title: Change databinding on WPF ComboBox when Checkbox value changes
body: <p>I have a WPF ComboBox which is databound to a Collection, but depending on wether a Checkbox is checked or not I'd like to vary which Collection the ComboBox is bound to.</p>
  
  <p>The basic issue is I have a large collection of MyCustomer and I also have a filtered collection of MyCustomer - the filtering is quite intensive and I don't want to do it with a CollectionView for the main reason that it is already done, the filtered collection already exists - hence the need to simply switch the databinding of the combo.</p>
  
  <p>I'm hoping for a pure XAML solution, obviously writing some code behind would be a relatively simple solutions but it doesn't feel like it should be required.</p>