How to force sub PreferenceScreen to be contained in Fragment layout (Android)

Question

I'm quite new to Android's Preference system and I am currently facing a problem.

As advised by Android Guide (http://developer.android.com/guide/topics/ui/settings.html), I use Preference Fragment. Thus, my SettingsActivity contains some stuff (headers like title, tabs, etc.) and the PreferenceFragment below.

The thing is when I click on a preference associated to a "sub" PreferenceScreen, the "new preference screen" does not respect my fragment's layout but instead it fills the entire activity.

Here's an example: let's say I have a PreferenceFragment that invokes addPreferenceFromResource(R.xml.preferences). preferences.xml does contain a "Change password" preference, which is a PreferenceScreen containing 3 TextEditPreference.

preferences.xml

<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">   
    <EditTextPreference android:title="@string/pref_one"/>
    <EditTextPreference android:title="@string/pref_two"/>

    <PreferenceScreen android:title="@string/pref_change_password">

        <EditTextPreference android:title="@string/pref_current_pass"
            android:inputType="textPassword"
            android:hint="@string/hint_current_password" />

        <EditTextPreference android:title="@string/pref_new_pass"
            android:inputType="textPassword"
            android:hint="@string/hint_new_password" />

        <EditTextPreference android:title="@string/pref_confirm_new_pass"
            android:inputType="textPassword"
            android:hint="@string/hint_confirm_new_password" />

    </PreferenceScreen>
</PreferenceScreen>

So when I click on the PreferenceScreen, it does this:

But I want it to do that:

How can I do that? Thank you in advance for your answers!

Answer 1

Okay so, after a deep dive in Android Reference, I found the solution.

It appears that when a sub PreferenceScreen is clicked, a Dialog containing the new Preference objects is opened, not a new Activity or whatever.

Thus the solution is to retrieve the dialog and to make it fits into the original PreferenceFragment's layout. To do so, I used the onPreferenceTreeClick callback method to detect if a PreferenceScreen is clicked:

public class SettingsFragment extends PreferenceFragment {

    // onCreate and other stuff...

    @Override
    public boolean onPreferenceTreeClick (PreferenceScreen preferenceScreen, 
                                          Preference preference) {

        // Initiating Dialog's layout when any sub PreferenceScreen clicked
        if(preference.getClass() == PreferenceScreen.class) {
            // Retrieving the opened Dialog
            Dialog dialog = ((PreferenceScreen) preference).getDialog();
            if(dialog == null) return false;

            initDialogLayout(dialog);   // Initiate the dialog's layout
        }
        return true;
    }

    private void initDialogLayout(Dialog dialog) {
        View fragmentView = getView();

        // Get absolute coordinates of the PreferenceFragment
        int fragmentViewLocation [] = new int[2];
        fragmentView.getLocationOnScreen(fragmentViewLocation);

        // Set new dimension and position attributes of the dialog
        WindowManager.LayoutParams wlp = dialog.getWindow().getAttributes();
        wlp.x       = fragmentViewLocation[0]; // 0 for x
        wlp.y       = fragmentViewLocation[1]; // 1 for y
        wlp.width   = fragmentView.getWidth();
        wlp.height  = fragmentView.getHeight();

        dialog.getWindow().setAttributes(wlp);

        // Set flag so that you can still interact with objects outside the dialog
        dialog.getWindow().setFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL,
                                    WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL);
    }
}

And that's it, that made the trick. Please comment if you think there is a better way.