Multiple selection UITableView without dequeueReusableCellWithIdentifier - ios

Question

When selecting multiple cells in my tabeview the cells out of view are being selected too. I understand that this is because i am reusing the cell and its maintaining its selection as i scroll down. I have found a few people with similar issues but cant translate their solutions across to resolve my issue. I have tried not dequeing a cell and just use:
let cell = NewBillSplitterItemCell()
but get:
unexpectedly found nil while unwrapping an Optional value
on the line:
cell.currentSplitters.text = splitterList
in the following code:
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
fetchBillItems()
let cell: NewBillSplitterItemCell = tableView.dequeueReusableCellWithIdentifier("NewBillSplitterItemCell") as! NewBillSplitterItemCell
let item = allItems[indexPath.row]
let numberOfSplitters = item.billSplitters?.count
if numberOfSplitters == 0 {
cell.currentSplitters.text = "No one is paying for this item yet."
} else {
var splitterList = "Split this item with "
let itemSplitters = item.billSplitters?.allObjects as! [BillSplitter]
for i in 0...Int((numberOfSplitters)!-1) {
if numberOfSplitters == 1 {
splitterList += "\(itemSplitters[i].name!)"
} else {
splitterList += ", \(itemSplitters[i].name!)"
}
}
cell.currentSplitters.text = splitterList
}
cell.name.text = item.name
cell.price.text = "£\(item.price!)"
return cell
}
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
if let cell = tableView.cellForRowAtIndexPath(indexPath) {
if cell.accessoryType == .Checkmark
{
cell.accessoryType = .None
selectedItems.removeAtIndex(selectedItems.indexOf(allItems[indexPath.row])!)
} else {
cell.accessoryType = .Checkmark
selectedItems.append(allItems[indexPath.row])
}
}
}
I dont quite understand what to do and any help would be great. Thanks

Answer 1

In addition to what #Mike said, inside of cellForRowAtIndexPath you need an additional check because cells get reused.
Something along the line
let isSelected = selectedItems[indexPath.row].selected
if isSelected{
cell.accessoryType = .Checkmark
} else {
cell.accessoryType = .None
}
Same thing inside of didSelectRowAtIndexPath you should update the data source instead of relying on the UI of your cell for that condition.

Answer 2

Assuming your cell is nil, you should use
let cell = tableView.dequeueReusableCellWithIdentifier("..." forIndexPath:indexPath) as! NewBillSplitterItemCell
instead of
let cell= tableView.dequeueReusableCellWithIdentifier("...") as! NewBillSplitterItemCell
This ensures that cell will never be nil.
Also, I would check if the correct identifier is being used in all of your .xib .storyboard files.