/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ /* * This file is part of the LibreOffice project. * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. * * This file incorporates work covered by the following license notice: * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed * with this work for additional information regarding copyright * ownership. The ASF licenses this file to you under the Apache * License, Version 2.0 (the "License"); you may not use this file * except in compliance with the License. You may obtain a copy of * the License at http://www.apache.org/licenses/LICENSE-2.0 . */ #ifndef INCLUDED_SVX_CHILDRENMANAGER_HXX #define INCLUDED_SVX_CHILDRENMANAGER_HXX #include #include #include #include namespace com::sun::star { namespace accessibility { class XAccessible; } namespace drawing { class XShape; } namespace drawing { class XShapes; } } namespace accessibility { class AccessibleContextBase; class AccessibleShapeTreeInfo; class ChildrenManagerImpl; /** The AccessibleChildrenManager class acts as a cache of the accessible objects of the currently visible shapes of a draw page and as a factory to create the corresponding accessible object for a given shape.

There are two sources of shapes. The first is a list of UNO shapes. It is passes to the constructor and can be re-set with a call to SetShapeList. Accessibility objects which represent these shapes are constructed usually on demand. The second source is a set of single AccessibleShape objects added by calls to AddAccessibleShape. These are not modified by this class. They are only copied into the list of visible shapes depending on their visibility. The later list can be cleared by calling ClearAccessibleShapeList. The actual set of children accessible through the GetChildrenCount and GetChild methods are the accessible objects that lie completely or partially inside the visible area obtained from the view forwarder in the shape tree info.

A children manager registers itself at the broadcaster passed to its constructor and transforms/forwards the received events to the listeners of the also given context base. The transformation process includes interpreting a document::XEventListener, the change from XShape references to the associated XAccessible reference, and the creation of an XAccessibleEventObject. The event object is then passed to the fireEvent method of the context and from there forwarded to all listeners.

Note that some of the data given to the constructor is passed to the accessible shape objects created by that child manager which in turn pass these data to their child managers. The data is thus propagated down a tree of child managers/accessible shape objects from a top level class that is usually a document/model. This is the way to give all accessible objects access to data normally known only to the top level owner of the shapes.

*/ class SVX_DLLPUBLIC ChildrenManager final { public: /** Create a children manager, which manages the children of the given parent. The parent is used for creating accessible objects. The list of shapes for which to create those objects is not derived from the parent and has to be provided separately by calling one of the update methods. @param rxParent The parent of the accessible objects which will be created on demand at some point of time in the future. @param rxShapeList List of UNO shapes to manage. @param rShapeTreeInfo Bundle of information passed down the shape tree. @param rContext An accessible context object that is called for firing events for new and deleted children, i.e. that holds a list of listeners to be informed. */ ChildrenManager (const css::uno::Reference< css::accessibility::XAccessible>& rxParent, const css::uno::Reference< css::drawing::XShapes>& rxShapeList, const AccessibleShapeTreeInfo& rShapeTreeInfo, AccessibleContextBase& rContext); /** If there still are managed children these are marked as DEFUNC and released. */ ~ChildrenManager(); /** Return the number of currently visible accessible children. @return If there are no children a 0 is returned. */ long GetChildCount() const throw (); /** Return the requested accessible child or throw and IndexOutOfBoundsException if the given index is invalid. @param nIndex Index of the requested child. Call getChildCount for obtaining the number of children. @return In case of a valid index this method returns a reference to the requested accessible child. This reference is empty if it has not been possible to create the accessible object of the corresponding shape. @throws Throws an IndexOutOfBoundsException if the index is not valid. */ css::uno::Reference< css::accessibility::XAccessible> GetChild (long nIndex); /// @throws css::lang::IndexOutOfBoundsException /// @throws css::uno::RuntimeException css::uno::Reference< css::drawing::XShape> GetChildShape (long nIndex); /** Update the child manager. Take care of a modified set of children and modified visible area. This method can optimize the update process with respect separate updates of a modified children list and visible area. @param bCreateNewObjectsOnDemand If then accessible objects associated with the visible shapes are created only when asked for. No event is sent on creation. If then the accessible objects are created before this method returns and events are sent to inform the listeners of the new object. */ void Update (bool bCreateNewObjectsOnDemand = true); /** Replace the list of UNO shapes by the specified list. @param xShapeList The new list of shapes. */ void SetShapeList (const css::uno::Reference< css::drawing::XShapes>& xShapeList); /** Add an accessible shape. The difference to the UNO shapes in the list passed to the constructor the specified object does not have to be created by the shape factory. This gives the caller full control over object creation. @param shape must be non-null */ void AddAccessibleShape (css::uno::Reference const & shape); /** Clear the list of accessible shapes which have been added by previous calls to AddAccessibleShape. */ void ClearAccessibleShapeList(); /** Take a new event shape tree info. Call this method to inform the children manager of a change of the info bundle. @param rShapeTreeInfo The new info that replaces the current one. */ void SetInfo (AccessibleShapeTreeInfo const & rShapeTreeInfo); /** Update the SELECTED and FOCUSED states of all visible children according to the given selection. This includes setting and resetting the states. */ void UpdateSelection(); /** Return whether one of the shapes managed by this object has currently the focus. @return Returns when there is a shape that has the focus and when there is no such shape. */ bool HasFocus() const; /** When there is a shape that currently has the focus, i.e. HasFocus() returns then remove the focus from that shape. Otherwise nothing changes. */ void RemoveFocus(); void ViewForwarderChanged(); private: rtl::Reference mpImpl; ChildrenManager (const ChildrenManager&) = delete; ChildrenManager& operator= (const ChildrenManager&) = delete; }; } // end of namespace accessibility #endif /* vim:set shiftwidth=4 softtabstop=4 expandtab: */