Use Drawer in Settings app

- get rid of PreferenceActivity as much as we can and use fragments instead
- add Drawer widget
- add Dashboard high level entry into the Drawer (but this is work in progress and would be done in another CL)
- add bypass of fragment's Header  validation when launched from the Drawer but *force* validation if external
call thru an Intent

Be aware that WifiPickerActivity should remain for now a PreferenceActivity. It is used by SetupWizard and should
not trigger running the SettingsActivity's header building code. SetupWizard is a Home during the provisionnig process
and then deactivate itself as a Home but would make the Home header to appear in the Drawer (because momentarily we
would have two Home).

Also, verified that:

- the WiFi settings still work when called from SetupWizard
- when you have multiple Launchers, the Home header will appear in the list of Headers in the Drawer

Change-Id: I407a5e0fdd843ad7615d3d511c416a44e3d97c90

1 files changed, 1770 insertions, 0 deletions

diff --git a/src/com/android/settings/SettingsActivity.java b/src/com/android/settings/SettingsActivity.java
new file mode 100644
index 000000000..c3d067f73
--- /dev/null
+++ b/src/com/android/settings/SettingsActivity.java
@@ -0,0 +1,1770 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings;
+
+import android.accounts.Account;
+import android.accounts.AccountManager;
+import android.accounts.OnAccountsUpdateListener;
+import android.app.ActionBar;
+import android.app.Activity;
+import android.app.Fragment;
+import android.app.FragmentManager;
+import android.app.FragmentTransaction;
+import android.app.AlertDialog;
+import android.app.Dialog;
+import android.app.DialogFragment;
+import android.app.admin.DevicePolicyManager;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.content.SharedPreferences;
+import android.content.pm.ActivityInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.PackageManager.NameNotFoundException;
+import android.content.pm.ResolveInfo;
+import android.content.res.Configuration;
+import android.content.res.Resources;
+import android.content.res.TypedArray;
+import android.content.res.XmlResourceParser;
+import android.graphics.drawable.Drawable;
+import android.nfc.NfcAdapter;
+import android.os.Bundle;
+import android.os.Handler;
+import android.os.INetworkManagementService;
+import android.os.Message;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.os.RemoteException;
+import android.os.ServiceManager;
+import android.os.UserHandle;
+import android.os.UserManager;
+import android.preference.Preference;
+import android.preference.PreferenceFragment;
+import android.preference.PreferenceManager;
+import android.preference.PreferenceScreen;
+import android.support.v4.app.ActionBarDrawerToggle;
+import android.support.v4.widget.DrawerLayout;
+import android.text.TextUtils;
+import android.util.AttributeSet;
+import android.util.Log;
+import android.util.Pair;
+import android.util.TypedValue;
+import android.util.Xml;
+import android.view.LayoutInflater;
+import android.view.MenuItem;
+import android.view.View;
+import android.view.View.OnClickListener;
+import android.view.ViewGroup;
+import android.widget.AbsListView;
+import android.widget.AdapterView;
+import android.widget.ArrayAdapter;
+import android.widget.Button;
+import android.widget.ImageButton;
+import android.widget.ImageView;
+import android.widget.ListView;
+import android.widget.Switch;
+import android.widget.TextView;
+
+import com.android.internal.util.ArrayUtils;
+import com.android.internal.util.XmlUtils;
+import com.android.settings.accessibility.AccessibilitySettings;
+import com.android.settings.accessibility.CaptionPropertiesFragment;
+import com.android.settings.accounts.AccountSyncSettings;
+import com.android.settings.accounts.AuthenticatorHelper;
+import com.android.settings.accounts.ChooseAccountFragment;
+import com.android.settings.accounts.ManageAccountsSettings;
+import com.android.settings.applications.ManageApplications;
+import com.android.settings.applications.ProcessStatsUi;
+import com.android.settings.bluetooth.BluetoothEnabler;
+import com.android.settings.bluetooth.BluetoothSettings;
+import com.android.settings.dashboard.DashboardSummary;
+import com.android.settings.deviceinfo.Memory;
+import com.android.settings.deviceinfo.UsbSettings;
+import com.android.settings.fuelgauge.PowerUsageSummary;
+import com.android.settings.inputmethod.InputMethodAndLanguageSettings;
+import com.android.settings.inputmethod.KeyboardLayoutPickerFragment;
+import com.android.settings.inputmethod.SpellCheckersSettings;
+import com.android.settings.inputmethod.UserDictionaryList;
+import com.android.settings.location.LocationSettings;
+import com.android.settings.nfc.AndroidBeam;
+import com.android.settings.nfc.PaymentSettings;
+import com.android.settings.print.PrintJobSettingsFragment;
+import com.android.settings.print.PrintSettingsFragment;
+import com.android.settings.tts.TextToSpeechSettings;
+import com.android.settings.users.UserSettings;
+import com.android.settings.vpn2.VpnSettings;
+import com.android.settings.wfd.WifiDisplaySettings;
+import com.android.settings.wifi.AdvancedWifiSettings;
+import com.android.settings.wifi.WifiEnabler;
+import com.android.settings.wifi.WifiSettings;
+import com.android.settings.wifi.p2p.WifiP2pSettings;
+import org.xmlpull.v1.XmlPullParser;
+import org.xmlpull.v1.XmlPullParserException;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.HashMap;
+import java.util.List;
+
+public class SettingsActivity extends Activity
+        implements PreferenceManager.OnPreferenceTreeClickListener,
+        PreferenceFragment.OnPreferenceStartFragmentCallback,
+        ButtonBarHandler, OnAccountsUpdateListener, FragmentManager.OnBackStackChangedListener {
+
+    private static final String LOG_TAG = "Settings";
+
+    // Constants for state save/restore
+    private static final String HEADERS_TAG = ":settings:headers";
+    private static final String CUR_HEADER_TAG = ":settings:cur_header";
+
+    /**
+     * When starting this activity, the invoking Intent can contain this extra
+     * string to specify which fragment should be initially displayed.
+     * <p/>Starting from Key Lime Pie, when this argument is passed in, the activity
+     * will call isValidFragment() to confirm that the fragment class name is valid for this
+     * activity.
+     */
+    public static final String EXTRA_SHOW_FRAGMENT = ":settings:show_fragment";
+
+    /**
+     * When starting this activity and using {@link #EXTRA_SHOW_FRAGMENT},
+     * this extra can also be specified to supply a Bundle of arguments to pass
+     * to that fragment when it is instantiated during the initial creation
+     * of the activity.
+     */
+    public static final String EXTRA_SHOW_FRAGMENT_ARGUMENTS = ":settings:show_fragment_args";
+
+    /**
+     * When starting this activity, the invoking Intent can contain this extra
+     * boolean that the header list should not be displayed.  This is most often
+     * used in conjunction with {@link #EXTRA_SHOW_FRAGMENT} to launch
+     * the activity to display a specific fragment that the user has navigated
+     * to.
+     */
+    public static final String EXTRA_NO_HEADERS = ":settings:no_headers";
+
+    // extras that allow any preference activity to be launched as part of a wizard
+
+    // show Back and Next buttons? takes boolean parameter
+    // Back will then return RESULT_CANCELED and Next RESULT_OK
+    protected static final String EXTRA_PREFS_SHOW_BUTTON_BAR = "extra_prefs_show_button_bar";
+
+    // add a Skip button?
+    private static final String EXTRA_PREFS_SHOW_SKIP = "extra_prefs_show_skip";
+
+    // specify custom text for the Back or Next buttons, or cause a button to not appear
+    // at all by setting it to null
+    protected static final String EXTRA_PREFS_SET_NEXT_TEXT = "extra_prefs_set_next_text";
+    protected static final String EXTRA_PREFS_SET_BACK_TEXT = "extra_prefs_set_back_text";
+
+    /**
+     * When starting this activity and using {@link #EXTRA_SHOW_FRAGMENT},
+     * this extra can also be specify to supply the title to be shown for
+     * that fragment.
+     */
+    protected static final String EXTRA_SHOW_FRAGMENT_TITLE = ":settings:show_fragment_title";
+
+    private static final String BACK_STACK_PREFS = ":settings:prefs";
+
+    private static final String META_DATA_KEY_HEADER_ID =
+        "com.android.settings.TOP_LEVEL_HEADER_ID";
+
+    private static final String META_DATA_KEY_FRAGMENT_CLASS =
+        "com.android.settings.FRAGMENT_CLASS";
+
+    private static final String EXTRA_UI_OPTIONS = "settings:ui_options";
+
+    private static final String SAVE_KEY_CURRENT_HEADER = "com.android.settings.CURRENT_HEADER";
+
+    private static boolean sShowNoHomeNotice = false;
+
+    private String mFragmentClass;
+    private int mTopLevelHeaderId;
+    private Header mFirstHeader;
+    private Header mCurrentHeader;
+
+    // Show only these settings for restricted users
+    private int[] SETTINGS_FOR_RESTRICTED = {
+            R.id.wireless_section,
+            R.id.wifi_settings,
+            R.id.bluetooth_settings,
+            R.id.data_usage_settings,
+            R.id.wireless_settings,
+            R.id.device_section,
+            R.id.sound_settings,
+            R.id.display_settings,
+            R.id.storage_settings,
+            R.id.application_settings,
+            R.id.battery_settings,
+            R.id.personal_section,
+            R.id.location_settings,
+            R.id.security_settings,
+            R.id.language_settings,
+            R.id.user_settings,
+            R.id.account_settings,
+            R.id.account_add,
+            R.id.system_section,
+            R.id.date_time_settings,
+            R.id.about_settings,
+            R.id.accessibility_settings,
+            R.id.print_settings,
+            R.id.nfc_payment_settings,
+            R.id.home_settings
+    };
+
+    private static final String[] ENTRY_FRAGMENTS = {
+            WirelessSettings.class.getName(),
+            WifiSettings.class.getName(),
+            AdvancedWifiSettings.class.getName(),
+            BluetoothSettings.class.getName(),
+            TetherSettings.class.getName(),
+            WifiP2pSettings.class.getName(),
+            VpnSettings.class.getName(),
+            DateTimeSettings.class.getName(),
+            LocalePicker.class.getName(),
+            InputMethodAndLanguageSettings.class.getName(),
+            SpellCheckersSettings.class.getName(),
+            UserDictionaryList.class.getName(),
+            UserDictionarySettings.class.getName(),
+            SoundSettings.class.getName(),
+            DisplaySettings.class.getName(),
+            DeviceInfoSettings.class.getName(),
+            ManageApplications.class.getName(),
+            ProcessStatsUi.class.getName(),
+            NotificationStation.class.getName(),
+            LocationSettings.class.getName(),
+            SecuritySettings.class.getName(),
+            PrivacySettings.class.getName(),
+            DeviceAdminSettings.class.getName(),
+            AccessibilitySettings.class.getName(),
+            CaptionPropertiesFragment.class.getName(),
+            com.android.settings.accessibility.ToggleInversionPreferenceFragment.class.getName(),
+            com.android.settings.accessibility.ToggleContrastPreferenceFragment.class.getName(),
+            com.android.settings.accessibility.ToggleDaltonizerPreferenceFragment.class.getName(),
+            TextToSpeechSettings.class.getName(),
+            Memory.class.getName(),
+            DevelopmentSettings.class.getName(),
+            UsbSettings.class.getName(),
+            AndroidBeam.class.getName(),
+            WifiDisplaySettings.class.getName(),
+            PowerUsageSummary.class.getName(),
+            AccountSyncSettings.class.getName(),
+            CryptKeeperSettings.class.getName(),
+            DataUsageSummary.class.getName(),
+            DreamSettings.class.getName(),
+            UserSettings.class.getName(),
+            NotificationAccessSettings.class.getName(),
+            ManageAccountsSettings.class.getName(),
+            PrintSettingsFragment.class.getName(),
+            PrintJobSettingsFragment.class.getName(),
+            TrustedCredentialsSettings.class.getName(),
+            PaymentSettings.class.getName(),
+            KeyboardLayoutPickerFragment.class.getName(),
+            ChooseAccountFragment.class.getName(),
+            DashboardSummary.class.getName()
+    };
+
+    private SharedPreferences mDevelopmentPreferences;
+    private SharedPreferences.OnSharedPreferenceChangeListener mDevelopmentPreferencesListener;
+
+    // TODO: Update Call Settings based on airplane mode state.
+
+    protected HashMap<Integer, Integer> mHeaderIndexMap = new HashMap<Integer, Integer>();
+
+    private AuthenticatorHelper mAuthenticatorHelper;
+    private boolean mListeningToAccountUpdates;
+
+    private Button mNextButton;
+
+    private boolean mBatteryPresent = true;
+    private BroadcastReceiver mBatteryInfoReceiver = new BroadcastReceiver() {
+
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            String action = intent.getAction();
+            if (Intent.ACTION_BATTERY_CHANGED.equals(action)) {
+                boolean batteryPresent = Utils.isBatteryPresent(intent);
+
+                if (mBatteryPresent != batteryPresent) {
+                    mBatteryPresent = batteryPresent;
+                    invalidateHeaders();
+                }
+            }
+        }
+    };
+
+    private final ArrayList<Header> mHeaders = new ArrayList<Header>();
+    private Header mCurHeader;
+    private HeaderAdapter mHeaderAdapter;
+
+    private class TitlePair extends Pair<Integer, CharSequence> {
+
+        public TitlePair(Integer first, CharSequence second) {
+            super(first, second);
+        }
+    }
+
+    private final ArrayList<TitlePair> mTitleStack = new ArrayList<TitlePair>();
+
+    private DrawerLayout mDrawerLayout;
+    private ListView mDrawer;
+    private ActionBarDrawerToggle mDrawerToggle;
+    private ActionBar mActionBar;
+
+    private static final int MSG_BUILD_HEADERS = 1;
+    private Handler mHandler = new Handler() {
+        @Override
+        public void handleMessage(Message msg) {
+            switch (msg.what) {
+                case MSG_BUILD_HEADERS: {
+                    mHeaders.clear();
+                    onBuildHeaders(mHeaders);
+                    mHeaderAdapter.notifyDataSetChanged();
+                    if (mCurHeader != null) {
+                        Header mappedHeader = findBestMatchingHeader(mCurHeader, mHeaders);
+                        if (mappedHeader != null) {
+                            setSelectedHeader(mappedHeader);
+                        }
+                    }
+                } break;
+            }
+        }
+    };
+
+    @Override
+    public boolean onPreferenceStartFragment(PreferenceFragment caller, Preference pref) {
+        // Override the fragment title for Wallpaper settings
+        int titleRes = pref.getTitleRes();
+        if (pref.getFragment().equals(WallpaperTypeSettings.class.getName())) {
+            titleRes = R.string.wallpaper_settings_fragment_title;
+        } else if (pref.getFragment().equals(OwnerInfoSettings.class.getName())
+                && UserHandle.myUserId() != UserHandle.USER_OWNER) {
+            if (UserManager.get(this).isLinkedUser()) {
+                titleRes = R.string.profile_info_settings_title;
+            } else {
+                titleRes = R.string.user_info_settings_title;
+            }
+        }
+        startPreferencePanel(pref.getFragment(), pref.getExtras(), titleRes, pref.getTitle(),
+                null, 0);
+        return true;
+    }
+
+    @Override
+    public boolean onPreferenceTreeClick(PreferenceScreen preferenceScreen, Preference preference) {
+        return false;
+    }
+
+    private class DrawerListener implements DrawerLayout.DrawerListener {
+        @Override
+        public void onDrawerOpened(View drawerView) {
+            mDrawerToggle.onDrawerOpened(drawerView);
+        }
+
+        @Override
+        public void onDrawerClosed(View drawerView) {
+            mDrawerToggle.onDrawerClosed(drawerView);
+            onHeaderClick(mCurrentHeader);
+        }
+
+        @Override
+        public void onDrawerSlide(View drawerView, float slideOffset) {
+            mDrawerToggle.onDrawerSlide(drawerView, slideOffset);
+        }
+
+        @Override
+        public void onDrawerStateChanged(int newState) {
+            mDrawerToggle.onDrawerStateChanged(newState);
+        }
+    }
+
+    private class DrawerItemClickListener implements ListView.OnItemClickListener {
+        @Override
+        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
+            mDrawerLayout.closeDrawer(mDrawer);
+            onListItemClick((ListView)parent, view, position, id);
+        }
+    }
+
+    private Header findBestMatchingHeader(Header cur, ArrayList<Header> from) {
+        ArrayList<Header> matches = new ArrayList<Header>();
+        for (int j=0; j<from.size(); j++) {
+            Header oh = from.get(j);
+            if (cur == oh || (cur.id != HEADER_ID_UNDEFINED && cur.id == oh.id)) {
+                // Must be this one.
+                matches.clear();
+                matches.add(oh);
+                break;
+            }
+            if (cur.fragment != null) {
+                if (cur.fragment.equals(oh.fragment)) {
+                    matches.add(oh);
+                }
+            } else if (cur.intent != null) {
+                if (cur.intent.equals(oh.intent)) {
+                    matches.add(oh);
+                }
+            } else if (cur.title != null) {
+                if (cur.title.equals(oh.title)) {
+                    matches.add(oh);
+                }
+            }
+        }
+        final int NM = matches.size();
+        if (NM == 1) {
+            return matches.get(0);
+        } else if (NM > 1) {
+            for (int j=0; j<NM; j++) {
+                Header oh = matches.get(j);
+                if (cur.fragmentArguments != null &&
+                        cur.fragmentArguments.equals(oh.fragmentArguments)) {
+                    return oh;
+                }
+                if (cur.extras != null && cur.extras.equals(oh.extras)) {
+                    return oh;
+                }
+                if (cur.title != null && cur.title.equals(oh.title)) {
+                    return oh;
+                }
+            }
+        }
+        return null;
+    }
+
+    private void invalidateHeaders() {
+        if (!mHandler.hasMessages(MSG_BUILD_HEADERS)) {
+            mHandler.sendEmptyMessage(MSG_BUILD_HEADERS);
+        }
+    }
+
+    @Override
+    protected void onPostCreate(Bundle savedInstanceState) {
+        super.onPostCreate(savedInstanceState);
+
+        // Sync the toggle state after onRestoreInstanceState has occurred.
+        if (mDrawerToggle != null) {
+            mDrawerToggle.syncState();
+        }
+    }
+
+    @Override
+    public void onConfigurationChanged(Configuration newConfig) {
+        super.onConfigurationChanged(newConfig);
+        if (mDrawerToggle != null) {
+            mDrawerToggle.onConfigurationChanged(newConfig);
+        }
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        if (mDrawerToggle != null && mDrawerToggle.onOptionsItemSelected(item)) {
+            return true;
+        }
+        return super.onOptionsItemSelected(item);
+    }
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        if (getIntent().hasExtra(EXTRA_UI_OPTIONS)) {
+            getWindow().setUiOptions(getIntent().getIntExtra(EXTRA_UI_OPTIONS, 0));
+        }
+
+        mAuthenticatorHelper = new AuthenticatorHelper();
+        mAuthenticatorHelper.updateAuthDescriptions(this);
+        mAuthenticatorHelper.onAccountsUpdated(this, null);
+
+        DevicePolicyManager dpm =
+                (DevicePolicyManager) getSystemService(Context.DEVICE_POLICY_SERVICE);
+        mHeaderAdapter= new HeaderAdapter(this, getHeaders(), mAuthenticatorHelper, dpm);
+
+        mDevelopmentPreferences = getSharedPreferences(DevelopmentSettings.PREF_FILE,
+                Context.MODE_PRIVATE);
+
+        getMetaData();
+
+        super.onCreate(savedInstanceState);
+
+        setContentView(R.layout.settings_main);
+
+        getFragmentManager().addOnBackStackChangedListener(this);
+
+        mActionBar = getActionBar();
+        if (mActionBar != null) {
+            mActionBar.setDisplayHomeAsUpEnabled(true);
+            mActionBar.setHomeButtonEnabled(true);
+
+            mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
+            mDrawerLayout.setDrawerListener(new DrawerListener());
+
+            mDrawer = (ListView) findViewById(R.id.headers_drawer);
+            mDrawer.setAdapter(mHeaderAdapter);
+            mDrawer.setOnItemClickListener(new DrawerItemClickListener());
+            mDrawer.setChoiceMode(AbsListView.CHOICE_MODE_SINGLE);
+
+            mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
+                    R.drawable.ic_drawer, R.string.drawer_open, R.string.drawer_close);
+        }
+
+        String initialFragment = getIntent().getStringExtra(EXTRA_SHOW_FRAGMENT);
+        Bundle initialArguments = getIntent().getBundleExtra(EXTRA_SHOW_FRAGMENT_ARGUMENTS);
+
+        if (savedInstanceState != null) {
+            // We are restarting from a previous saved state; used that to
+            // initialize, instead of starting fresh.
+            ArrayList<Header> headers = savedInstanceState.getParcelableArrayList(HEADERS_TAG);
+            if (headers != null) {
+                mHeaders.addAll(headers);
+                int curHeader = savedInstanceState.getInt(CUR_HEADER_TAG,
+                        (int) HEADER_ID_UNDEFINED);
+                if (curHeader >= 0 && curHeader < mHeaders.size()) {
+                    setSelectedHeader(mHeaders.get(curHeader));
+                }
+            }
+
+        } else {
+            if (initialFragment != null) {
+                // If we are just showing a fragment, we want to run in
+                // new fragment mode, but don't need to compute and show
+                // the headers.
+                switchToHeader(initialFragment, initialArguments, true);
+
+                final int initialTitle = getIntent().getIntExtra(EXTRA_SHOW_FRAGMENT_TITLE, 0);
+                if (initialTitle != 0) {
+                    setTitle(getText(initialTitle));
+                }
+            } else {
+                // We need to try to build the headers.
+                onBuildHeaders(mHeaders);
+
+                // If there are headers, then at this point we need to show
+                // them and, depending on the screen, we may also show in-line
+                // the currently selected preference fragment.
+                if (mHeaders.size() > 0) {
+                    if (initialFragment == null) {
+                        Header h = onGetInitialHeader();
+                        switchToHeader(h, false);
+                    } else {
+                        switchToHeader(initialFragment, initialArguments, false);
+                    }
+                }
+            }
+        }
+
+        // see if we should show Back/Next buttons
+        Intent intent = getIntent();
+        if (intent.getBooleanExtra(EXTRA_PREFS_SHOW_BUTTON_BAR, false)) {
+
+            View buttonBar = findViewById(com.android.internal.R.id.button_bar);
+            if (buttonBar != null) {
+                buttonBar.setVisibility(View.VISIBLE);
+
+                Button backButton = (Button)findViewById(com.android.internal.R.id.back_button);
+                backButton.setOnClickListener(new OnClickListener() {
+                    public void onClick(View v) {
+                        setResult(RESULT_CANCELED);
+                        finish();
+                    }
+                });
+                Button skipButton = (Button)findViewById(com.android.internal.R.id.skip_button);
+                skipButton.setOnClickListener(new OnClickListener() {
+                    public void onClick(View v) {
+                        setResult(RESULT_OK);
+                        finish();
+                    }
+                });
+                mNextButton = (Button)findViewById(com.android.internal.R.id.next_button);
+                mNextButton.setOnClickListener(new OnClickListener() {
+                    public void onClick(View v) {
+                        setResult(RESULT_OK);
+                        finish();
+                    }
+                });
+
+                // set our various button parameters
+                if (intent.hasExtra(EXTRA_PREFS_SET_NEXT_TEXT)) {
+                    String buttonText = intent.getStringExtra(EXTRA_PREFS_SET_NEXT_TEXT);
+                    if (TextUtils.isEmpty(buttonText)) {
+                        mNextButton.setVisibility(View.GONE);
+                    }
+                    else {
+                        mNextButton.setText(buttonText);
+                    }
+                }
+                if (intent.hasExtra(EXTRA_PREFS_SET_BACK_TEXT)) {
+                    String buttonText = intent.getStringExtra(EXTRA_PREFS_SET_BACK_TEXT);
+                    if (TextUtils.isEmpty(buttonText)) {
+                        backButton.setVisibility(View.GONE);
+                    }
+                    else {
+                        backButton.setText(buttonText);
+                    }
+                }
+                if (intent.getBooleanExtra(EXTRA_PREFS_SHOW_SKIP, false)) {
+                    skipButton.setVisibility(View.VISIBLE);
+                }
+            }
+        }
+
+        if (!onIsHidingHeaders()) {
+            highlightHeader(mTopLevelHeaderId);
+        }
+
+        // Retrieve any saved state
+        if (savedInstanceState != null) {
+            mCurrentHeader = savedInstanceState.getParcelable(SAVE_KEY_CURRENT_HEADER);
+        }
+    }
+
+    @Override
+    public void onBackStackChanged() {
+        final int count = getFragmentManager().getBackStackEntryCount() + 1;
+        TitlePair pair = null;
+        int last;
+        while (mTitleStack.size() > count) {
+            last = mTitleStack.size() - 1;
+            pair = mTitleStack.remove(last);
+        }
+        // Check if we go back
+        if (pair != null) {
+            int size = mTitleStack.size();
+            if (size > 0) {
+                last = mTitleStack.size() - 1;
+                pair = mTitleStack.get(last);
+                if (pair != null) {
+                    final CharSequence title;
+                    if (pair.first > 0) {
+                        title = getText(pair.first);
+                    } else {
+                        title = pair.second;
+                    }
+                    setTitle(title);
+                }
+            }
+        }
+    }
+
+    /**
+     * Returns the Header list
+     */
+    private List<Header> getHeaders() {
+        return mHeaders;
+    }
+
+    @Override
+    protected void onSaveInstanceState(Bundle outState) {
+        super.onSaveInstanceState(outState);
+
+        if (mHeaders.size() > 0) {
+            outState.putParcelableArrayList(HEADERS_TAG, mHeaders);
+            if (mCurHeader != null) {
+                int index = mHeaders.indexOf(mCurHeader);
+                if (index >= 0) {
+                    outState.putInt(CUR_HEADER_TAG, index);
+                }
+            }
+        }
+
+        // Save the current fragment, if it is the same as originally launched
+        if (mCurrentHeader != null) {
+            outState.putParcelable(SAVE_KEY_CURRENT_HEADER, mCurrentHeader);
+        }
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+
+        mDevelopmentPreferencesListener = new SharedPreferences.OnSharedPreferenceChangeListener() {
+            @Override
+            public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
+                invalidateHeaders();
+            }
+        };
+        mDevelopmentPreferences.registerOnSharedPreferenceChangeListener(
+                mDevelopmentPreferencesListener);
+
+        mHeaderAdapter.resume();
+        invalidateHeaders();
+
+        registerReceiver(mBatteryInfoReceiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+
+        unregisterReceiver(mBatteryInfoReceiver);
+
+        mHeaderAdapter.pause();
+
+        mDevelopmentPreferences.unregisterOnSharedPreferenceChangeListener(
+                mDevelopmentPreferencesListener);
+
+        mDevelopmentPreferencesListener = null;
+    }
+
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        if (mListeningToAccountUpdates) {
+            AccountManager.get(this).removeOnAccountsUpdatedListener(this);
+        }
+    }
+
+    /**
+     * @hide
+     */
+    protected boolean isValidFragment(String fragmentName) {
+        // Almost all fragments are wrapped in this,
+        // except for a few that have their own activities.
+        for (int i = 0; i < ENTRY_FRAGMENTS.length; i++) {
+            if (ENTRY_FRAGMENTS[i].equals(fragmentName)) return true;
+        }
+        return false;
+    }
+
+    /**
+     * When in two-pane mode, switch to the fragment pane to show the given
+     * preference fragment.
+     *
+     * @param header The new header to display.
+     * @param validate true means that the fragment's Header needs to be validated
+     */
+    private void switchToHeader(Header header, boolean validate) {
+        if (mCurHeader == header) {
+            // This is the header we are currently displaying.  Just make sure
+            // to pop the stack up to its root state.
+            getFragmentManager().popBackStack(BACK_STACK_PREFS,
+                    FragmentManager.POP_BACK_STACK_INCLUSIVE);
+        } else {
+            mTitleStack.clear();
+            if (header.fragment == null) {
+                throw new IllegalStateException("can't switch to header that has no fragment");
+            }
+            switchToHeaderInner(header.fragment, header.fragmentArguments, validate);
+            setSelectedHeader(header);
+            final CharSequence title;
+            if (header.fragment.equals("com.android.settings.dashboard.DashboardSummary")) {
+                title = getResources().getString(R.string.settings_label);
+            } else {
+                title = header.getTitle(getResources());
+            }
+            final TitlePair pair = new TitlePair(0, title);
+            mTitleStack.add(pair);
+            setTitle(title);
+        }
+    }
+
+    private void setSelectedHeader(Header header) {
+        mCurHeader = header;
+        int index = mHeaders.indexOf(header);
+        if (mDrawer != null) {
+            if (index >= 0) {
+                mDrawer.setItemChecked(index, true);
+            } else {
+                mDrawer.clearChoices();
+            }
+        }
+    }
+
+    public Header onGetInitialHeader() {
+        String fragmentClass = getStartingFragmentClass(super.getIntent());
+        if (fragmentClass != null) {
+            Header header = new Header();
+            header.fragment = fragmentClass;
+            header.title = getTitle();
+            header.fragmentArguments = getIntent().getExtras();
+            mCurrentHeader = header;
+            return header;
+        }
+
+        return mFirstHeader;
+    }
+
+    /**
+     * When in two-pane mode, switch the fragment pane to show the given
+     * preference fragment.
+     *
+     * @param fragmentName The name of the fragment to display.
+     * @param args Optional arguments to supply to the fragment.
+     * @param validate true means that the fragment's Header needs to be validated
+     */
+    private void switchToHeader(String fragmentName, Bundle args, boolean validate) {
+        setSelectedHeader(null);
+        switchToHeaderInner(fragmentName, args, validate);
+    }
+
+    private void switchToHeaderInner(String fragmentName, Bundle args, boolean validate) {
+        getFragmentManager().popBackStack(BACK_STACK_PREFS,
+                FragmentManager.POP_BACK_STACK_INCLUSIVE);
+        if (validate && !isValidFragment(fragmentName)) {
+            throw new IllegalArgumentException("Invalid fragment for this activity: "
+                    + fragmentName);
+        }
+        Fragment f = Fragment.instantiate(this, fragmentName, args);
+        FragmentTransaction transaction = getFragmentManager().beginTransaction();
+        transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
+        transaction.replace(R.id.prefs, f);
+        transaction.commitAllowingStateLoss();
+    }
+
+    @Override
+    public void onNewIntent(Intent intent) {
+        super.onNewIntent(intent);
+
+        // If it is not launched from history, then reset to top-level
+        if ((intent.getFlags() & Intent.FLAG_ACTIVITY_LAUNCHED_FROM_HISTORY) == 0) {
+            if (mDrawer != null) {
+                mDrawer.setSelectionFromTop(0, 0);
+            }
+        }
+    }
+
+    /**
+     * Called to determine whether the header list should be hidden.
+     * The default implementation returns the
+     * value given in {@link #EXTRA_NO_HEADERS} or false if it is not supplied.
+     * This is set to false, for example, when the activity is being re-launched
+     * to show a particular preference activity.
+     */
+    public boolean onIsHidingHeaders() {
+        return getIntent().getBooleanExtra(EXTRA_NO_HEADERS, false);
+    }
+
+    private void highlightHeader(int id) {
+        if (id != 0) {
+            Integer index = mHeaderIndexMap.get(id);
+            if (index != null && mDrawer != null) {
+                mDrawer.setItemChecked(index, true);
+                if (mDrawer.getVisibility() == View.VISIBLE) {
+                    mDrawer.smoothScrollToPosition(index);
+                }
+            }
+        }
+    }
+
+    @Override
+    public Intent getIntent() {
+        Intent superIntent = super.getIntent();
+        String startingFragment = getStartingFragmentClass(superIntent);
+        // This is called from super.onCreate, isMultiPane() is not yet reliable
+        // Do not use onIsHidingHeaders either, which relies itself on this method
+        if (startingFragment != null) {
+            Intent modIntent = new Intent(superIntent);
+            modIntent.putExtra(EXTRA_SHOW_FRAGMENT, startingFragment);
+            Bundle args = superIntent.getExtras();
+            if (args != null) {
+                args = new Bundle(args);
+            } else {
+                args = new Bundle();
+            }
+            args.putParcelable("intent", superIntent);
+            modIntent.putExtra(EXTRA_SHOW_FRAGMENT_ARGUMENTS, superIntent.getExtras());
+            return modIntent;
+        }
+        return superIntent;
+    }
+
+    /**
+     * Checks if the component name in the intent is different from the Settings class and
+     * returns the class name to load as a fragment.
+     */
+    private String getStartingFragmentClass(Intent intent) {
+        if (mFragmentClass != null) return mFragmentClass;
+
+        String intentClass = intent.getComponent().getClassName();
+        if (intentClass.equals(getClass().getName())) return null;
+
+        if ("com.android.settings.ManageApplications".equals(intentClass)
+                || "com.android.settings.RunningServices".equals(intentClass)
+                || "com.android.settings.applications.StorageUse".equals(intentClass)) {
+            // Old names of manage apps.
+            intentClass = com.android.settings.applications.ManageApplications.class.getName();
+        }
+
+        return intentClass;
+    }
+
+    /**
+     * Start a new fragment containing a preference panel.  If the preferences
+     * are being displayed in multi-pane mode, the given fragment class will
+     * be instantiated and placed in the appropriate pane.  If running in
+     * single-pane mode, a new activity will be launched in which to show the
+     * fragment.
+     *
+     * @param fragmentClass Full name of the class implementing the fragment.
+     * @param args Any desired arguments to supply to the fragment.
+     * @param titleRes Optional resource identifier of the title of this
+     * fragment.
+     * @param titleText Optional text of the title of this fragment.
+     * @param resultTo Optional fragment that result data should be sent to.
+     * If non-null, resultTo.onActivityResult() will be called when this
+     * preference panel is done.  The launched panel must use
+     * {@link #finishPreferencePanel(Fragment, int, Intent)} when done.
+     * @param resultRequestCode If resultTo is non-null, this is the caller's
+     * request code to be received with the resut.
+     */
+    public void startPreferencePanel(String fragmentClass, Bundle args, int titleRes,
+                                     CharSequence titleText, Fragment resultTo,
+                                     int resultRequestCode) {
+        startWithFragment(fragmentClass, args, resultTo, resultRequestCode, titleRes, 0);
+    }
+
+    /**
+     * Called by a preference panel fragment to finish itself.
+     *
+     * @param caller The fragment that is asking to be finished.
+     * @param resultCode Optional result code to send back to the original
+     * launching fragment.
+     * @param resultData Optional result data to send back to the original
+     * launching fragment.
+     */
+    public void finishPreferencePanel(Fragment caller, int resultCode, Intent resultData) {
+        setResult(resultCode, resultData);
+    }
+
+    /**
+     * Start a new fragment.
+     *
+     * @param fragment The fragment to start
+     * @param push If true, the current fragment will be pushed onto the back stack.  If false,
+     * the current fragment will be replaced.
+     */
+    public void startPreferenceFragment(Fragment fragment, boolean push) {
+        FragmentTransaction transaction = getFragmentManager().beginTransaction();
+        transaction.replace(R.id.prefs, fragment);
+        if (push) {
+            transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
+            transaction.addToBackStack(BACK_STACK_PREFS);
+        } else {
+            transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
+        }
+        transaction.commitAllowingStateLoss();
+    }
+
+    /**
+     * Start a new fragment.
+     *
+     * @param fragmentName The name of the fragment to display.
+     * @param args Optional arguments to supply to the fragment.
+     * @param resultTo Option fragment that should receive the result of
+     * the activity launch.
+     * @param resultRequestCode If resultTo is non-null, this is the request
+     * code in which to report the result.
+     * @param titleRes Resource ID of string to display for the title of
+     * this set of preferences.
+     * @param shortTitleRes Resource ID of string to display for the short title of
+     * this set of preferences.
+     */
+    private void startWithFragment(String fragmentName, Bundle args, Fragment resultTo,
+                                   int resultRequestCode, int titleRes, int shortTitleRes) {
+        Fragment f = Fragment.instantiate(this, fragmentName, args);
+        if (resultTo != null) {
+            f.setTargetFragment(resultTo, resultRequestCode);
+        }
+        FragmentTransaction transaction = getFragmentManager().beginTransaction();
+        transaction.replace(R.id.prefs, f);
+        transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
+        transaction.addToBackStack(BACK_STACK_PREFS);
+        transaction.commitAllowingStateLoss();
+
+        final CharSequence title = getText(titleRes);
+        final TitlePair pair = new TitlePair(titleRes, null);
+        mTitleStack.add(pair);
+        setTitle(title);
+    }
+
+    /**
+     * Called when the activity needs its list of headers build.  By
+     * implementing this and adding at least one item to the list, you
+     * will cause the activity to run in its modern fragment mode.  Note
+     * that this function may not always be called; for example, if the
+     * activity has been asked to display a particular fragment without
+     * the header list, there is no need to build the headers.
+     *
+     * <p>Typical implementations will use {@link #loadHeadersFromResource}
+     * to fill in the list from a resource.
+     *
+     * @param headers The list in which to place the headers.
+     */
+    private void onBuildHeaders(List<Header> headers) {
+        loadHeadersFromResource(R.xml.settings_headers, headers);
+        updateHeaderList(headers);
+    }
+
+    /**
+     * Parse the given XML file as a header description, adding each
+     * parsed Header into the target list.
+     *
+     * @param resid The XML resource to load and parse.
+     * @param target The list in which the parsed headers should be placed.
+     */
+    private void loadHeadersFromResource(int resid, List<Header> target) {
+        XmlResourceParser parser = null;
+        try {
+            parser = getResources().getXml(resid);
+            AttributeSet attrs = Xml.asAttributeSet(parser);
+
+            int type;
+            while ((type=parser.next()) != XmlPullParser.END_DOCUMENT
+                    && type != XmlPullParser.START_TAG) {
+                // Parse next until start tag is found
+            }
+
+            String nodeName = parser.getName();
+            if (!"preference-headers".equals(nodeName)) {
+                throw new RuntimeException(
+                        "XML document must start with <preference-headers> tag; found"
+                                + nodeName + " at " + parser.getPositionDescription());
+            }
+
+            Bundle curBundle = null;
+
+            final int outerDepth = parser.getDepth();
+            while ((type=parser.next()) != XmlPullParser.END_DOCUMENT
+                    && (type != XmlPullParser.END_TAG || parser.getDepth() > outerDepth)) {
+                if (type == XmlPullParser.END_TAG || type == XmlPullParser.TEXT) {
+                    continue;
+                }
+
+                nodeName = parser.getName();
+                if ("header".equals(nodeName)) {
+                    Header header = new Header();
+
+                    TypedArray sa = obtainStyledAttributes(
+                            attrs, com.android.internal.R.styleable.PreferenceHeader);
+                    header.id = sa.getResourceId(
+                            com.android.internal.R.styleable.PreferenceHeader_id,
+                            (int)HEADER_ID_UNDEFINED);
+                    TypedValue tv = sa.peekValue(
+                            com.android.internal.R.styleable.PreferenceHeader_title);
+                    if (tv != null && tv.type == TypedValue.TYPE_STRING) {
+                        if (tv.resourceId != 0) {
+                            header.titleRes = tv.resourceId;
+                        } else {
+                            header.title = tv.string;
+                        }
+                    }
+                    tv = sa.peekValue(
+                            com.android.internal.R.styleable.PreferenceHeader_summary);
+                    if (tv != null && tv.type == TypedValue.TYPE_STRING) {
+                        if (tv.resourceId != 0) {
+                            header.summaryRes = tv.resourceId;
+                        } else {
+                            header.summary = tv.string;
+                        }
+                    }
+                    header.iconRes = sa.getResourceId(
+                            com.android.internal.R.styleable.PreferenceHeader_icon, 0);
+                    header.fragment = sa.getString(
+                            com.android.internal.R.styleable.PreferenceHeader_fragment);
+                    sa.recycle();
+
+                    if (curBundle == null) {
+                        curBundle = new Bundle();
+                    }
+
+                    final int innerDepth = parser.getDepth();
+                    while ((type=parser.next()) != XmlPullParser.END_DOCUMENT
+                            && (type != XmlPullParser.END_TAG || parser.getDepth() > innerDepth)) {
+                        if (type == XmlPullParser.END_TAG || type == XmlPullParser.TEXT) {
+                            continue;
+                        }
+
+                        String innerNodeName = parser.getName();
+                        if (innerNodeName.equals("extra")) {
+                            getResources().parseBundleExtra("extra", attrs, curBundle);
+                            XmlUtils.skipCurrentTag(parser);
+
+                        } else if (innerNodeName.equals("intent")) {
+                            header.intent = Intent.parseIntent(getResources(), parser, attrs);
+
+                        } else {
+                            XmlUtils.skipCurrentTag(parser);
+                        }
+                    }
+
+                    if (curBundle.size() > 0) {
+                        header.fragmentArguments = curBundle;
+                        curBundle = null;
+                    }
+
+                    target.add(header);
+                } else {
+                    XmlUtils.skipCurrentTag(parser);
+                }
+            }
+
+        } catch (XmlPullParserException e) {
+            throw new RuntimeException("Error parsing headers", e);
+        } catch (IOException e) {
+            throw new RuntimeException("Error parsing headers", e);
+        } finally {
+            if (parser != null) parser.close();
+        }
+    }
+
+    private void updateHeaderList(List<Header> target) {
+        final boolean showDev = mDevelopmentPreferences.getBoolean(
+                DevelopmentSettings.PREF_SHOW,
+                android.os.Build.TYPE.equals("eng"));
+        int i = 0;
+
+        final UserManager um = (UserManager) getSystemService(Context.USER_SERVICE);
+        mHeaderIndexMap.clear();
+        while (i < target.size()) {
+            Header header = target.get(i);
+            // Ids are integers, so downcasting
+            int id = (int) header.id;
+            if (id == R.id.operator_settings || id == R.id.manufacturer_settings) {
+                Utils.updateHeaderToSpecificActivityFromMetaDataOrRemove(this, target, header);
+            } else if (id == R.id.wifi_settings) {
+                // Remove WiFi Settings if WiFi service is not available.
+                if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_WIFI)) {
+                    target.remove(i);
+                }
+            } else if (id == R.id.bluetooth_settings) {
+                // Remove Bluetooth Settings if Bluetooth service is not available.
+                if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH)) {
+                    target.remove(i);
+                }
+            } else if (id == R.id.data_usage_settings) {
+                // Remove data usage when kernel module not enabled
+                final INetworkManagementService netManager = INetworkManagementService.Stub
+                        .asInterface(ServiceManager.getService(Context.NETWORKMANAGEMENT_SERVICE));
+                try {
+                    if (!netManager.isBandwidthControlEnabled()) {
+                        target.remove(i);
+                    }
+                } catch (RemoteException e) {
+                    // ignored
+                }
+            } else if (id == R.id.battery_settings) {
+                // Remove battery settings when battery is not available. (e.g. TV)
+
+                if (!mBatteryPresent) {
+                    target.remove(i);
+                }
+            } else if (id == R.id.account_settings) {
+                int headerIndex = i + 1;
+                i = insertAccountsHeaders(target, headerIndex);
+            } else if (id == R.id.home_settings) {
+                if (!updateHomeSettingHeaders(header)) {
+                    target.remove(i);
+                }
+            } else if (id == R.id.user_settings) {
+                if (!UserHandle.MU_ENABLED
+                        || !UserManager.supportsMultipleUsers()
+                        || Utils.isMonkeyRunning()) {
+                    target.remove(i);
+                }
+            } else if (id == R.id.nfc_payment_settings) {
+                if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_NFC)) {
+                    target.remove(i);
+                } else {
+                    // Only show if NFC is on and we have the HCE feature
+                    NfcAdapter adapter = NfcAdapter.getDefaultAdapter(this);
+                    if (!adapter.isEnabled() || !getPackageManager().hasSystemFeature(
+                            PackageManager.FEATURE_NFC_HOST_CARD_EMULATION)) {
+                        target.remove(i);
+                    }
+                }
+            } else if (id == R.id.development_settings) {
+                if (!showDev) {
+                    target.remove(i);
+                }
+            } else if (id == R.id.account_add) {
+                if (um.hasUserRestriction(UserManager.DISALLOW_MODIFY_ACCOUNTS)) {
+                    target.remove(i);
+                }
+            }
+
+            if (i < target.size() && target.get(i) == header
+                    && UserHandle.MU_ENABLED && UserHandle.myUserId() != 0
+                    && !ArrayUtils.contains(SETTINGS_FOR_RESTRICTED, id)) {
+                target.remove(i);
+            }
+
+            // Increment if the current one wasn't removed by the Utils code.
+            if (i < target.size() && target.get(i) == header) {
+                // Hold on to the first header, when we need to reset to the top-level
+                if (mFirstHeader == null &&
+                        HeaderAdapter.getHeaderType(header) != HeaderAdapter.HEADER_TYPE_CATEGORY) {
+                    mFirstHeader = header;
+                }
+                mHeaderIndexMap.put(id, i);
+                i++;
+            }
+        }
+    }
+
+    private int insertAccountsHeaders(List<Header> target, int headerIndex) {
+        String[] accountTypes = mAuthenticatorHelper.getEnabledAccountTypes();
+        List<Header> accountHeaders = new ArrayList<Header>(accountTypes.length);
+        for (String accountType : accountTypes) {
+            CharSequence label = mAuthenticatorHelper.getLabelForType(this, accountType);
+            if (label == null) {
+                continue;
+            }
+
+            Account[] accounts = AccountManager.get(this).getAccountsByType(accountType);
+            boolean skipToAccount = accounts.length == 1
+                    && !mAuthenticatorHelper.hasAccountPreferences(accountType);
+            Header accHeader = new Header();
+            accHeader.title = label;
+            if (accHeader.extras == null) {
+                accHeader.extras = new Bundle();
+            }
+            if (skipToAccount) {
+                accHeader.fragment = AccountSyncSettings.class.getName();
+                accHeader.fragmentArguments = new Bundle();
+                // Need this for the icon
+                accHeader.extras.putString(ManageAccountsSettings.KEY_ACCOUNT_TYPE, accountType);
+                accHeader.extras.putParcelable(AccountSyncSettings.ACCOUNT_KEY, accounts[0]);
+                accHeader.fragmentArguments.putParcelable(AccountSyncSettings.ACCOUNT_KEY,
+                        accounts[0]);
+            } else {
+                accHeader.fragment = ManageAccountsSettings.class.getName();
+                accHeader.fragmentArguments = new Bundle();
+                accHeader.extras.putString(ManageAccountsSettings.KEY_ACCOUNT_TYPE, accountType);
+                accHeader.fragmentArguments.putString(ManageAccountsSettings.KEY_ACCOUNT_TYPE,
+                        accountType);
+                    accHeader.fragmentArguments.putString(ManageAccountsSettings.KEY_ACCOUNT_LABEL,
+                            label.toString());
+            }
+            accountHeaders.add(accHeader);
+            mAuthenticatorHelper.preloadDrawableForType(this, accountType);
+        }
+
+        // Sort by label
+        Collections.sort(accountHeaders, new Comparator<Header>() {
+            @Override
+            public int compare(Header h1, Header h2) {
+                return h1.title.toString().compareTo(h2.title.toString());
+            }
+        });
+
+        for (Header header : accountHeaders) {
+            target.add(headerIndex++, header);
+        }
+        if (!mListeningToAccountUpdates) {
+            AccountManager.get(this).addOnAccountsUpdatedListener(this, null, true);
+            mListeningToAccountUpdates = true;
+        }
+        return headerIndex;
+    }
+
+    private boolean updateHomeSettingHeaders(Header header) {
+        // Once we decide to show Home settings, keep showing it forever
+        SharedPreferences sp = getSharedPreferences(HomeSettings.HOME_PREFS, Context.MODE_PRIVATE);
+        if (sp.getBoolean(HomeSettings.HOME_PREFS_DO_SHOW, false)) {
+            return true;
+        }
+
+        try {
+            final ArrayList<ResolveInfo> homeApps = new ArrayList<ResolveInfo>();
+            getPackageManager().getHomeActivities(homeApps);
+            if (homeApps.size() < 2) {
+                // When there's only one available home app, omit this settings
+                // category entirely at the top level UI.  If the user just
+                // uninstalled the penultimate home app candidiate, we also
+                // now tell them about why they aren't seeing 'Home' in the list.
+                if (sShowNoHomeNotice) {
+                    sShowNoHomeNotice = false;
+                    NoHomeDialogFragment.show(this);
+                }
+                return false;
+            } else {
+                // Okay, we're allowing the Home settings category.  Tell it, when
+                // invoked via this front door, that we'll need to be told about the
+                // case when the user uninstalls all but one home app.
+                if (header.fragmentArguments == null) {
+                    header.fragmentArguments = new Bundle();
+                }
+                header.fragmentArguments.putBoolean(HomeSettings.HOME_SHOW_NOTICE, true);
+            }
+        } catch (Exception e) {
+            // Can't look up the home activity; bail on configuring the icon
+            Log.w(LOG_TAG, "Problem looking up home activity!", e);
+        }
+
+        sp.edit().putBoolean(HomeSettings.HOME_PREFS_DO_SHOW, true).apply();
+        return true;
+    }
+
+    private void getMetaData() {
+        try {
+            ActivityInfo ai = getPackageManager().getActivityInfo(getComponentName(),
+                    PackageManager.GET_META_DATA);
+            if (ai == null || ai.metaData == null) return;
+            mTopLevelHeaderId = ai.metaData.getInt(META_DATA_KEY_HEADER_ID);
+            mFragmentClass = ai.metaData.getString(META_DATA_KEY_FRAGMENT_CLASS);
+        } catch (NameNotFoundException nnfe) {
+            // No recovery
+            Log.d(LOG_TAG, "Cannot get Metadata for: " + getComponentName().toString());
+        }
+    }
+
+    // give subclasses access to the Next button
+    public boolean hasNextButton() {
+        return mNextButton != null;
+    }
+
+    public Button getNextButton() {
+        return mNextButton;
+    }
+
+    public static class NoHomeDialogFragment extends DialogFragment {
+        public static void show(Activity parent) {
+            final NoHomeDialogFragment dialog = new NoHomeDialogFragment();
+            dialog.show(parent.getFragmentManager(), null);
+        }
+
+        @Override
+        public Dialog onCreateDialog(Bundle savedInstanceState) {
+            return new AlertDialog.Builder(getActivity())
+                    .setMessage(R.string.only_one_home_message)
+                    .setPositiveButton(android.R.string.ok, null)
+                    .create();
+        }
+    }
+
+    private static class HeaderAdapter extends ArrayAdapter<Header> {
+        static final int HEADER_TYPE_CATEGORY = 0;
+        static final int HEADER_TYPE_NORMAL = 1;
+        static final int HEADER_TYPE_SWITCH = 2;
+        static final int HEADER_TYPE_BUTTON = 3;
+        private static final int HEADER_TYPE_COUNT = HEADER_TYPE_BUTTON + 1;
+
+        private final WifiEnabler mWifiEnabler;
+        private final BluetoothEnabler mBluetoothEnabler;
+        private AuthenticatorHelper mAuthHelper;
+        private DevicePolicyManager mDevicePolicyManager;
+
+        private static class HeaderViewHolder {
+            ImageView mIcon;
+            TextView mTitle;
+            TextView mSummary;
+            Switch mSwitch;
+            ImageButton mButton;
+            View mDivider;
+        }
+
+        private LayoutInflater mInflater;
+
+        static int getHeaderType(Header header) {
+            if (header.fragment == null && header.intent == null) {
+                return HEADER_TYPE_CATEGORY;
+            } else if (header.id == R.id.wifi_settings || header.id == R.id.bluetooth_settings) {
+                return HEADER_TYPE_SWITCH;
+            } else if (header.id == R.id.security_settings) {
+                return HEADER_TYPE_BUTTON;
+            } else {
+                return HEADER_TYPE_NORMAL;
+            }
+        }
+
+        @Override
+        public int getItemViewType(int position) {
+            Header header = getItem(position);
+            return getHeaderType(header);
+        }
+
+        @Override
+        public boolean areAllItemsEnabled() {
+            return false; // because of categories
+        }
+
+        @Override
+        public boolean isEnabled(int position) {
+            return getItemViewType(position) != HEADER_TYPE_CATEGORY;
+        }
+
+        @Override
+        public int getViewTypeCount() {
+            return HEADER_TYPE_COUNT;
+        }
+
+        @Override
+        public boolean hasStableIds() {
+            return true;
+        }
+
+        public HeaderAdapter(Context context, List<Header> objects,
+                AuthenticatorHelper authenticatorHelper, DevicePolicyManager dpm) {
+            super(context, 0, objects);
+
+            mAuthHelper = authenticatorHelper;
+            mInflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
+
+            // Temp Switches provided as placeholder until the adapter replaces these with actual
+            // Switches inflated from their layouts. Must be done before adapter is set in super
+            mWifiEnabler = new WifiEnabler(context, new Switch(context));
+            mBluetoothEnabler = new BluetoothEnabler(context, new Switch(context));
+            mDevicePolicyManager = dpm;
+        }
+
+        @Override
+        public View getView(int position, View convertView, ViewGroup parent) {
+            HeaderViewHolder holder;
+            Header header = getItem(position);
+            int headerType = getHeaderType(header);
+            View view = null;
+
+            if (convertView == null) {
+                holder = new HeaderViewHolder();
+                switch (headerType) {
+                    case HEADER_TYPE_CATEGORY:
+                        view = new TextView(getContext(), null,
+                                android.R.attr.listSeparatorTextViewStyle);
+                        holder.mTitle = (TextView) view;
+                        break;
+
+                    case HEADER_TYPE_SWITCH:
+                        view = mInflater.inflate(R.layout.preference_header_switch_item, parent,
+                                false);
+                        holder.mIcon = (ImageView) view.findViewById(R.id.icon);
+                        holder.mTitle = (TextView)
+                                view.findViewById(com.android.internal.R.id.title);
+                        holder.mSummary = (TextView)
+                                view.findViewById(com.android.internal.R.id.summary);
+                        holder.mSwitch = (Switch) view.findViewById(R.id.switchWidget);
+                        break;
+
+                    case HEADER_TYPE_BUTTON:
+                        view = mInflater.inflate(R.layout.preference_header_button_item, parent,
+                                false);
+                        holder.mIcon = (ImageView) view.findViewById(R.id.icon);
+                        holder.mTitle = (TextView)
+                                view.findViewById(com.android.internal.R.id.title);
+                        holder.mSummary = (TextView)
+                                view.findViewById(com.android.internal.R.id.summary);
+                        holder.mButton = (ImageButton) view.findViewById(R.id.buttonWidget);
+                        holder.mDivider = view.findViewById(R.id.divider);
+                        break;
+
+                    case HEADER_TYPE_NORMAL:
+                        view = mInflater.inflate(
+                                R.layout.preference_header_item, parent,
+                                false);
+                        holder.mIcon = (ImageView) view.findViewById(R.id.icon);
+                        holder.mTitle = (TextView)
+                                view.findViewById(com.android.internal.R.id.title);
+                        holder.mSummary = (TextView)
+                                view.findViewById(com.android.internal.R.id.summary);
+                        break;
+                }
+                view.setTag(holder);
+            } else {
+                view = convertView;
+                holder = (HeaderViewHolder) view.getTag();
+            }
+
+            // All view fields must be updated every time, because the view may be recycled
+            switch (headerType) {
+                case HEADER_TYPE_CATEGORY:
+                    holder.mTitle.setText(header.getTitle(getContext().getResources()));
+                    break;
+
+                case HEADER_TYPE_SWITCH:
+                    // Would need a different treatment if the main menu had more switches
+                    if (header.id == R.id.wifi_settings) {
+                        mWifiEnabler.setSwitch(holder.mSwitch);
+                    } else {
+                        mBluetoothEnabler.setSwitch(holder.mSwitch);
+                    }
+                    updateCommonHeaderView(header, holder);
+                    break;
+
+                case HEADER_TYPE_BUTTON:
+                    if (header.id == R.id.security_settings) {
+                        boolean hasCert = DevicePolicyManager.hasAnyCaCertsInstalled();
+                        if (hasCert) {
+                            holder.mButton.setVisibility(View.VISIBLE);
+                            holder.mDivider.setVisibility(View.VISIBLE);
+                            boolean isManaged = mDevicePolicyManager.getDeviceOwner() != null;
+                            if (isManaged) {
+                                holder.mButton.setImageResource(R.drawable.ic_settings_about);
+                            } else {
+                                holder.mButton.setImageResource(
+                                        android.R.drawable.stat_notify_error);
+                            }
+                            holder.mButton.setOnClickListener(new OnClickListener() {
+                                @Override
+                                public void onClick(View v) {
+                                    Intent intent = new Intent(
+                                            android.provider.Settings.ACTION_MONITORING_CERT_INFO);
+                                    getContext().startActivity(intent);
+                                }
+                            });
+                        } else {
+                            holder.mButton.setVisibility(View.GONE);
+                            holder.mDivider.setVisibility(View.GONE);
+                        }
+                    }
+                    updateCommonHeaderView(header, holder);
+                    break;
+
+                case HEADER_TYPE_NORMAL:
+                    updateCommonHeaderView(header, holder);
+                    break;
+            }
+
+            return view;
+        }
+
+        private void updateCommonHeaderView(Header header, HeaderViewHolder holder) {
+                if (header.extras != null
+                        && header.extras.containsKey(ManageAccountsSettings.KEY_ACCOUNT_TYPE)) {
+                    String accType = header.extras.getString(
+                            ManageAccountsSettings.KEY_ACCOUNT_TYPE);
+                    Drawable icon = mAuthHelper.getDrawableForType(getContext(), accType);
+                    setHeaderIcon(holder, icon);
+                } else {
+                    holder.mIcon.setImageResource(header.iconRes);
+                }
+                holder.mTitle.setText(header.getTitle(getContext().getResources()));
+                CharSequence summary = header.getSummary(getContext().getResources());
+                if (!TextUtils.isEmpty(summary)) {
+                    holder.mSummary.setVisibility(View.VISIBLE);
+                    holder.mSummary.setText(summary);
+                } else {
+                    holder.mSummary.setVisibility(View.GONE);
+                }
+            }
+
+        private void setHeaderIcon(HeaderViewHolder holder, Drawable icon) {
+            ViewGroup.LayoutParams lp = holder.mIcon.getLayoutParams();
+            lp.width = getContext().getResources().getDimensionPixelSize(
+                    R.dimen.header_icon_width);
+            lp.height = lp.width;
+            holder.mIcon.setLayoutParams(lp);
+            holder.mIcon.setImageDrawable(icon);
+        }
+
+        public void resume() {
+            mWifiEnabler.resume();
+            mBluetoothEnabler.resume();
+        }
+
+        public void pause() {
+            mWifiEnabler.pause();
+            mBluetoothEnabler.pause();
+        }
+    }
+
+    private void onListItemClick(ListView l, View v, int position, long id) {
+        if (!isResumed()) {
+            return;
+        }
+        Object item = mHeaderAdapter.getItem(position);
+        if (item instanceof Header) {
+            mCurrentHeader = (Header) item;
+        }
+    }
+
+    /**
+     * Called when the user selects an item in the header list.  The default
+     * implementation will call either
+     * {@link #startWithFragment(String, Bundle, Fragment, int, int, int)}
+     * or {@link #switchToHeader(com.android.settings.SettingsActivity.Header, boolean)}
+     * as appropriate.
+     *
+     * @param header The header that was selected.
+     */
+    private void onHeaderClick(Header header) {
+        if (header == null) return;
+        if (header.fragment != null) {
+            switchToHeader(header, false);
+        } else if (header.intent != null) {
+            startActivity(header.intent);
+        }
+    }
+
+    @Override
+    public boolean shouldUpRecreateTask(Intent targetIntent) {
+        return super.shouldUpRecreateTask(new Intent(this, SettingsActivity.class));
+    }
+
+    @Override
+    public void onAccountsUpdated(Account[] accounts) {
+        // TODO: watch for package upgrades to invalidate cache; see 7206643
+        mAuthenticatorHelper.updateAuthDescriptions(this);
+        mAuthenticatorHelper.onAccountsUpdated(this, accounts);
+        invalidateHeaders();
+    }
+
+    public static void requestHomeNotice() {
+        sShowNoHomeNotice = true;
+    }
+
+    /**
+     * Default value for {@link Header#id Header.id} indicating that no
+     * identifier value is set.  All other values (including those below -1)
+     * are valid.
+     */
+    private static final long HEADER_ID_UNDEFINED = -1;
+
+    /**
+     * Description of a single Header item that the user can select.
+     */
+    static final class Header implements Parcelable {
+        /**
+         * Identifier for this header, to correlate with a new list when
+         * it is updated.  The default value is
+         * {@link SettingsActivity#HEADER_ID_UNDEFINED}, meaning no id.
+         * @attr ref android.R.styleable#PreferenceHeader_id
+         */
+        public long id = HEADER_ID_UNDEFINED;
+
+        /**
+         * Resource ID of title of the header that is shown to the user.
+         * @attr ref android.R.styleable#PreferenceHeader_title
+         */
+        public int titleRes;
+
+        /**
+         * Title of the header that is shown to the user.
+         * @attr ref android.R.styleable#PreferenceHeader_title
+         */
+        public CharSequence title;
+
+        /**
+         * Resource ID of optional summary describing what this header controls.
+         * @attr ref android.R.styleable#PreferenceHeader_summary
+         */
+        public int summaryRes;
+
+        /**
+         * Optional summary describing what this header controls.
+         * @attr ref android.R.styleable#PreferenceHeader_summary
+         */
+        public CharSequence summary;
+
+        /**
+         * Optional icon resource to show for this header.
+         * @attr ref android.R.styleable#PreferenceHeader_icon
+         */
+        public int iconRes;
+
+        /**
+         * Full class name of the fragment to display when this header is
+         * selected.
+         * @attr ref android.R.styleable#PreferenceHeader_fragment
+         */
+        public String fragment;
+
+        /**
+         * Optional arguments to supply to the fragment when it is
+         * instantiated.
+         */
+        public Bundle fragmentArguments;
+
+        /**
+         * Intent to launch when the preference is selected.
+         */
+        public Intent intent;
+
+        /**
+         * Optional additional data for use by subclasses of the activity
+         */
+        public Bundle extras;
+
+        public Header() {
+            // Empty
+        }
+
+        /**
+         * Return the currently set title.  If {@link #titleRes} is set,
+         * this resource is loaded from <var>res</var> and returned.  Otherwise
+         * {@link #title} is returned.
+         */
+        public CharSequence getTitle(Resources res) {
+            if (titleRes != 0) {
+                return res.getText(titleRes);
+            }
+            return title;
+        }
+
+        /**
+         * Return the currently set summary.  If {@link #summaryRes} is set,
+         * this resource is loaded from <var>res</var> and returned.  Otherwise
+         * {@link #summary} is returned.
+         */
+        public CharSequence getSummary(Resources res) {
+            if (summaryRes != 0) {
+                return res.getText(summaryRes);
+            }
+            return summary;
+        }
+
+        @Override
+        public int describeContents() {
+            return 0;
+        }
+
+        @Override
+        public void writeToParcel(Parcel dest, int flags) {
+            dest.writeLong(id);
+            dest.writeInt(titleRes);
+            TextUtils.writeToParcel(title, dest, flags);
+            dest.writeInt(summaryRes);
+            TextUtils.writeToParcel(summary, dest, flags);
+            dest.writeInt(iconRes);
+            dest.writeString(fragment);
+            dest.writeBundle(fragmentArguments);
+            if (intent != null) {
+                dest.writeInt(1);
+                intent.writeToParcel(dest, flags);
+            } else {
+                dest.writeInt(0);
+            }
+            dest.writeBundle(extras);
+        }
+
+        public void readFromParcel(Parcel in) {
+            id = in.readLong();
+            titleRes = in.readInt();
+            title = TextUtils.CHAR_SEQUENCE_CREATOR.createFromParcel(in);
+            summaryRes = in.readInt();
+            summary = TextUtils.CHAR_SEQUENCE_CREATOR.createFromParcel(in);
+            iconRes = in.readInt();
+            fragment = in.readString();
+            fragmentArguments = in.readBundle();
+            if (in.readInt() != 0) {
+                intent = Intent.CREATOR.createFromParcel(in);
+            }
+            extras = in.readBundle();
+        }
+
+        Header(Parcel in) {
+            readFromParcel(in);
+        }
+
+        public static final Creator<Header> CREATOR = new Creator<Header>() {
+            public Header createFromParcel(Parcel source) {
+                return new Header(source);
+            }
+            public Header[] newArray(int size) {
+                return new Header[size];
+            }
+        };
+    }
+}