content: /**
   * Copyright (c) 2018 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.launcher3;
  
  import static com.android.launcher3.PinnedAppListViewModel.PINNED_APPS_KEY;
  
  import android.app.Application;
  import android.content.ComponentName;
  import android.content.Context;
  import android.content.Intent;
  import android.content.SharedPreferences;
  import android.content.pm.PackageManager;
  import android.content.pm.ResolveInfo;
  import android.os.AsyncTask;
  
  import androidx.lifecycle.AndroidViewModel;
  import androidx.lifecycle.LiveData;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Set;
  
  /**
   * A view model that provides a list of activities that were pinned by user to always display on
   * home screen.
   * The pinned activities are stored in {@link SharedPreferences} to keep the sample simple :).
   */
  public class PinnedAppListViewModel extends AndroidViewModel {
  
      final static String PINNED_APPS_KEY = "pinned_apps";
  
      private final PinnedAppListLiveData mLiveData;
  
      public PinnedAppListViewModel(Application application) {
          super(application);
          mLiveData = new PinnedAppListLiveData(application);
      }
  
      public LiveData<List<AppEntry>> getPinnedAppList() {
          return mLiveData;
      }
  }
  
  class PinnedAppListLiveData extends LiveData<List<AppEntry>> {
  
      private final Context mContext;
      private final PackageManager mPackageManager;
      // Store listener reference, so it won't be GC-ed.
      private final SharedPreferences.OnSharedPreferenceChangeListener mChangeListener;
      private int mCurrentDataVersion;
  
      public PinnedAppListLiveData(Context context) {
          mContext = context;
          mPackageManager = context.getPackageManager();
  
          final SharedPreferences prefs = context.getSharedPreferences(PINNED_APPS_KEY, 0);
          mChangeListener = (preferences, key) -> {
              loadData();
          };
          prefs.registerOnSharedPreferenceChangeListener(mChangeListener);
  
          loadData();
      }
  
      private void loadData() {
          final int loadDataVersion = ++mCurrentDataVersion;
  
          new AsyncTask<Void, Void, List<AppEntry>>() {
              @Override
              protected List<AppEntry> doInBackground(Void... voids) {
                  List<AppEntry> entries = new ArrayList<>();
  
                  final SharedPreferences sp = mContext.getSharedPreferences(PINNED_APPS_KEY, 0);
                  final Set<String> pinnedAppsComponents = sp.getStringSet(PINNED_APPS_KEY, null);
                  if (pinnedAppsComponents == null) {
                      return null;
                  }
  
                  for (String componentString : pinnedAppsComponents) {
                      final Intent mainIntent = new Intent(Intent.ACTION_MAIN, null);
                      mainIntent.setComponent(ComponentName.unflattenFromString(componentString));
                      mainIntent.addCategory(Intent.CATEGORY_LAUNCHER);
  
                      final List<ResolveInfo> apps = mPackageManager.queryIntentActivities(mainIntent,
                              PackageManager.GET_META_DATA);
  
                      if (apps != null) {
                          for (ResolveInfo app : apps) {
                              final AppEntry entry = new AppEntry(app, mPackageManager);
                              entries.add(entry);
                          }
                      }
                  }
  
                  return entries;
              }
  
              @Override
              protected void onPostExecute(List<AppEntry> data) {
                  if (mCurrentDataVersion == loadDataVersion) {
                      setValue(data);
                  }
              }
          }.execute();
      }
  }