| /* |
| * Copyright (C) 2011 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 android.support.v4.content; |
| |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.Set; |
| |
| import android.content.BroadcastReceiver; |
| import android.content.Context; |
| import android.content.Intent; |
| import android.content.IntentFilter; |
| import android.net.Uri; |
| import android.os.Handler; |
| import android.os.Message; |
| import android.util.Log; |
| |
| /** |
| * Helper to register for and send broadcasts of Intents to local objects |
| * within your process. This is has a number of advantages over sending |
| * global broadcasts with {@link android.content.Context#sendBroadcast}: |
| * <ul> |
| * <li> You know that the data you are broadcasting won't leave your app, so |
| * don't need to worry about leaking private data. |
| * <li> It is not possible for other applications to send these broadcasts to |
| * your app, so you don't need to worry about having security holes they can |
| * exploit. |
| * <li> It is more efficient than sending a global broadcast through the |
| * system. |
| * </ul> |
| */ |
| public class LocalBroadcastManager { |
| private static class ReceiverRecord { |
| final IntentFilter filter; |
| final BroadcastReceiver receiver; |
| boolean broadcasting; |
| |
| ReceiverRecord(IntentFilter _filter, BroadcastReceiver _receiver) { |
| filter = _filter; |
| receiver = _receiver; |
| } |
| |
| @Override |
| public String toString() { |
| StringBuilder builder = new StringBuilder(128); |
| builder.append("Receiver{"); |
| builder.append(receiver); |
| builder.append(" filter="); |
| builder.append(filter); |
| builder.append("}"); |
| return builder.toString(); |
| } |
| } |
| |
| private static class BroadcastRecord { |
| final Intent intent; |
| final ArrayList<ReceiverRecord> receivers; |
| |
| BroadcastRecord(Intent _intent, ArrayList<ReceiverRecord> _receivers) { |
| intent = _intent; |
| receivers = _receivers; |
| } |
| } |
| |
| private static final String TAG = "LocalBroadcastManager"; |
| private static final boolean DEBUG = false; |
| |
| private final Context mAppContext; |
| |
| private final HashMap<BroadcastReceiver, ArrayList<IntentFilter>> mReceivers |
| = new HashMap<BroadcastReceiver, ArrayList<IntentFilter>>(); |
| private final HashMap<String, ArrayList<ReceiverRecord>> mActions |
| = new HashMap<String, ArrayList<ReceiverRecord>>(); |
| |
| private final ArrayList<BroadcastRecord> mPendingBroadcasts |
| = new ArrayList<BroadcastRecord>(); |
| |
| static final int MSG_EXEC_PENDING_BROADCASTS = 1; |
| |
| private final Handler mHandler; |
| |
| private static final Object mLock = new Object(); |
| private static LocalBroadcastManager mInstance; |
| |
| public static LocalBroadcastManager getInstance(Context context) { |
| synchronized (mLock) { |
| if (mInstance == null) { |
| mInstance = new LocalBroadcastManager(context.getApplicationContext()); |
| } |
| return mInstance; |
| } |
| } |
| |
| private LocalBroadcastManager(Context context) { |
| mAppContext = context; |
| mHandler = new Handler(context.getMainLooper()) { |
| |
| @Override |
| public void handleMessage(Message msg) { |
| switch (msg.what) { |
| case MSG_EXEC_PENDING_BROADCASTS: |
| executePendingBroadcasts(); |
| break; |
| default: |
| super.handleMessage(msg); |
| } |
| } |
| }; |
| } |
| |
| /** |
| * Register a receive for any local broadcasts that match the given IntentFilter. |
| * |
| * @param receiver The BroadcastReceiver to handle the broadcast. |
| * @param filter Selects the Intent broadcasts to be received. |
| * |
| * @see #unregisterReceiver |
| */ |
| public void registerReceiver(BroadcastReceiver receiver, IntentFilter filter) { |
| synchronized (mReceivers) { |
| ReceiverRecord entry = new ReceiverRecord(filter, receiver); |
| ArrayList<IntentFilter> filters = mReceivers.get(receiver); |
| if (filters == null) { |
| filters = new ArrayList<IntentFilter>(1); |
| mReceivers.put(receiver, filters); |
| } |
| filters.add(filter); |
| for (int i=0; i<filter.countActions(); i++) { |
| String action = filter.getAction(i); |
| ArrayList<ReceiverRecord> entries = mActions.get(action); |
| if (entries == null) { |
| entries = new ArrayList<ReceiverRecord>(1); |
| mActions.put(action, entries); |
| } |
| entries.add(entry); |
| } |
| } |
| } |
| |
| /** |
| * Unregister a previously registered BroadcastReceiver. <em>All</em> |
| * filters that have been registered for this BroadcastReceiver will be |
| * removed. |
| * |
| * @param receiver The BroadcastReceiver to unregister. |
| * |
| * @see #registerReceiver |
| */ |
| public void unregisterReceiver(BroadcastReceiver receiver) { |
| synchronized (mReceivers) { |
| ArrayList<IntentFilter> filters = mReceivers.remove(receiver); |
| if (filters == null) { |
| return; |
| } |
| for (int i=0; i<filters.size(); i++) { |
| IntentFilter filter = filters.get(i); |
| for (int j=0; j<filter.countActions(); j++) { |
| String action = filter.getAction(j); |
| ArrayList<ReceiverRecord> receivers = mActions.get(action); |
| if (receivers != null) { |
| for (int k=0; k<receivers.size(); k++) { |
| if (receivers.get(k).receiver == receiver) { |
| receivers.remove(k); |
| k--; |
| } |
| } |
| if (receivers.size() <= 0) { |
| mActions.remove(action); |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| /** |
| * Broadcast the given intent to all interested BroadcastReceivers. This |
| * call is asynchronous; it returns immediately, and you will continue |
| * executing while the receivers are run. |
| * |
| * @param intent The Intent to broadcast; all receivers matching this |
| * Intent will receive the broadcast. |
| * |
| * @see #registerReceiver |
| */ |
| public boolean sendBroadcast(Intent intent) { |
| synchronized (mReceivers) { |
| final String action = intent.getAction(); |
| final String type = intent.resolveTypeIfNeeded( |
| mAppContext.getContentResolver()); |
| final Uri data = intent.getData(); |
| final String scheme = intent.getScheme(); |
| final Set<String> categories = intent.getCategories(); |
| |
| final boolean debug = DEBUG || |
| ((intent.getFlags() & Intent.FLAG_DEBUG_LOG_RESOLUTION) != 0); |
| if (debug) Log.v( |
| TAG, "Resolving type " + type + " scheme " + scheme |
| + " of intent " + intent); |
| |
| ArrayList<ReceiverRecord> entries = mActions.get(intent.getAction()); |
| if (entries != null) { |
| if (debug) Log.v(TAG, "Action list: " + entries); |
| |
| ArrayList<ReceiverRecord> receivers = null; |
| for (int i=0; i<entries.size(); i++) { |
| ReceiverRecord receiver = entries.get(i); |
| if (debug) Log.v(TAG, "Matching against filter " + receiver.filter); |
| |
| if (receiver.broadcasting) { |
| if (debug) { |
| Log.v(TAG, " Filter's target already added"); |
| } |
| continue; |
| } |
| |
| int match = receiver.filter.match(action, type, scheme, data, |
| categories, "LocalBroadcastManager"); |
| if (match >= 0) { |
| if (debug) Log.v(TAG, " Filter matched! match=0x" + |
| Integer.toHexString(match)); |
| if (receivers == null) { |
| receivers = new ArrayList<ReceiverRecord>(); |
| } |
| receivers.add(receiver); |
| receiver.broadcasting = true; |
| } else { |
| if (debug) { |
| String reason; |
| switch (match) { |
| case IntentFilter.NO_MATCH_ACTION: reason = "action"; break; |
| case IntentFilter.NO_MATCH_CATEGORY: reason = "category"; break; |
| case IntentFilter.NO_MATCH_DATA: reason = "data"; break; |
| case IntentFilter.NO_MATCH_TYPE: reason = "type"; break; |
| default: reason = "unknown reason"; break; |
| } |
| Log.v(TAG, " Filter did not match: " + reason); |
| } |
| } |
| } |
| |
| if (receivers != null) { |
| for (int i=0; i<receivers.size(); i++) { |
| receivers.get(i).broadcasting = false; |
| } |
| mPendingBroadcasts.add(new BroadcastRecord(intent, receivers)); |
| if (!mHandler.hasMessages(MSG_EXEC_PENDING_BROADCASTS)) { |
| mHandler.sendEmptyMessage(MSG_EXEC_PENDING_BROADCASTS); |
| } |
| return true; |
| } |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Like {@link #sendBroadcast(Intent)}, but if there are any receivers for |
| * the Intent this function will block and immediately dispatch them before |
| * returning. |
| */ |
| public void sendBroadcastSync(Intent intent) { |
| if (sendBroadcast(intent)) { |
| executePendingBroadcasts(); |
| } |
| } |
| |
| private void executePendingBroadcasts() { |
| while (true) { |
| BroadcastRecord[] brs = null; |
| synchronized (mReceivers) { |
| final int N = mPendingBroadcasts.size(); |
| if (N <= 0) { |
| return; |
| } |
| brs = new BroadcastRecord[N]; |
| mPendingBroadcasts.toArray(brs); |
| mPendingBroadcasts.clear(); |
| } |
| for (int i=0; i<brs.length; i++) { |
| BroadcastRecord br = brs[i]; |
| for (int j=0; j<br.receivers.size(); j++) { |
| br.receivers.get(j).receiver.onReceive(mAppContext, br.intent); |
| } |
| } |
| } |
| } |
| } |