UITableView in Swift

Question

I'm struggling to figure out what's wrong with this code snippet. This is currently working in Objective-C, but in Swift this just crashes on the first line of the method. It shows an error message in console log: `Bad_Instruction`. ``` func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell! { var cell : UITableViewCell = tableView.dequeueReusableCellWithIdentifier("Cell") as UITableViewCell if (cell == nil) { cell = UITableViewCell(style: UITableViewCellStyle.Value1, reuseIdentifier: "Cell") } cell.textLabel.text = "TEXT" cell.detailTextLabel.text = "DETAIL TEXT" return cell } ```

Accepted Answer

Also see matt's answer which contains the second half of the solution

Let's find a solution without creating custom subclasses or nibs

The real problem is in the fact that Swift distinguishes between objects that can be empty (`nil`) and objects that can't be empty. If you don't register a nib for your identifier, then `dequeueReusableCellWithIdentifier` can return `nil`.

That means we have to declare the variable as optional:

```
var cell : UITableViewCell?
```

and we have to cast using `as?` not `as`

```
//variable type is inferred
var cell = tableView.dequeueReusableCellWithIdentifier("CELL") as? UITableViewCell

if cell == nil {
    cell = UITableViewCell(style: UITableViewCellStyle.Value1, reuseIdentifier: "CELL")
}

// we know that cell is not empty now so we use ! to force unwrapping but you could also define cell as
// let cell = (tableView.dequeue... as? UITableViewCell) ?? UITableViewCell(style: ...)

cell!.textLabel.text = "Baking Soda"
cell!.detailTextLabel.text = "1/2 cup"

cell!.textLabel.text = "Hello World"

return cell
```

UITableView in Swift

Solution

Problem

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