使用Swift 3在Tableview Firebase中重新加载数据

Question

I follow a video tutorial for making twitter clone. This tutorial is written with swift 2 I guess. I tried to apply for Swift 3. But in 3th video I have a problem. I can save tweets but I don't know how it can be shown in tableview. He is using this line:

let tweet = tweets[(self.tweets.count-1) - indexPath.row]!.value["text"] as! String

Video Series: twitter clone with firebase

Project here: Github Link

My problem here:

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

    let cell: HomeViewTableViewCell = tableView.dequeueReusableCellWithIdentifier("HomeViewTableViewCell", forIndexPath: indexPath) as! HomeViewTableViewCell


    let tweet = tweets[(self.tweets.count-1) - indexPath.row]!.value["text"] as! String

    cell.configure(nil,name:self.loggedInUserData!.value["name"] as! String,handle:self.loggedInUserData!.value["handle"] as! String,tweet:tweet)


    return cell
}

Error: "Ambiguous reference to member count".

Answer 1

So in order to show the tweet you need to add a observer to your Firebase Real-Time Database.

self.databaseRef.child("user_profiles").child(self.loggedInUser!.uid).observeSingleEventOfType(.Value) { (snapshot:FIRDataSnapshot) in

        //store the logged in users details into the variable 
        self.loggedInUserData = snapshot
        print(self.loggedInUserData)

        //get all the tweets that are made by the user

        self.databaseRef.child("tweets/\(self.loggedInUser!.uid)").observeEventType(.ChildAdded, withBlock: { (snapshot:FIRDataSnapshot) in


            self.tweets.append(snapshot)


            self.homeTableView.insertRowsAtIndexPaths([NSIndexPath(forRow:0,inSection:0)], withRowAnimation: UITableViewRowAnimation.Automatic)

            self.aivLoading.stopAnimating()

        }){(error) in

            print(error.localizedDescription)
        }

    }

If you look at the following section,

self.databaseRef.child("tweets/\(self.loggedInUser!.uid)").observeEventType(.ChildAdded, withBlock: { (snapshot:FIRDataSnapshot) in
        self.tweets.append(snapshot)    
        self.homeTableView.insertRowsAtIndexPaths([NSIndexPath(forRow:0,inSection:0)], withRowAnimation: UITableViewRowAnimation.Automatic)

        self.aivLoading.stopAnimating()

    }){(error) in

        print(error.localizedDescription)
    }

He is adding an observer to Database and anytime there is node getting added to the reference, the above code will be triggered. Check if you've done this correctly.

In case you've done this correctly, make sure you've added the observer to exact node. Here, the observer is attached to a node called tweet --> userID . If you have different configuration of database, your reference will be different.

As you are learning, I would leave the conversion to Swift 3 syntax on you.

Answer 2

Finally I solved my problem. Update like this for Swift 3.1:

self.homeTableView.insertRows(at: [IndexPath(row:self.tweets.count-1,section:0)], with: UITableViewRowAnimation.automatic)

I used above code in viewDidLoad. And I use tweets[indexPath.row].