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LeanbackPreferenceFragment

public abstract class LeanbackPreferenceFragment
extends BaseLeanbackPreferenceFragment

java.lang.Object
   ↳ android.app.Fragment
     ↳ androidx.preference.PreferenceFragment
       ↳ androidx.leanback.preference.BaseLeanbackPreferenceFragment
         ↳ androidx.leanback.preference.LeanbackPreferenceFragment


This fragment provides a fully decorated leanback-style preference fragment, including a list background and header.

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

<androidx.preference.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:summary="@string/summary_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"
                app:enableCopying="true"/>
    </PreferenceCategory>

</androidx.preference.PreferenceScreen>

The fragment needs only to implement PreferenceFragment.onCreatePreferences(Bundle, String) to populate the list of preference objects:

/**
 * Entry of settings fragment.
 */
public static class SettingsFragment extends LeanbackSettingsFragmentCompat {
    @Override
    public void onPreferenceStartInitialScreen() {
        startPreferenceFragment(new PrefsFragment());
    }

    @Override
    public boolean onPreferenceStartFragment(PreferenceFragmentCompat caller, Preference pref) {
        final Bundle args = pref.getExtras();
        final Fragment f = getChildFragmentManager().getFragmentFactory().instantiate(
                requireActivity().getClassLoader(), pref.getFragment(), args);
        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 f = new PrefsFragment();
        final Bundle args = new Bundle(1);
        args.putString(PreferenceFragmentCompat.ARG_PREFERENCE_ROOT, pref.getKey());
        f.setArguments(args);
        startPreferenceFragment(f);
        return true;
    }
}

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

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

Summary

Inherited constants

Public constructors

LeanbackPreferenceFragment()

Public methods

View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
void onViewCreated(View view, Bundle savedInstanceState)
void setTitle(CharSequence title)

Set the title to be shown above the preference list

Inherited methods

Public constructors

LeanbackPreferenceFragment

public LeanbackPreferenceFragment ()

Public methods

onCreateView

public View onCreateView (LayoutInflater inflater, 
                ViewGroup container, 
                Bundle savedInstanceState)

Parameters
inflater LayoutInflater

container ViewGroup

savedInstanceState Bundle

Returns
View

onViewCreated

public void onViewCreated (View view, 
                Bundle savedInstanceState)

Parameters
view View

savedInstanceState Bundle

setTitle

public void setTitle (CharSequence title)

Set the title to be shown above the preference list

Parameters
title CharSequence: Title text to be shown