1 /* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.support.v7.media; 18 19 import android.content.BroadcastReceiver; 20 import android.content.ComponentName; 21 import android.content.Context; 22 import android.content.Intent; 23 import android.content.IntentFilter; 24 import android.content.pm.PackageManager; 25 import android.content.pm.ResolveInfo; 26 import android.content.pm.ServiceInfo; 27 28 import java.util.ArrayList; 29 import java.util.Collections; 30 31 /** 32 * Watches for media route provider services to be installed. 33 * Adds a provider to the media router for each registered service. 34 * 35 * @see RegisteredMediaRouteProvider 36 */ 37 final class RegisteredMediaRouteProviderWatcher { 38 private final Context mContext; 39 private final MediaRouter mRouter; 40 private final ArrayList<RegisteredMediaRouteProvider> mProviders = 41 new ArrayList<RegisteredMediaRouteProvider>(); 42 private final PackageManager mPackageManager; 43 44 public RegisteredMediaRouteProviderWatcher(Context context, MediaRouter router) { 45 mContext = context; 46 mRouter = router; 47 mPackageManager = context.getPackageManager(); 48 } 49 50 public void start() { 51 IntentFilter filter = new IntentFilter(); 52 filter.addAction(Intent.ACTION_PACKAGE_ADDED); 53 filter.addAction(Intent.ACTION_PACKAGE_REMOVED); 54 filter.addAction(Intent.ACTION_PACKAGE_CHANGED); 55 mContext.registerReceiver(new BroadcastReceiver() { 56 @Override 57 public void onReceive(Context context, Intent intent) { 58 scanPackages(); 59 } 60 }, filter); 61 62 scanPackages(); 63 } 64 65 private void scanPackages() { 66 // Add providers for all new services. 67 // Reorder the list so that providers left at the end will be the ones to remove. 68 int targetIndex = 0; 69 Intent intent = new Intent(MediaRouteProviderService.SERVICE_INTERFACE); 70 for (ResolveInfo resolveInfo : mPackageManager.queryIntentServices(intent, 0)) { 71 ServiceInfo serviceInfo = resolveInfo.serviceInfo; 72 if (serviceInfo != null) { 73 int sourceIndex = findProvider(serviceInfo.packageName, serviceInfo.name); 74 if (sourceIndex < 0) { 75 RegisteredMediaRouteProvider provider = 76 new RegisteredMediaRouteProvider(mContext, 77 new ComponentName(serviceInfo.packageName, serviceInfo.name)); 78 provider.start(); 79 mProviders.add(targetIndex++, provider); 80 mRouter.addProvider(provider); 81 } else if (sourceIndex >= targetIndex) { 82 RegisteredMediaRouteProvider provider = mProviders.get(sourceIndex); 83 provider.rebindIfDisconnected(); 84 Collections.swap(mProviders, sourceIndex, targetIndex++); 85 } 86 } 87 } 88 89 // Remove providers for missing services. 90 if (targetIndex < mProviders.size()) { 91 for (int i = mProviders.size() - 1; i >= targetIndex; i--) { 92 RegisteredMediaRouteProvider provider = mProviders.get(i); 93 mRouter.removeProvider(provider); 94 mProviders.remove(provider); 95 provider.stop(); 96 } 97 } 98 } 99 100 private int findProvider(String packageName, String className) { 101 int count = mProviders.size(); 102 for (int i = 0; i < count; i++) { 103 RegisteredMediaRouteProvider provider = mProviders.get(i); 104 if (provider.hasComponentName(packageName, className)) { 105 return i; 106 } 107 } 108 return -1; 109 } 110 } 111
