我如何在 swift 3 的一个视图控制器中填充两个不同的表视图

Question

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    if tableView == table1{
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell") as! acntTableViewCell
        cell.account.text = account[indexPath.row].email
        return cell
    }
    else if tableView == table2 {
        let cell2 = tableView.dequeueReusableCell(withIdentifier: "cell2")
            as! popTableViewCell

        cell2.pop.text = pop[indexPath.row].answer
        return cell2
    }
}//its give me  error here Missing return  in function

I am going to fill two different tables in one viewcontroller. when I return cell it give me error Missing return in function where I am doing wrong can any one suggest me what's wrong with this code

Answer 1

In the first place, you should compare tables using === (references), not == .

This is one of the cases when an assertion failure is a good way to tell the compiler that no other way of the function exists eg:

if tableView === table1 {
    return ...
} else if tableView === table2 {
    return ...
} else {
    fatalError("Invalid table")
}

You can also use a switch :

switch tableView {
   case table1:
       return ...
   case table2:
       return ...
   default:
       fatalError("Invalid table")
}

Answer 2

Both answers are correct, but I believe the best way to do it would be to separate each table view to have its own data source object, not a view controller. Putting multiple tableview data source protocols adds a decent amount of unnecessary code, and if you refactor them into separate objects, you can help avoid a Massive View Controller.

 class FirstTableViewDataSource : NSObject, UITableViewDataSource {

    var accounts: [ObjectTypeHere]

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

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell") as! AcntTableViewCell
        cell.account.text = accounts[indexPath.row].email
        return cell
    }

}

class SecondTableViewDataSource : NSObject, UITableViewDataSource {

    var pops: [ObjectTypeHere]

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

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell") as! PopTableViewCell
        cell.account.text = pops[indexPath.row].answer
        return cell
    }
}

From there, just update the tableviews to pull from these objects

override func viewDidLoad() {
    super.viewDidLoad()
    self.table1.dataSource = FirstTableViewDataSource()
    self.table2.dataSource = SecondTableViewDataSource()
}

Answer 3

The compiler is analyzing what will happen if tableView is neither table1 nor table2 . If that should happen, the function will exit with nothing to return.

That's an error.

Answer 4

Your cellForRowAt method should always return a cell, so

Try this way

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    if tableView == table1{
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell") as! acntTableViewCell
        cell.account.text = account[indexPath.row].email
        return cell
    }
     //if tableView is not table1 then
    let cell2 = tableView.dequeueReusableCell(withIdentifier: "cell2")
            as! popTableViewCell

     cell2.pop.text = pop[indexPath.row].answer
     return cell2
}

Answer 5

import UIKit

class ViewController: UIViewController {
@IBOutlet weak var table1: UITableView!
@IBOutlet weak var table2: UITableView!
let firstClassRef = FirstTableView()
let secondClassRef = SecondTableView()
override func viewDidLoad() {
    super.viewDidLoad()

   firstClassRef.array1 = ["1","2","3"]
    secondClassRef.array2 = ["1","2","3","1","2","3"]

    self.table1.dataSource = firstClassRef
    self.table2.dataSource = secondClassRef

    self.table1.delegate = firstClassRef
    self.table2.delegate = secondClassRef

    self.table1.reloadData()
    self.table2.reloadData()
 }
}

class FirstTableView: NSObject, UITableViewDataSource, UITableViewDelegate {
var array1 = Array<Any>()

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
    return array1.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
    let cell = tableView.dequeueReusableCell(withIdentifier: "cell1", for: indexPath) as UITableViewCell
    cell.textLabel?.text = array1[indexPath.row] as? String
    cell.backgroundColor = UIColor.yellow
    return cell
}
}

class SecondTableView: NSObject, UITableViewDataSource, UITableViewDelegate {
var array2 = Array<Any>()

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
    return array2.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
    let cell = tableView.dequeueReusableCell(withIdentifier: "cell2", for: indexPath) as UITableViewCell
    cell.textLabel?.text = array2[indexPath.row] as? String
    cell.backgroundColor = UIColor.yellow
    return cell
}
}

Answer 6

Use Switch Statement

import UIKit

class ViewController: UIViewController , UITableViewDelegate , UITableViewDataSource {
    @IBOutlet weak var topTableView: UITableView!
    @IBOutlet weak var downTableview: UITableView!
    var topData : [String] = []
    var downData = [String]()

    override func viewDidLoad() {
        super.viewDidLoad()

        topTableView.delegate = self
        downTableview.delegate = self
        topTableView.dataSource = self
        downTableview.dataSource = self

        for index in 0...20 {
            topData.append("Top Table Row \(index)")
        }

        for index in 10...45 {
            downData.append("Down Table Row \(index)")
        }

    }

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

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        var numberOfRow = 1
        switch tableView {
        case topTableView:
            numberOfRow = topData.count
        case downTableview:
            numberOfRow = downData.count
        default:
            print("Some things Wrong!!")
        }
        return numberOfRow
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        var cell = UITableViewCell()
        switch tableView {
        case topTableView:
            cell = tableView.dequeueReusableCell(withIdentifier: "topCell", for: indexPath)
            cell.textLabel?.text = topData[indexPath.row]
            cell.backgroundColor = UIColor.green
        case downTableview:
            cell = tableView.dequeueReusableCell(withIdentifier: "downCell", for: indexPath)
            cell.textLabel?.text = downData[indexPath.row]
            cell.backgroundColor = UIColor.yellow
        default:
            print("Some things Wrong!!")
        }
        return cell
    }
}