1/*
2 * Copyright (C) 2006 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.content;
18
19import android.app.ActivityManagerNative;
20import android.app.ActivityThread;
21import android.app.IActivityManager;
22import android.app.QueuedWork;
23import android.os.Bundle;
24import android.os.IBinder;
25import android.os.RemoteException;
26import android.util.Log;
27import android.util.Slog;
28
29/**
30 * Base class for code that will receive intents sent by sendBroadcast().
31 *
32 * <p>If you don't need to send broadcasts across applications, consider using
33 * this class with {@link android.support.v4.content.LocalBroadcastManager} instead
34 * of the more general facilities described below.  This will give you a much
35 * more efficient implementation (no cross-process communication needed) and allow
36 * you to avoid thinking about any security issues related to other applications
37 * being able to receive or send your broadcasts.
38 *
39 * <p>You can either dynamically register an instance of this class with
40 * {@link Context#registerReceiver Context.registerReceiver()}
41 * or statically publish an implementation through the
42 * {@link android.R.styleable#AndroidManifestReceiver &lt;receiver&gt;}
43 * tag in your <code>AndroidManifest.xml</code>.
44 *
45 * <p><em><strong>Note:</strong></em>
46 * &nbsp;&nbsp;&nbsp;If registering a receiver in your
47 * {@link android.app.Activity#onResume() Activity.onResume()}
48 * implementation, you should unregister it in
49 * {@link android.app.Activity#onPause() Activity.onPause()}.
50 * (You won't receive intents when paused,
51 * and this will cut down on unnecessary system overhead). Do not unregister in
52 * {@link android.app.Activity#onSaveInstanceState(android.os.Bundle) Activity.onSaveInstanceState()},
53 * because this won't be called if the user moves back in the history
54 * stack.
55 *
56 * <p>There are two major classes of broadcasts that can be received:</p>
57 * <ul>
58 * <li> <b>Normal broadcasts</b> (sent with {@link Context#sendBroadcast(Intent)
59 * Context.sendBroadcast}) are completely asynchronous.  All receivers of the
60 * broadcast are run in an undefined order, often at the same time.  This is
61 * more efficient, but means that receivers cannot use the result or abort
62 * APIs included here.
63 * <li> <b>Ordered broadcasts</b> (sent with {@link Context#sendOrderedBroadcast(Intent, String)
64 * Context.sendOrderedBroadcast}) are delivered to one receiver at a time.
65 * As each receiver executes in turn, it can propagate a result to the next
66 * receiver, or it can completely abort the broadcast so that it won't be passed
67 * to other receivers.  The order receivers run in can be controlled with the
68 * {@link android.R.styleable#AndroidManifestIntentFilter_priority
69 * android:priority} attribute of the matching intent-filter; receivers with
70 * the same priority will be run in an arbitrary order.
71 * </ul>
72 *
73 * <p>Even in the case of normal broadcasts, the system may in some
74 * situations revert to delivering the broadcast one receiver at a time.  In
75 * particular, for receivers that may require the creation of a process, only
76 * one will be run at a time to avoid overloading the system with new processes.
77 * In this situation, however, the non-ordered semantics hold: these receivers still
78 * cannot return results or abort their broadcast.</p>
79 *
80 * <p>Note that, although the Intent class is used for sending and receiving
81 * these broadcasts, the Intent broadcast mechanism here is completely separate
82 * from Intents that are used to start Activities with
83 * {@link Context#startActivity Context.startActivity()}.
84 * There is no way for a BroadcastReceiver
85 * to see or capture Intents used with startActivity(); likewise, when
86 * you broadcast an Intent, you will never find or start an Activity.
87 * These two operations are semantically very different: starting an
88 * Activity with an Intent is a foreground operation that modifies what the
89 * user is currently interacting with; broadcasting an Intent is a background
90 * operation that the user is not normally aware of.
91 *
92 * <p>The BroadcastReceiver class (when launched as a component through
93 * a manifest's {@link android.R.styleable#AndroidManifestReceiver &lt;receiver&gt;}
94 * tag) is an important part of an
95 * <a href="{@docRoot}guide/topics/fundamentals.html#lcycles">application's overall lifecycle</a>.</p>
96 *
97 * <p>Topics covered here:
98 * <ol>
99 * <li><a href="#Security">Security</a>
100 * <li><a href="#ReceiverLifecycle">Receiver Lifecycle</a>
101 * <li><a href="#ProcessLifecycle">Process Lifecycle</a>
102 * </ol>
103 *
104 * <div class="special reference">
105 * <h3>Developer Guides</h3>
106 * <p>For information about how to use this class to receive and resolve intents, read the
107 * <a href="{@docRoot}guide/topics/intents/intents-filters.html">Intents and Intent Filters</a>
108 * developer guide.</p>
109 * </div>
110 *
111 * <a name="Security"></a>
112 * <h3>Security</h3>
113 *
114 * <p>Receivers used with the {@link Context} APIs are by their nature a
115 * cross-application facility, so you must consider how other applications
116 * may be able to abuse your use of them.  Some things to consider are:
117 *
118 * <ul>
119 * <li><p>The Intent namespace is global.  Make sure that Intent action names and
120 * other strings are written in a namespace you own, or else you may inadvertently
121 * conflict with other applications.
122 * <li><p>When you use {@link Context#registerReceiver(BroadcastReceiver, IntentFilter)},
123 * <em>any</em> application may send broadcasts to that registered receiver.  You can
124 * control who can send broadcasts to it through permissions described below.
125 * <li><p>When you publish a receiver in your application's manifest and specify
126 * intent-filters for it, any other application can send broadcasts to it regardless
127 * of the filters you specify.  To prevent others from sending to it, make it
128 * unavailable to them with <code>android:exported="false"</code>.
129 * <li><p>When you use {@link Context#sendBroadcast(Intent)} or related methods,
130 * normally any other application can receive these broadcasts.  You can control who
131 * can receive such broadcasts through permissions described below.  Alternatively,
132 * starting with {@link android.os.Build.VERSION_CODES#ICE_CREAM_SANDWICH}, you
133 * can also safely restrict the broadcast to a single application with
134 * {@link Intent#setPackage(String) Intent.setPackage}
135 * </ul>
136 *
137 * <p>None of these issues exist when using
138 * {@link android.support.v4.content.LocalBroadcastManager}, since intents
139 * broadcast it never go outside of the current process.
140 *
141 * <p>Access permissions can be enforced by either the sender or receiver
142 * of a broadcast.
143 *
144 * <p>To enforce a permission when sending, you supply a non-null
145 * <var>permission</var> argument to
146 * {@link Context#sendBroadcast(Intent, String)} or
147 * {@link Context#sendOrderedBroadcast(Intent, String, BroadcastReceiver, android.os.Handler, int, String, Bundle)}.
148 * Only receivers who have been granted this permission
149 * (by requesting it with the
150 * {@link android.R.styleable#AndroidManifestUsesPermission &lt;uses-permission&gt;}
151 * tag in their <code>AndroidManifest.xml</code>) will be able to receive
152 * the broadcast.
153 *
154 * <p>To enforce a permission when receiving, you supply a non-null
155 * <var>permission</var> when registering your receiver -- either when calling
156 * {@link Context#registerReceiver(BroadcastReceiver, IntentFilter, String, android.os.Handler)}
157 * or in the static
158 * {@link android.R.styleable#AndroidManifestReceiver &lt;receiver&gt;}
159 * tag in your <code>AndroidManifest.xml</code>.  Only broadcasters who have
160 * been granted this permission (by requesting it with the
161 * {@link android.R.styleable#AndroidManifestUsesPermission &lt;uses-permission&gt;}
162 * tag in their <code>AndroidManifest.xml</code>) will be able to send an
163 * Intent to the receiver.
164 *
165 * <p>See the <a href="{@docRoot}guide/topics/security/security.html">Security and Permissions</a>
166 * document for more information on permissions and security in general.
167 *
168 * <a name="ReceiverLifecycle"></a>
169 * <h3>Receiver Lifecycle</h3>
170 *
171 * <p>A BroadcastReceiver object is only valid for the duration of the call
172 * to {@link #onReceive}.  Once your code returns from this function,
173 * the system considers the object to be finished and no longer active.
174 *
175 * <p>This has important repercussions to what you can do in an
176 * {@link #onReceive} implementation: anything that requires asynchronous
177 * operation is not available, because you will need to return from the
178 * function to handle the asynchronous operation, but at that point the
179 * BroadcastReceiver is no longer active and thus the system is free to kill
180 * its process before the asynchronous operation completes.
181 *
182 * <p>In particular, you may <i>not</i> show a dialog or bind to a service from
183 * within a BroadcastReceiver.  For the former, you should instead use the
184 * {@link android.app.NotificationManager} API.  For the latter, you can
185 * use {@link android.content.Context#startService Context.startService()} to
186 * send a command to the service.
187 *
188 * <a name="ProcessLifecycle"></a>
189 * <h3>Process Lifecycle</h3>
190 *
191 * <p>A process that is currently executing a BroadcastReceiver (that is,
192 * currently running the code in its {@link #onReceive} method) is
193 * considered to be a foreground process and will be kept running by the
194 * system except under cases of extreme memory pressure.
195 *
196 * <p>Once you return from onReceive(), the BroadcastReceiver is no longer
197 * active, and its hosting process is only as important as any other application
198 * components that are running in it.  This is especially important because if
199 * that process was only hosting the BroadcastReceiver (a common case for
200 * applications that the user has never or not recently interacted with), then
201 * upon returning from onReceive() the system will consider its process
202 * to be empty and aggressively kill it so that resources are available for other
203 * more important processes.
204 *
205 * <p>This means that for longer-running operations you will often use
206 * a {@link android.app.Service} in conjunction with a BroadcastReceiver to keep
207 * the containing process active for the entire time of your operation.
208 */
209public abstract class BroadcastReceiver {
210    private PendingResult mPendingResult;
211    private boolean mDebugUnregister;
212
213    /**
214     * State for a result that is pending for a broadcast receiver.  Returned
215     * by {@link BroadcastReceiver#goAsync() goAsync()}
216     * while in {@link BroadcastReceiver#onReceive BroadcastReceiver.onReceive()}.
217     * This allows you to return from onReceive() without having the broadcast
218     * terminate; you must call {@link #finish()} once you are done with the
219     * broadcast.  This allows you to process the broadcast off of the main
220     * thread of your app.
221     *
222     * <p>Note on threading: the state inside of this class is not itself
223     * thread-safe, however you can use it from any thread if you properly
224     * sure that you do not have races.  Typically this means you will hand
225     * the entire object to another thread, which will be solely responsible
226     * for setting any results and finally calling {@link #finish()}.
227     */
228    public static class PendingResult {
229        /** @hide */
230        public static final int TYPE_COMPONENT = 0;
231        /** @hide */
232        public static final int TYPE_REGISTERED = 1;
233        /** @hide */
234        public static final int TYPE_UNREGISTERED = 2;
235
236        final int mType;
237        final boolean mOrderedHint;
238        final boolean mInitialStickyHint;
239        final IBinder mToken;
240        final int mSendingUser;
241
242        int mResultCode;
243        String mResultData;
244        Bundle mResultExtras;
245        boolean mAbortBroadcast;
246        boolean mFinished;
247
248        /** @hide */
249        public PendingResult(int resultCode, String resultData, Bundle resultExtras,
250                int type, boolean ordered, boolean sticky, IBinder token, int userId) {
251            mResultCode = resultCode;
252            mResultData = resultData;
253            mResultExtras = resultExtras;
254            mType = type;
255            mOrderedHint = ordered;
256            mInitialStickyHint = sticky;
257            mToken = token;
258            mSendingUser = userId;
259        }
260
261        /**
262         * Version of {@link BroadcastReceiver#setResultCode(int)
263         * BroadcastReceiver.setResultCode(int)} for
264         * asynchronous broadcast handling.
265         */
266        public final void setResultCode(int code) {
267            checkSynchronousHint();
268            mResultCode = code;
269        }
270
271        /**
272         * Version of {@link BroadcastReceiver#getResultCode()
273         * BroadcastReceiver.getResultCode()} for
274         * asynchronous broadcast handling.
275         */
276        public final int getResultCode() {
277            return mResultCode;
278        }
279
280        /**
281         * Version of {@link BroadcastReceiver#setResultData(String)
282         * BroadcastReceiver.setResultData(String)} for
283         * asynchronous broadcast handling.
284         */
285        public final void setResultData(String data) {
286            checkSynchronousHint();
287            mResultData = data;
288        }
289
290        /**
291         * Version of {@link BroadcastReceiver#getResultData()
292         * BroadcastReceiver.getResultData()} for
293         * asynchronous broadcast handling.
294         */
295        public final String getResultData() {
296            return mResultData;
297        }
298
299        /**
300         * Version of {@link BroadcastReceiver#setResultExtras(Bundle)
301         * BroadcastReceiver.setResultExtras(Bundle)} for
302         * asynchronous broadcast handling.
303         */
304        public final void setResultExtras(Bundle extras) {
305            checkSynchronousHint();
306            mResultExtras = extras;
307        }
308
309        /**
310         * Version of {@link BroadcastReceiver#getResultExtras(boolean)
311         * BroadcastReceiver.getResultExtras(boolean)} for
312         * asynchronous broadcast handling.
313         */
314        public final Bundle getResultExtras(boolean makeMap) {
315            Bundle e = mResultExtras;
316            if (!makeMap) return e;
317            if (e == null) mResultExtras = e = new Bundle();
318            return e;
319        }
320
321        /**
322         * Version of {@link BroadcastReceiver#setResult(int, String, Bundle)
323         * BroadcastReceiver.setResult(int, String, Bundle)} for
324         * asynchronous broadcast handling.
325         */
326        public final void setResult(int code, String data, Bundle extras) {
327            checkSynchronousHint();
328            mResultCode = code;
329            mResultData = data;
330            mResultExtras = extras;
331        }
332
333        /**
334         * Version of {@link BroadcastReceiver#getAbortBroadcast()
335         * BroadcastReceiver.getAbortBroadcast()} for
336         * asynchronous broadcast handling.
337         */
338        public final boolean getAbortBroadcast() {
339            return mAbortBroadcast;
340        }
341
342        /**
343         * Version of {@link BroadcastReceiver#abortBroadcast()
344         * BroadcastReceiver.abortBroadcast()} for
345         * asynchronous broadcast handling.
346         */
347        public final void abortBroadcast() {
348            checkSynchronousHint();
349            mAbortBroadcast = true;
350        }
351
352        /**
353         * Version of {@link BroadcastReceiver#clearAbortBroadcast()
354         * BroadcastReceiver.clearAbortBroadcast()} for
355         * asynchronous broadcast handling.
356         */
357        public final void clearAbortBroadcast() {
358            mAbortBroadcast = false;
359        }
360
361        /**
362         * Finish the broadcast.  The current result will be sent and the
363         * next broadcast will proceed.
364         */
365        public final void finish() {
366            if (mType == TYPE_COMPONENT) {
367                final IActivityManager mgr = ActivityManagerNative.getDefault();
368                if (QueuedWork.hasPendingWork()) {
369                    // If this is a broadcast component, we need to make sure any
370                    // queued work is complete before telling AM we are done, so
371                    // we don't have our process killed before that.  We now know
372                    // there is pending work; put another piece of work at the end
373                    // of the list to finish the broadcast, so we don't block this
374                    // thread (which may be the main thread) to have it finished.
375                    //
376                    // Note that we don't need to use QueuedWork.add() with the
377                    // runnable, since we know the AM is waiting for us until the
378                    // executor gets to it.
379                    QueuedWork.singleThreadExecutor().execute( new Runnable() {
380                        @Override public void run() {
381                            if (ActivityThread.DEBUG_BROADCAST) Slog.i(ActivityThread.TAG,
382                                    "Finishing broadcast after work to component " + mToken);
383                            sendFinished(mgr);
384                        }
385                    });
386                } else {
387                    if (ActivityThread.DEBUG_BROADCAST) Slog.i(ActivityThread.TAG,
388                            "Finishing broadcast to component " + mToken);
389                    sendFinished(mgr);
390                }
391            } else if (mOrderedHint && mType != TYPE_UNREGISTERED) {
392                if (ActivityThread.DEBUG_BROADCAST) Slog.i(ActivityThread.TAG,
393                        "Finishing broadcast to " + mToken);
394                final IActivityManager mgr = ActivityManagerNative.getDefault();
395                sendFinished(mgr);
396            }
397        }
398
399        /** @hide */
400        public void setExtrasClassLoader(ClassLoader cl) {
401            if (mResultExtras != null) {
402                mResultExtras.setClassLoader(cl);
403            }
404        }
405
406        /** @hide */
407        public void sendFinished(IActivityManager am) {
408            synchronized (this) {
409                if (mFinished) {
410                    throw new IllegalStateException("Broadcast already finished");
411                }
412                mFinished = true;
413
414                try {
415                    if (mResultExtras != null) {
416                        mResultExtras.setAllowFds(false);
417                    }
418                    if (mOrderedHint) {
419                        am.finishReceiver(mToken, mResultCode, mResultData, mResultExtras,
420                                mAbortBroadcast);
421                    } else {
422                        // This broadcast was sent to a component; it is not ordered,
423                        // but we still need to tell the activity manager we are done.
424                        am.finishReceiver(mToken, 0, null, null, false);
425                    }
426                } catch (RemoteException ex) {
427                }
428            }
429        }
430
431        /** @hide */
432        public int getSendingUserId() {
433            return mSendingUser;
434        }
435
436        void checkSynchronousHint() {
437            // Note that we don't assert when receiving the initial sticky value,
438            // since that may have come from an ordered broadcast.  We'll catch
439            // them later when the real broadcast happens again.
440            if (mOrderedHint || mInitialStickyHint) {
441                return;
442            }
443            RuntimeException e = new RuntimeException(
444                    "BroadcastReceiver trying to return result during a non-ordered broadcast");
445            e.fillInStackTrace();
446            Log.e("BroadcastReceiver", e.getMessage(), e);
447        }
448    }
449
450    public BroadcastReceiver() {
451    }
452
453    /**
454     * This method is called when the BroadcastReceiver is receiving an Intent
455     * broadcast.  During this time you can use the other methods on
456     * BroadcastReceiver to view/modify the current result values.  This method
457     * is always called within the main thread of its process, unless you
458     * explicitly asked for it to be scheduled on a different thread using
459     * {@link android.content.Context#registerReceiver(BroadcastReceiver,
460     * IntentFilter, String, android.os.Handler)}. When it runs on the main
461     * thread you should
462     * never perform long-running operations in it (there is a timeout of
463     * 10 seconds that the system allows before considering the receiver to
464     * be blocked and a candidate to be killed). You cannot launch a popup dialog
465     * in your implementation of onReceive().
466     *
467     * <p><b>If this BroadcastReceiver was launched through a &lt;receiver&gt; tag,
468     * then the object is no longer alive after returning from this
469     * function.</b>  This means you should not perform any operations that
470     * return a result to you asynchronously -- in particular, for interacting
471     * with services, you should use
472     * {@link Context#startService(Intent)} instead of
473     * {@link Context#bindService(Intent, ServiceConnection, int)}.  If you wish
474     * to interact with a service that is already running, you can use
475     * {@link #peekService}.
476     *
477     * <p>The Intent filters used in {@link android.content.Context#registerReceiver}
478     * and in application manifests are <em>not</em> guaranteed to be exclusive. They
479     * are hints to the operating system about how to find suitable recipients. It is
480     * possible for senders to force delivery to specific recipients, bypassing filter
481     * resolution.  For this reason, {@link #onReceive(Context, Intent) onReceive()}
482     * implementations should respond only to known actions, ignoring any unexpected
483     * Intents that they may receive.
484     *
485     * @param context The Context in which the receiver is running.
486     * @param intent The Intent being received.
487     */
488    public abstract void onReceive(Context context, Intent intent);
489
490    /**
491     * This can be called by an application in {@link #onReceive} to allow
492     * it to keep the broadcast active after returning from that function.
493     * This does <em>not</em> change the expectation of being relatively
494     * responsive to the broadcast (finishing it within 10s), but does allow
495     * the implementation to move work related to it over to another thread
496     * to avoid glitching the main UI thread due to disk IO.
497     *
498     * @return Returns a {@link PendingResult} representing the result of
499     * the active broadcast.  The BroadcastRecord itself is no longer active;
500     * all data and other interaction must go through {@link PendingResult}
501     * APIs.  The {@link PendingResult#finish PendingResult.finish()} method
502     * must be called once processing of the broadcast is done.
503     */
504    public final PendingResult goAsync() {
505        PendingResult res = mPendingResult;
506        mPendingResult = null;
507        return res;
508    }
509
510    /**
511     * Provide a binder to an already-running service.  This method is synchronous
512     * and will not start the target service if it is not present, so it is safe
513     * to call from {@link #onReceive}.
514     *
515     * @param myContext The Context that had been passed to {@link #onReceive(Context, Intent)}
516     * @param service The Intent indicating the service you wish to use.  See {@link
517     * Context#startService(Intent)} for more information.
518     */
519    public IBinder peekService(Context myContext, Intent service) {
520        IActivityManager am = ActivityManagerNative.getDefault();
521        IBinder binder = null;
522        try {
523            service.prepareToLeaveProcess();
524            binder = am.peekService(service, service.resolveTypeIfNeeded(
525                    myContext.getContentResolver()));
526        } catch (RemoteException e) {
527        }
528        return binder;
529    }
530
531    /**
532     * Change the current result code of this broadcast; only works with
533     * broadcasts sent through
534     * {@link Context#sendOrderedBroadcast(Intent, String)
535     * Context.sendOrderedBroadcast}.  Often uses the
536     * Activity {@link android.app.Activity#RESULT_CANCELED} and
537     * {@link android.app.Activity#RESULT_OK} constants, though the
538     * actual meaning of this value is ultimately up to the broadcaster.
539     *
540     * <p class="note">This method does not work with non-ordered broadcasts such
541     * as those sent with {@link Context#sendBroadcast(Intent)
542     * Context.sendBroadcast}</p>
543     *
544     * @param code The new result code.
545     *
546     * @see #setResult(int, String, Bundle)
547     */
548    public final void setResultCode(int code) {
549        checkSynchronousHint();
550        mPendingResult.mResultCode = code;
551    }
552
553    /**
554     * Retrieve the current result code, as set by the previous receiver.
555     *
556     * @return int The current result code.
557     */
558    public final int getResultCode() {
559        return mPendingResult != null ? mPendingResult.mResultCode : 0;
560    }
561
562    /**
563     * Change the current result data of this broadcast; only works with
564     * broadcasts sent through
565     * {@link Context#sendOrderedBroadcast(Intent, String)
566     * Context.sendOrderedBroadcast}.  This is an arbitrary
567     * string whose interpretation is up to the broadcaster.
568     *
569     * <p><strong>This method does not work with non-ordered broadcasts such
570     * as those sent with {@link Context#sendBroadcast(Intent)
571     * Context.sendBroadcast}</strong></p>
572     *
573     * @param data The new result data; may be null.
574     *
575     * @see #setResult(int, String, Bundle)
576     */
577    public final void setResultData(String data) {
578        checkSynchronousHint();
579        mPendingResult.mResultData = data;
580    }
581
582    /**
583     * Retrieve the current result data, as set by the previous receiver.
584     * Often this is null.
585     *
586     * @return String The current result data; may be null.
587     */
588    public final String getResultData() {
589        return mPendingResult != null ? mPendingResult.mResultData : null;
590    }
591
592    /**
593     * Change the current result extras of this broadcast; only works with
594     * broadcasts sent through
595     * {@link Context#sendOrderedBroadcast(Intent, String)
596     * Context.sendOrderedBroadcast}.  This is a Bundle
597     * holding arbitrary data, whose interpretation is up to the
598     * broadcaster.  Can be set to null.  Calling this method completely
599     * replaces the current map (if any).
600     *
601     * <p><strong>This method does not work with non-ordered broadcasts such
602     * as those sent with {@link Context#sendBroadcast(Intent)
603     * Context.sendBroadcast}</strong></p>
604     *
605     * @param extras The new extra data map; may be null.
606     *
607     * @see #setResult(int, String, Bundle)
608     */
609    public final void setResultExtras(Bundle extras) {
610        checkSynchronousHint();
611        mPendingResult.mResultExtras = extras;
612    }
613
614    /**
615     * Retrieve the current result extra data, as set by the previous receiver.
616     * Any changes you make to the returned Map will be propagated to the next
617     * receiver.
618     *
619     * @param makeMap If true then a new empty Map will be made for you if the
620     *                current Map is null; if false you should be prepared to
621     *                receive a null Map.
622     *
623     * @return Map The current extras map.
624     */
625    public final Bundle getResultExtras(boolean makeMap) {
626        if (mPendingResult == null) {
627            return null;
628        }
629        Bundle e = mPendingResult.mResultExtras;
630        if (!makeMap) return e;
631        if (e == null) mPendingResult.mResultExtras = e = new Bundle();
632        return e;
633    }
634
635    /**
636     * Change all of the result data returned from this broadcasts; only works
637     * with broadcasts sent through
638     * {@link Context#sendOrderedBroadcast(Intent, String)
639     * Context.sendOrderedBroadcast}.  All current result data is replaced
640     * by the value given to this method.
641     *
642     * <p><strong>This method does not work with non-ordered broadcasts such
643     * as those sent with {@link Context#sendBroadcast(Intent)
644     * Context.sendBroadcast}</strong></p>
645     *
646     * @param code The new result code.  Often uses the
647     * Activity {@link android.app.Activity#RESULT_CANCELED} and
648     * {@link android.app.Activity#RESULT_OK} constants, though the
649     * actual meaning of this value is ultimately up to the broadcaster.
650     * @param data The new result data.  This is an arbitrary
651     * string whose interpretation is up to the broadcaster; may be null.
652     * @param extras The new extra data map.  This is a Bundle
653     * holding arbitrary data, whose interpretation is up to the
654     * broadcaster.  Can be set to null.  This completely
655     * replaces the current map (if any).
656     */
657    public final void setResult(int code, String data, Bundle extras) {
658        checkSynchronousHint();
659        mPendingResult.mResultCode = code;
660        mPendingResult.mResultData = data;
661        mPendingResult.mResultExtras = extras;
662    }
663
664    /**
665     * Returns the flag indicating whether or not this receiver should
666     * abort the current broadcast.
667     *
668     * @return True if the broadcast should be aborted.
669     */
670    public final boolean getAbortBroadcast() {
671        return mPendingResult != null ? mPendingResult.mAbortBroadcast : false;
672    }
673
674    /**
675     * Sets the flag indicating that this receiver should abort the
676     * current broadcast; only works with broadcasts sent through
677     * {@link Context#sendOrderedBroadcast(Intent, String)
678     * Context.sendOrderedBroadcast}.  This will prevent
679     * any other broadcast receivers from receiving the broadcast. It will still
680     * call {@link #onReceive} of the BroadcastReceiver that the caller of
681     * {@link Context#sendOrderedBroadcast(Intent, String)
682     * Context.sendOrderedBroadcast} passed in.
683     *
684     * <p><strong>This method does not work with non-ordered broadcasts such
685     * as those sent with {@link Context#sendBroadcast(Intent)
686     * Context.sendBroadcast}</strong></p>
687     */
688    public final void abortBroadcast() {
689        checkSynchronousHint();
690        mPendingResult.mAbortBroadcast = true;
691    }
692
693    /**
694     * Clears the flag indicating that this receiver should abort the current
695     * broadcast.
696     */
697    public final void clearAbortBroadcast() {
698        if (mPendingResult != null) {
699            mPendingResult.mAbortBroadcast = false;
700        }
701    }
702
703    /**
704     * Returns true if the receiver is currently processing an ordered
705     * broadcast.
706     */
707    public final boolean isOrderedBroadcast() {
708        return mPendingResult != null ? mPendingResult.mOrderedHint : false;
709    }
710
711    /**
712     * Returns true if the receiver is currently processing the initial
713     * value of a sticky broadcast -- that is, the value that was last
714     * broadcast and is currently held in the sticky cache, so this is
715     * not directly the result of a broadcast right now.
716     */
717    public final boolean isInitialStickyBroadcast() {
718        return mPendingResult != null ? mPendingResult.mInitialStickyHint : false;
719    }
720
721    /**
722     * For internal use, sets the hint about whether this BroadcastReceiver is
723     * running in ordered mode.
724     */
725    public final void setOrderedHint(boolean isOrdered) {
726        // Accidentally left in the SDK.
727    }
728
729    /**
730     * For internal use to set the result data that is active. @hide
731     */
732    public final void setPendingResult(PendingResult result) {
733        mPendingResult = result;
734    }
735
736    /**
737     * For internal use to set the result data that is active. @hide
738     */
739    public final PendingResult getPendingResult() {
740        return mPendingResult;
741    }
742
743    /** @hide */
744    public int getSendingUserId() {
745        return mPendingResult.mSendingUser;
746    }
747
748    /**
749     * Control inclusion of debugging help for mismatched
750     * calls to {@link Context#registerReceiver(BroadcastReceiver, IntentFilter)
751     * Context.registerReceiver()}.
752     * If called with true, before given to registerReceiver(), then the
753     * callstack of the following {@link Context#unregisterReceiver(BroadcastReceiver)
754     * Context.unregisterReceiver()} call is retained, to be printed if a later
755     * incorrect unregister call is made.  Note that doing this requires retaining
756     * information about the BroadcastReceiver for the lifetime of the app,
757     * resulting in a leak -- this should only be used for debugging.
758     */
759    public final void setDebugUnregister(boolean debug) {
760        mDebugUnregister = debug;
761    }
762
763    /**
764     * Return the last value given to {@link #setDebugUnregister}.
765     */
766    public final boolean getDebugUnregister() {
767        return mDebugUnregister;
768    }
769
770    void checkSynchronousHint() {
771        if (mPendingResult == null) {
772            throw new IllegalStateException("Call while result is not pending");
773        }
774
775        // Note that we don't assert when receiving the initial sticky value,
776        // since that may have come from an ordered broadcast.  We'll catch
777        // them later when the real broadcast happens again.
778        if (mPendingResult.mOrderedHint || mPendingResult.mInitialStickyHint) {
779            return;
780        }
781        RuntimeException e = new RuntimeException(
782                "BroadcastReceiver trying to return result during a non-ordered broadcast");
783        e.fillInStackTrace();
784        Log.e("BroadcastReceiver", e.getMessage(), e);
785    }
786}
787
788