title: WPF - Extend ListView with checkable AND selectable ListViewItems
body: <p>I already read many examples on extending ListViews with checkboxes bound with IsSelected. But I want something more.</p>
  
  <p>I want a seperation between the checked and selected state, so i get a ListBox that has a single selected item, but can have multiple checked items.
  Unfortunately ListViewItem does not have a property for checked and I dont see a possibility to get the ListView to work with a custom CheckableListViewItem.</p>
  
  <p>Of course i could use a List of objects with a checked property as ItemSource, but I dont think thats a good way to go. Checked or not is a matter of the list or item-container, not of the object listed in it. Beside that I dont want all my classes like user, role, group to have counterparts like checkableUser, checkableRole and checkableGroup.</p>
  
  <p>The behaviour i want can be easyly accomblished for the UI with a</p>
  
  <pre><code>&lt;DataTemplate x:Key="CheckBoxCell"&gt;
     &lt;StackPanel Orientation="Horizontal"&gt;
        &lt;CheckBox /&gt;
     &lt;/StackPanel&gt;
  &lt;/DataTemplate&gt;
  </code></pre>
  
  <p>and a </p>
  
  <pre><code>&lt;GridViewColumn CellTemplate="{StaticResource CheckBoxCell}" Width="30"/&gt;
  </code></pre>
  
  <p>But without a binding on the checkbox i cant check if it is checked or not.</p>
  
  <p>Is there any way to accomplish something like that? The perfect solution for me would be to have listView1.SelectedItem, listView1.CheckedItems and maybe a listView1.UncheckedItems and of course listView1.CheckItem and listView1.UncheckItem.</p>
  
  <p>Thanks for any help.</p>