title: Datagrid itemssource is empty
body: <p>When I select itemsource from datagrid, the value is null. Is it because I did not define imtemsource in datagrid?</p>
  
  <p>This is how I add in a row into the datagrid:</p>
  
  <pre><code>this.dgProductList.Items.Add(new {ProductId=product.ProductId, Name=product.Name, Qty=1, Price=product.Price});
  </code></pre>
  
  <p>Here is my wpf:</p>
  
  
  
  <pre><code>&lt;DataGrid Name="dgProductList" 
                                    AutoGenerateColumns="False" 
                                    FontSize="15"
                                    HorizontalGridLinesBrush="#f0f0f0"
                                    VerticalGridLinesBrush="#f0f0f0"
                                    ScrollViewer.CanContentScroll="False"      
                                    ScrollViewer.VerticalScrollBarVisibility="Auto" 
                                    ScrollViewer.HorizontalScrollBarVisibility="Auto"&gt;
                              &lt;DataGrid.Columns&gt;
                                  &lt;DataGridTemplateColumn Header="Image"&gt;
                                      &lt;DataGridTemplateColumn.CellTemplate&gt;
                                          &lt;DataTemplate&gt;
                                              &lt;Image Height="10" Width="10" Source="{Binding Picture}" Stretch="Uniform"&gt;&lt;/Image&gt;
                                          &lt;/DataTemplate&gt;
                                      &lt;/DataGridTemplateColumn.CellTemplate&gt;
                                  &lt;/DataGridTemplateColumn&gt;
                                  &lt;DataGridTextColumn Binding="{Binding ProductId}" Visibility="Hidden"/&gt;
                                  &lt;DataGridTextColumn Binding="{Binding Name}" Header="Item" /&gt;
                                  &lt;DataGridTextColumn Binding="{Binding Qty}" Header="Qty" /&gt;
                                  &lt;DataGridTextColumn Binding="{Binding Price}" Header="Price" /&gt;
                                  &lt;DataGridTemplateColumn Width="*"&gt;
                                      &lt;DataGridTemplateColumn.CellTemplate&gt;
                                          &lt;DataTemplate&gt;
                                              &lt;StackPanel Orientation="Horizontal"&gt;
                                                  &lt;Button Width="30" Name="btnDecrease" Content="-" /&gt;
                                                  &lt;Button Width="30" Name="btnIncrease" Content="+" /&gt;
                                              &lt;/StackPanel&gt;
                                          &lt;/DataTemplate&gt;
                                      &lt;/DataGridTemplateColumn.CellTemplate&gt;
                                  &lt;/DataGridTemplateColumn&gt;
                              &lt;/DataGrid.Columns&gt;
                          &lt;/DataGrid&gt;
  </code></pre>