--- /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 <e32cmn.h>
+
+#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