New Post: mark all the options in checkcombobox checked for the initial load.

Hi,

If you want to select all the items from the ChecComboBox, you have to set its SelectedItems to the Items of the checkComboBox.
A possibility could be to listen to the Loaded event of the CheckComboBox and to set its SelectedItems at that moment :

<xctk:CheckComboBox ItemsSource="{Binding Values}"
                        Loaded="CheckComboBox_Loaded" />

 private void CheckComboBox_Loaded( object sender, RoutedEventArgs e )
    {
      var checkComboBox = sender as CheckComboBox;
      if( checkComboBox != null )
      {
        checkComboBox.SelectedItemsOverride = checkComboBox.ItemsSource as IList;
       //or
      //  foreach( var item in checkComboBox.Items )
      // {
      //    checkComboBox.SelectedItems.Add( item );
      // }
      }
    }

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