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POWPF Databinding with object source fails to update
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  1. POWPF Databinding with object source fails to update
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    copied!<p>I have been struggling a while with this problem and read a lot but most of the examples are too simple. I am trying to bind a very simple ObservableCollection to a DataGrid. The super simple objects within the Collection are "SingleItems" which are defined like this:</p> <pre><code>public class SingleItem { private String _name=null; public String Name { get { return _name; } set { _name=value; } } public SingleItem(String name) { Name=name; } </code></pre> <p>The class ManyItems hosts the Collection and is defined like this:</p> <pre><code>public class ManyItems{ private ObservableCollection&lt;SingleItem&gt; allItems=new ObservableCollection&lt;SingleItem&gt;(); public ManyItems() { AllItems.Add(new SingleItem("inside"));//debug code } public ObservableCollection&lt;SingleItem&gt; AllItems { get { return allItems; } set { allItems=value; } } public void AddItem(SingleItem item) { AllItems.Add(item); } } </code></pre> <p>In my main window I just want to update ManyItems when the user presses a button:</p> <pre><code>public partial class MainWindow : Window{ int count=0; ManyItems _items=new ManyItems(); public ManyItems Items { get { return _items; } set { _items=value; } } public MainWindow(){ this.InitializeComponent(); } private void Button_Click(object sender, System.Windows.RoutedEventArgs e){ Items.AddItem(new SingleItem("name_"+count)); count++; } </code></pre> <p>}</p> <p>Finally my XAML looks like this (shortened where "..."):</p> <pre><code>&lt;Window ... xmlns:local="clr-namespace:DataGridTEst" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:XamlGeneratedNamespace="clr-namespace:XamlGeneratedNamespace" mc:Ignorable="d" x:Class="DataGridTEst.MainWindow" x:Name="Window" Title="MainWindow" Width="640" Height="480"&gt; &lt;Window.Resources&gt; &lt;local:ManyItems x:Key="ManyItemsDataSource" d:IsDataSource="True"/&gt; &lt;/Window.Resources&gt; &lt;Grid x:Name="LayoutRoot" DataContext="{Binding Source={StaticResource ManyItemsDataSource}}"&gt; &lt;Button Content="Button" .... Click="Button_Click"/&gt; &lt;DataGrid ... ItemsSource="{Binding AllItems}"/&gt; &lt;/Grid&gt; </code></pre> <p></p> <p>When I run this app, the grid shows the SingleItem "inside" which I created in the constructor. However no changes to the underlying Collections are reflected in the datagrid. I tried also to use INotifyPropertyChanged but without success. I think I have a grave error in my understanding. Can anybody explain me what I am doing wrong? Also online examples (where not everything is done inside constructors) are greatly appreciated.</p> <p>Thanks for your help, Sebastian</p>
 

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