swift update cell accessory type - ios

Question

I am trying to update my table cell accessory type when I tap a cell.
here is the code:
var selectedCellArray :[FriendTableViewCell] = []
var friends: [PFUser] = []
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
var selectedCell = self.tableView(tableView, cellForRowAtIndexPath: indexPath) as FriendTableViewCell
if (selectedCell.accessoryType == UITableViewCellAccessoryType.None){
selectedCell.accessoryType = .Checkmark
selectedCellArray.append(selectedCell)
}else if (selectedCell.accessoryType == UITableViewCellAccessoryType.Checkmark){
selectedCell.accessoryType = .None
var index = 0
for cell in selectedCellArray{
if (cell != selectedCell){
index++
}else{
break
}
}
selectedCellArray.removeAtIndex(index)
}
self.tableView(tableView, cellForRowAtIndexPath: indexPath)
}
and
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
var cell = tableView.dequeueReusableCellWithIdentifier("friend") as? FriendTableViewCell ?? FriendTableViewCell()
var round = 0
var friend: AnyObject = self.friends[indexPath.row]
cell.firstNameLabel.text = friend["firstName"] as? String
cell.lastNameLabel.text = friend["lastName"] as? String
println(selectedCellArray)
round++
var hasFound = false
if (self.checkSelectedArray(selectedCellArray, target: cell)){
cell.accessoryType = .Checkmark
}else{
cell.accessoryType = .None
}
cell.firstNameLabel.sizeToFit()
cell.lastNameLabel.sizeToFit()
return cell
}
func checkSelectedArray(selectedArray:[FriendTableViewCell], target:FriendTableViewCell) -> Bool{
for cell in selectedCellArray{
if cell.isEqual(target){
return true
}
}
return false
}
Also, is there a built-in method like array.contain? Currently, I wrote a function by myself to check if an array has certain element......
Please help me out... I am stuck for this problem for about 8 hours

Answer 1

Storing the reference to the cell isn't a valid strategy as cells can be re-used when the table scrolls. You can't use the current cell accessory to indicate selection state for the same reason.
You can use an NSIndexSet or a Swift dictionary. Here is an implementation using a dictionary -
var selectedCells :Dictionary<String,PFUser>()
var friends: [PFUser] = []
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
let selectedCell = tableView.cellForRowAtIndexPath(indexPath) as FriendTableViewCell
let objectId=friends[indexPath.row].objectId
if (selectedCells[objectId] != nil){
selectedCell.accessoryType = .None
selectedCells.removeValueForKey(objectId)
} else
selectedCell.accessoryType = .Checkmark
selectedCells[objectId]=friends[indexPath.row]
}
tableView.deselectRowAtIndexPath(indexPath, animated:false)
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
var cell = tableView.dequeueReusableCellWithIdentifier("friend") as? FriendTableViewCell ?? FriendTableViewCell()
var round = 0
var friend: AnyObject = self.friends[indexPath.row]
cell.firstNameLabel.text = friend["firstName"] as? String
cell.lastNameLabel.text = friend["lastName"] as? String
if (selectedCells[friend.objectId] != nil){
selectedCell.accessoryType = .Checkmark
} else
selectedCell.accessoryType = .None
}
cell.firstNameLabel.sizeToFit()
cell.lastNameLabel.sizeToFit()
return cell
}