I agree with "before adding the item to list count it. – Shujaat Siddiqui", but also you cold add Linq or For cicle, to check if ID of the Item already exists, and count the unique ones.
Something like:
int NewItemsCount = 0;
for (int i = 0; i<XmlDataProvider.Items.Count; i++)
{
bool IsOld=false;
//Loop throu all items in existing
for (int o =0; i<NewData.Items.Count;i++)
{
if(XmlDataProvider.Items[i].ID==NewData.Items[o].ID)
{
IsOld = true;
break;
}
}
if(!IsOld)
{
NewItemsCount++;
}
}
More detailed:
First time when you get the news, you do something like this:
For example you have some model for your news:
class Item
{
string guid;
string title;
...
}
And you get your news like:
List news = XML.Deserialize(response.GetResponse()) // can't remember by memory, but this is your response from server deserialized using XML deserializer
Then you populate your ListBox with List news, like this:
ListBox.DataSource = news OR using for/forin and ListBox.Items.Add();
Now you get the update from the server:
List news = XML.Deserialize(response.GetResponse()) // can't remember by memory, but this is your response from server deserialized using XML deserializer
Now you should check how much new items were added ( before adding new items to ListBox ), you should do something like:
a) if you used ListBox.DataSource = news
List<Item> OldNews = (List<Item>)ListBox.DataSource;
int newUniqueNewsCount = 0;
foreach ( Item newObj in news ) // loop through new items that you just got as update from server
{
bool IsOld = false;
foreach ( Item obj in OldNews) // loop through old items
{
if(obj.guid==objNew) //check if this GUID already existed
{
IsOld = true;
break; //end the looping
}
}
if(!IsOld)
{
// If code ran in here then this GUID is new and then this news is new so +1
newUniqueNewsCount ++;
}
}
After this code ran you can use newUniqueNewsCount to show the new items count in UI.
