photosgallery/collectionframework/datasource/plugins/glxdatasourcemde2.5/inc/glxdatasourcetaskmds.h
/*
* Copyright (c) 2008-2009 Nokia Corporation and/or its subsidiary(-ies).
* All rights reserved.
* This component and the accompanying materials are made available
* under the terms of "Eclipse Public License v1.0"
* which accompanies this distribution, and is available
* at the URL "http://www.eclipse.org/legal/epl-v10.html".
*
* Initial Contributors:
* Nokia Corporation - initial contribution.
*
* Contributors:
*
* Description: Data source Task MDS Class
*
*/
#ifndef _C_GLXDATASOURCETASKMDS_H_
#define _C_GLXDATASOURCETASKMDS_H_
/**
* @author Simon Brooks, Alex Birkett
*/
// INCLUDES
#include <e32cmn.h>
#include <glxdatasource.h>
#include <glxdatasourcetask.h>
#include <glxfilterproperties.h>
#include <mdccommon.h>
#include <mdequery.h>
#include <mglxtnthumbnailcreatorclient.h>
#include <mpxfilter.h>
// FORWARD DECLARATIONS
class CGlxDataSourceMde;
class CGlxRequest;
class CGlxtnThumbnailCreator;
class CMdEObjectDef;
class CMdEObjectQuery;
class CMdESession;
/**
* Query types supported by subclasses of CGlxDataSourceTaskMde
*/
enum TGlxQueryType
{
EContainerFirstItemQuery, // CGlxDataSourceTaskMdeThumbnail+
EIdListQuery, // GlxDataSourceTaskMdeIdList
EAttributeQuery, // CGlxDataSourceTaskMdeAttribute
ELocationAttributeQuery, // CGlxDataSourceTaskMdeAttribute
EImageVideoQuery, // CGlxDataSourceTaskMdeAttribute (but should be general)
ECommandRemoveFromContainer, // CGlxDataSourceTaskMdeCommand
ECommandAddToContainer, // CGlxDataSourceTaskMdeCommand
ECommandRemoveLocation, // CGlxDataSourceTaskMdeCommand
ECommandAddContainer, // CGlxDataSourceTaskMdeCommand adds a container
ECommandDeleteContainers, // CGlxDataSourceTaskMdeCommand deletes containers objects
ECommandDeleteItems, // CGlxDataSourceTaskMdeCommand deletes containers objects
ECommandRenameContainer,
ECommandRename
};
/**
* CGlxDataSourceTaskMde class
* Base class for mde tasks: provides task generic functionality.
*/
NONSHARABLE_CLASS(CGlxDataSourceTaskMde) : public CGlxDataSourceTask,
public MMdEQueryObserver
{
public:
/**
* Constructor.
* @param aRequest request to be executed.
* @param aObserver observer to be informed when task has completed.
* @param aDataSource data source to be used by this object.
*/
CGlxDataSourceTaskMde(CGlxRequest* aRequest, MGlxDataSourceRequestObserver&
aObserver, CGlxDataSource* aDataSource);
/**
* Destructor.
*/
~CGlxDataSourceTaskMde();
/**
* Second stage constructor
*/
virtual void ConstructL();
protected: // to be implemented by deriving classes
/**
* See @ref CGlxDataSourceTask::ExecuteRequestL
*/
virtual void ExecuteRequestL() = 0;
/**
* Must be implemented by deriving classes. To handle query completion
* @param aQuery Query that has been completed.
*/
virtual void DoHandleQueryCompletedL(CMdEQuery& aQuery) = 0;
/**
* Optionally implemented by deriving classes. Used if the deriving class has
* to run more than one query. Should start the next query or call HandleRequestComplete()
* if no futher queries are required to be run. If the deriving class only has a single query,
* HandleRequestComplete() can be called from DoHandleQueryCompletedL()
*/
virtual void DoNextQueryL() {}
public: // From CGlxDataSourceTask
/**
* See @ref CGlxDataSourceTask::CancelRequest
*/
void CancelRequest();
private: // from MMdEQueryObserver
/**
* See @ref MMdEQueryObserver::HandleQueryNewResults
*/
void HandleQueryNewResults( CMdEQuery& aQuery,
TInt aFirstNewItemIndex,
TInt aNewItemCount );
/**
* See @ref MMdEQueryObserver::HandleQueryNewResults
*/
void HandleQueryNewResults( CMdEQuery& aQuery,
TInt aNewObjectItemCount,
TInt aNewRelationItemCount,
TInt aNewEventItemCount);
/**
* See @ref MMdEQueryObserver::HandleQueryCompleted
*/
void HandleQueryCompleted( CMdEQuery& aQuery, TInt aError);
protected:
/**
* Returns a pointer to the CGlxDataSourceMde object passed in on instantiation.
* @return a pointer to the CGlxDataSourceMde object passed in on instantiation.
*/
CGlxDataSourceMde* DataSource();
/**
* Set query contditions by container id and filter properties.
* @param aLogicCondition logic condition to add conditions to
* @param aContainerId Id of the container
* @param aContainerIsLeft. This should be set to to ETrue if the container is on the left side of the releation, or
* EFalse if the container is on the right side of the relation
*
*/
void SetQueryConditionsL(CMdEQuery& aQuery, const TGlxFilterProperties& aFilterProperties,
const TGlxMediaId aContainerId, CMdEObjectDef& aObjectDef);
void SetQueryFilterConditionsL(CMdELogicCondition& aLogicCondition, CMdEObjectDef& aObjectDef,
const TGlxFilterProperties& aFilterProperties);
void SetSortOrderL(CMdEQuery& aQuery, CMdEObjectDef& aObjectDef,
const TGlxFilterProperties& aFilterProperties);
/**
* Returns the maximum number of items that a query should find.
* @return Maximum number of results
*/
TInt MaxQueryResultsCount(const TGlxFilterProperties& aFilterProperties) const;
/**
* Removes and destroys the oldest query in iQueries.
*/
void RemoveQuery();
void DoQueryL(CMdEObjectDef& aObjectDef, TBool aIsContent, TGlxQueryType aQueryType,
TQueryResultMode aResultMode, const TGlxMediaId& aContainerId);
/**
* Adds queries for images and or videos to the query queue. The queries will return objects
* of type image or video that have ids specified by aObjectIds.
* @param aObjectIds A list of the ids of the required objects.
* @param aFilterProperties TGlxFilterProperties.iItemType is used to determine if only
* image or video queries are required if iItemType is not set to EGlxFilterImage or
* EGlxFitlerVideo a query for images will be queued first followed by a query for videos.
*/
void QueueImageVideoObjectQueriesL(const RArray<TGlxMediaId>& aObjectIds,
const TGlxFilterProperties& aFilterProperties);
/**
* Adds a query for tag objects that have ids specified by aObjectIds
* to the query queue.
* @param aObjectIds A list of the ids of the required objects.
*/
void QueueTagObjectQueryL(const RArray<TGlxMediaId>& aObjectIds);
/**
* Adds a query for album objects that have ids specified by aObjectIds
* to the query queue.
* @param aObjectIds A list of the ids of the required objects.
*/
void QueueAlbumObjectQueryL(const RArray<TGlxMediaId>& aObjectIds);
/**
* Adds a query for objects of type specified by aObjectDef
* that have ids specified by aObjectIds to the query queue.
* @param aObjectDef type of objects required.
* @param aObjectIds A list of the ids of the required objects.
* @param aQueryType The query type.
*/
void QueueObjectQueryL(CMdEObjectDef& aObjectDef,
const RArray<TGlxMediaId>& aObjectIds, const TGlxQueryType& aQueryType);
/**
* Appends a query to the query queue. (the ownership of the query is transferred)
* @param aQuery query to append to the query queue ownership is transferred to
* the query queue. It is expected that aQuery is not on the cleanupstack before the
* call to AppendQueryL is made
* @param aQueryType the query type.
*/
void AppendQueryL(CMdEQuery* aQuery, const TGlxQueryType& aQueryType);
/**
* Executes the query at ordinal 0 in the
* query list implementation can be overidden by
* deriving classes.
*/
virtual void ExecuteQueryL();
private:
/*
* Helper function TRAPed and called by HandleQueryCompleted()
* @param aQuery the query that has been completed
*/
void HandleQueryCompletedL(CMdEQuery& aQuery);
/**
* Removes the observer from any existing queries, cancels and destroys them
*/
void DestroyQueries();
private:
/**
* Default namespace def (not owned)
*/
CMdENamespaceDef* iDefaultNameSpaceDef;
protected:
/**
* Outstanding queries array (owned)
*/
RPointerArray <CMdEQuery> iQueries;
/**
* Query types array (owned)
*/
RArray <TGlxQueryType> iQueryTypes;
/**
* Filter properties
*/
TGlxFilterProperties iFilterProperties;
};
#endif //_C_GLXDATASOURCETASKMDS_H_