow(notification: NSNotification) {
        var info:NSDictionary = notification.userInfo!
        var keyboardSize = (info[UIKeyboardFrameBeginUserInfoKey] as! NSValue).CGRectValue()

        var keyboardHeight:CGFloat =  keyboardSize.height - 40


        var animationDuration:CGFloat = info[UIKeyboardAnimationDurationUserInfoKey] as! CGFloat

        var contentInsets: UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, keyboardHeight, 0.0);
        self.commentTableView.contentInset = contentInsets
        self.commentTableView.scrollIndicatorInsets = contentInsets

    }

    func keyBoardWillHide(notification: NSNotification) {

        self.commentTableView.contentInset = UIEdgeInsetsZero
        self.commentTableView.scrollIndicatorInsets = UIEdgeInsetsZero
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()

    }

    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        if let count = comments?.count {
            return count
        }
        return 0
    }

    func numberOfSectionsInTableView(tableView: UITableView) -> Int {
        return 1
    }

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        let cell = commentTableView.dequeueReusableCellWithIdentifier("commentCell", forIndexPath: indexPath) as! CommentTableViewCell
        cell.commentLabel?.text = comments![indexPath.row]
        return cell
    }

    func tableView(tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat {
        if self.footerView != nil {
            return self.footerView!.bounds.height
        }
        return FOOTERHEIGHT
    }

    func tableView(tableView: UITableView, viewForFooterInSection section: Int) -> UIView? {
        footerView = UIView(frame: CGRect(x: 0, y: 0, width: commentTableView.bounds.width, height: FOOTERHEIGHT))
        footerView?.backgroundColor = UIColor(red: 243.0/255, green: 243.0/255, blue: 243.0/255, alpha: 1)
        commentView = UITextView(frame: CGRect(x: 10, y: 5, width: commentTableView.bounds.width - 80 , height: 40))
        commentView?.backgroundColor = UIColor.whiteColor()
        commentView?.textContainerInset = UIEdgeInsetsMake(5, 5, 5, 5)
        commentView?.layer.cornerRadius = 2
        commentView?.scrollsToTop = false

        footerView?.addSubview(commentView!)
        let button = UIButton(frame: CGRect(x: commentTableView.bounds.width - 65, y: 10, width: 60 , height: 30))
        button.setTitle("Reply", forState: UIControlState.Normal)
        button.backgroundColor = UIColor(red:  0/0.0, green: 179/255.0, blue: 204/255.0, alpha: 100.0/100.0)
        button.layer.cornerRadius = 5
        button.addTarget(self, action: "reply", forControlEvents: UIControlEvents.TouchUpInside)
        footerView?.addSubview(button)
        commentView?.delegate = self
        return footerView
    }


    //Hide keyboard after touching background
    override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
        self.view.endEditing(true)
    }

    //remaining characters
    func textView(textView: UITextView, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool{

        if (text == "\n") {
            textView.resignFirstResponder()
        }

        return true
    }

    func reply() {
        post?.addObject(commentView!.text, forKey: "comments")
        post?.saveInBackground()
        if let tmpText = commentView?.text {
            comments?.append(tmpText)
        }
        commentView?.text = ""
        println(comments?.count)
        self.commentView?.resignFirstResponder()
        self.commentTableView.reloadData()
    }
}

所以我的問題是：還有另一種傳遞數據的方式嗎？ 還是數據沒有通過我在做什么錯？

Answer 1

這是達到上述目的的一種方法：

如果數據不大，則可以使用NSUserDefaults 。

首先將您的數據存儲到內存中：

NSUserDefaults.standardUserDefaults().setObject(yourObject, forKey: "yourKey")

在另一個viewController中從內存中讀取數據：

let yourObject = NSUserDefaults.standardUserDefaults().objectForKey("yourKey") as! PFObject

希望能幫助到你。