| /* |
| * Copyright (C) 2013 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.systemui.settings; |
| |
| import android.app.ActivityManager; |
| import android.content.BroadcastReceiver; |
| import android.content.Context; |
| import android.content.Intent; |
| import android.content.IntentFilter; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.function.Consumer; |
| |
| public abstract class CurrentUserTracker { |
| private final UserReceiver mUserReceiver; |
| |
| private Consumer<Integer> mCallback = this::onUserSwitched; |
| |
| public CurrentUserTracker(Context context) { |
| mUserReceiver = UserReceiver.getInstance(context); |
| } |
| |
| public int getCurrentUserId() { |
| return mUserReceiver.getCurrentUserId(); |
| } |
| |
| public void startTracking() { |
| mUserReceiver.addTracker(mCallback); |
| } |
| |
| public void stopTracking() { |
| mUserReceiver.removeTracker(mCallback); |
| } |
| |
| public abstract void onUserSwitched(int newUserId); |
| |
| private static class UserReceiver extends BroadcastReceiver { |
| private static UserReceiver sInstance; |
| |
| private Context mAppContext; |
| private boolean mReceiverRegistered; |
| private int mCurrentUserId; |
| |
| private List<Consumer<Integer>> mCallbacks = new ArrayList<>(); |
| |
| private UserReceiver(Context context) { |
| mAppContext = context.getApplicationContext(); |
| } |
| |
| static UserReceiver getInstance(Context context) { |
| if (sInstance == null) { |
| sInstance = new UserReceiver(context); |
| } |
| return sInstance; |
| } |
| |
| @Override |
| public void onReceive(Context context, Intent intent) { |
| if (Intent.ACTION_USER_SWITCHED.equals(intent.getAction())) { |
| notifyUserSwitched(intent.getIntExtra(Intent.EXTRA_USER_HANDLE, 0)); |
| } |
| } |
| |
| public int getCurrentUserId() { |
| return mCurrentUserId; |
| } |
| |
| private void addTracker(Consumer<Integer> callback) { |
| if (!mCallbacks.contains(callback)) { |
| mCallbacks.add(callback); |
| } |
| if (!mReceiverRegistered) { |
| mCurrentUserId = ActivityManager.getCurrentUser(); |
| IntentFilter filter = new IntentFilter(Intent.ACTION_USER_SWITCHED); |
| mAppContext.registerReceiver(this, filter); |
| mReceiverRegistered = true; |
| } |
| } |
| |
| private void removeTracker(Consumer<Integer> callback) { |
| if (mCallbacks.contains(callback)) { |
| mCallbacks.remove(callback); |
| if (mCallbacks.size() == 0 && mReceiverRegistered) { |
| mAppContext.unregisterReceiver(this); |
| mReceiverRegistered = false; |
| } |
| } |
| } |
| |
| private void notifyUserSwitched(int newUserId) { |
| if (mCurrentUserId != newUserId) { |
| mCurrentUserId = newUserId; |
| for (Consumer<Integer> consumer : mCallbacks) { |
| consumer.accept(newUserId); |
| } |
| } |
| } |
| } |
| } |