Preference sub-screen not opening when using support.v7.preference

Question

I am trying to implement preferences with sub-screens using AppCompatActivity and support.v7.preference

According to the docs, every PreferenceScreen within another

Answer 1

One extremely important thing you need you remember:

Your PreferenceScreen must contain :

android:key="name_a_unique_key"

Otherwise, it will not work. I've spent hours with thí