Listbox with databinding to ObservableCollection won't update UI

Question

The issue is already explained in the title. Please take a close look at the XAML and code because I'm a amateur in C# (only basic knowledge) and almost completely new to Data Binding. So here is my XAML:

<ListBox x:Name="BoardList" ItemsSource="{Binding notes, Mode=OneWay,UpdateSourceTrigger=PropertyChanged}" >
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <Grid>
                        <StackPanel Orientation="Horizontal" HorizontalAlignment="Right">
                            <TextBox IsReadOnly="True" ScrollViewer.VerticalScrollBarVisibility="Visible" Text="{Binding Text}" TextWrapping="Wrap" Foreground="DarkBlue"></TextBox>
                            <AppBarButton Visibility="{Binding visibility}" Icon="Globe" Click="OpenInBrowser" x:Name="Link"></AppBarButton>
                            <AppBarButton Icon="Copy" Click="Copy"></AppBarButton>
                            <AppBarButton Icon="Delete" Click="Delete"></AppBarButton>
                        </StackPanel>
                    </Grid>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>

Than I create an ObservableCollection in the Mainpage.xaml.cs file:

 public sealed partial class MainPage : Page
{
    ObservableCollection<BoardNote> notes = new ObservableCollection<BoardNote>();

    public MainPage()    //empty for post
    {
        this.InitializeComponent();
    }}

The class BoardNote :

 class BoardNote : NotificationObject
{

    private string _text { get; set; }
    public string Text
    {
        get { return _text; }
        set
        {
            if (_text == value) return;
            _text = value;
            RaisePropertyChanged(() => Text);
        }
    }
    public BoardNote(string text)
    {
        this._text = text ;
    }
    public Visibility visibility
    {
        get
        {
            if (_text.StartsWith("http"))
                return Visibility.Visible;
            else
                return Visibility.Collapsed;
        }
    }
}

And the Notification class:

 class NotificationObject : INotifyPropertyChanged
{
    protected void RaisePropertyChanged<T>(Expression<Func<T>> action)
    {
        var propertyName = GetPropertyName(action);
        RaisePropertyChanged(propertyName);
    }

    private static string GetPropertyName<T>(Expression<Func<T>> action)
    {
        var expression = (MemberExpression)action.Body;
        var propertyName = expression.Member.Name;
        return propertyName;
    }

    private void RaisePropertyChanged(string propertyName)
    {
        if (PropertyChanged != null)
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
    }

    public event PropertyChangedEventHandler PropertyChanged;
}

If I create a new Boardnote eg over a button the Listbox doesn't add a new item. I don't know what to do and I'm new to binding, and to the INotifyPropertyChanged class but I understand new things quickyly.

Answer 1

1.- DataContext is an instance of a class that contains the data you need. You can set the datacontext like:

    <Page xmlns:local...>
    <Page.DataContext>
      <local:ViewModelClass/>
    </Page.DataContext>    

(You can do in several ways this, as a resource and many other things)

2.- The class ViewModelClass should contain a property called Notes and must be a property.

public  ObservableCollection<BoardNote> Notes {get;} = new ObservableCollection<BoardNote>();

3.- If you need to update the data do not reinstance Notes, just clear it and readd items.

4.- It is interesting to implement INotifyPropertyChanged to make the UI refresh the View with the new data.

UPDATE:

If you set the datacontext to an Instance of Notes:

<ListBox x:Name="BoardList" ItemsSource="{Binding}">
<ListBox.DataContext>
  <local:Notes/>
 </ListBox.DataContext/>

...

But as you can see it is a bit difficult because Notes should be a class so you can inherit from ObservableCollection:

public class Notes : ObservableCollection<Note>
{
}