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MMS发送流程

 
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1.      点击发送按钮Src/com/android/mms/ui/ComposeMessageActivity.java

public void onClick(View v) {

        if ((v == mSendButton) && isPreparedForSending()) {

            confirmSendMessageIfNeeded(); //确认是否需要发送短信—-》

        }
}

2.src/com/android/mms/ui/ComposeMessageActivity.java

private void confirmSendMessageIfNeeded() {

        if (!isRecipientsEditorVisible()) {  //编辑联系人不可见时,也就是给已存在会话的联系人发送短信时

            sendMessage(true);

            return;

        }

        boolean isMms = mWorkingMessage.requiresMms();   //是否需要以彩信形式发送

                if (mRecipientsEditor.hasInvalidRecipient(isMms)) {//是否含有不合法的收件人

            if (mRecipientsEditor.hasValidRecipient(isMms)) {//有合法的和不合法的,弹出尝试发送对话框

                String title = getResourcesString(R.string.has_invalid_recipient,

                        mRecipientsEditor.formatInvalidNumbers(isMms));

                new AlertDialog.Builder(this)

                   .setIcon(android.R.drawable.ic_dialog_alert)

                    .setTitle(title)

                    .setMessage(R.string.invalid_recipient_message)

                   .setPositiveButton(R.string.try_to_send,

                            newSendIgnoreInvalidRecipientListener())

                   .setNegativeButton(R.string.no, new CancelSendingListener())

                    .show();

            } else {//如果全是不合法的联系人,提示不能发送信息

                new AlertDialog.Builder(this)

                   .setIcon(android.R.drawable.ic_dialog_alert)

                    .setTitle(R.string.cannot_send_message)

                    .setMessage(R.string.cannot_send_message_reason)

                   .setPositiveButton(R.string.yes, new CancelSendingListener())

                    .show();

            }

        } else {//判断收件人没有问题,接着发送信息 --》

            sendMessage(true);

        }
}

3. src/com/android/mms/ui/ComposeMessageActivity.java

private void sendMessage(boolean bCheckEcmMode) {

    Log.v(TAG, "sendMessage");

        if (bCheckEcmMode) {

            // TODO: expose this in telephony layer for SDK build

            String inEcm = SystemProperties.get(TelephonyProperties.PROPERTY_INECM_MODE);     //判断电话是否处于紧急拨号模式,得到的inEcm一般为空

            Log.v(TAG, "inEcm = " + inEcm);

            if (Boolean.parseBoolean(inEcm)) {

                try {

                    startActivityForResult(

                            new Intent(TelephonyIntents.ACTION_SHOW_NOTICE_ECM_BLOCK_OTHERS,null),

                            REQUEST_CODE_ECM_EXIT_DIALOG);

                    return;

                } catch (ActivityNotFoundException e) {

                    // continue to send message

                    Log.e(TAG, "Cannot find EmergencyCallbackModeExitDialog", e);

                }

            }

        }

        if (!mSendingMessage) {

            // send can change the recipients. Make sure we remove the listeners firstand then add

            // them back once the recipient list has settled.

            removeRecipientsListeners();  //取消对收件人的监听

            mWorkingMessage.send();   //发送信息—-》

            mSentMessage = true;

            mSendingMessage = true;

            addRecipientsListeners(); //重新添加收件人监听

        }

        // But bail out if we are supposed to exit after the message is sent.

        if (mExitOnSent) {//如果mExitOnSent为true,信息发送完成后退出Activity

            finish();

        }
    }

4. src/com/android/mms/data/WorkingMessage.java

/**

     * Send this message over the network.  Will call back with onMessageSent() once

     * it has been dispatched to the telephonystack.  This WorkingMessage object is

     * no longer useful after this method hasbeen called.

     */

    public void send() {

        if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

            LogTag.debug("send");

        }

        // Get ready to write to disk.

        prepareForSave(true /* notify */);//主要做一下同步收件人和WorkingMessage,彩信时在准备其他一些东西

        // We need the recipient list for both SMS and MMS.

        final Conversation conv = mConversation;

        String msgTxt = mText.toString();

        Log.v(TAG, "msgText = " + msgTxt);

        if (requiresMms()|| addressContainsEmailToMms(conv, msgTxt)) {

            // Make local copies of the bits we need for sending a message,

            // because we will be doing it off of the main thread, which will

            // immediately continue on to resetting some of this state.

            final Uri mmsUri = mMessageUri;   //如果第一次发送,此时mmsUri为null,如果是重发,则是草稿箱的地址 mMessageUri =content://mms/drafts/1

            final PduPersister persister = PduPersister.getPduPersister(mContext);

            final SlideshowModel slideshow = mSlideshow;

            final SendReq sendReq = makeSendReq(conv,mSubject);

            // Do the dirty work of sending the message off of the main UI thread.

            new Thread(new Runnable() {

                public void run() {

                    // Make sure the text in slide 0 is no longer holding onto a reference to

                    // the text in the message text box.

                    slideshow.prepareForSend();

                    sendMmsWorker(conv, mmsUri, persister, slideshow, sendReq);

                }

            }).start();

        }else {

            // Same rules apply as above.

            final String msgText = mText.toString();//取出短消息

            Log.v(TAG, "msgText = " + msgText);

            new Thread(new Runnable() {

                public void run() {

                    preSendSmsWorker(conv, msgText);//发送信息--》

                }

            }).start();

        }

        // update the Recipient cache with the new to address, if it's different

        RecipientIdCache.updateNumbers(conv.getThreadId(),conv.getRecipients());

        // Mark the message as discarded because it is "off the market"after being sent.

        mDiscarded = true;

    }

5. src/com/android/mms/data/WorkingMessage.java

private void sendMmsWorker(Conversation conv, Uri mmsUri, PduPersisterpersister, SlideshowModel slideshow, SendReq sendReq) {

    Log.v(TAG, "sendMmsWorker");

        // If user tries to send the message, it's a signal the inputtedtext is what they wanted.

        UserHappinessSignals.userAcceptedImeText(mContext);

        // First make sure we don't have too many outstanding unsent message.

        Cursor cursor = null;

        try {

            cursor = SqliteWrapper.query(mContext, mContentResolver,

                    Mms.Outbox.CONTENT_URI,MMS_OUTBOX_PROJECTION, null, null, null);

            if (cursor != null) {//如果MMS_OUTBOX里有未发送的彩信,并且总的大小已经超过了彩信的最大限制,则取消此次发送,并存入草稿箱

              Log.v(TAG, "query Mms.Outbox.CONTENT_URI is not empty");

                long maxMessageSize = MmsConfig.getMaxSizeScaleForPendingMmsAllowed()*

                    MmsConfig.getMaxMessageSize();

                Log.v(TAG, "MmsConfig.getMaxSizeScaleForPendingMmsAllowed() =" + MmsConfig.getMaxSizeScaleForPendingMmsAllowed());

                Log.v(TAG, "MmsConfig.getMaxMessageSize()() = " + MmsConfig.getMaxMessageSize());

              

                long totalPendingSize = 0;

                while (cursor.moveToNext()) {

                    totalPendingSize +=cursor.getLong(MMS_MESSAGE_SIZE_INDEX);

                    Log.v(TAG, "totalPendingSize = " + totalPendingSize);

                }

                if (totalPendingSize >= maxMessageSize) {

                    unDiscard();    // itwasn't successfully sent. Allow it to be saved as a draft.

                    mStatusListener.onMaxPendingMessagesReached();

                    return;

                }

            }else{

              Log.v(TAG, "query Mms.Outbox.CONTENT_URI is empty");

            }

        } finally {

            if (cursor != null) {

                cursor.close();

            }

        }

        mStatusListener.onPreMessageSent();

        // Make sure we are still using the correct thread ID for our

        // recipient set.

        long threadId = conv.ensureThreadId();

        if (Log.isLoggable(LogTag.APP, Log.VERBOSE)) {

            LogTag.debug("sendMmsWorker: update draft MMS message " + mmsUri);

        }

        if (mmsUri == null) {//如果是首次发送,先把彩信保存入草稿箱

            // Create a new MMS message if one hasn't been made yet.

        Log.v(TAG, "mmsUri == null and startcreateDraftMmsMessage");

            mmsUri = createDraftMmsMessage(persister,sendReq, slideshow);

        } else {

            // Otherwise, sync the MMS message in progress to disk.

        Log.v(TAG, "mmsUri = " + mmsUri);

        Log.v(TAG, "updateDraftMmsMessage");

            updateDraftMmsMessage(mmsUri,persister, slideshow, sendReq);

        }

        // Be paranoid and clean any draft SMS up.

        deleteDraftSmsMessage(threadId);

        // Resize all the resizeable attachments (e.g. pictures) to fit

        // in the remaining space in the slideshow.

        int error = 0;

        try {

            slideshow.finalResize(mmsUri);

        } catch (ExceedMessageSizeException e1) {

            error = MESSAGE_SIZE_EXCEEDED;

        } catch (MmsException e1) {

            error = UNKNOWN_ERROR;

        }

        if (error != 0) {

            markMmsMessageWithError(mmsUri);

            mStatusListener.onAttachmentError(error);

            return;

        }

        MessageSender sender = new MmsMessageSender(mContext, mmsUri,

               slideshow.getCurrentMessageSize());

        try {

            if (!sender.sendMessage(threadId)) {

                // The message was sent through SMS protocol, we should

                // delete the copy which was previously saved in MMS drafts.

                SqliteWrapper.delete(mContext, mContentResolver, mmsUri, null, null);

            }

            // Make sure this thread isn't over the limits in message count

            Recycler.getMmsRecycler().deleteOldMessagesByThreadId(mContext, threadId);

        } catch (Exception e) {

            Log.e(TAG, "Failed to send message: " + mmsUri + ",threadId=" + threadId, e);

        }

        mStatusListener.onMessageSent();

}

6.src/com/android/mms/transaction/MmsMessageSender.java

public boolean sendMessage(long token) throws MmsException {

        // Load the MMS from the message uri

        PduPersister p = PduPersister.getPduPersister(mContext);

        GenericPdu pdu = p.load(mMessageUri);

        if (pdu.getMessageType() != PduHeaders.MESSAGE_TYPE_SEND_REQ){

            throw new MmsException("Invalid message: " +pdu.getMessageType());

        }

        SendReq sendReq = (SendReq)pdu;

        // Update headers.

        updatePreferencesHeaders(sendReq);

        // MessageClass.

        sendReq.setMessageClass(DEFAULT_MESSAGE_CLASS.getBytes());

        // Update the 'date' field of the message before sending it.

        sendReq.setDate(System.currentTimeMillis()/ 1000L);

     

        sendReq.setMessageSize(mMessageSize);

        p.updateHeaders(mMessageUri, sendReq);

        // Move the message into MMS Outbox

        p.move(mMessageUri, Mms.Outbox.CONTENT_URI);

        // Start MMS transaction service

        SendingProgressTokenManager.put(ContentUris.parseId(mMessageUri), token);

        mContext.startService(new Intent(mContext, TransactionService.class));

        return true;

    }

7.src/com/android/mms/transaction/TransactionService.java

@Override

    public int onStartCommand(Intent intent, int flags, int startId) {

    Log.v(TAG, "onStartCommand");

        if (intent == null) {

            return Service.START_NOT_STICKY;

        }

        mConnMgr = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);

        boolean noNetwork =!isNetworkAvailable();

        if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

            Log.v(TAG, "onStart: #" + startId + ": " + intent.getExtras() + " intent=" + intent);

            Log.v(TAG, "   networkAvailable=" + !noNetwork);

        }

        Log.v(TAG, "getAction is " + intent.getAction());

        if (ACTION_ONALARM.equals(intent.getAction())|| (intent.getExtras() == null)) {

        Log.v(TAG, "ACTION_ONALARM.equals(intent.getAction()) ||(intent.getExtras() == null)");

            // Scan database to find all pending operations.

            Cursor cursor = PduPersister.getPduPersister(this).getPendingMessages(

                    System.currentTimeMillis());

            if (cursor != null) {

                try {

                    int count = cursor.getCount();

                    if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                        Log.v(TAG, "onStart: cursor.count=" + count);

                    }

                    if (count == 0) {

                        if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                            Log.v(TAG, "onStart: no pending messages. Stoppingservice.");

                        }

                        RetryScheduler.setRetryAlarm(this);

                       stopSelfIfIdle(startId);

                        return Service.START_NOT_STICKY;

                    }

                    int columnIndexOfMsgId =cursor.getColumnIndexOrThrow(PendingMessages.MSG_ID);

                    int columnIndexOfMsgType =cursor.getColumnIndexOrThrow(

                            PendingMessages.MSG_TYPE);

                    if (noNetwork) {

                        // Make sure we register for connection state changes.

                        if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                            Log.v(TAG, "onStart: registerForConnectionStateChanges");

                        }

                        MmsSystemEventReceiver.registerForConnectionStateChanges(

                               getApplicationContext());

                    }

                    while (cursor.moveToNext()) {

                        int msgType =cursor.getInt(columnIndexOfMsgType);

                        int transactionType =getTransactionType(msgType);

                        Log.v(TAG, "msgType = " + msgType);

                        Log.v(TAG, "transactionType = " + transactionType);

                        if (noNetwork) {

                           onNetworkUnavailable(startId, transactionType);

                            return Service.START_NOT_STICKY;

                        }

                      

                        switch (transactionType){

                            case -1:

                                break;

                            case Transaction.RETRIEVE_TRANSACTION:

                                // If it's a transiently failed transaction,

                                // we should retry it in spite of current

                                // downloading mode.

                                int failureType =cursor.getInt(

                                       cursor.getColumnIndexOrThrow(

                                               PendingMessages.ERROR_TYPE));

                                if (!isTransientFailure(failureType)){

                                    break;

                                }

                                // fall-through

                            default:

                                Uri uri =ContentUris.withAppendedId(

                                        Mms.CONTENT_URI,

                                       cursor.getLong(columnIndexOfMsgId));

                               TransactionBundle args = new TransactionBundle(

                                       transactionType, uri.toString());

                                // FIXME: We use the same startId for all MMs.

                                launchTransaction(startId, args, false);

                                break;

                        }

                    }

                } finally {

                    cursor.close();

                }

            } else {

                if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                    Log.v(TAG, "onStart: no pending messages. Stoppingservice.");

                }

                RetryScheduler.setRetryAlarm(this);

                stopSelfIfIdle(startId);

            }

        } else {

            if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                Log.v(TAG, "onStart: launch transaction...");

            }

            // For launching NotificationTransaction and test purpose.

            TransactionBundle args = newTransactionBundle(intent.getExtras());

            launchTransaction(startId, args,noNetwork);

        }

        return Service.START_NOT_STICKY;

    }

8. src/com/android/mms/transaction/TransactionService.java

private void launchTransaction(int serviceId,TransactionBundle txnBundle, boolean noNetwork) {

    Log.v(TAG, "launchTransaction");

        if (noNetwork) {

            Log.w(TAG, "launchTransaction: no network error!");

            onNetworkUnavailable(serviceId,txnBundle.getTransactionType());

            return;

        }

        Message msg = mServiceHandler.obtainMessage(EVENT_TRANSACTION_REQUEST);

        msg.arg1 = serviceId;

        msg.obj = txnBundle;

        if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

            Log.v(TAG, "launchTransaction: sending message " + msg);

        }

        mServiceHandler.sendMessage(msg);

    }

9. src/com/android/mms/transaction/TransactionService.java

private final class ServiceHandler extends Handler {

        public ServiceHandler(Looper looper) {

            super(looper);

        }

        /**

         * Handle incoming transactionrequests.

         * The incoming requests are initiatedby the MMSC Server or by the

         * MMS Client itself.

         */

        @Override

        public void handleMessage(Messagemsg) {

            if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                Log.v(TAG, "Handling incoming message: " + msg);

            }

            Transaction transaction = null;

            switch (msg.what) {

                case EVENT_QUIT:

                    getLooper().quit();

                    return;

                case EVENT_CONTINUE_MMS_CONNECTIVITY:

                    synchronized (mProcessing) {

                        if (mProcessing.isEmpty()) {

                            return;

                        }

                    }

                    if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                        Log.v(TAG, "handle EVENT_CONTINUE_MMS_CONNECTIVITYevent...");

                    }

                    try {

                        int result =beginMmsConnectivity();

                        if (result != Phone.APN_ALREADY_ACTIVE){

                            Log.v(TAG, "Extending MMS connectivity returned " + result +

                                    " instead of APN_ALREADY_ACTIVE");

                            // Just wait for connectivity startup without

                            // any newrequest of APN switch.

                            return;

                        }

                    } catch (IOException e) {

                        Log.w(TAG, "Attempt to extend use of MMS connectivityfailed");

                        return;

                    }

                    // Restart timer

                   sendMessageDelayed(obtainMessage(EVENT_CONTINUE_MMS_CONNECTIVITY),

                                       APN_EXTENSION_WAIT);

                    return;

                case EVENT_DATA_STATE_CHANGED:

                    /*

                     * If we are being informedthat connectivity has been established

                     * to allow MMS traffic,then proceed with processing the pending

                     * transaction, if any.

                     */

                    if (mConnectivityListener == null) {

                        return;

                    }

                    NetworkInfo info = mConnectivityListener.getNetworkInfo();

                    if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                        Log.v(TAG, "Handle DATA_STATE_CHANGED event: " + info);

                    }

                    // Check availability of the mobile network.

                    if ((info == null) || (info.getType() !=

                           ConnectivityManager.TYPE_MOBILE_MMS)) {

                        if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                            Log.v(TAG, "   type isnot TYPE_MOBILE_MMS, bail");

                        }

                        return;

                    }

                    if (!info.isConnected()) {

                        if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                            Log.v(TAG, "  TYPE_MOBILE_MMS not connected, bail");

                        }

                        return;

                    }

                    TransactionSettings settings = newTransactionSettings(

                            TransactionService.this,info.getExtraInfo());

                    // If this APN doesn't have an MMSC, wait for one that does.

                    if (TextUtils.isEmpty(settings.getMmscUrl())){

                        if (Log.isLoggable(LogTag.TRANSACTION, Log.VERBOSE)) {

                            Log.v(TAG, "   empty MMSCurl, bail");

                        }

                        return;

                    }

                    // Set a timer to keep renewing our "lease" on the MMSconnection

                   sendMessageDelayed(obtainMessage(EVENT_CONTINUE_MMS_CONNECTIVITY),

                                       APN_EXTENSION_WAIT);

                   processPendingTransaction(transaction, settings);

                    return;

                case EVENT_TRANSACTION_REQUEST://响应请求

                  Log.v(TAG, "EVENT_TRANSACTION_REQUEST");

                    int serviceId = msg.arg1;

                    try {

                        TransactionBundle args= (TransactionBundle) msg.obj;

                        TransactionSettingstransactionSettings;

                        // Set the connection settings for this transaction.

                        // If these have not been set in args, load thedefault settings.

                        String mmsc =args.getMmscUrl();

                        if (mmsc != null) {

                            transactionSettings= new TransactionSettings(

                                    mmsc,args.getProxyAddress(), args.getProxyPort());

                        } else {

                            transactionSettings= new TransactionSettings(

                                                   TransactionService.this, null);

                        }

                        int transactionType =args.getTransactionType();

                        Log.v(TAG, "transactionType = " + transactionType)
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