src/com/android/settings/inputmethod/PhysicalKeyboardFragment.java - LeafOS-Project/android_packages_apps_Settings - Gitiles

 /*
  * Copyright (C) 2016 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.inputmethod;

 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.app.Activity;
 import android.app.settings.SettingsEnums;
 import android.content.Context;
 import android.content.Intent;
 import android.database.ContentObserver;
 import android.hardware.input.InputDeviceIdentifier;
 import android.hardware.input.InputManager;
 import android.hardware.input.KeyboardLayout;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.UserHandle;
 import android.provider.SearchIndexableResource;
 import android.provider.Settings.Secure;
 import android.text.TextUtils;
 import android.view.InputDevice;

 import androidx.preference.Preference;
 import androidx.preference.Preference.OnPreferenceChangeListener;
 import androidx.preference.PreferenceCategory;
 import androidx.preference.PreferenceScreen;
 import androidx.preference.SwitchPreference;

 import com.android.internal.util.Preconditions;
 import com.android.settings.R;
 import com.android.settings.Settings;
 import com.android.settings.SettingsPreferenceFragment;
 import com.android.settings.search.BaseSearchIndexProvider;
 import com.android.settings.search.Indexable;
 import com.android.settingslib.search.SearchIndexable;
 import com.android.settingslib.utils.ThreadUtils;

 import java.text.Collator;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Objects;

 @SearchIndexable
 public final class PhysicalKeyboardFragment extends SettingsPreferenceFragment
         implements InputManager.InputDeviceListener,
         KeyboardLayoutDialogFragment.OnSetupKeyboardLayoutsListener {

     private static final String KEYBOARD_ASSISTANCE_CATEGORY = "keyboard_assistance_category";
     private static final String SHOW_VIRTUAL_KEYBOARD_SWITCH = "show_virtual_keyboard_switch";
     private static final String KEYBOARD_SHORTCUTS_HELPER = "keyboard_shortcuts_helper";

     @NonNull
     private final ArrayList<HardKeyboardDeviceInfo> mLastHardKeyboards = new ArrayList<>();

     private InputManager mIm;
     @NonNull
     private PreferenceCategory mKeyboardAssistanceCategory;
     @NonNull
     private SwitchPreference mShowVirtualKeyboardSwitch;

     private Intent mIntentWaitingForResult;

     @Override
     public void onCreatePreferences(Bundle bundle, String s) {
         Activity activity = Preconditions.checkNotNull(getActivity());
         addPreferencesFromResource(R.xml.physical_keyboard_settings);
         mIm = Preconditions.checkNotNull(activity.getSystemService(InputManager.class));
         mKeyboardAssistanceCategory = Preconditions.checkNotNull(
                 (PreferenceCategory) findPreference(KEYBOARD_ASSISTANCE_CATEGORY));
         mShowVirtualKeyboardSwitch = Preconditions.checkNotNull(
                 (SwitchPreference) mKeyboardAssistanceCategory.findPreference(
                         SHOW_VIRTUAL_KEYBOARD_SWITCH));
         findPreference(KEYBOARD_SHORTCUTS_HELPER).setOnPreferenceClickListener(
                 new Preference.OnPreferenceClickListener() {
                     @Override
                     public boolean onPreferenceClick(Preference preference) {
                         toggleKeyboardShortcutsMenu();
                         return true;
                     }
                 });
     }

     @Override
     public void onResume() {
         super.onResume();
         mLastHardKeyboards.clear();
         scheduleUpdateHardKeyboards();
         mIm.registerInputDeviceListener(this, null);
         mShowVirtualKeyboardSwitch.setOnPreferenceChangeListener(
                 mShowVirtualKeyboardSwitchPreferenceChangeListener);
         registerShowVirtualKeyboardSettingsObserver();
     }

     @Override
     public void onPause() {
         super.onPause();
         mLastHardKeyboards.clear();
         mIm.unregisterInputDeviceListener(this);
         mShowVirtualKeyboardSwitch.setOnPreferenceChangeListener(null);
         unregisterShowVirtualKeyboardSettingsObserver();
     }

     @Override
     public void onInputDeviceAdded(int deviceId) {
         scheduleUpdateHardKeyboards();
     }

     @Override
     public void onInputDeviceRemoved(int deviceId) {
         scheduleUpdateHardKeyboards();
     }

     @Override
     public void onInputDeviceChanged(int deviceId) {
         scheduleUpdateHardKeyboards();
     }

     @Override
     public int getMetricsCategory() {
         return SettingsEnums.PHYSICAL_KEYBOARDS;
     }

     private void scheduleUpdateHardKeyboards() {
         final Context context = getContext();
         ThreadUtils.postOnBackgroundThread(() -> {
             final List<HardKeyboardDeviceInfo> newHardKeyboards = getHardKeyboards(context);
             ThreadUtils.postOnMainThread(() -> updateHardKeyboards(newHardKeyboards));
         });
     }

     private void updateHardKeyboards(@NonNull List<HardKeyboardDeviceInfo> newHardKeyboards) {
         if (Objects.equals(mLastHardKeyboards, newHardKeyboards)) {
             // Nothing has changed.  Ignore.
             return;
         }

         // TODO(yukawa): Maybe we should follow the style used in ConnectedDeviceDashboardFragment.

         mLastHardKeyboards.clear();
         mLastHardKeyboards.addAll(newHardKeyboards);

         final PreferenceScreen preferenceScreen = getPreferenceScreen();
         preferenceScreen.removeAll();
         final PreferenceCategory category = new PreferenceCategory(getPrefContext());
         category.setTitle(R.string.builtin_keyboard_settings_title);
         category.setOrder(0);
         preferenceScreen.addPreference(category);

         for (HardKeyboardDeviceInfo hardKeyboardDeviceInfo : newHardKeyboards) {
             // TODO(yukawa): Consider using com.android.settings.widget.GearPreference
             final Preference pref = new Preference(getPrefContext());
             pref.setTitle(hardKeyboardDeviceInfo.mDeviceName);
             pref.setSummary(hardKeyboardDeviceInfo.mLayoutLabel);
             pref.setOnPreferenceClickListener(preference -> {
                 showKeyboardLayoutDialog(hardKeyboardDeviceInfo.mDeviceIdentifier);
                 return true;
             });
             category.addPreference(pref);
         }

         mKeyboardAssistanceCategory.setOrder(1);
         preferenceScreen.addPreference(mKeyboardAssistanceCategory);
         updateShowVirtualKeyboardSwitch();
     }

     private void showKeyboardLayoutDialog(InputDeviceIdentifier inputDeviceIdentifier) {
         KeyboardLayoutDialogFragment fragment = new KeyboardLayoutDialogFragment(
                 inputDeviceIdentifier);
         fragment.setTargetFragment(this, 0);
         fragment.show(getActivity().getSupportFragmentManager(), "keyboardLayout");
     }

     private void registerShowVirtualKeyboardSettingsObserver() {
         unregisterShowVirtualKeyboardSettingsObserver();
         getActivity().getContentResolver().registerContentObserver(
                 Secure.getUriFor(Secure.SHOW_IME_WITH_HARD_KEYBOARD),
                 false,
                 mContentObserver,
                 UserHandle.myUserId());
         updateShowVirtualKeyboardSwitch();
     }

     private void unregisterShowVirtualKeyboardSettingsObserver() {
         getActivity().getContentResolver().unregisterContentObserver(mContentObserver);
     }

     private void updateShowVirtualKeyboardSwitch() {
         mShowVirtualKeyboardSwitch.setChecked(
                 Secure.getInt(getContentResolver(), Secure.SHOW_IME_WITH_HARD_KEYBOARD, 0) != 0);
     }

     private void toggleKeyboardShortcutsMenu() {
         getActivity().requestShowKeyboardShortcuts();
     }

     private final OnPreferenceChangeListener mShowVirtualKeyboardSwitchPreferenceChangeListener =
             (preference, newValue) -> {
                 Secure.putInt(getContentResolver(), Secure.SHOW_IME_WITH_HARD_KEYBOARD,
                         ((Boolean) newValue) ? 1 : 0);
                 return true;
             };

     private final ContentObserver mContentObserver = new ContentObserver(new Handler(true)) {
         @Override
         public void onChange(boolean selfChange) {
             updateShowVirtualKeyboardSwitch();
         }
     };

     @Override
     public void onSetupKeyboardLayouts(InputDeviceIdentifier inputDeviceIdentifier) {
         final Intent intent = new Intent(Intent.ACTION_MAIN);
         intent.setClass(getActivity(), Settings.KeyboardLayoutPickerActivity.class);
         intent.putExtra(KeyboardLayoutPickerFragment.EXTRA_INPUT_DEVICE_IDENTIFIER,
                 inputDeviceIdentifier);
         mIntentWaitingForResult = intent;
         startActivityForResult(intent, 0);
     }

     @Override
     public void onActivityResult(int requestCode, int resultCode, Intent data) {
         super.onActivityResult(requestCode, resultCode, data);

         if (mIntentWaitingForResult != null) {
             InputDeviceIdentifier inputDeviceIdentifier = mIntentWaitingForResult
                     .getParcelableExtra(KeyboardLayoutPickerFragment.EXTRA_INPUT_DEVICE_IDENTIFIER);
             mIntentWaitingForResult = null;
             showKeyboardLayoutDialog(inputDeviceIdentifier);
         }
     }

     private static String getLayoutLabel(@NonNull InputDevice device,
             @NonNull Context context, @NonNull InputManager im) {
         final String currentLayoutDesc =
                 im.getCurrentKeyboardLayoutForInputDevice(device.getIdentifier());
         if (currentLayoutDesc == null) {
             return context.getString(R.string.keyboard_layout_default_label);
         }
         final KeyboardLayout currentLayout = im.getKeyboardLayout(currentLayoutDesc);
         if (currentLayout == null) {
             return context.getString(R.string.keyboard_layout_default_label);
         }
         // If current layout is specified but the layout is null, just return an empty string
         // instead of falling back to R.string.keyboard_layout_default_label.
         return TextUtils.emptyIfNull(currentLayout.getLabel());
     }

     @NonNull
     static List<HardKeyboardDeviceInfo> getHardKeyboards(@NonNull Context context) {
         final List<HardKeyboardDeviceInfo> keyboards = new ArrayList<>();
         final InputManager im = context.getSystemService(InputManager.class);
         if (im == null) {
             return new ArrayList<>();
         }
         for (int deviceId : InputDevice.getDeviceIds()) {
             final InputDevice device = InputDevice.getDevice(deviceId);
             if (device == null || device.isVirtual() || !device.isFullKeyboard()) {
                 continue;
             }
             keyboards.add(new HardKeyboardDeviceInfo(
                     device.getName(), device.getIdentifier(), getLayoutLabel(device, context, im)));
         }

         // We intentionally don't reuse Comparator because Collator may not be thread-safe.
         final Collator collator = Collator.getInstance();
         keyboards.sort((a, b) -> {
             int result = collator.compare(a.mDeviceName, b.mDeviceName);
             if (result != 0) {
                 return result;
             }
             result = a.mDeviceIdentifier.getDescriptor().compareTo(
                     b.mDeviceIdentifier.getDescriptor());
             if (result != 0) {
                 return result;
             }
             return collator.compare(a.mLayoutLabel, b.mLayoutLabel);
         });
         return keyboards;
     }

     public static final class HardKeyboardDeviceInfo {
         @NonNull
         public final String mDeviceName;
         @NonNull
         public final InputDeviceIdentifier mDeviceIdentifier;
         @NonNull
         public final String mLayoutLabel;

         public HardKeyboardDeviceInfo(
                 @Nullable String deviceName,
                 @NonNull InputDeviceIdentifier deviceIdentifier,
                 @NonNull String layoutLabel) {
             mDeviceName = TextUtils.emptyIfNull(deviceName);
             mDeviceIdentifier = deviceIdentifier;
             mLayoutLabel = layoutLabel;
         }

         @Override
         public boolean equals(Object o) {
             if (o == this) return true;
             if (o == null) return false;

             if (!(o instanceof HardKeyboardDeviceInfo)) return false;

             final HardKeyboardDeviceInfo that = (HardKeyboardDeviceInfo) o;
             if (!TextUtils.equals(mDeviceName, that.mDeviceName)) {
                 return false;
             }
             if (!Objects.equals(mDeviceIdentifier, that.mDeviceIdentifier)) {
                 return false;
             }
             if (!TextUtils.equals(mLayoutLabel, that.mLayoutLabel)) {
                 return false;
             }

             return true;
         }
     }

     public static final Indexable.SearchIndexProvider SEARCH_INDEX_DATA_PROVIDER =
             new BaseSearchIndexProvider() {
                 @Override
                 public List<SearchIndexableResource> getXmlResourcesToIndex(
                         Context context, boolean enabled) {
                     final SearchIndexableResource sir = new SearchIndexableResource(context);
                     sir.xmlResId = R.xml.physical_keyboard_settings;
                     return Arrays.asList(sir);
                 }
             };
 }
	/*
	* Copyright (C) 2016 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.inputmethod;

	import android.annotation.NonNull;
	import android.annotation.Nullable;
	import android.app.Activity;
	import android.app.settings.SettingsEnums;
	import android.content.Context;
	import android.content.Intent;
	import android.database.ContentObserver;
	import android.hardware.input.InputDeviceIdentifier;
	import android.hardware.input.InputManager;
	import android.hardware.input.KeyboardLayout;
	import android.os.Bundle;
	import android.os.Handler;
	import android.os.UserHandle;
	import android.provider.SearchIndexableResource;
	import android.provider.Settings.Secure;
	import android.text.TextUtils;
	import android.view.InputDevice;

	import androidx.preference.Preference;
	import androidx.preference.Preference.OnPreferenceChangeListener;
	import androidx.preference.PreferenceCategory;
	import androidx.preference.PreferenceScreen;
	import androidx.preference.SwitchPreference;

	import com.android.internal.util.Preconditions;
	import com.android.settings.R;
	import com.android.settings.Settings;
	import com.android.settings.SettingsPreferenceFragment;
	import com.android.settings.search.BaseSearchIndexProvider;
	import com.android.settings.search.Indexable;
	import com.android.settingslib.search.SearchIndexable;
	import com.android.settingslib.utils.ThreadUtils;

	import java.text.Collator;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.List;
	import java.util.Objects;

	@SearchIndexable
	public final class PhysicalKeyboardFragment extends SettingsPreferenceFragment
	implements InputManager.InputDeviceListener,
	KeyboardLayoutDialogFragment.OnSetupKeyboardLayoutsListener {

	private static final String KEYBOARD_ASSISTANCE_CATEGORY = "keyboard_assistance_category";
	private static final String SHOW_VIRTUAL_KEYBOARD_SWITCH = "show_virtual_keyboard_switch";
	private static final String KEYBOARD_SHORTCUTS_HELPER = "keyboard_shortcuts_helper";

	@NonNull
	private final ArrayList<HardKeyboardDeviceInfo> mLastHardKeyboards = new ArrayList<>();

	private InputManager mIm;
	@NonNull
	private PreferenceCategory mKeyboardAssistanceCategory;
	@NonNull
	private SwitchPreference mShowVirtualKeyboardSwitch;

	private Intent mIntentWaitingForResult;

	@Override
	public void onCreatePreferences(Bundle bundle, String s) {
	Activity activity = Preconditions.checkNotNull(getActivity());
	addPreferencesFromResource(R.xml.physical_keyboard_settings);
	mIm = Preconditions.checkNotNull(activity.getSystemService(InputManager.class));
	mKeyboardAssistanceCategory = Preconditions.checkNotNull(
	(PreferenceCategory) findPreference(KEYBOARD_ASSISTANCE_CATEGORY));
	mShowVirtualKeyboardSwitch = Preconditions.checkNotNull(
	(SwitchPreference) mKeyboardAssistanceCategory.findPreference(
	SHOW_VIRTUAL_KEYBOARD_SWITCH));
	findPreference(KEYBOARD_SHORTCUTS_HELPER).setOnPreferenceClickListener(
	new Preference.OnPreferenceClickListener() {
	@Override
	public boolean onPreferenceClick(Preference preference) {
	toggleKeyboardShortcutsMenu();
	return true;
	}
	});
	}

	@Override
	public void onResume() {
	super.onResume();
	mLastHardKeyboards.clear();
	scheduleUpdateHardKeyboards();
	mIm.registerInputDeviceListener(this, null);
	mShowVirtualKeyboardSwitch.setOnPreferenceChangeListener(
	mShowVirtualKeyboardSwitchPreferenceChangeListener);
	registerShowVirtualKeyboardSettingsObserver();
	}

	@Override
	public void onPause() {
	super.onPause();
	mLastHardKeyboards.clear();
	mIm.unregisterInputDeviceListener(this);
	mShowVirtualKeyboardSwitch.setOnPreferenceChangeListener(null);
	unregisterShowVirtualKeyboardSettingsObserver();
	}

	@Override
	public void onInputDeviceAdded(int deviceId) {
	scheduleUpdateHardKeyboards();
	}

	@Override
	public void onInputDeviceRemoved(int deviceId) {
	scheduleUpdateHardKeyboards();
	}

	@Override
	public void onInputDeviceChanged(int deviceId) {
	scheduleUpdateHardKeyboards();
	}

	@Override
	public int getMetricsCategory() {
	return SettingsEnums.PHYSICAL_KEYBOARDS;
	}

	private void scheduleUpdateHardKeyboards() {
	final Context context = getContext();
	ThreadUtils.postOnBackgroundThread(() -> {
	final List<HardKeyboardDeviceInfo> newHardKeyboards = getHardKeyboards(context);
	ThreadUtils.postOnMainThread(() -> updateHardKeyboards(newHardKeyboards));
	});
	}

	private void updateHardKeyboards(@NonNull List<HardKeyboardDeviceInfo> newHardKeyboards) {
	if (Objects.equals(mLastHardKeyboards, newHardKeyboards)) {
	// Nothing has changed. Ignore.
	return;
	}

	// TODO(yukawa): Maybe we should follow the style used in ConnectedDeviceDashboardFragment.

	mLastHardKeyboards.clear();
	mLastHardKeyboards.addAll(newHardKeyboards);

	final PreferenceScreen preferenceScreen = getPreferenceScreen();
	preferenceScreen.removeAll();
	final PreferenceCategory category = new PreferenceCategory(getPrefContext());
	category.setTitle(R.string.builtin_keyboard_settings_title);
	category.setOrder(0);
	preferenceScreen.addPreference(category);

	for (HardKeyboardDeviceInfo hardKeyboardDeviceInfo : newHardKeyboards) {
	// TODO(yukawa): Consider using com.android.settings.widget.GearPreference
	final Preference pref = new Preference(getPrefContext());
	pref.setTitle(hardKeyboardDeviceInfo.mDeviceName);
	pref.setSummary(hardKeyboardDeviceInfo.mLayoutLabel);
	pref.setOnPreferenceClickListener(preference -> {
	showKeyboardLayoutDialog(hardKeyboardDeviceInfo.mDeviceIdentifier);
	return true;
	});
	category.addPreference(pref);
	}

	mKeyboardAssistanceCategory.setOrder(1);
	preferenceScreen.addPreference(mKeyboardAssistanceCategory);
	updateShowVirtualKeyboardSwitch();
	}

	private void showKeyboardLayoutDialog(InputDeviceIdentifier inputDeviceIdentifier) {
	KeyboardLayoutDialogFragment fragment = new KeyboardLayoutDialogFragment(
	inputDeviceIdentifier);
	fragment.setTargetFragment(this, 0);
	fragment.show(getActivity().getSupportFragmentManager(), "keyboardLayout");
	}

	private void registerShowVirtualKeyboardSettingsObserver() {
	unregisterShowVirtualKeyboardSettingsObserver();
	getActivity().getContentResolver().registerContentObserver(
	Secure.getUriFor(Secure.SHOW_IME_WITH_HARD_KEYBOARD),
	false,
	mContentObserver,
	UserHandle.myUserId());
	updateShowVirtualKeyboardSwitch();
	}

	private void unregisterShowVirtualKeyboardSettingsObserver() {
	getActivity().getContentResolver().unregisterContentObserver(mContentObserver);
	}

	private void updateShowVirtualKeyboardSwitch() {
	mShowVirtualKeyboardSwitch.setChecked(
	Secure.getInt(getContentResolver(), Secure.SHOW_IME_WITH_HARD_KEYBOARD, 0) != 0);
	}

	private void toggleKeyboardShortcutsMenu() {
	getActivity().requestShowKeyboardShortcuts();
	}

	private final OnPreferenceChangeListener mShowVirtualKeyboardSwitchPreferenceChangeListener =
	(preference, newValue) -> {
	Secure.putInt(getContentResolver(), Secure.SHOW_IME_WITH_HARD_KEYBOARD,
	((Boolean) newValue) ? 1 : 0);
	return true;
	};

	private final ContentObserver mContentObserver = new ContentObserver(new Handler(true)) {
	@Override
	public void onChange(boolean selfChange) {
	updateShowVirtualKeyboardSwitch();
	}
	};

	@Override
	public void onSetupKeyboardLayouts(InputDeviceIdentifier inputDeviceIdentifier) {
	final Intent intent = new Intent(Intent.ACTION_MAIN);
	intent.setClass(getActivity(), Settings.KeyboardLayoutPickerActivity.class);
	intent.putExtra(KeyboardLayoutPickerFragment.EXTRA_INPUT_DEVICE_IDENTIFIER,
	inputDeviceIdentifier);
	mIntentWaitingForResult = intent;
	startActivityForResult(intent, 0);
	}

	@Override
	public void onActivityResult(int requestCode, int resultCode, Intent data) {
	super.onActivityResult(requestCode, resultCode, data);

	if (mIntentWaitingForResult != null) {
	InputDeviceIdentifier inputDeviceIdentifier = mIntentWaitingForResult
	.getParcelableExtra(KeyboardLayoutPickerFragment.EXTRA_INPUT_DEVICE_IDENTIFIER);
	mIntentWaitingForResult = null;
	showKeyboardLayoutDialog(inputDeviceIdentifier);
	}
	}

	private static String getLayoutLabel(@NonNull InputDevice device,
	@NonNull Context context, @NonNull InputManager im) {
	final String currentLayoutDesc =
	im.getCurrentKeyboardLayoutForInputDevice(device.getIdentifier());
	if (currentLayoutDesc == null) {
	return context.getString(R.string.keyboard_layout_default_label);
	}
	final KeyboardLayout currentLayout = im.getKeyboardLayout(currentLayoutDesc);
	if (currentLayout == null) {
	return context.getString(R.string.keyboard_layout_default_label);
	}
	// If current layout is specified but the layout is null, just return an empty string
	// instead of falling back to R.string.keyboard_layout_default_label.
	return TextUtils.emptyIfNull(currentLayout.getLabel());
	}

	@NonNull
	static List<HardKeyboardDeviceInfo> getHardKeyboards(@NonNull Context context) {
	final List<HardKeyboardDeviceInfo> keyboards = new ArrayList<>();
	final InputManager im = context.getSystemService(InputManager.class);
	if (im == null) {
	return new ArrayList<>();
	}
	for (int deviceId : InputDevice.getDeviceIds()) {
	final InputDevice device = InputDevice.getDevice(deviceId);
	if (device == null \|\| device.isVirtual() \|\| !device.isFullKeyboard()) {
	continue;
	}
	keyboards.add(new HardKeyboardDeviceInfo(
	device.getName(), device.getIdentifier(), getLayoutLabel(device, context, im)));
	}

	// We intentionally don't reuse Comparator because Collator may not be thread-safe.
	final Collator collator = Collator.getInstance();
	keyboards.sort((a, b) -> {
	int result = collator.compare(a.mDeviceName, b.mDeviceName);
	if (result != 0) {
	return result;
	}
	result = a.mDeviceIdentifier.getDescriptor().compareTo(
	b.mDeviceIdentifier.getDescriptor());
	if (result != 0) {
	return result;
	}
	return collator.compare(a.mLayoutLabel, b.mLayoutLabel);
	});
	return keyboards;
	}

	public static final class HardKeyboardDeviceInfo {
	@NonNull
	public final String mDeviceName;
	@NonNull
	public final InputDeviceIdentifier mDeviceIdentifier;
	@NonNull
	public final String mLayoutLabel;

	public HardKeyboardDeviceInfo(
	@Nullable String deviceName,
	@NonNull InputDeviceIdentifier deviceIdentifier,
	@NonNull String layoutLabel) {
	mDeviceName = TextUtils.emptyIfNull(deviceName);
	mDeviceIdentifier = deviceIdentifier;
	mLayoutLabel = layoutLabel;
	}

	@Override
	public boolean equals(Object o) {
	if (o == this) return true;
	if (o == null) return false;

	if (!(o instanceof HardKeyboardDeviceInfo)) return false;

	final HardKeyboardDeviceInfo that = (HardKeyboardDeviceInfo) o;
	if (!TextUtils.equals(mDeviceName, that.mDeviceName)) {
	return false;
	}
	if (!Objects.equals(mDeviceIdentifier, that.mDeviceIdentifier)) {
	return false;
	}
	if (!TextUtils.equals(mLayoutLabel, that.mLayoutLabel)) {
	return false;
	}

	return true;
	}
	}

	public static final Indexable.SearchIndexProvider SEARCH_INDEX_DATA_PROVIDER =
	new BaseSearchIndexProvider() {
	@Override
	public List<SearchIndexableResource> getXmlResourcesToIndex(
	Context context, boolean enabled) {
	final SearchIndexableResource sir = new SearchIndexableResource(context);
	sir.xmlResId = R.xml.physical_keyboard_settings;
	return Arrays.asList(sir);
	}
	};
	}