Add new listitem in Listview dynamically

[klaydze]

Hi Guys, I populated my listview in android using ArrayAdapter. Populating my listview is easy BUT I'm having trouble adding new item on it dynamically. Kindly check my code.

[Activity(Label = "Country List", MainLauncher = true)]
public class MyListViewActivity : Activity
{
List<string> countries = new List<string>();
ArrayAdapter<string> adapter;
ListView lvw;

    protected override void OnCreate(Bundle bundle)
    {
        base.OnCreate(bundle);
        
        SetContentView(Resource.Layout.ListviewLayout);
        InitCounties();
                                            
        lvw = FindViewById<ListView>(Resource.Id.lvwCountry);
        EditText txtMsg = FindViewById<EditText>(Resource.Id.edit\_text\_out);
        Button btnSend = FindViewById<Button>(Resource.Id.button\_send);

        adapter = new ArrayAdapter<string>(this, Android.Resource.Layout.SimpleListItem1, countries);
        lvw.Adapter = adapter;
        lvw.TextFilterEnabled = true;
        lvw.FastScrollEnabled = true;

        btnSend.Click += delegate(object sender, EventArgs e)
        {
            addItems(txtMsg.Text);
        };
    }
 }

void InitCounties()
{
countries.Add("Philippines");
countries.Add("USA");
countries.Add("Hong Kong");
countries.Add("Singapore");
countries.Add("Russia");
countries.Add("Afghanistan");
countries.Add("Albania");
countries.Add("Algeria");
countries.Add("American Samoa");
countries.Add("Andorra");
}

public void addItems(string newItem)
{
counties.Add(newItem);
adapter.NotifyDataSetChanged();
}

Actually the newitem will add in the collection but when I break and check the adapter, the property Count does not changed and my listview is still the same. I know I'm missing somewhere in my code but I don't know where exactly it is. BTW, I'm using Visual Studio 2010 (Mono for Android) in my code. Thanks

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