UITableViewCell's background settings are reset on scroll

Question

I have a UITableView Controller in my project. So I made a UITableViewCell setup like here:

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)

    cell.textLabel?.text = "Section: \(indexPath.section). Row: \(indexPath.row)."

    if indexPath.row % 2 == 1 {
        cell.backgroundColor = UIColor.gray
    }

    return cell
}

I want my tableview's cells to be gray if their index is not divisible by 2.

When tableview appears, everything is perfect! But when I scroll up and down, cells starts to change their colors to gray.

So at the end all my cells are gray.

Here are some images:

before

after

score 4 · Accepted Answer · answered Oct 16 '16 at 12:11

4

Try to add an else statement, since the cells are reused.

else {
    cell.backgroundColor = UIColor.white
}

answered Oct 16 '16 at 12:11

Dovahkiin

1,239
11
23

Thanks a lot!) It was so easy!) :D – Alex Vihlayev Oct 16 '16 at 12:17
@AlexVihlayev No problem mate. :) – Dovahkiin Oct 16 '16 at 12:17

score 2 · Answer 2 · answered Oct 16 '16 at 12:14

The problem is that you never set background back to white. Since cells are being reused, at some point you set gray for all of them. Instead you should check the row index every time cell is reused:

cell.backgroundColor = indexPath.row % 2 == 0 ? UIColor.white : UIColor.gray

score 0 · Answer 3 · answered Oct 16 '16 at 12:13

Because tableview reuses the cell

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)

cell.textLabel?.text = "Section: \(indexPath.section). Row: \(indexPath.row)."

if indexPath.row % 2 == 1 {
    cell.backgroundColor = UIColor.gray
}else{
    cell.backgroundColor = YOUR_COLOR
}
return cell

}

Edit : Gellert Lee answered it first and quite simple

UITableViewCell's background settings are reset on scroll

3 Answers3