How to bind List<object> dynamically to a DataGrid in WPF?

Question

i want to bind list to a datagrid dynamically, following code works for first time, if click add again it is not getting populated in the data grid.

       private List<Item> PopulateItemList()
    {
        return itemLst;
    }
    private void btnAdd_Click(object sender, RoutedEventArgs e)
    {
        Item item = new Item();
        item.Item1 = txtItem.Text;
        itemLst.Add(item);
        grdItem.ItemsSource = PopulateItemList();

    }
    private List<Item> itemLst = new List<Item>();

    private void Page_Loaded(object sender, RoutedEventArgs e)
    {
        itemLst.Clear(); 

    }

Thanks.

Answer 1

You should use an ObservableCollection<T> instead of List<T> .

ObservableCollection<T> implements INotifyCollectionChanged , which will tell WPF when you add or remove items.

Answer 2

Either you should use ObservableCollection as suggested by Slaks. Otherwise you have to set the datatgrid itemSource null first before populating it again to some other value. But i would strongly suggest you to use ObservableCollection and you can set it to datagrid's ItemSource in the UserControl's constructor instead of setting it again.