Change only one specific tableView row height

I'm looking for a way to change a specific row in my tableView.

I'm using a Notification to check when I do an action in my cell. According to the answer, my goal is to display the next row.

By default, my cell have this property.

if (indexPath.row == 5){
    tableView.rowHeight = 0.0
}

if (indexPath.row == 6){
    tableView.rowHeight = 0.0
}

return cell

My goal when I'm in my notification is to change the row height value for the fifth row.

Thank you for your help

You could use a Set<IndexPath> and your tableView delegate methods to achieve this.

Say you have a set of selected index paths selectedIndexPaths and heights largeHeight and normalHeight. Your heightForRow func could look like this:

func tableView(_ tableView: UITableView, heigthForRowAt indexPath: IndexPath) -> CGFloat {
    guard !selectedIndexPaths.contains(indexPath) else {
        return largeHeight
    }

    return normalHeight
}

Then you could change the height dynamically the following way:

/// Convenience method for selecting an index path
func select(indexPath: IndexPath, completion: ((Bool) -> Void)? = nil){
    selectedIndexPaths.insert(indexPath)
    tableView.performBatchUpdates({
        self.tableView.reloadRows(at: [indexPath], with: .none)
    }, completion: completion)
}

In your tableView delegate, you could call this method in didSelect:

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    select(indexPath: indexPath)
}

Do the same if you have a method responding to your notification (assuming you placed your indexPath in your notification's userInfo, under the key "indexPathKey"):

func notifiedShouldEnlargeRow(aNotification: Notification) {
    guard let indexPath = aNotification.userInfo["indexPathKey"] as? IndexPath else { return }
    select(indexPath: indexPath)
}

For reference, look at performBatchUpdates(_:completion) and reloadRows(at:with:).