Code:
MCoeForegroundObserver::HandleLosingForeground()
{
  const TUid KNativeCameraAppUID = { 0x101ffa86}; //The UID of the native camera application

  TUid id( KNativeCameraAppUID);

  TApaTaskList taskList( CEikonEnv::Static()->WsSession() );

  TApaTask task = taskList.FindApp( id );

  if ( task.Exists() )  //If the native camera application is running
  {

          RWsSession WsSession = CCoeEnv::Static()->WsSession();

          TWsEvent event;

          TInt ForegroundWinGroup = WsSession.GetFocusWindowGroup();

          if (task.WgId()==ForegroundWinGroup)   //If the native camera application is on the foreground
          {

               const TUid KCurrentAppUID = { 0x20004A79 }; //The UID of current runing application

               TUid thisid( KCurrentAppUID );

               TApaTaskList taskList1( CEikonEnv::Static()->WsSession() );

               TApaTask task1 = taskList1.FindApp( thisid );

               if ( task1.Exists() )
               {
                      task1.BringToForeground();
               }
          }
    }
}