Swift dictionary deletes previous data when appending new data - ios

Question

I have a swift dictionary with custom objects and I use it to fill my UITableview. However, when I fill the dictionary, I realize that it deletes previous data when I append a new data to it. The related code blocks like below:
var dict = Dictionary<ListItem, [ListItem]>()
func numberOfSectionsInTableView(tableView: UITableView) -> Int
{
return 1
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
return self.dict.keys.array.count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
{
var cell: CategoryCell! = tableView.dequeueReusableCellWithIdentifier("categoryCell", forIndexPath: indexPath) as? CategoryCell
if(cell == nil)
{
cell = CategoryCell(style: UITableViewCellStyle.Default, reuseIdentifier: "categoryCell")
}
else
{
cell.ClearCurrentCellContext(cell.image, labelTitle: cell.lblCategory, labelDescription: cell.lblDescription)
}
if let ip = indexPath as NSIndexPath?
{
let key = Array(self.dict.keys)[ip.row] as ListItem
cell.SetCell(key, image: cell.image, labelTitle: cell.lblCategory, labelDescription: cell.lblDescription)
}
return cell
}
And I fill the dictionary inside of this block:
Alamofire.request(.POST, WSConstants.WebServiceAddress, parameters: nil)
.responseJSON
{(request, response, JSON, error) in
if let jsonResult: NSDictionary = JSON as? NSDictionary
{
if let categories = jsonResult[WSConstants.CATEGORIES] as? NSDictionary
{
if let wsStatus = categories.valueForKey(WSConstants.WS_STATUS) as? String
{
if(wsStatus == "ok")
{
var mainObj: NSDictionary!
var mainItem: ListItem!
for(var i=0; i<mainJSONArray.count; i++)
{
mainObj = mainJSONArray.objectAtIndex(i) as! NSDictionary
mainItem = ListItem()
mainItem.itemId = mainObj.valueForKey(WSConstants.ID) as! Int
mainItem.itemName = mainObj.valueForKey(WSConstants.TITLE) as! String
mainItem.itemDescription = mainObj.valueForKey(WSConstants.DESCRIPTION) as! String
mainItem.itemIcon = mainObj.valueForKey(WSConstants.ICON) as! String
mainItem.parentId = mainObj.valueForKey(WSConstants.PARENT) as! Int
mainItem.postCount = mainObj.valueForKey(WSConstants.POST_COUNT) as! Int
if let subJSONArray = mainObj.valueForKey(WSConstants.SUB) as? NSArray
{
var midCategoryList: [ListItem]! = [ListItem]()
var subObj: NSDictionary!
var subItem: ListItem!
for(var i=0; i<subJSONArray.count; i++)
{
subObj = subJSONArray.objectAtIndex(i) as! NSDictionary
subItem = ListItem()
subItem.itemId = subObj.valueForKey(WSConstants.ID) as! Int
subItem.itemName = subObj.valueForKey(WSConstants.TITLE) as! String
subItem.itemDescription = subObj.valueForKey(WSConstants.DESCRIPTION) as! String
subItem.itemIcon = subObj.valueForKey(WSConstants.ICON) as! String
subItem.parentId = subObj.valueForKey(WSConstants.PARENT) as! Int
subItem.postCount = subObj.valueForKey(WSConstants.POST_COUNT) as! Int
midCategoryList.append(subItem)
subItem = nil
subObj = nil
}
// The code below line fills the dictionary with key and its values
self.dict[mainItem] = midCategoryList
midCategoryList = nil
}
mainItem = nil
mainObj = nil
}
Utility.ReloadTableViewDataWithAnimations(self.categoryTableView)
}
}
}
}
ListItem class:
class ListItem: Serializable, Hashable, NSCoding
{
var uniqueID: Int = 0
override var hashValue: Int { return uniqueID.hashValue }
var itemId: Int
var itemName: String!
var itemIcon: String!
var itemDescription: String!
var parentId: Int!
var postCount: Int!
var content: String!
override init()
{
self.itemId = 0
self.itemName = ""
self.itemIcon = ""
self.parentId = 0
self.postCount = 0
self.content = ""
self.itemDescription = ""
}
init(itemId: Int, itemName: String!, itemIcon: String!, itemDescription: String!, parentId: Int!, postCount: Int, content: String!, date: String!, url: String!)
{
self.itemId = itemId
self.itemName = itemName
self.itemIcon = itemIcon
self.parentId = parentId
self.postCount = postCount
self.content = content
self.itemDescription = itemDescription
}
deinit
{
}
required init(coder aDecoder: NSCoder)
{
self.itemId = aDecoder.decodeIntegerForKey("itemId") as Int
self.itemName = aDecoder.decodeObjectForKey("itemName") as! String
self.itemIcon = aDecoder.decodeObjectForKey("itemIcon") as! String
self.itemDescription = aDecoder.decodeObjectForKey("itemDescription") as! String
}
func encodeWithCoder(aCoder: NSCoder)
{
aCoder.encodeInteger(self.itemId, forKey: "itemId")
aCoder.encodeObject(self.itemName, forKey: "itemName")
aCoder.encodeObject(self.itemIcon, forKey: "itemIcon")
aCoder.encodeObject(self.itemDescription, forKey: "itemDescription")
}
}
func ==(lhs: ListItem, rhs: ListItem) -> Bool
{
return lhs.uniqueID == rhs.uniqueID
}
Is this a swift bug or I make some mistakes to fill it ?
Thank you for your answers
King regards
Solution:
The reason of the problem is that using == instead of === in ListItem class. Daniel T.'s solution is the right answer. Thank you all.

Answer 1

Without seeing more code, my guess is that the problem lies in your ListItem's == operator. The following code does not exhibit the problem you are describing:
//: Playground - noun: a place where people can play
class ListItem: Hashable {
var itemId: Int = 0
var itemName: String = ""
var itemDescription: String = ""
var itemIcon: String = ""
var parentId: Int = 0
var postCount: Int = 0
var hashValue: Int {
return itemId.hashValue
}
}
func ==(lhs: ListItem, rhs: ListItem) -> Bool {
return lhs === rhs // simple identity
}
var dict = Dictionary<ListItem, [ListItem]>()
let arr = [ListItem(), ListItem()]
dict[ListItem()] = arr
dict[ListItem()] = arr
dict.keys.array.count