registerReceiver 动态注册与 sendBroadcast 源码解析

    广播的注册分为动态注册和静态注册,静态注册主要在开机后PackageManagerService 利用 AndroidManifest 扫描 安装的apk 获取AndroidManifest内注册的 广播 所以 忽略 静态注册。今天主要介绍 动态广播的注册。

   

 1.  简单举例 

  IntentFilter filter = new IntentFilter();

  filter.addAction("android.my.action");

  registerReceiver(broadcastReceiver, filter);//注册监听

     一般注册的代码如上。

   2. 调用 ContextImpl 的 registerReceiver

 @Override
    public Intent registerReceiver(
        BroadcastReceiver receiver, IntentFilter filter) {
        return mBase.registerReceiver(receiver, filter);
    }

    3. 

  1.       最后调用到 registerReceiverInternal ,并将 BroadcastReceiver 封装成 IIntentReceiver 
  2.       IIntentReceiver 继承 IIntentReceiver.Stub 方便 跨进程条用 
  3.       调用 ActivityManagerService 的 registerReceiver 方法  注册 

    @Override
    public Intent registerReceiver(BroadcastReceiver receiver, IntentFilter filter) {
        return registerReceiver(receiver, filter, null, null);
    }
 

@Override
    public Intent registerReceiver(BroadcastReceiver receiver, IntentFilter filter,
            String broadcastPermission, Handler scheduler) {
        return registerReceiverInternal(receiver, getUserId(),
                filter, broadcastPermission, scheduler, getOuterContext());
    }

    @Override
    public Intent registerReceiverAsUser(BroadcastReceiver receiver, UserHandle user,
            IntentFilter filter, String broadcastPermission, Handler scheduler) {
        return registerReceiverInternal(receiver, user.getIdentifier(),
                filter, broadcastPermission, scheduler, getOuterContext());
    }

    private Intent registerReceiverInternal(BroadcastReceiver receiver, int userId,
            IntentFilter filter, String broadcastPermission,
            Handler scheduler, Context context) {
        IIntentReceiver rd = null;
        if (receiver != null) {
            if (mPackageInfo != null && context != null) {
                if (scheduler == null) {
                    scheduler = mMainThread.getHandler();
                }
                rd = mPackageInfo.getReceiverDispatcher(
                    receiver, context, scheduler,
                    mMainThread.getInstrumentation(), true);
            } else {
                if (scheduler == null) {
                    scheduler = mMainThread.getHandler();
                }
                rd = new LoadedApk.ReceiverDispatcher(
                        receiver, context, scheduler, null, true).getIIntentReceiver();
            }
        }
        try {
            return ActivityManagerNative.getDefault().registerReceiver(
                    mMainThread.getApplicationThread(), mBasePackageName,
                    rd, filter, broadcastPermission, userId);
        } catch (RemoteException e) {
            return null;
        }
    }

4 .registerReceiver 方法 集成了 主要的注册函数

  1. 获取 符合 过滤器条件的 粘性广播
  2. mRegisteredReceivers  用 IIntentReceiver asBind 做key  ReceiverList 做 value 。ReceiverList  内 存储 一个BroadcastReceiver 的 所有  过滤信息 。BroadcastReceiver 记录所有广播的所有过滤信息。
     
  3. 如果找到了符合条件的广播则发射广播
  public Intent registerReceiver(IApplicationThread caller, String callerPackage,
            IIntentReceiver receiver, IntentFilter filter, String permission, int userId) {
            。。。。。
            List allSticky = null;

            // Look for any matching sticky broadcasts...
            //获取符合 过滤 器 的 粘性广播  
            Iterator actions = filter.actionsIterator();
            if (actions != null) {
                while (actions.hasNext()) {
                    String action = (String)actions.next();
                    allSticky = getStickiesLocked(action, filter, allSticky,
                            UserHandle.USER_ALL);
                    allSticky = getStickiesLocked(action, filter, allSticky,
                            UserHandle.getUserId(callingUid));
                }
            } else {
                allSticky = getStickiesLocked(null, filter, allSticky,
                        UserHandle.USER_ALL);
                allSticky = getStickiesLocked(null, filter, allSticky,
                        UserHandle.getUserId(callingUid));
            }

            // The first sticky in the list is returned directly back to
            // the client.
                //返回第一个粘性的广播
            Intent sticky = allSticky != null ? (Intent)allSticky.get(0) : null;

            if (DEBUG_BROADCAST) Slog.v(TAG, "Register receiver " + filter
                    + ": " + sticky);

            if (receiver == null) {
                return sticky;
            }
             // ReceiverList 继承 ArrayList 的集合 
            ReceiverList rl
                = (ReceiverList)mRegisteredReceivers.get(receiver.asBinder());
            if (rl == null) {
                rl = new ReceiverList(this, callerApp, callingPid, callingUid,
                        userId, receiver);
                if (rl.app != null) {
                    rl.app.receivers.add(rl);
                } else {
                    try {
                        receiver.asBinder().linkToDeath(rl, 0);
                    } catch (RemoteException e) {
                        return sticky;
                    }
                    rl.linkedToDeath = true;
                }
                  //记录广播
                mRegisteredReceivers.put(receiver.asBinder(), rl);
            } else if (rl.uid != callingUid) {
                throw new IllegalArgumentException(
                        "Receiver requested to register for uid " + callingUid
                        + " was previously registered for uid " + rl.uid);
            } else if (rl.pid != callingPid) {
                throw new IllegalArgumentException(
                        "Receiver requested to register for pid " + callingPid
                        + " was previously registered for pid " + rl.pid);
            } else if (rl.userId != userId) {
                throw new IllegalArgumentException(
                        "Receiver requested to register for user " + userId
                        + " was previously registered for user " + rl.userId);
            }
            BroadcastFilter bf = new BroadcastFilter(filter, rl, callerPackage,
                    permission, callingUid, userId);
              //记录下注册广播的所有过滤器
            rl.add(bf);
            if (!bf.debugCheck()) {
                Slog.w(TAG, "==> For Dynamic broadast");
            }
              //记录下BroadcastFilter  在后期会从BroadcastFilter里面  找寻符合条件的 广播接收者 
            mReceiverResolver.addFilter(bf);

            // Enqueue broadcasts for all existing stickies that match
            // this filter.
            //如果有符合条件的 粘性广播  那么就发送
            if (allSticky != null) {
                ArrayList receivers = new ArrayList();
                receivers.add(bf);

                int N = allSticky.size();
                for (int i=0; i<N; i++) {
                    Intent intent = (Intent)allSticky.get(i);
                    BroadcastQueue queue = broadcastQueueForIntent(intent);
                    BroadcastRecord r = new BroadcastRecord(queue, intent, null,
                            null, -1, -1, null, null, AppOpsManager.OP_NONE, receivers, null, 0,
                            null, null, false, true, true, -1);
                      // 添加记录
                    queue.enqueueParallelBroadcastLocked(r);
                    //执行 发送广播 
                    queue.scheduleBroadcastsLocked();
                }
            }

            return sticky;
        }
    }

5. sendBroadcast 解析

 广播 的发送分为 无序广播,有序广播 ,粘性广播 。 有序广播 就是 按照 等级 顺序 接收 广播 。粘性广播 就是  在第一次发送 广播之后 注册 新的广播 成功能够接收之前的广播。取 无序广播 来解析。

发送 无序广播例子 如下

  Intent intent = new Intent();
  intent.setAction("android.my.action");
  sendBroadcast(intent);

6. sendBroadcast 调用 ContextImple 的 sendBroadcast 发送

   @Override
    public void sendBroadcast(Intent intent) {
        mBase.sendBroadcast(intent);
    }

7. sendBroadcast 在 远程条用 ActivityManagerService 的 broadcastIntent 发送 

  @Override
    public void sendBroadcast(Intent intent) {
        warnIfCallingFromSystemProcess();
        String resolvedType = intent.resolveTypeIfNeeded(getContentResolver());
        try {
            intent.prepareToLeaveProcess();
            ActivityManagerNative.getDefault().broadcastIntent(
                mMainThread.getApplicationThread(), intent, resolvedType, null,
                Activity.RESULT_OK, null, null, null, AppOpsManager.OP_NONE, false, false,
                getUserId());
        } catch (RemoteException e) {
        }
    }

8.

  public final int broadcastIntent(IApplicationThread caller,
            Intent intent, String resolvedType, IIntentReceiver resultTo,
            int resultCode, String resultData, Bundle map,
            String requiredPermission, int appOp, boolean serialized, boolean sticky, int userId) {
        enforceNotIsolatedCaller("broadcastIntent");
        synchronized(this) {
               //校验Intent 
            intent = verifyBroadcastLocked(intent);
          
            final ProcessRecord callerApp = getRecordForAppLocked(caller);
            final int callingPid = Binder.getCallingPid();
            final int callingUid = Binder.getCallingUid();
            final long origId = Binder.clearCallingIdentity();
            int res = broadcastIntentLocked(callerApp,
                    callerApp != null ? callerApp.info.packageName : null,
                    intent, resolvedType, resultTo,
                    resultCode, resultData, map, requiredPermission, appOp, serialized, sticky,
                    callingPid, callingUid, userId);
            Binder.restoreCallingIdentity(origId);
            return res;
        }
    }

9.  broadcastIntentLocked  主要的功能 就是 找到符合 条件的 BroadcastReceiver

  1.  检查 发送的广播是否是粘性广播 如果是的话 记录下来

  2.  PackageManagerService 获取 静态注册 符合 条件 的 Broadcas Reciver,从 mReceiverResolver 获取 符合条件的 动态注册的 Broadcas Reciver

  3. 如果不是有序的 则直接 创建 任务BroadcastRecord加入到BroadcastQueue中   queue.enqueueParallelBroadcastLocked(r);并要求 queue 执行 任务 queue.scheduleBroadcastsLocked();


    private final int broadcastIntentLocked(ProcessRecord callerApp,
            String callerPackage, Intent intent, String resolvedType,
            IIntentReceiver resultTo, int resultCode, String resultData,
            Bundle map, String requiredPermission, int appOp,
            boolean ordered, boolean sticky, int callingPid, int callingUid,
            int userId) {

。。。。。。
        // Add to the sticky list if requested.
        // 如果发送的 是粘性 广播
        if (sticky) {
        	// 检查是否有权限
            if (checkPermission(android.Manifest.permission.BROADCAST_STICKY,
                    callingPid, callingUid)
                    != PackageManager.PERMISSION_GRANTED) {
                String msg = "Permission Denial: broadcastIntent() requesting a sticky broadcast from pid="
                        + callingPid + ", uid=" + callingUid
                        + " requires " + android.Manifest.permission.BROADCAST_STICKY;
                Slog.w(TAG, msg);
                throw new SecurityException(msg);
            }
             //粘性广播不能 要求权限
            if (requiredPermission != null) {
                Slog.w(TAG, "Can't broadcast sticky intent " + intent
                        + " and enforce permission " + requiredPermission);
                return ActivityManager.BROADCAST_STICKY_CANT_HAVE_PERMISSION;
            }
            //粘性 广播不能 显示 指定目标
            if (intent.getComponent() != null) {
                throw new SecurityException(
                        "Sticky broadcasts can't target a specific component");
            }
            // We use userId directly here, since the "all" target is maintained
            // as a separate set of sticky broadcasts.
             	//目标不是 所用用户
            if (userId != UserHandle.USER_ALL) {
                // But first, if this is not a broadcast to all users, then
                // make sure it doesn't conflict with an existing broadcast to
                // all users.
                ArrayMap<String, ArrayList<Intent>> stickies = mStickyBroadcasts.get(
                        UserHandle.USER_ALL);
                if (stickies != null) {
                    ArrayList<Intent> list = stickies.get(intent.getAction());
                    if (list != null) {
                        int N = list.size();
                        int i;
                        for (i=0; i<N; i++) {
                        	//和 以前 的广播一致 则抛异常
                            if (intent.filterEquals(list.get(i))) {
                                throw new IllegalArgumentException(
                                        "Sticky broadcast " + intent + " for user "
                                        + userId + " conflicts with existing global broadcast");
                            }
                        }
                    }
                }
            }
             // 根据 userId分组 粘性广播
            ArrayMap<String, ArrayList<Intent>> stickies = mStickyBroadcasts.get(userId);
            if (stickies == null) {
                stickies = new ArrayMap<String, ArrayList<Intent>>();
                mStickyBroadcasts.put(userId, stickies);
            }
            	// 根据 action 分组  粘性广播
            ArrayList<Intent> list = stickies.get(intent.getAction());
            if (list == null) {
                list = new ArrayList<Intent>();
                stickies.put(intent.getAction(), list);
            }
            int N = list.size();
            int i;
             //和集合内以前 的 Intent 进行比较  条件十分一致 ,一致的话进行替换
            for (i=0; i<N; i++) {
                if (intent.filterEquals(list.get(i))) {
                    // This sticky already exists, replace it.
                    list.set(i, new Intent(intent));
                    break;
                }
            }
            //添加到尾部
            if (i >= N) {
                list.add(new Intent(intent));
            }
        }

        int[] users;
        // 给所有 开始的用户
        if (userId == UserHandle.USER_ALL) {
            // Caller wants broadcast to go to all started users.
            users = mStartedUserArray;
        } else {
            // Caller wants broadcast to go to one specific user.
            users = new int[] {userId};
        }

        // Figure out who all will receive this broadcast.
        List receivers = null;
        List<BroadcastFilter> registeredReceivers = null;
        // Need to resolve the intent to interested receivers...
           //Intent.FLAG_RECEIVER_REGISTERED_ONL 不能发送到Manifest文件注册的广播
        if ((intent.getFlags()&Intent.FLAG_RECEIVER_REGISTERED_ONLY)
                 == 0) {
        	//获取符合条件的在Manifest文件注册的广播
            receivers = collectReceiverComponents(intent, resolvedType, callingUid, users);
        }
        if (intent.getComponent() == null) {
            if (userId == UserHandle.USER_ALL && callingUid == Process.SHELL_UID) {
                // Query one target user at a time, excluding shell-restricted users
                UserManagerService ums = getUserManagerLocked();
                for (int i = 0; i < users.length; i++) {
                    if (ums.hasUserRestriction(
                            UserManager.DISALLOW_DEBUGGING_FEATURES, users[i])) {
                        continue;
                    }
                    //获取符合条件的 动态注册的广播
                    List<BroadcastFilter> registeredReceiversForUser =
                            mReceiverResolver.queryIntent(intent,
                                    resolvedType, false, users[i]);
                    if (registeredReceivers == null) {
                        registeredReceivers = registeredReceiversForUser;
                    } else if (registeredReceiversForUser != null) {
                        registeredReceivers.addAll(registeredReceiversForUser);
                    }
                }
            } else {
                registeredReceivers = mReceiverResolver.queryIntent(intent,
                        resolvedType, false, userId);
            }
        }

        final boolean replacePending =
                (intent.getFlags()&Intent.FLAG_RECEIVER_REPLACE_PENDING) != 0;
        
        if (DEBUG_BROADCAST) Slog.v(TAG, "Enqueing broadcast: " + intent.getAction()
                + " replacePending=" + replacePending);
          //符合要求的代码注册的广播接收者数量
        int NR = registeredReceivers != null ? registeredReceivers.size() : 0;
         //如果 不是有序广播 并且 找到了 符合条件动态注册的 广播接收者
        if (!ordered && NR > 0) {
        	//如果不是有序的广播的话,先执行代码注册的广播接收者
            // If we are not serializing this broadcast, then send the
            // registered receivers separately so they don't wait for the
            // components to be launched.
            final BroadcastQueue queue = broadcastQueueForIntent(intent);
            BroadcastRecord r = new BroadcastRecord(queue, intent, callerApp,
                    callerPackage, callingPid, callingUid, resolvedType, requiredPermission,
                    appOp, registeredReceivers, resultTo, resultCode, resultData, map,
                    ordered, sticky, false, userId);
            if (DEBUG_BROADCAST) Slog.v(
                    TAG, "Enqueueing parallel broadcast " + r);
            final boolean replaced = replacePending && queue.replaceParallelBroadcastLocked(r);
            if (!replaced) {
                queue.enqueueParallelBroadcastLocked(r);
                queue.scheduleBroadcastsLocked();
            }
            registeredReceivers = null;
            NR = 0;
        }

        // Merge into one list.
        int ir = 0;
        if (receivers != null) {
            // A special case for PACKAGE_ADDED: do not allow the package
            // being added to see this broadcast.  This prevents them from
            // using this as a back door to get run as soon as they are
            // installed.  Maybe in the future we want to have a special install
            // broadcast or such for apps, but we'd like to deliberately make
            // this decision.
            String skipPackages[] = null;
            if (Intent.ACTION_PACKAGE_ADDED.equals(intent.getAction())
                    || Intent.ACTION_PACKAGE_RESTARTED.equals(intent.getAction())
                    || Intent.ACTION_PACKAGE_DATA_CLEARED.equals(intent.getAction())) {
                Uri data = intent.getData();
                if (data != null) {
                    String pkgName = data.getSchemeSpecificPart();
                    if (pkgName != null) {
                        skipPackages = new String[] { pkgName };
                    }
                }
            } else if (Intent.ACTION_EXTERNAL_APPLICATIONS_AVAILABLE.equals(intent.getAction())) {
                skipPackages = intent.getStringArrayExtra(Intent.EXTRA_CHANGED_PACKAGE_LIST);
            }
            if (skipPackages != null && (skipPackages.length > 0)) {
                for (String skipPackage : skipPackages) {
                    if (skipPackage != null) {
                        int NT = receivers.size();
                        for (int it=0; it<NT; it++) {
                            ResolveInfo curt = (ResolveInfo)receivers.get(it);
                            if (curt.activityInfo.packageName.equals(skipPackage)) {
                                receivers.remove(it);
                                it--;
                                NT--;
                            }
                        }
                    }
                }
            }

            int NT = receivers != null ? receivers.size() : 0;
            int it = 0;
            ResolveInfo curt = null;
            BroadcastFilter curr = null;
            //排序
            while (it < NT && ir < NR) {
                if (curt == null) {
                    curt = (ResolveInfo)receivers.get(it);
                }
                if (curr == null) {
                    curr = registeredReceivers.get(ir);
                }
                if (curr.getPriority() >= curt.priority) {
                    // Insert this broadcast record into the final list.
                    receivers.add(it, curr);
                    ir++;
                    curr = null;
                    it++;
                    NT++;
                } else {
                    // Skip to the next ResolveInfo in the final list.
                    it++;
                    curt = null;
                }
            }
        }
          //剩余的放后面      
        while (ir < NR) {
            if (receivers == null) {
                receivers = new ArrayList();
            }
            receivers.add(registeredReceivers.get(ir));
            ir++;
        }

        if ((receivers != null && receivers.size() > 0)
                || resultTo != null) {
            BroadcastQueue queue = broadcastQueueForIntent(intent);
            BroadcastRecord r = new BroadcastRecord(queue, intent, callerApp,
                    callerPackage, callingPid, callingUid, resolvedType,
                    requiredPermission, appOp, receivers, resultTo, resultCode,
                    resultData, map, ordered, sticky, false, userId);
            if (DEBUG_BROADCAST) Slog.v(
                    TAG, "Enqueueing ordered broadcast " + r
                    + ": prev had " + queue.mOrderedBroadcasts.size());
            if (DEBUG_BROADCAST) {
                int seq = r.intent.getIntExtra("seq", -1);
                Slog.i(TAG, "Enqueueing broadcast " + r.intent.getAction() + " seq=" + seq);
            }
            boolean replaced = replacePending && queue.replaceOrderedBroadcastLocked(r); 
            if (!replaced) {
                queue.enqueueOrderedBroadcastLocked(r);
                queue.scheduleBroadcastsLocked();
            }
        }

        return ActivityManager.BROADCAST_SUCCESS;
       
         } 

10  BroadcastQueue.scheduleBroadcastsLocked

 只是简单 的sendMessage

 public void scheduleBroadcastsLocked() {
        if (DEBUG_BROADCAST) Slog.v(TAG, "Schedule broadcasts ["
                + mQueueName + "]: current="
                + mBroadcastsScheduled);

        if (mBroadcastsScheduled) {
            return;
        }
        mHandler.sendMessage(mHandler.obtainMessage(BROADCAST_INTENT_MSG, this));
        mBroadcastsScheduled = true;
    }

11.  执行 广播 接收 processNextBroadcast

  @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case BROADCAST_INTENT_MSG: {
                    if (DEBUG_BROADCAST) Slog.v(
                            TAG, "Received BROADCAST_INTENT_MSG");
                    processNextBroadcast(true);
                } break;
                case BROADCAST_TIMEOUT_MSG: {
                    synchronized (mService) {
                        broadcastTimeoutLocked(true);
                    }
                } break;
            }
        }

12 . processNextBroadcast

 简略 介绍  无序广播 的发送 

1. 遍历 任务队列  编列 里面 的BroadCastFilter

2. deliverToRegisteredReceiverLocked  检查 权限是否符合 

final void processNextBroadcast(boolean fromMsg) {


 。。。。。。

  // First, deliver any non-serialized broadcasts right away.
            //执行无序的队列
            while (mParallelBroadcasts.size() > 0) {
                r = mParallelBroadcasts.remove(0);
                r.dispatchTime = SystemClock.uptimeMillis();
                r.dispatchClockTime = System.currentTimeMillis();
                final int N = r.receivers.size();
                if (DEBUG_BROADCAST_LIGHT) Slog.v(TAG, "Processing parallel broadcast ["
                        + mQueueName + "] " + r);
                for (int i=0; i<N; i++) {
                    Object target = r.receivers.get(i);
                    if (DEBUG_BROADCAST)  Slog.v(TAG,
                            "Delivering non-ordered on [" + mQueueName + "] to registered "
                            + target + ": " + r);
                    deliverToRegisteredReceiverLocked(r, (BroadcastFilter)target, false);
                }
                addBroadcastToHistoryLocked(r);
                if (DEBUG_BROADCAST_LIGHT) Slog.v(TAG, "Done with parallel broadcast ["
                        + mQueueName + "] " + r);
            }

。。。。。。


}

13. deliverToRegisteredReceiverLocked 

1. 检查权限 是否符合 

2. 不符合直接跳过 ,符合  调用 performReceiveLocked 

  private final void deliverToRegisteredReceiverLocked(BroadcastRecord r,
            BroadcastFilter filter, boolean ordered) {
        boolean skip = false;
       。。。。。
//这段代码是检查权限的 就不介绍了

        if (!skip) {
            // If this is not being sent as an ordered broadcast, then we
            // don't want to touch the fields that keep track of the current
            // state of ordered broadcasts.
            if (ordered) {
                r.receiver = filter.receiverList.receiver.asBinder();
                r.curFilter = filter;
                filter.receiverList.curBroadcast = r;
                r.state = BroadcastRecord.CALL_IN_RECEIVE;
                if (filter.receiverList.app != null) {
                    // Bump hosting application to no longer be in background
                    // scheduling class.  Note that we can't do that if there
                    // isn't an app...  but we can only be in that case for
                    // things that directly call the IActivityManager API, which
                    // are already core system stuff so don't matter for this.
                    r.curApp = filter.receiverList.app;
                    filter.receiverList.app.curReceiver = r;
                    mService.updateOomAdjLocked(r.curApp);
                }
            }
            try {
                if (DEBUG_BROADCAST_LIGHT) {
                    int seq = r.intent.getIntExtra("seq", -1);
                    Slog.i(TAG, "Delivering to " + filter
                            + " (seq=" + seq + "): " + r);
                }
//远程调用
                performReceiveLocked(filter.receiverList.app, filter.receiverList.receiver,
                    new Intent(r.intent), r.resultCode, r.resultData,
                    r.resultExtras, r.ordered, r.initialSticky, r.userId);
                if (ordered) {
                    r.state = BroadcastRecord.CALL_DONE_RECEIVE;
                }
            } catch (RemoteException e) {
                Slog.w(TAG, "Failure sending broadcast " + r.intent, e);
                if (ordered) {
                    r.receiver = null;
                    r.curFilter = null;
                    filter.receiverList.curBroadcast = null;
                    if (filter.receiverList.app != null) {
                        filter.receiverList.app.curReceiver = null;
                    }
                }
            }
        }
    }

14 performReceiveLocked

利用 Bind 远程调用ApplicationThread 的scheduleRegisteredReceiver 方法 

 private static void performReceiveLocked(ProcessRecord app, IIntentReceiver receiver,
            Intent intent, int resultCode, String data, Bundle extras,
            boolean ordered, boolean sticky, int sendingUser) throws RemoteException {
        // Send the intent to the receiver asynchronously using one-way binder calls.
        if (app != null) {
            if (app.thread != null) {
                // If we have an app thread, do the call through that so it is
                // correctly ordered with other one-way calls.
                app.thread.scheduleRegisteredReceiver(receiver, intent, resultCode,
                        data, extras, ordered, sticky, sendingUser, app.repProcState);
            } else {
                // Application has died. Receiver doesn't exist.
                throw new RemoteException("app.thread must not be null");
            }
        } else {
            receiver.performReceive(intent, resultCode, data, extras, ordered,
                    sticky, sendingUser);
        }
    }

15 . ApplicationThread  .scheduleRegisteredReceiver

 public void scheduleRegisteredReceiver(IIntentReceiver receiver, Intent intent,
                int resultCode, String dataStr, Bundle extras, boolean ordered,
                boolean sticky, int sendingUser, int processState) throws RemoteException {
            updateProcessState(processState, false);
            receiver.performReceive(intent, resultCode, dataStr, extras, ordered,
                    sticky, sendingUser);
        }

16 IIntentReceiver   performReceive 

IIntentReceiver    是在 LoadAp.ReceiverDispatcher.ReceiverDispatcher内的 类 .

 

  1. 生成 Args  对象 ,Args 继承 BroadcastReceiver.PendingResult 实现 Runable 
  2. ActivityThread.post Args 执行 run 方法
  public void performReceive(Intent intent, int resultCode, String data,
                Bundle extras, boolean ordered, boolean sticky, int sendingUser) {
            if (ActivityThread.DEBUG_BROADCAST) {
                int seq = intent.getIntExtra("seq", -1);
                Slog.i(ActivityThread.TAG, "Enqueueing broadcast " + intent.getAction() + " seq=" + seq
                        + " to " + mReceiver);
            }
            Args args = new Args(intent, resultCode, data, extras, ordered,
                    sticky, sendingUser);
            if (!mActivityThread.post(args)) {
                if (mRegistered && ordered) {
                    IActivityManager mgr = ActivityManagerNative.getDefault();
                    if (ActivityThread.DEBUG_BROADCAST) Slog.i(ActivityThread.TAG,
                            "Finishing sync broadcast to " + mReceiver);
                    args.sendFinished(mgr);
                }
            }
        }

17 Args run方法

其核心代码就是 执行 BroadcastReceiver 的 onReceive方法

。。。。。。

 try {
                    ClassLoader cl =  mReceiver.getClass().getClassLoader();
                    intent.setExtrasClassLoader(cl);
                    setExtrasClassLoader(cl);
                    receiver.setPendingResult(this);
                    receiver.onReceive(mContext, intent);
                } catch (Exception e) {
                    if (mRegistered && ordered) {
                        if (ActivityThread.DEBUG_BROADCAST) Slog.i(ActivityThread.TAG,
                                "Finishing failed broadcast to " + mReceiver);
                        sendFinished(mgr);
                    }
                    if (mInstrumentation == null ||
                            !mInstrumentation.onException(mReceiver, e)) {
                        Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
                        throw new RuntimeException(
                            "Error receiving broadcast " + intent
                            + " in " + mReceiver, e);
                    }
                }

。。。。。。

 

    原文作者:qq_21237965
    原文地址: https://blog.csdn.net/qq_21237965/article/details/84104441
    本文转自网络文章,转载此文章仅为分享知识,如有侵权,请联系博主进行删除。
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