1 /*

     2 * Copyright (c) 2006 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:   Notifies observers of external changes to the calendar database

    15 *

    16 */

    17 

    18 

    19 

    20 //debug

    21 #include "calendarui_debug.h"

    22 

    23 // INCLUDE FILES

    24 #include "calendbchangenotifier.h"    // CCalenDbChangeNotifier

    25 #include "calenglobaldata.h"            // Calendar global data

    26 #include <calsession.h>                 // CalSession

    27 

    28 // -----------------------------------------------------------------------------

    29 // KTimerResolution limits the number of notifications sent to registered

    30 // MCalenDBChangeObserver instances.  Notifications may come from 

    31 // MCalChangeCallBack2 at a very high rate which could impact performance, 

    32 // for example by causing constant view refreshes.

    33 // CCalenDbChangeNotifier notifies observers when KTimerResolution has elapsed

    34 // since the last notification was received from MCalChangeCallBack2

    35 // -----------------------------------------------------------------------------

    36 const TInt KTimerResolution = 1000000;  // 1 Second

    37 

    38 // ============================ MEMBER FUNCTIONS ===============================

    39 

    40 // -----------------------------------------------------------------------------

    41 // CCalenDbChangeNotifier::CCalenDbChangeNotifier

    42 // C++ default constructor can NOT contain any code, that might leave.

    43 // (other items were commented in a header).

    44 // -----------------------------------------------------------------------------

    45 CCalenDbChangeNotifier::CCalenDbChangeNotifier( CCalenGlobalData& aGlobalData ) 

    46     : CActive( EPriorityNormal ),

    47       iGlobalData( aGlobalData )

    48     {

    49     TRACE_ENTRY_POINT;

    50 

    51     iRestartTimer = EFalse;

    52 

    53     TRACE_EXIT_POINT;

    54     }

    55 

    56 // -----------------------------------------------------------------------------

    57 // CCalenDbChangeNotifier::NewL

    58 // Two-phased constructor.

    59 // (other items were commented in a header).

    60 // -----------------------------------------------------------------------------

    61 CCalenDbChangeNotifier* CCalenDbChangeNotifier::NewL( CCalenGlobalData& aGlobalData )

    62     {

    63     TRACE_ENTRY_POINT;

    64 

    65     CCalenDbChangeNotifier* self = new( ELeave ) CCalenDbChangeNotifier( aGlobalData );

    66     CleanupStack::PushL( self );

    67     self->ConstructL();

    68     CleanupStack::Pop( self );

    69 

    70     TRACE_EXIT_POINT;

    71     return self;

    72     }

    73 

    74 // -----------------------------------------------------------------------------

    75 // CCalenDbChangeNotifier::ConstructL

    76 // Symbian 2nd phase constructor can leave.

    77 // (other items were commented in a header).

    78 // -----------------------------------------------------------------------------

    79 void CCalenDbChangeNotifier::ConstructL()

    80     {

    81     TRACE_ENTRY_POINT;

    82 

    83     // We want to receive notifications for the full agenda date range

    84     TCalTime start, end;

    85     start.SetTimeUtcL( TCalTime::MinTime() );

    86     end.SetTimeUtcL( TCalTime::MaxTime() );

    87     CalCommon::TCalTimeRange range( start, end ); 

    88 

    89     // Create a notification filter

    90     iCalChangeFilter = CCalChangeNotificationFilter::NewL(

    91                                                         MCalChangeCallBack2::EChangeEntryAll, 

    92                                                         ETrue, 

    93                                                         range );

    94 

    95     // Enable database change notifications on current global data session

    96     iGlobalData.CalSessionL().StartChangeNotification( *this, *iCalChangeFilter );

    97 

    98     // Create a timer to limit the number of notifications broadcast

    99     iNotificationTimer.CreateLocal();

   100 

   101     // Active object, add to active scheduler

   102     CActiveScheduler::Add( this );

   103 

   104     TRACE_EXIT_POINT;

   105     }

   106 

   107 // -----------------------------------------------------------------------------

   108 // CCalenDbChangeNotifier::~CCalenDbChangeNotifier

   109 // Destructor

   110 // (other items were commented in a header).

   111 // -----------------------------------------------------------------------------

   112 CCalenDbChangeNotifier::~CCalenDbChangeNotifier()

   113     {

   114     TRACE_ENTRY_POINT;

   115 

   116     Cancel();

   117     // Reset the observer array.  Array contents are NOT owned by this class

   118     iDBObservers.Reset();

   119 

   120     iNotificationTimer.Close();

   121 

   122     // Disable database change notifications on current global data session   

   123     PIM_TRAPD_HANDLE( iGlobalData.CalSessionL().StopChangeNotification() );

   124 

   125     // Destroy the notification filter

   126     delete iCalChangeFilter;

   127     

   128     TRACE_EXIT_POINT;    

   129     }

   130 

   131 // -----------------------------------------------------------------------------

   132 // CCalenDbChangeNotifier::LastDBModificationTime

   133 // Returns the time of the last database change notification.  This may not be

   134 // the time of the last notification sent to MCalenDBChangeObservers.

   135 // (other items were commented in a header).

   136 // -----------------------------------------------------------------------------

   137 TTime CCalenDbChangeNotifier::LastDBModificationTime() const

   138     {

   139     TRACE_ENTRY_POINT;

   140 

   141     TRACE_EXIT_POINT;

   142     return iLastDbChangeNotification;

   143     }

   144 

   145 // -----------------------------------------------------------------------------

   146 // CCalenDbChangeNotifier::CalChangeNotification

   147 // Called when a change to the agenda database occurs from a different session

   148 // to the one we are currently using.

   149 // (other items were commented in a header).

   150 // -----------------------------------------------------------------------------

   151 void CCalenDbChangeNotifier::CalChangeNotification( RArray<TCalChangeEntry>& /*aChangeItems*/ )

   152     {

   153     TRACE_ENTRY_POINT;

   154 

   155     // Always update the last notification time, even if we don't notify 

   156     // our observers

   157     iLastDbChangeNotification.UniversalTime();

   158     if( !IsActive() )

   159         {

   160         iNotificationTimer.After( iStatus, KTimerResolution );

   161         SetActive();

   162         }

   163     else

   164         {

   165         iRestartTimer = ETrue;

   166         iNotificationTimer.Cancel();

   167         }

   168 

   169     TRACE_EXIT_POINT;

   170     }

   171 

   172 // -----------------------------------------------------------------------------

   173 // CCalenDbChangeNotifier::RegisterObserverL

   174 // Adds the passed observer to the observer array.  All observers in the array 

   175 // will be notified of changes to the agenda database.

   176 // (other items were commented in a header).

   177 // -----------------------------------------------------------------------------    

   178  void CCalenDbChangeNotifier::RegisterObserverL( MCalenDBChangeObserver& aDBObserver )

   179     {

   180     TRACE_ENTRY_POINT;

   181 

   182     iDBObservers.Append( &aDBObserver );

   183 

   184     TRACE_EXIT_POINT;

   185     }

   186 

   187 // -----------------------------------------------------------------------------

   188 // CCalenDbChangeNotifier::DeRegisterObserverL

   189 // Removes the passed observer to the observer array.  All observers in the array 

   190 // will be notified of changes to the agenda database.

   191 // -----------------------------------------------------------------------------       

   192 void CCalenDbChangeNotifier::DeRegisterObserverL( MCalenDBChangeObserver& aDBObserver )

   193     {

   194     TRACE_ENTRY_POINT;

   195 

   196     for( TInt x = 0; x < iDBObservers.Count(); ++x )

   197         {

   198         if( iDBObservers[x] == &aDBObserver )

   199             {

   200             iDBObservers.Remove( x );

   201             return;

   202             }

   203         }

   204     User::Leave( KErrNotFound );

   205 

   206     TRACE_EXIT_POINT;

   207     }

   208 

   209 // -----------------------------------------------------------------------------       

   210 // CCalenDbChangeNotifier::RunL

   211 // From CActive::RunL

   212 // Called when notification timer expires

   213 // (other items were commented in a header).

   214 // -----------------------------------------------------------------------------       

   215 void CCalenDbChangeNotifier::RunL()

   216     {

   217     TRACE_ENTRY_POINT;

   218 

   219     switch( iStatus.Int() )

   220         {

   221         case KErrCancel:

   222             {

   223             // The normal reason for the timer being cancelled is another

   224             // database change.  Restart the timer.

   225             if( iRestartTimer )

   226                 {

   227                 iRestartTimer = EFalse;

   228                 iNotificationTimer.After( iStatus, KTimerResolution );

   229                 SetActive();

   230                 }        

   231             }

   232         break;

   233 

   234         case KErrNone:

   235             {

   236             //Timer completion, notify observers

   237             for( TInt x = 0; x < iDBObservers.Count(); ++x )

   238                 {

   239                 iDBObservers[x]->HandleDBChangeL();

   240                 }

   241             }

   242         break;

   243 

   244         default:

   245             {

   246             User::Leave( KErrArgument );

   247             }

   248         break;

   249         }

   250 

   251     TRACE_EXIT_POINT;

   252     }

   253 

   254 // -----------------------------------------------------------------------------       

   255 // CCalenDbChangeNotifier::RunError

   256 // From CActive::RunError

   257 // (other items were commented in a header).

   258 // -----------------------------------------------------------------------------

   259 TInt CCalenDbChangeNotifier::RunError( TInt aError )

   260     {

   261     TRACE_ENTRY_POINT;

   262 

   263     //RunL leaving means that the view could not be refreshed.

   264     //Theres not much we can do except be ready for the next database event.

   265     iRestartTimer = EFalse;

   266 

   267     TRACE_EXIT_POINT;

   268     return aError;

   269     }

   270 

   271 // -----------------------------------------------------------------------------       

   272 // CCalenDbChangeNotifier::DoCancel

   273 // From CActive::DoCancel

   274 // (other items were commented in a header).

   275 // -----------------------------------------------------------------------------

   276 void CCalenDbChangeNotifier::DoCancel()

   277     {

   278     TRACE_ENTRY_POINT;

   279 

   280     // Stop the notification timer

   281     iRestartTimer = EFalse;

   282     iNotificationTimer.Cancel();

   283 

   284     TRACE_EXIT_POINT;

   285     }

   286 

   287 // End of File