as it is possible in the combobox wpf to eliminate the search in all the letters of the list and if possible to type a word that it is not present in the list
Hello,
It has been a while since you have made your post, in case you still need support I will be glad to assist you further. I suppose the other community members can benefit from this answer as well. So I have been looking through your post and if I understands you correct you want to be able to set Value for the XamComboEditor not only from the dropdown list. If so, I can suggest you set the IsEditable property of the XamComboEditor to True in order to type in the it. If the value you entered is not in the ItemsSource it will still be set as Value of the editor.
Feel free to write me if you have any other questions.