diff -r 000000000000 -r ba25891c3a9e ncdengine/inc/ncdnodecontainer.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/ncdengine/inc/ncdnodecontainer.h Thu Dec 17 08:51:10 2009 +0200 @@ -0,0 +1,137 @@ +/* +* Copyright (c) 2006 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: Contains MNcdNodeContainer interface +* +*/ + + +#ifndef M_NCD_NODE_CONTAINER_H +#define M_NCD_NODE_CONTAINER_H + + +#include + +#include "catalogsbase.h" +#include "ncdinterfaceids.h" +#include "ncdchildloadmode.h" +#include "ncdcontainertype.h" + + +class MNcdNode; +class MNcdLoadNodeOperation; +class MNcdLoadNodeOperationObserver; + +/** + * Container may contain other nodes. + * This interface provides functions that can be used to + * get the nodes of the container. Also, a convenience function + * to load the content for the child nodes is provided. + * + * This interface can be queried from node objects that are containers, + * after the node has been initialized. + * + * + */ +class MNcdNodeContainer : public virtual MCatalogsBase + { + +public: + + /** + * Unique identifier for the interface, required for all MCatalogsBase interfaces. + * + * + */ + enum { KInterfaceUid = ENcdNodeContainerUid }; + + /** + * Returns the child node count for this container. The count may be + * used to get the upper limit for indexing the contained child nodes + * with the ChildL() method. + * + * @return The number of the children in this container. + */ + virtual TInt ChildCount() const = 0; + + + /** + * Returns a child (contained node) of this container. + * + * @note The reference count of the node is increased by one. So, + * Release function of the node should be called when the node + * is not needed anymore. + * + * @param aIndex is the index to the child of this container. + * @return Pointer to the child node, may be an item or another container. + * Counted, Release() must be called after use. + * @exception Leave System wide error code. + * @exception Panic ENcdPanicIndexOutOfRange Index out of range. + */ + virtual MNcdNode* ChildL( TInt aIndex ) = 0; + + + /** + * Loads node information from the content provider for the + * children of this container. + * + * The loading of children is started from the given index. + * Size informs the maximum number of children that are loaded. + * + * @param aIndex The index of the child that will be the first one + * to be loaded. + * @param aSize The maximum number of children to load. + * For special cases: if KMaxTInt is given, then it will be + * interpreted so that all the children after aIndex should be loaded. + * By using KMaxTInt, a parent container refresh may be skipped and + * all the children may be requested from server even if parent's + * child count information may not be valid. In normal cases, usage of + * KMaxTInt should be avoided. Instead, refresh the parent first and + * use the correct child count value. KMaxTInt may not be supported + * for all type of containers. If not supported, then a leave will occur. + * @param aMode Load mode, determines whether structure, metadata or both + * will be loaded. + * @param aObserver Observer for the operation. + * @return Pointer to an operation that can + * be used to check the progressing of the loading. Counted, + * Release() must be called after use. + * @exception Leave System wide error code. + * KErrNotFound if trying to load metadata and no structure is present. + * KNcdErrorParallelOperationNotAllowed if a parallel client is running + * an operation for the same metadata, see MNcdOperation for full explanation. + */ + virtual MNcdLoadNodeOperation* LoadChildrenL( + TInt aIndex, TInt aSize, TNcdChildLoadMode aMode, + MNcdLoadNodeOperationObserver& aObserver ) = 0; + + /** + * Tells the type of the folder. It may be a normal folder or a catalog. + * + * @return The type. + */ + virtual TNcdContainerType ContainerType() const = 0; + + +protected: + + /** + * Destructor. + * + * @see MCatalogsBase::~MCatalogsBase + */ + virtual ~MNcdNodeContainer() {} + + }; + + +#endif // M_NCD_NODE_CONTAINER_H