将变量传递给另一个视图控制器并在表视图中显示数据

Question

I'm using Firebase and Swift in my iOS app. I have 2 view controllers with tableviews. I want to pass data from the tableview cell (ie, postkey) to the next view controller upon clicking the cell's accessory button. And I want to retrieve the data from the url https://xxxx.firebaseio.com/users/(uid)/posts/(postkey)/offers and display all the offers that correspond to the postKey in the second tableview. This is the code for the first view controller:

 func tableView(tableView: UITableView, accessoryButtonTappedForRowWithIndexPath indexPath: NSIndexPath){
    let currentCell = tableView.cellForRowAtIndexPath(indexPath) as! FavorCell
    postKey = currentCell.postKey.text
    performSegueWithIdentifier("seguetoAccept", sender: self)
}


 override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    let viewControllerAccept = segue.destinationViewController as! AcceptVC
    viewControllerAccept.postKey = postKey
 //passing the postKey to AcceptVC's postKey    
}

And this one's the code for the second view controller:

override func viewDidLoad() {
    super.viewDidLoad()
    bidTableView.delegate = self
    bidTableView.dataSource = self

    let bidCell = Firebase(url:"https://xxxx.firebaseio.com/users/\(uid)/posts/\(postkey)/offers")


    bidCell.observeEventType(.Value, withBlock: { snapshot in
        print(snapshot.value)
        self.favors = []


        if let snapshots = snapshot.children.allObjects as? [FDataSnapshot]{

            for snap in snapshots {
                print("SNAP: \(snap)")
                if let postdic = snap.value as? Dictionary <String, AnyObject>{
                    let key = snap.key
                    let offer = Offer(bidKey: key, dictionary: postdic)

                    self.favors.append(offer)

                    } 
                }
            }
        self.bidTableView.reloadData()
    })

    }


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

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


func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let favor = favors[indexPath.row]
    if let cell = tableView.dequeueReusableCellWithIdentifier("acceptCell") as? AcceptCell {
        var img: UIImage?
        cell.configureCell(favor)
        return cell
    } else {
        return AcceptCell()
    }
}

The second tableview isn't showing any data. Wish to check if there's an error in my code insofar as retrieving data from Firebase is concerned.

Answer 1

You need to correct your code as below.

func tableView(tableView: UITableView, accessoryButtonTappedForRowWithIndexPath indexPath: NSIndexPath){
    let currentCell = tableView.cellForRowAtIndexPath(indexPath) as! FavorCell
    postKey = currentCell.postKey.text
    performSegueWithIdentifier("seguetoAccept", sender: postKey)
}


override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if segue.identifier == "seguetoAccept" {
        let viewControllerAccept = segue.destinationViewController as! AcceptVC
        let postKey = sender as? String
        viewControllerAccept.postKey = postKey
    }

    //passing the postKey to AcceptVC's postKey
}

You also need to add postKey variable into second view Controller

var postKey:String?