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#ifndef INCLUDED_SVX_SOURCE_ACCESSIBILITY_CHILDRENMANAGERIMPL_HXX
#define INCLUDED_SVX_SOURCE_ACCESSIBILITY_CHILDRENMANAGERIMPL_HXX
#include <svx/AccessibleShape.hxx>
#include <svx/IAccessibleViewForwarderListener.hxx>
#include <svx/IAccessibleParent.hxx>
#include <svx/AccessibleShapeTreeInfo.hxx>
#include <editeng/AccessibleContextBase.hxx>
#include <comphelper/compbase.hxx>
#include <tools/gen.hxx>
#include <vector>
#include <com/sun/star/drawing/XShape.hpp>
#include <com/sun/star/drawing/XShapes.hpp>
#include <com/sun/star/document/XEventListener.hpp>
#include <com/sun/star/view/XSelectionChangeListener.hpp>
#include <com/sun/star/accessibility/XAccessible.hpp>
namespace accessibility {
class ChildDescriptor;
// See below for declaration.
typedef ::std::vector<ChildDescriptor> ChildDescriptorListType;
// Re-using MutexOwner class defined in AccessibleContextBase.hxx
/** This class contains the actual implementation of the children manager.
<p>It maintains a set of visible accessible shapes in
<member>maVisibleChildren</member>. The objects in this list stem from
two sources. The first is a list of UNO shapes like the list of shapes
in a draw page. A reference to this list is held in
<member>maShapeList</member>. Accessible objects for these shapes are
created on demand. The list can be replaced by calls to the
<member>SetShapeList</member> method. The second source is a list of
already accessible objects. It can be modified by calls to the
<member>AddAccessibleShape</member> and
<member>ClearAccessibleShapeList</member> methods.</p>
<p>Each call of the <member>Update</member> method leads to a
re-calculation of the visible shapes which then can be queried with the
<member>GetChildCount</member> and <member>GetChild</member> methods.
Events are sent informing all listeners about the removed shapes which are
not visible anymore and about the added shapes.</p>
<p> The visible area which is used to determine the visibility of the
shapes is taken from the view forwarder. Thus, to signal a change of
the visible area call <member>ViewForwarderChanged</member>.</p>
<p>The children manager adds itself as disposing() listener at every UNO
shape it creates an accessible object for so that when the UNO shape
passes away it can dispose() the associated accessible object.</p>
@see ChildrenManager
*/
class ChildrenManagerImpl final
:
public comphelper::WeakComponentImplHelper<
css::document::XEventListener,
css::view::XSelectionChangeListener>,
public IAccessibleViewForwarderListener,
public IAccessibleParent
{
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.
*/
ChildrenManagerImpl (css::uno::Reference<css::accessibility::XAccessible> xParent,
css::uno::Reference<css::drawing::XShapes> xShapeList,
const AccessibleShapeTreeInfo& rShapeTreeInfo,
AccessibleContextBase& rContext);
/** If there still are managed children these are disposed and
released.
*/
virtual ~ChildrenManagerImpl() override;
/** Do that part of the initialization that you can not or should not do
in the constructor like registering at broadcasters.
*/
void Init();
/** Return the number of currently visible accessible children.
@return
If there are no children a 0 is returned.
*/
sal_Int64 GetChildCount()
const noexcept;
/// @throws css::uno::RuntimeException
/// @throws css::lang::IndexOutOfBoundsException
const css::uno::Reference<css::drawing::XShape>& GetChildShape(sal_Int64 nIndex);
/** 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 (sal_Int64 nIndex);
/** Return the requested accessible child.
@param aChildDescriptor
This object contains references to the original shape and its
associated accessible object.
@param _nIndex
The index which will be used in getAccessibleIndexInParent of the accessible shape.
@return
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 css::uno::RuntimeException
*/
css::uno::Reference<css::accessibility::XAccessible>
GetChild (ChildDescriptor& aChildDescriptor,sal_Int32 _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 </true> then accessible objects associated with the visible
shapes are created only when asked for. No event is sent on
creation. If </false> 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);
/** Set the list of UNO shapes to the given list. This removes the old
list and does not add to it. The list of accessible shapes that is
build up by calls to <member>AddAccessibleShape</member> is not
modified. Neither is the list of visible children. Accessible
objects are created on demand.
@param xShapeList
The list of UNO shapes that replaces the old list.
*/
void SetShapeList (
const css::uno::Reference<css::drawing::XShapes>& xShapeList);
/** Add an accessible shape. This does not modify the list of UNO shapes
or the list of visible shapes. Accessible shapes are, at the
moment, not tested against the visible area but are always appended
to the list of visible children.
@param shape
The new shape that is added to the list of accessible shapes; must
be non-null.
*/
void AddAccessibleShape (rtl::Reference<AccessibleShape>
const & shape);
/** Clear the lists of accessible shapes and that of visible accessible
shapes. The list of UNO shapes is not modified.
*/
void ClearAccessibleShapeList();
/** Set 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 (
const AccessibleShapeTreeInfo& rShapeTreeInfo);
/** Update the SELECTED and FOCUSED states of all visible children
according to the given selection. This includes setting
<em>and</em> resetting the states.
*/
void UpdateSelection();
/** Return whether one of the shapes managed by this object has
currently the focus.
@return
Returns <true/> when there is a shape that has the focus and
<false/> when there is no such shape.
*/
bool HasFocus()
const;
/** When there is a shape that currently has the focus,
i.e. <member>HasFocus()</member> returns <true/> then remove the
focus from that shape. Otherwise nothing changes.
*/
void RemoveFocus();
// lang::XEventListener
virtual void SAL_CALL
disposing (
const css::lang::EventObject& rEventObject) override;
// document::XEventListener
virtual void SAL_CALL
notifyEvent (
const css::document::EventObject& rEventObject) override;
// view::XSelectionChangeListener
virtual void SAL_CALL
selectionChanged (
const css::lang::EventObject& rEvent) override;
// IAccessibleViewForwarderListener
/** Informs this children manager and its children about a change of one
(or more) aspect of the view forwarder.
@param aChangeType
A change type of <const>VISIBLE_AREA</const> leads to a call to
the <member>Update</member> which creates accessible objects of
new shapes immediately. Other change types are passed to the
visible accessible children without calling
<member>Update</member>.
@param pViewForwarder
The modified view forwarder. Use this one from now on.
*/
virtual void ViewForwarderChanged() override;
// IAccessibleParent
/** Replace the specified child with a replacement.
@param pCurrentChild
This child is to be replaced.
@param pReplacement
The replacement for the current child.
@return
The returned value indicates whether the replacement has been
finished successfully.
*/
virtual bool ReplaceChild (
AccessibleShape* pCurrentChild,
const css::uno::Reference< css::drawing::XShape >& _rxShape,
const tools::
Long _nIndex,
const AccessibleShapeTreeInfo& _rShapeTreeInfo
) override;
// Add the impl method for IAccessibleParent interface
virtual AccessibleControlShape* GetAccControlShapeFromModel
(css::beans::XPropertySet* pSet) override;
virtual AccessibleShape*
GetAccessibleCaption (
const css::uno::Reference<css::drawing::XShape>& xShape) ove
rride;
private:
/** This list holds the descriptors of all currently visible shapes and
associated accessible object.
<p>With the descriptors it maintains a mapping of shapes to
accessible objects. It acts as a cache in that accessible objects
are only created on demand and released with every update (where the
latter may be optimized by the update methods).<p>
<p>The list is realized as a vector because it remains unchanged
between updates (i.e. complete rebuilds of the list) and allows a
fast (constant time) access to its elements for given indices.</p>
*/
ChildDescriptorListType maVisibleChildren;
/** The original list of UNO shapes. The visible shapes are inserted
into the list of visible children
<member>maVisibleChildren</member>.
*/
css::uno::Reference<css::drawing::XShapes> mxShapeList;
/** This list of additional accessible shapes that can or shall not be
created by the shape factory.
*/
typedef std::vector< rtl::Reference< AccessibleShape> > AccessibleShapeList;
AccessibleShapeList maAccessibleShapes;
/** Rectangle that describes the visible area in which a shape has to lie
at least partly, to be accessible through this class. Used to
detect changes of the visible area after changes of the view forwarder.
*/
tools::Rectangle maVisibleArea;
/** The parent of the shapes. It is used for creating accessible
objects for given shapes.
*/
css::uno::Reference<css::accessibility::XAccessible> mxParent;
/** Bundle of information passed down the shape tree.
*/
AccessibleShapeTreeInfo maShapeTreeInfo;
/** Reference to an accessible context object that is used to inform its
listeners of new and removed children.
*/
AccessibleContextBase& mrContext;
/** This method is called from the component helper base class while
disposing.
*/
virtual void disposing(std::unique_lock<std::mutex>&) override;
void impl_dispose();
ChildrenManagerImpl (const ChildrenManagerImpl&) = delete;
ChildrenManagerImpl& operator= (const ChildrenManagerImpl&) = delete;
/** This member points to the currently focused shape. It is NULL when
there is no focused shape.
*/
AccessibleShape* mpFocusedShape;
/** Three helper functions for the <member>Update</member> method.
*/
/** Create a list of visible shapes from the list of UNO shapes
<member>maShapeList</member> and the list of accessible objects.
@param raChildList
For every visible shape from the two sources mentioned above one
descriptor is added to this list.
*/
void CreateListOfVisibleShapes (ChildDescriptorListType& raChildList);
/** From the old list of (former) visible shapes remove those that
are not member of the new list. Send appropriate events for every
such shape.
@param raNewChildList
The new list of visible children against which the old one
is compared.
@param raOldChildList
The old list of visible children against which the new one
is compared.
*/
void RemoveNonVisibleChildren (
const std::vector<ChildDescriptor*>& rNonVisibleChildren);
/** Merge the information that is already known about the visible shapes
from the old list into the current list, and return a list of
children that are in the old list, but not the current one.
@param raChildList
Information is merged to the current list of visible children
from this list. The old list can get reordered.
@return
Vector of children that are in the old list, but not the current
one.
*/
std::vector<ChildDescriptor*> MergeAccessibilityInformation (ChildDescriptorListType& raChildList);
/** If the visible area has changed then send events that signal a
change of their bounding boxes for all shapes that are members of
both the current and the new list of visible shapes.
@param raChildList
Events are sent to all entries of this list that already contain
an accessible object.
*/
static void SendVisibleAreaEvents (ChildDescriptorListType& raChildList);
/** If children have to be created immediately and not on demand the
create the missing accessible objects now.
@param raDescriptorList
Create an accessible object for every member of this list where
that object does not already exist.
*/
void CreateAccessibilityObjects (ChildDescriptorListType& raChildList);
/** Add a single shape. Update all relevant data structures
accordingly. Use this method instead of <member>Update()</member>
when only a single shape has been added.
*/
void AddShape (const css::uno::Reference<css::drawing::XShape>& xShape);
/** Remove a single shape. Update all relevant data structures
accordingly. Use this method instead of <member>Update()</member>
when only a single shape has been removed.
*/
void RemoveShape (const css::uno::Reference<css::drawing::XShape>& xShape);
/** Add the children manager as dispose listener at the given shape so
that the associated accessible object can be disposed when the shape
is disposed.
@param xShape
Register at this shape as dispose listener.
*/
void RegisterAsDisposeListener (const css::uno::Reference<css::drawing::XShape>& xShape);
/** Remove the children manager as dispose listener at the given shape
@param xShape
Unregister at this shape as dispose listener.
*/
void UnregisterAsDisposeListener (const css::uno::Reference<css::drawing::XShape>& ;xShape);
};
/** A child descriptor holds a reference to a UNO shape and the
corresponding accessible object. There are two use cases:
<ol><li>The accessible object is only created on demand and is then
initially empty.</li>
<li>There is no UNO shape. The accessible object is given as argument
to the constructor.</li>
</ol>
In both cases the child descriptor assumes ownership over the accessible
object.
*/
class ChildDescriptor
{
public:
/** Reference to a (partially) visible shape.
*/
css::uno::Reference<css::drawing::XShape> mxShape;
/** The corresponding accessible object. This reference is initially
empty and only replaced by a reference to a new object when that is
requested from the outside.
*/
rtl::Reference<AccessibleShape> mxAccessibleShape;
/** Return a pointer to the implementation object of the accessible
shape of this descriptor.
@return
The result is NULL if either the UNO reference to the accessible
shape is empty or it can not be transformed into a pointer to
the desired class.
*/
AccessibleShape* GetAccessibleShape() const { return mxAccessibleShape.get(); }
/** set the index _nIndex at the accessible shape
@param _nIndex
The new index in parent.
*/
void setIndexAtAccessibleShape(sal_Int32 _nIndex);
/** This flag is set during the visibility calculation and indicates
that at one time in this process an event is sent that informs the
listeners of the creation of a new accessible object. This flags is
not reset afterwards. Don't use it unless you know exactly what you
are doing.
*/
bool mbCreateEventPending;
/** Create a new descriptor for the specified shape with empty reference
to accessible object.
*/
explicit ChildDescriptor (const css::uno::Reference<css::drawing::XShape>& xShape);
/** Create a new descriptor for the specified shape with empty reference
to the original shape.
*/
explicit ChildDescriptor (const rtl::Reference<AccessibleShape>& rxAccessibleShape);
/** Dispose the accessible object of this descriptor. If that object
does not exist then do nothing.
@param rParent
The parent of the accessible object to dispose. A child event
is sent in its name.
*/
void disposeAccessibleObject (AccessibleContextBase& rParent);
/** Compare two child descriptors. Take into account that a child
descriptor may be based on a UNO shape or, already, on an accessible
shape.
*/
bool operator == (const ChildDescriptor& aDescriptor) const
{
return (
this == &aDescriptor ||
(
(mxShape.get() == aDescriptor.mxShape.get() ) &&
(mxShape.is() || mxAccessibleShape.get() == aDescriptor.mxAccessibleShape.get())
)
);
}
};
} // end of namespace accessibility
#endif
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
