在Swift中自定义单元格之间切换

Question

I'm trying to switch between two custom cell-classes in swift, but I can't seem to figure out how to return the cell.

My code looks like this, and the error is in the last line:

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

    if istrue{
    var cell: CustomTableCell = self.tv.dequeueReusableCellWithIdentifier("cell") as CustomTableCell

        let data = myList[indexPath.row] as Model

        cell.customLabel.text = data.username
        cell.dateLabel.text = printDate(data.date)
        return cell

    }else{
        var cell: CustomTableCell2 = self.tv.dequeueReusableCellWithIdentifier("cell") as CustomTableCell2

        let data = myList[indexPath.row] as Model

        cell.titleLabel.text = data.username
        cell.dateLabel2.text = printDate(data.date)

     return cell
    }

}return nil

I've also tried to "return cell" in the last line and to delete the other two lines of "return cell" in the if- and else-statements but that didn't work, it just gives me the error saying "cell" is an unresolved identifier.

I've never done this before so I'm not sure if this is the right way of tackling the problem either.

Any suggestions on how to proceed would be appreciated.

Answer 1

Define a variable of UITableViewCell type and initialize it in both the if and the else branches, then use it as the return value:

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

    var retCell: UITableViewCell

    if istrue{
        var cell: CustomTableCell = self.tv.dequeueReusableCellWithIdentifier("cell") as CustomTableCell

        let data = myList[indexPath.row] as Model

        cell.customLabel.text = data.username
        cell.dateLabel.text = printDate(data.date)

        retCell = cell

    }else{
        var cell: CustomTableCell2 = self.tv.dequeueReusableCellWithIdentifier("cell") as CustomTableCell2

        let data = myList[indexPath.row] as Model

        cell.titleLabel.text = data.username
        cell.dateLabel2.text = printDate(data.date)

        retCell = cell
    }

    return retCell
}

Note that you cannot return nil because the return type of this method is a non-optional UITableViewCell , so it must always be an instance of (a class derived from) UITableViewCell .

Alternatively, you can just return the cell as you do on each of the if and else branches, but remove the ending return out of the if/else scope - it's not needed. Moreover, in your code it is also misplaced because out of the method scope.

Personal note: in functions I usually avoid return statements in the middle of the body, preferring a single exit path at the end - that's just a personal preference, so feel free to choose the one that you like more.