IM Application Launch API: Using IM Application Launch API

Initially the user is logged in (CSP session exists), and the user application which receives the instant message is running. This user application has registered itself using an ID as specified in IM API. Now if the user application stops running (but the user is logged in to the remote server) and if the server sends an instant message, the ECom plug-in is loaded. This plug-in must start the user application again. This application must implement the APIs mentioned in IM API to receive the messages. Once the application starts, it starts receiving the instant messages. All pending messages are sent to the application. Since the whole process may take some time, the user application can use appropriate mechanism to inform the user.

Receiving an orphaned message when application start is ongoing

An instant message is received and it triggers the application start and the start is ongoing. In case of different Application ID, the request is queued too. In case of the same Application ID, the user application is started and both instant messages are received. In case of a different user ID, both user applications are started and each receives its instant message. After the application is started successfully, all orphaned messages are received by the application. If the Application ID was different from the Application ID, which triggered the ongoing launching, the new launching is initiated starting the application registered with that Application ID.

Launching the application which handles the instant message received by the IM protocol stack

The plug-in for launching the user application implements the ECom interface for launching the user application. Upon the process creation, a string can be passed to the launcher process as a parameter. The string is the actual Application ID of the user application.

In order to launch the application which handles the instant message received by the IM protocol stack, an ECom plug-in needs to be installed which implements the following interface from imlaucherplugin.h include file.

If the application does not use Application ID for registering to the IM protocol stack, then the default_data field should contain the string “Default”. There should be only one application registered with the “Default” keyword as the application launcher tries to start the first implementation found by the ECom framework.

//Example resource file
// 101FB0CD.RSS
#include "RegistryInfo.rh"

// Declares info for two implementations
RESOURCE REGISTRY_INFO theInfo
    {
    // UID for the DLL
    dll_uid = 0x101FB0CD;
    // Declare array of interface info
    interfaces = 
        {
        INTERFACE_INFO
            {
            // UID of interface that is implemented
            interface_uid = 0x101FB0CC;
            implementations = 
                {
                IMPLEMENTATION_INFO
			{
			implementation_uid = 0x101FB0D1;
			version_no = 1;
			display_name = "Test launcher plugin";
			default_data = "Default";
			opaque_data = "";
			}
		};
	    }
	};
  }

The following example code is an implementation of two interfaces StartApplicationL and CancelStartApplication. The first one connects to the server which provides access to a cached list of the applications on the device and starts the application chat.app. The latter one cancels the start of chat.app

// Implementation of StartApplicationL
//aSAP and aUserId can also be used as per the requirement
void CTestPlugin::StartApplicationL(TRequestStatus& aStatus)
    {
    // The application file which is going to be started
    _LIT(KAppName, "z:\\System\\Apps\\Chat\\chat.app");
    iStatus = &aStatus;
    CApaCommandLine* cmdLine=CApaCommandLine::NewLC();
    cmdLine->SetLibraryNameL(KAppName);
    cmdLine->SetCommandL(EApaCommandRun);
    RApaLsSession ls;
    TInt result( ls.Connect() );
    if (result == KErrNone)
       {
       ls.StartApp(*cmdLine);
       }

    CleanupStack::PopAndDestroy(); // commandline

    // Return the result to the service user
    User::RequestComplete(iStatus, result);
    }

            
            
            
            
            
            // Implementation of CancelStartApplication 
void CTestPlugin::CancelStartApplication()
     {
     User::RequestComplete(iStatus, KErrCancel);
     }