DIalogPreference Problem

I am using preferences, and this snippet of XML always causes my application to stop unexpectly when I hit a menu settings button which is supposed to display a list of preferences. I can use CheckBoxPreference and ListPreference successfully but I cannot use DialogPreference. I cannot seem to find an example XML snippet anywhere.

I nee开发者_StackOverflow中文版d this dialog to collect a phone number in a string.

I should have been using EditTextPreference which extends DialogPreference. This works.