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 17package android.support.v7.media; 18 19import android.content.BroadcastReceiver; 20import android.content.ComponentName; 21import android.content.Context; 22import android.content.Intent; 23import android.content.IntentFilter; 24import android.content.pm.PackageManager; 25import android.content.pm.ResolveInfo; 26import android.content.pm.ServiceInfo; 27import android.os.Handler; 28 29import java.util.ArrayList; 30import java.util.Collections; 31 32/** 33 * Watches for media route provider services to be installed. 34 * Adds a provider to the media router for each registered service. 35 * 36 * @see RegisteredMediaRouteProvider 37 */ 38final class RegisteredMediaRouteProviderWatcher { 39 private final Context mContext; 40 private final Callback mCallback; 41 private final Handler mHandler; 42 private final PackageManager mPackageManager; 43 44 private final ArrayList<RegisteredMediaRouteProvider> mProviders = 45 new ArrayList<RegisteredMediaRouteProvider>(); 46 private boolean mRunning; 47 48 public RegisteredMediaRouteProviderWatcher(Context context, Callback callback) { 49 mContext = context; 50 mCallback = callback; 51 mHandler = new Handler(); 52 mPackageManager = context.getPackageManager(); 53 } 54 55 public void start() { 56 if (!mRunning) { 57 mRunning = true; 58 59 IntentFilter filter = new IntentFilter(); 60 filter.addAction(Intent.ACTION_PACKAGE_ADDED); 61 filter.addAction(Intent.ACTION_PACKAGE_REMOVED); 62 filter.addAction(Intent.ACTION_PACKAGE_CHANGED); 63 filter.addAction(Intent.ACTION_PACKAGE_REPLACED); 64 filter.addAction(Intent.ACTION_PACKAGE_RESTARTED); 65 filter.addDataScheme("package"); 66 mContext.registerReceiver(mScanPackagesReceiver, filter, null, mHandler); 67 68 // Scan packages. 69 // Also has the side-effect of restarting providers if needed. 70 mHandler.post(mScanPackagesRunnable); 71 } 72 } 73 74 public void stop() { 75 if (mRunning) { 76 mRunning = false; 77 78 mContext.unregisterReceiver(mScanPackagesReceiver); 79 mHandler.removeCallbacks(mScanPackagesRunnable); 80 81 // Stop all providers. 82 for (int i = mProviders.size() - 1; i >= 0; i--) { 83 mProviders.get(i).stop(); 84 } 85 } 86 } 87 88 private void scanPackages() { 89 if (!mRunning) { 90 return; 91 } 92 93 // Add providers for all new services. 94 // Reorder the list so that providers left at the end will be the ones to remove. 95 int targetIndex = 0; 96 Intent intent = new Intent(MediaRouteProviderService.SERVICE_INTERFACE); 97 for (ResolveInfo resolveInfo : mPackageManager.queryIntentServices(intent, 0)) { 98 ServiceInfo serviceInfo = resolveInfo.serviceInfo; 99 if (serviceInfo != null) { 100 int sourceIndex = findProvider(serviceInfo.packageName, serviceInfo.name); 101 if (sourceIndex < 0) { 102 RegisteredMediaRouteProvider provider = 103 new RegisteredMediaRouteProvider(mContext, 104 new ComponentName(serviceInfo.packageName, serviceInfo.name)); 105 provider.start(); 106 mProviders.add(targetIndex++, provider); 107 mCallback.addProvider(provider); 108 } else if (sourceIndex >= targetIndex) { 109 RegisteredMediaRouteProvider provider = mProviders.get(sourceIndex); 110 provider.start(); // restart the provider if needed 111 provider.rebindIfDisconnected(); 112 Collections.swap(mProviders, sourceIndex, targetIndex++); 113 } 114 } 115 } 116 117 // Remove providers for missing services. 118 if (targetIndex < mProviders.size()) { 119 for (int i = mProviders.size() - 1; i >= targetIndex; i--) { 120 RegisteredMediaRouteProvider provider = mProviders.get(i); 121 mCallback.removeProvider(provider); 122 mProviders.remove(provider); 123 provider.stop(); 124 } 125 } 126 } 127 128 private int findProvider(String packageName, String className) { 129 int count = mProviders.size(); 130 for (int i = 0; i < count; i++) { 131 RegisteredMediaRouteProvider provider = mProviders.get(i); 132 if (provider.hasComponentName(packageName, className)) { 133 return i; 134 } 135 } 136 return -1; 137 } 138 139 private final BroadcastReceiver mScanPackagesReceiver = new BroadcastReceiver() { 140 @Override 141 public void onReceive(Context context, Intent intent) { 142 scanPackages(); 143 } 144 }; 145 146 private final Runnable mScanPackagesRunnable = new Runnable() { 147 @Override 148 public void run() { 149 scanPackages(); 150 } 151 }; 152 153 public interface Callback { 154 void addProvider(MediaRouteProvider provider); 155 void removeProvider(MediaRouteProvider provider); 156 } 157} 158