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ID	CS000817	Creation date	February 8, 2008, updated April 23, 2009
Platform	S60 3rd Edition, S60 5th Edition	Tested on devices
Category	Symbian C++	Subcategory	Data&Files

Keywords (APIs, classes, methods, functions):

Note!
This API is not part of the public SDK. It can be found in the SDK API Plug-in.

Description

The following code demonstrates how to install and uninstall a MIDlet programmatically using the Software Installer APIs.

Solution

Installing a MIDlet

A MIDlet can be installed using the SW installer APIs as below:

Capability requirements: TrustedUI

   SwiUI::RSWInstSilentLauncher iLauncher; 
   SwiUI::TInstallOptions iOptions;
   SwiUI::TInstallOptionsPckg iOptionsPckg;

   // Connect to software installer server
   User::LeaveIfError(iLauncher.Connect());

   iOptions.iUpgrade = SwiUI::EPolicyNotAllowed;
   iOptions.iOCSP = SwiUI::EPolicyAllowed;
   iOptions.iDrive = 'C';   
   iOptionsPckg = iOptions;

   iLauncher.SilentInstall( iStatus, KPathAndFileNameOfJarFile, iOptionsPckg );
   SetActive();

The above code is meant to be run by an active object (derived from CActive) and uses the asynchronous version of SilentInstall() method.

It is also possible to install a MIDlet using the CDocumentHandler API. For more information on this API, refer to SDK Help.

Uninstalling a MIDlet

Note!
This method is deprecated and no longer works from S60 3rd Edition, Feature Pack 2 onwards.

When a MIDlet suite (possibly containing several MIDlets) is installed, the system creates a Suite UID for it and stores it in the Java registry. However, the only way to uninstall a MIDlet is to uninstall the parent MIDlet Suite. The MIDlet Suite UID must be passed to SwiUI::RSWInstSilentLauncher. However, this UID cannot be retrieved with methods from RApaLsSession.

Every time a MIDlet is installed, a new UID is generated for the application. Installer also creates some files for each installed MIDlet:

 C:\private\102033E6\MIDlets\[UID]\    (directory named with MIDlet Suite UID)

MIDlet .jar and .jad files are copied to this directory. It is possible to extract the MIDlet context (Suite) UID by searching the C:\System\install\registry\ directory for "<UID>.reg" files. If the MIDlet name appears inside the .reg file, it can be assumed that the registry file belongs to the correct MIDlet Suite. This UID can then be passed to SwiUI::RSWInstSilentLauncher in order to uninstall the Suite.

void CJarUninstallAppUi::UninstallMIDletL()
 {
 RFs fileSession;
 CDir* dirList;
 TInt i;
 TFileName fullPath;
 TUint contextUid;
 TFileName fileName;
 
 _LIT(KDirName1, "c:\\system\\install\\registry\\");
 _LIT(KFileSpec1,"c:\\system\\install\\registry\\*.*");
 
 User::LeaveIfError( fileSession.Connect() );
 CleanupClosePushL( fileSession );
 
 // Get the file list, sorted by name
 User::LeaveIfError( fileSession.GetDir( KFileSpec1, 
                                         KEntryAttMaskSupported, 
                                         ESortByName, dirList ) );
 CleanupStack::PushL(dirList);
 
 for ( i=0; i < dirList->Count(); i++ )
   {
   fileName = (*dirList)[i].iName;
   if( fileName.Compare(_L("temp")) == KErrNone )
     {
     continue;	
     }
 
   fullPath = KDirName1;
   fullPath.Append(fileName);
   RFile lFile;
   TInt err = lFile.Open( fileSession, fullPath, EFileShareAny | EFileRead );
   
   if(err == KErrNone)
     {
     TInt lSize;
     lFile.Size(lSize);
     RBuf8 lBuf;
     lBuf.Create(lSize);
     lBuf.CleanupClosePushL();
     lFile.Read(lBuf);//read contents into buffer
     RBuf buff;
     buff.Create(lSize);
     buff.CleanupClosePushL();
     buff.Copy(lBuf);//Copy into 16 bit buffer
     lFile.Close();
     if (err == KErrNone)
       {
       // Check for MIDlet name in the file
       err = buff.Find(_L("somemidlet.jar"));
       if (err != KErrNotFound)
         {
         TLex lex( fileName.Mid(0,8) );
         lex.Val( contextUid, EHex );
         SwiUI::RSWInstSilentLauncher inst; 
         inst.Connect(); 
         SwiUI::TUninstallOptions options; 
         SwiUI::TUninstallOptionsPckg optionsPckg; 
         options.iKillApp = SwiUI::EPolicyAllowed; 
         options.iBreakDependency = SwiUI::EPolicyAllowed; 
         optionsPckg = options; 
         TInt resp = inst.SilentUninstall( TUid::Uid(contextUid), 
                                           optionsPckg, 
                                           SwiUI::KJavaMIMEType ); 
         inst.Close(); 
         }
       }
     CleanupStack::PopAndDestroy(2); // buff, lBuf		
     }
   }
 CleanupStack::PopAndDestroy(2); // dirList, fileSession
 }