Missing return UITableViewCell

Question

I am sure this question have been asked before but I can't find an answer that solves my problem with nested if-else and switch-case logic.
I have a UITableView with two sections, each sections has two custom cells. That is it it. 4 cells. But no matter what I do I get "Missing return in a function expected to return UITableViewCell"

Question How can I change this setup so that I get an else statement at the bottom that will satisfy swift logic?

Any help would be very much appreciated

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

    if indexPath.section == 0{

        switch (indexPath.row) {
        case 0:
            let cell0: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell0", forIndexPath: indexPath) as! SettingsCell
        cell0.backgroundColor = UIColor.redColor()
        break

        case 1:
            let cell1: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell1", forIndexPath: indexPath) as! SettingsCell
        cell1.backgroundColor = UIColor.whiteColor()
         break

        default:
            break
        }
    }

    if indexPath.section == 1{

        switch (indexPath.row) {
        case 0:
            let cell10: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell10", forIndexPath: indexPath) as! SettingsCell
        cell10.backgroundColor = UIColor.redColor()
        break

        case 1:
            let cell11: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell11", forIndexPath: indexPath) as! SettingsCell
        cell11.backgroundColor = UIColor.whiteColor()
         break

        default:
            break

        }
    }
}

What do you mean by that. I want a tableView with 2 sections, each with two cells. — KML, May 12 '15 at 11:31
@karlml write. return cell statement in cellForRowAtIndexPath method — Ashok Londhe, May 12 '15 at 11:34
Haha! I love it!! Why do error messages even bother having messages at all... — Mika, May 12 '15 at 11:35
@karlml you need to mention your tableview cell name in return statement... i think its SettingsCell.. so write this line return SettingsCell — Ashok Londhe, May 12 '15 at 11:45

Martin R · Accepted Answer · 2015-05-12T13:13:28.323

Declare the cell at the start of the method,
assign a value to the cell depending on section and row number,
throw a fatalError() in all cases that "should not occur",
return the cell.

Also note that the break statements are not needed. The default behavior in Swift is not to fall through to the next case.

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

    let cell: SettingsCell

    switch(indexPath.section) {
    case 0:
        switch (indexPath.row) {
        case 0:
            cell = tableView.dequeueReusableCellWithIdentifier("cell0", forIndexPath: indexPath) as! SettingsCell
            cell.backgroundColor = UIColor.redColor()

        case 1:
            cell = tableView.dequeueReusableCellWithIdentifier("cell1", forIndexPath: indexPath) as! SettingsCell
            cell.backgroundColor = UIColor.whiteColor()

        default:
            fatalError("Unexpected row \(indexPath.row) in section \(indexPath.section)")
        }
    case 1:
        switch (indexPath.row) {
        case 0:
            cell = tableView.dequeueReusableCellWithIdentifier("cell10", forIndexPath: indexPath) as! SettingsCell
            cell.backgroundColor = UIColor.redColor()

        case 1:
            cell = tableView.dequeueReusableCellWithIdentifier("cell11", forIndexPath: indexPath) as! SettingsCell
            cell.backgroundColor = UIColor.whiteColor()

        default:
            fatalError("Unexpected row \(indexPath.row) in section \(indexPath.section)")

        }
    default:
        fatalError("Unexpected section \(indexPath.section)")

    }
    return cell
}

The fatalError() error function is marked as @noreturn, so the compiler knows that program execution will not continue from the default cases. (This also helps to find logic errors in the program.)

The compiler verifies that a value is assigned to cell in all other cases.

The possibility to initialize a constant (let cell ...) in this way is new in Swift 1.2.

Alternatively, you can create a cell and return it "immediately" in each case:

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

    switch(indexPath.section) {
    case 0:
        switch (indexPath.row) {
        case 0:
            let cell = tableView.dequeueReusableCellWithIdentifier("cell0", forIndexPath: indexPath) as! SettingsCell
            cell.backgroundColor = UIColor.redColor()
            return cell

        case 1:
            let cell = tableView.dequeueReusableCellWithIdentifier("cell1", forIndexPath: indexPath) as! SettingsCell
            cell.backgroundColor = UIColor.whiteColor()
            return cell

        default:
            fatalError("Unexpected row \(indexPath.row) in section \(indexPath.section)")
        }
    case 1:
        switch (indexPath.row) {
        case 0:
            let cell = tableView.dequeueReusableCellWithIdentifier("cell10", forIndexPath: indexPath) as! SettingsCell
            cell.backgroundColor = UIColor.redColor()
            return cell

        case 1:
            let cell = tableView.dequeueReusableCellWithIdentifier("cell11", forIndexPath: indexPath) as! SettingsCell
            cell.backgroundColor = UIColor.whiteColor()
            return cell

        default:
            fatalError("Unexpected row \(indexPath.row) in section \(indexPath.section)")

        }
    default:
        fatalError("Unexpected section \(indexPath.section)")
    }
}

Again, calling fatalError() solves the "missing return expected" compiler error.

This pattern can be useful if there are different kinds of cells (with different classes) created in each case.

This crash: fatal error: unexpectedly found nil while unwrapping an Optional value on line: return cell — KML, May 12 '15 at 12:05
But it does compile now? – Have you verified that `dequeueReusableCellWithIdentifier` returns a valid cell? Did you call `registerNib(..)` or `registerClass(...)` or have you defined prototype cells in the Storyboard (for all cell identifiers)? — Martin R, May 12 '15 at 12:07
All my prototype cells are custom.. should there be one that is empty? — KML, May 12 '15 at 12:11
@karlml: Are the prototype cells defined in the Storyboard? Have you assigned cell identifiers to each prototype cell (the same ones that you use in the code) ? — Martin R, May 12 '15 at 12:13
If I declare var cell: SettingsCell! I get no error but the app crash. If I declare var cell: SettingsCell I get error "Variable 'cell' used before being initialized" — KML, May 12 '15 at 12:15
@karlml: Have you used the exact code from my answer? I do not get any compiler error for `var cell: SettingsCell `. – Perhaps you forgot to assign a value in one of the cases? — Martin R, May 12 '15 at 12:17

Raheel Sadiq · Answer 2 · 2015-09-03T13:59:20.913

2

You must return a cell, if the section is number 2 this methods won't be returning anything, well it's the case when u specify secitons more than two. Solution

Second "if" will be "else" part
Limit number of section

edited Sep 03 '15 at 13:59

answered May 12 '15 at 11:32

Raheel Sadiq

9,847
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Manuel Escrig · Answer 3 · 2015-05-12T11:45:58.273

You're missing in you method the return statement.

Example with return statement.

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

    if indexPath.section == 0{

        switch (indexPath.row) {
        case 0:
            let cell: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell0", forIndexPath: indexPath) as! SettingsCell
        cell.backgroundColor = UIColor.redColor()
        break

        case 1:
            let cell: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell1", forIndexPath: indexPath) as! SettingsCell
        cell.backgroundColor = UIColor.whiteColor()
         break

        default:
            let cellId: NSString = "Cell"
            var cell: UITableViewCell = tableView.dequeueReusableCellWithIdentifier(cellId) as UITableViewCell
            break
        }
    }

    if indexPath.section == 1{

        switch (indexPath.row) {
        case 0:
            let cell: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell10", forIndexPath: indexPath) as! SettingsCell
        cell.backgroundColor = UIColor.redColor()
        break

        case 1:
            let cell: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell11", forIndexPath: indexPath) as! SettingsCell
        cell.backgroundColor = UIColor.whiteColor()
         break

        default:
             let cellId: NSString = "Cell"
             var cell: UITableViewCell = tableView.dequeueReusableCellWithIdentifier(cellId) as UITableViewCell
            break

        }
    }
    return cell
}

"return cell" gives error "Use of unresolved identifier 'cell'" — KML, May 12 '15 at 11:39
@karlml you need to mention your tableview cell name in return statement... i think its SettingsCell.. so write this line return SettingsCell. — Ashok Londhe, May 12 '15 at 11:46
I edit it and put more information. In the default case you need to create a cell too. Even though it is not suppose to be never reached. — Manuel Escrig, May 12 '15 at 11:46
hmm, well "return cell" still gives error "Use of unresolved identifier 'cell'" — KML, May 12 '15 at 11:51

score 0 · Answer 4 · answered May 12 '15 at 11:51

you can use else if like this :

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

if indexPath.section == 0{

    switch (indexPath.row) {
    case 0:
        let cell: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell0", forIndexPath: indexPath) as! SettingsCell
    cell.backgroundColor = UIColor.redColor()
    break

    case 1:
        let cell: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell1", forIndexPath: indexPath) as! SettingsCell
    cell.backgroundColor = UIColor.whiteColor()
     break

    default:
        break
    }


    else if indexPath.section == 1{

    switch (indexPath.row) {
    case 0:
        let cell: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell10", forIndexPath: indexPath) as! SettingsCell
    cell.backgroundColor = UIColor.redColor()
    break

    case 1:
        let cell: SettingsCell! = tableView.dequeueReusableCellWithIdentifier("cell11", forIndexPath: indexPath) as! SettingsCell
    cell.backgroundColor = UIColor.whiteColor()
     break

    default:
        break

    }
}
return cell
}
}

it may help you try it

else if indexPath.section == 1{ gives error "Expected expression" — KML, May 12 '15 at 11:55
ohh !! don`t worry , check your code again and check expressions. it will resolve your problem. — Subhash Sharma, May 12 '15 at 12:01

Missing return UITableViewCell

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