LeanbackSettingsFragment

abstract class LeanbackSettingsFragment : Fragment, PreferenceFragment.OnPreferenceStartFragmentCallback, PreferenceFragment.OnPreferenceStartScreenCallback, PreferenceFragment.OnPreferenceDisplayDialogCallback

This fragment provides a container for displaying a LeanbackPreferenceFragment

The following sample code shows a simple leanback preference fragment that is populated from a resource. The resource it loads is:

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

    <PreferenceCategory
            android:title="@string/basic_preferences">

        <Preference
                android:key="preference"
                android:title="@string/title_basic_preference"
                android:summary="@string/summary_basic_preference"/>

        <Preference
                android:key="stylized"
                android:title="@string/title_stylish_preference"
                android:summary="@string/summary_stylish_preference"/>

        <Preference
                android:key="icon"
                android:title="@string/title_icon_preference"
                android:summary="@string/summary_icon_preference"
                android:icon="@android:drawable/ic_menu_camera"/>

        <Preference
                android:key="single_line_title"
                android:title="@string/title_single_line_title_preference"
                android:summary="@string/summary_single_line_title_preference"
                app:singleLineTitle="true"/>
    </PreferenceCategory>

    <PreferenceCategory
            android:title="@string/widgets">

        <CheckBoxPreference
                android:key="checkbox"
                android:title="@string/title_checkbox_preference"
                android:summary="@string/summary_checkbox_preference"/>

        <SwitchPreferenceCompat
                android:key="switch"
                android:title="@string/title_switch_preference"
                android:summary="@string/summary_switch_preference"/>

        <DropDownPreference
                android:key="dropdown"
                android:title="@string/title_dropdown_preference"
                android:entries="@array/entries"
                app:useSimpleSummaryProvider="true"
                android:entryValues="@array/entry_values"/>

        <SeekBarPreference
                android:key="seekbar"
                android:title="@string/title_seekbar_preference"
                android:max="10"
                android:defaultValue="5"/>
    </PreferenceCategory>

    <PreferenceCategory
            android:title="@string/dialogs">

        <EditTextPreference
                android:key="edittext"
                android:title="@string/title_edittext_preference"
                app:useSimpleSummaryProvider="true"
                android:dialogTitle="@string/dialog_title_edittext_preference"/>

        <ListPreference
                android:key="list"
                android:title="@string/title_list_preference"
                app:useSimpleSummaryProvider="true"
                android:entries="@array/entries"
                android:entryValues="@array/entry_values"
                android:dialogTitle="@string/dialog_title_list_preference"/>

        <MultiSelectListPreference
                android:key="multi_select_list"
                android:title="@string/title_multi_list_preference"
                android:summary="@string/summary_multi_list_preference"
                android:entries="@array/entries"
                android:entryValues="@array/entry_values"
                android:dialogTitle="@string/dialog_title_multi_list_preference"/>
    </PreferenceCategory>

    <PreferenceCategory
            android:key="advanced"
            android:title="@string/advanced_attributes"
            app:initialExpandedChildrenCount="1">

        <Preference
                android:key="expandable"
                android:title="@string/title_expandable_preference"
                android:summary="@string/summary_expandable_preference"/>

        <Preference
                android:title="@string/title_intent_preference"
                android:summary="@string/summary_intent_preference">

            <intent android:action="android.intent.action.VIEW"
                    android:data="http://www.android.com"/>

        </Preference>

        <SwitchPreferenceCompat
                android:key="parent"
                android:title="@string/title_parent_preference"
                android:summary="@string/summary_parent_preference"/>

        <SwitchPreferenceCompat
                android:key="child"
                android:dependency="parent"
                android:title="@string/title_child_preference"
                android:summary="@string/summary_child_preference"/>

        <SwitchPreferenceCompat
                android:key="toggle_summary"
                android:title="@string/title_toggle_summary_preference"
                android:summaryOn="@string/summary_on_toggle_summary_preference"
                android:summaryOff="@string/summary_off_toggle_summary_preference"/>

        <Preference
                android:key="copyable"
                android:title="@string/title_copyable_preference"
                android:summary="@string/summary_copyable_preference"
                android:selectable="false"
                app:enableCopying="true"/>
    </PreferenceCategory>

</PreferenceScreen>

The sample implements onPreferenceStartFragment, onPreferenceStartScreen, and onPreferenceStartInitialScreen:

public static class SettingsFragment extends LeanbackSettingsFragmentCompat {
    @Override
    public void onPreferenceStartInitialScreen() {
        startPreferenceFragment(new DemoFragment());
    }

    @Override
    public boolean onPreferenceStartFragment(PreferenceFragmentCompat caller, Preference pref) {
        final Bundle args = pref.getExtras();
        final Fragment f = getChildFragmentManager().getFragmentFactory().instantiate(
                requireActivity().getClassLoader(), pref.getFragment());
        f.setArguments(args);
        f.setTargetFragment(caller, 0);
        if (f instanceof PreferenceFragmentCompat
                || f instanceof PreferenceDialogFragmentCompat) {
            startPreferenceFragment(f);
        } else {
            startImmersiveFragment(f);
        }
        return true;
    }

    @Override
    public boolean onPreferenceStartScreen(PreferenceFragmentCompat caller,
            PreferenceScreen pref) {
        final Fragment fragment = new DemoFragment();
        final Bundle args = new Bundle(1);
        args.putString(PreferenceFragmentCompat.ARG_PREFERENCE_ROOT, pref.getKey());
        fragment.setArguments(args);
        startPreferenceFragment(fragment);
        return true;
    }
}

/**
 * The fragment that is embedded in SettingsFragment
 */
public static class DemoFragment extends LeanbackPreferenceFragmentCompat {

    @Override
    public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
        // Load the preferences from an XML resource
        setPreferencesFromResource(R.xml.preferences, rootKey);
    }
}

Summary

LeanbackSettingsFragment()

fun onCreateView(
    inflater: LayoutInflater!,
    container: ViewGroup!,
    savedInstanceState: Bundle!
): View!

fun onPause(): Unit

fun onPreferenceDisplayDialog(caller: PreferenceFragment, pref: Preference!): Boolean

abstract fun onPreferenceStartInitialScreen(): Unit

fun onResume(): Unit

fun onViewCreated(view: View!, savedInstanceState: Bundle!): Unit

fun startImmersiveFragment(fragment: Fragment): Unit

fun startPreferenceFragment(fragment: Fragment): Unit