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Hello,

I have a simple listview, one label and one entry cell. Whenever i type something in entry cell value, underlying ObservableCollection is not updating.
Here is my code.

----------------- Model
public class TicketItem : INotifyPropertyChanged
{
[PrimaryKey, AutoIncrement]
public String Description { get; set; }

    private Double? _quantityNeeded;
    public Double? QuantityNeeded
    {
        get { return _quantityNeeded; }
        set { _quantityNeeded = value; OnPropertyChanged("QuantityNeeded"); }
    }

    public event PropertyChangedEventHandler PropertyChanged;
    protected void OnPropertyChanged(string propertyName)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

------------------ ViewModel
public class ItemsViewModel : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;

    protected void OnPropertyChanged(string propertyName)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }

    private ObservableCollection<TicketItem> _itemSignsList;
    public ObservableCollection<TicketItem> ItemSignsList
    {
        get { return _itemSignsList; }
        set { _itemSignsList = value; OnPropertyChanged("ItemSignsList"); }
    }

    public ItemsViewModel()
    {
        ItemSignsList = new ObservableCollection<TicketItem>(DataSource.GetData());
            ItemSignsList.CollectionChanged += ItemSignsList_CollectionChanged;
    }

    private void ItemSignsList_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
    {
        if (e.NewItems != null)
            foreach (TicketItem item in e.NewItems)
                item.PropertyChanged += TicketItem_PropertyChanged;

        if (e.OldItems != null)
            foreach (TicketItem item in e.OldItems)
                item.PropertyChanged -= TicketItem_PropertyChanged;
    }

    void TicketItem_PropertyChanged(object sender, PropertyChangedEventArgs e)
    {
        // Never comes here
        if (e.PropertyName == "QuantityNeeded")
        {

        }
    }
}

--------------------- Xaml.cs
public partial class ItemSignsPage : ContentPage
{
ItemsViewModel istvm;
bool IsTabLoaded { get; set; }

    public ItemSignsPage()
    {
        InitializeComponent();
    }

    protected override void OnAppearing()
    {
        base.OnAppearing();

        lvItemSigns.ItemTemplate = new DataTemplate(typeof(DataCell));
        istvm = new ItemsViewModel();
        this.BindingContext = istvm;
        lvItemSigns.ItemsSource = istvm.ItemSignsList;
    }

    class DataCell : ViewCell
    {
        public DataCell()
        {
            var grid = new Grid();
            grid.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(10, GridUnitType.Star) });
            grid.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(2, GridUnitType.Star) });

            var lblItemDesc = new Label();
            lblItemDesc.SetBinding(Label.TextProperty, "Description");
            grid.Children.Add(lblItemDesc, 0, 0);

            var entryQtyDelRet = new Entry();
            entryQtyDelRet.SetBinding(Entry.TextProperty, new Binding("QuantityNeeded", BindingMode.TwoWay));

            grid.Children.Add(entryQtyDelRet, 2, 0);

            View = grid;
        }
    }
}

Please help. If there is no way of ObservableCollection automatically updating if listview entrycell is changed then is there a way to get the value of entry which is changed preferably the object itself for that row.

Thanks,
Sai

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