SUPL Push API Tutorial

This topic describes how the Symbian SUPL WAP Push plug-in uses the SUPL Push API (deprecated). Device creators can use this information if they want to implement their own SUPL INIT push plug-in.

1. Define a SUPL INIT handler class The Symbian WAP Push plug-in derives from CContentHandlerBase to receive SUPL WAP Push messages. It implements MLbsSuplPushObserver to receive notification of successful message delivery to the SUPL Protocol Module.

   
   NONSHARABLE_CLASS(CLbsSuplWapPush) : public CContentHandlerBase, public MLbsSuplPushObserver
       {
   public:
       static CLbsSuplWapPush* NewL();
       virtual ~CLbsSuplWapPush();
       
       virtual void OnSuplInitComplete(TLbsSuplPushChannel aChannel, TLbsSuplPushRequestId aReqId, 
               TInt aError, TInt aReserved);
   
       // From CPushHandlerBase
       virtual void HandleMessageL(CPushMessage* aPushMsg);
       
       // Other methods of CContentHandlerBase omitted here...
   
   };
   

   The plug-in's ConstructL() creates a new instance of CLbsSuplPush.

   
   // This handler uses the WAP channel
   iSuplPush = CLbsSuplPush::NewL(ELbsSuplPushChannelWAP, *this);
   

2. Implement HandleMessageL() When the WAP Push plug-in receives a WAP Push message, it extracts the message body and calls CLbsSuplPush::SuplInit().

   
   void CLbsSuplWapPush::HandleMessageL(CPushMessage* aPushMsg)
       {
       LBSLOG(ELogP3, "SUPL WAP Push : CLbsSuplWapPush::HandleMessageL");
       if(aPushMsg)
           {
           TPtrC8 body;
           TBool hasBody=aPushMsg->GetMessageBody(body);
           if(hasBody)
               {
               TLbsSuplPushRequestId reqId;
               TInt err=iSuplPush->SuplInit(reqId, body, 0);
               if(KErrNone==err)
                   {
                   LBSLOG2(ELogP3,"SUPL WAP Push : Started to deliver the message, reqId=%d", reqId);
                   delete aPushMsg;
                   return;
                   }
               else
                   {
                   LBSLOG2(ELogP3,"SUPL WAP Push : CLbsSuplPush::SuplInit failed, err=%d", err);
                   }
               }
           else
               {
               LBSLOG(ELogP3, "SUPL WAP Push : Empty message body, the message is skipped");
               }
           delete aPushMsg;
           }
       else
           {
           LBSLOG(ELogP3, "SUPL WAP Push : Null message pointer, the message is skipped");
           }
    iPluginKiller->KillPushPlugin();
       }
   

3. Implement MLbsSuplPushObserver::OnSuplInitComplete() When the SUPL Protocol Module processes the SUPL INIT message, the plug-in's MLbsSuplPushObserver::OnSuplInitComplete() method is called. The parameter aError may indicate a timeout or another error condition. The WAP Push plug-in is destroyed by the WAP Push Framework. Another instance of CLbsSuplWapPush is created by the framework to handle the next SUPL INIT received by WAP Push.

   
   void CLbsSuplWapPush::OnSuplInitComplete(TLbsSuplPushChannel /*aChannel*/, TLbsSuplPushRequestId aReqId, 
               TInt aError, TInt /*aReserved*/)
       {
       if(aError==KErrNone)
           {
           LBSLOG2(ELogP3,"SUPL WAP Push : Message delivered successfully, reqId=%d", aReqId);
           }
       else
           {
           LBSLOG3(ELogP3,"SUPL WAP Push : Message delivery failed, reqId=%d, err=%d", aReqId, aError);
           }
        iPluginKiller->KillPushPlugin();
       }