Nested Preference Screen closes on Screenorientati

问题:

I recently stumbled upon a problem.

I am working with a Nested PreferenceScreen like this:

<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" >

<PreferenceScreen
    android:key="pref_name"
    android:title="@string/pref_title" >

</PreferenceScreen>

When my screen has the focus on the Nested Preference Screen and I change screenorientation, the Nested PreferenceScreen closes.

I have also tried including:

android:configChanges="orientation|keyboardHidden"

in AndroidManifest.xml, but didn't work.

Does anyone have a solution for this?

EDIT POSSIBLE SOLUTION:

I did find the solution. I thought it was this line:

android:configChanges="keyboardHidden|orientation|screenSize"

回答1:

Got it. In order to prevent a nested screen from closing on rotation, you need to make sure the parent screen is given a key value. Thats it. Eg:

<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" 
    android:key="useless_key">

    <PreferenceScreen
        android:key="pref_name"
        android:title="@string/pref_title" >
    </PreferenceScreen>
</PreferenceScreen>

Side note, though overriding onConfigChanges solved the issue, you should almost never do so. It completely changes how an Activity normally behaves. Rotation is just one of many reasons why a config change happens. If your Activity can't handle a rotation properly, then it'll also fail on handling those other conditions. Check out this insightful post for more.