title: Unable to select same item twice in a CollectionView with Command NO EVENT
body: <p>I am not able to select an item twice. I don't use events. I manage everything with commands and the ViewModel.
  I can just find solutions for the Code Behind.</p>
  <p>CodeBehind Solution
  ((CollectionView)sender).SelectedItem = null;</p>
  <p>I don't use a sender, so this variant doesn't work.</p>
  <p>Here is my CommandCall:</p>
  <pre class="lang-xml prettyprint-override"><code>&lt;CollectionView SelectionMode=&quot;Single&quot;
                  ItemsSource=&quot;{Binding Source={RelativeSource AncestorType={x:Type Lib:Profile_Model}}, 
                                         Path=UserPartyById}&quot;
                  ItemTemplate=&quot;{StaticResource Profile_Party_DataTemplate}&quot;
                  SelectedItem=&quot;{Binding Source={RelativeSource AncestorType={x:Type Lib:Profile_Model}}, 
                                        Path=SelectedItem}&quot;
  
                  SelectionChangedCommand=&quot;{Binding Source={RelativeSource AncestorType={x:Type Lib:Profile_Model}}, 
                                        Path=GoPartyDetailCommand}&quot;&gt;
  
      &lt;CollectionView.ItemsLayout&gt;
          &lt;LinearItemsLayout ItemSpacing=&quot;5&quot; Orientation=&quot;Horizontal&quot; /&gt;
      &lt;/CollectionView.ItemsLayout&gt;
  
  &lt;/CollectionView&gt;
  </code></pre>
  <pre class="lang-cs prettyprint-override"><code>GoPartyDetailCommand = new Command(GoPartyDetail);
  
  private Merged_Model selectedItem;
  public Merged_Model SelectedItem
  {
      get =&gt; selectedItem;
      set =&gt; SetPorperty(ref selectedItem, value);
  }
  
  public async void GoPartyDetail()
  {
      Preferences.Set(&quot;SelectPartyId&quot;, SelectedItem.Id);
      Preferences.Set(&quot;FK_User&quot;, SelectedItem.FK_User);
      await _navigationService.NavigateToAsync&lt;PartyDetail_ViewModel&gt;();
  }
  </code></pre>
  <p>H</p>