UITableViewCell Selected Background Color on DidSelectRow - swift

Question

I want to change the background when I select the table. Right now, when I select two tables, the background changes to 2. I just want to change the background of the last table I chose. So just change the background of one table, not two. Change the background of the last painting I chose.
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if tableView == self.tableView1 {
let cell:DeviceTableViewCell2 = tableView1.dequeueReusableCell(withIdentifier: cellId, for: indexPath) as! DeviceTableViewCell2
cell.selectionStyle = .none
cell.backgroundColor = GradientColor(UIGradientStyle.diagonal, frame: self.view.frame, colors: [UIColor.flatPowderBlueDark, UIColor.flatSand])
}
if tableView == self.tableView2 {
let cell:DeviceTableViewCell2 = tableView2.dequeueReusableCell(withIdentifier: cellIdNew, for: indexPath) as! DeviceTableViewCell2
cell.selectionStyle = .none
cell.backgroundColor = GradientColor(UIGradientStyle.diagonal, frame: self.view.frame, colors: [UIColor.flatPowderBlueDark, UIColor.flatSand])
}
if tableView == self.tableView3 {
let cell:DeviceTableViewCell2 = tableView3.dequeueReusableCell(withIdentifier: cellIdNew2, for: indexPath) as! DeviceTableViewCell2
cell.selectionStyle = .none
cell.backgroundColor = GradientColor(UIGradientStyle.diagonal, frame: self.view.frame, colors: [UIColor.flatPowderBlueDark, UIColor.flatSand])
}
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
if tableView == self.tableView1 {
let selectedCell:UITableViewCell = tableView1.cellForRow(at: indexPath)!
selectedCell.contentView.backgroundColor = UIColor.flatGray
}
if tableView == self.tableView2 {
let selectedCell2:UITableViewCell = tableView2.cellForRow(at: indexPath)!
selectedCell2.contentView.backgroundColor = UIColor.flatGray
}
if tableView == self.tableView3 {
let selectedCell3:UITableViewCell = tableView3.cellForRow(at: indexPath)!
selectedCell3.contentView.backgroundColor = UIColor.flatGray
}

Answer 1

Do not change the backgroundColor of the contentView or of the cell itself, use the selectedBackgroundView instead:
cell.backgroundView = UIView()
cell.backgroundView?.backgroundColor = // your color when not selected
cell.selectedBackgroundView = UIView()
cell.selectedBackgroundView?.backgroundColor = // your color when selected
After this initial setup, there is no need to change anything. Everything will work automatically.
Do not set cell.selectionStyle = .none because that will disable selection completely.