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/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the Qt Mobility Components.
**
** $QT_BEGIN_LICENSE:LGPL$
** GNU Lesser General Public License Usage
** This file may be used under the terms of the GNU Lesser General Public
** License version 2.1 as published by the Free Software Foundation and
** appearing in the file LICENSE.LGPL included in the packaging of this
** file. Please review the following information to ensure the GNU Lesser
** General Public License version 2.1 requirements will be met:
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU General
** Public License version 3.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of this
** file. Please review the following information to ensure the GNU General
** Public License version 3.0 requirements will be met:
** http://www.gnu.org/copyleft/gpl.html.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "qlandmarkdbeventhandler.h"
#include <qdebug.h>
CLandmarkDbEventHandler::CLandmarkDbEventHandler() :
CActive(EPriorityStandard)
{
// No implementation
}
/*
* This should be called before any use, it initializes all the required objects
*/
void CLandmarkDbEventHandler::InitializeL()
{
TInt err = KErrNone;
iDatabase = CPosLandmarkDatabase::OpenL();
err = iObserverLock.CreateLocal(EOwnerProcess);
User::LeaveIfError(err);
CActiveScheduler::Add(this);
// Acquire the lock, this is required as the observers cannot modified
// when the observer list is being used
iObserverLock.Wait();
StartListening();
// release the lock
iObserverLock.Signal();
iIsInitialized = ETrue;
}
/*
* StartListening() is called to start listening to the database event
* It has to be protected by the iObserverLock. It is not taken inside this function
* for performance reasons.
*/
void CLandmarkDbEventHandler::StartListening()
{
//qDebug() << "starting database event notification";
// If there is atleast one observer and no request already pending
// then request for notification
if (iObserverList.Count() > 0 && !IsActive()) {
iDatabase->NotifyDatabaseEvent(iEvent, iStatus);
//qDebug() << "CLandmarkDbEventHandler::StartListening => SetActive";
SetActive();
}
}
/*
* Default Destructor
* This is not called on winscw emulator, as it is static object
*/
CLandmarkDbEventHandler::~CLandmarkDbEventHandler()
{
//qDebug() << "CLandmarkDbEventHandler::~CLandmarkDbEventHandler - start";
Cancel();
iObserverLock.Close();
iObserverList.Close();
delete iDatabase;
//qDebug() << "CLandmarkDbEventHandler::~CLandmarkDbEventHandler - finish";
}
/*
* Called by ActiveScheduler when an event occurs on this active object,
* i.e., when a landmark database event occurs
*/
void CLandmarkDbEventHandler::RunL()
{
//qDebug() << "CLandmarkDbEventHandler::RunL() start";
// If the event completed successfully
if (iStatus.Int() == KErrNone) {
// Acquire the lock, this is required as the observers cannot modified
// when the observer list is being used
iObserverLock.Wait();
// Iterate through all the registered observers and call handleDatabaseEvent
for (TInt i = 0; i < iObserverList.Count(); i++) {
// Call the observer and indicate the event occurred
//qDebug() << "Notifying " << i+1 << " observer";
iObserverList[i]->handleDatabaseEvent(iEvent);
}
// Request for database notification again
StartListening();
// release the lock
iObserverLock.Signal();
}
//qDebug() << "CLandmarkDbEventHandler::RunL() end";
}
void CLandmarkDbEventHandler::DoCancel()
{
//qDebug() << "CLandmarkDbEventHandler::DoCancel, stopping database event notification";
// Cancel landmark database notification request
iDatabase->CancelNotifyDatabaseEvent();
//qDebug() << "CLandmarkDbEventHandler::DoCancel - finish";
}
/*
* AddObserver is used to add an observer, the observer will be notified upon
* database event completion
* The observer derives from MLandmarkDbEventObserver class
*/
TInt CLandmarkDbEventHandler::AddObsever(MLandmarkDbEventObserver* aObserverHandle)
{
//qDebug() << "Adding Observer - start ";
if (!iIsInitialized) {
TRAPD(err,InitializeL());
if (err) {
return err;
}
}
// Acquire the lock, this is required as the observers cannot be added,
// when the observer list is being used
iObserverLock.Wait();
TInt ret = iObserverList.InsertInAddressOrder(aObserverHandle);
// release the lock
StartListening();
iObserverLock.Signal();
//qDebug() << "Adding Observer - end, ret = " << ret;
return ret;
}
/*
* AddObserver is used to remove an observer, the observer will be notified upon
* database event completion
* The observer derives from MLandmarkDbEventObserver class
*/
TInt CLandmarkDbEventHandler::RemoveObsever(MLandmarkDbEventObserver* aObserverHandle)
{
//qDebug() << "Removing Observer - start";
if (!iIsInitialized) {
TRAPD(err,InitializeL());
if (err) {
return err;
}
}
//qDebug() << "start the lock";
// Acquire the lock, this is required as the observers cannot be removed,
// when the observer list is being used
iObserverLock.Wait();
// Find the observer in the list
TInt index = iObserverList.FindInAddressOrder(aObserverHandle);
if (index != KErrNotFound) {
// Remove the observer if found
iObserverList.Remove(index);
iObserverList.Compress();
// this is done to reuse index for return value, note index does not contain error code
// if successful, hece this is required
index = KErrNone;
}
// release the lock
//qDebug() << "release the lock";
iObserverLock.Signal();
if (iObserverList.Count() <= 0 && IsActive()){
Cancel();
}
//qDebug() << "Removing Observer - end, index = " << index;
return index;
}
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