//------------------------------------------------------
//
// Patterns Implementation
//
//------------------------------------------------------
#region ProxyHwnd Methods
// ------------------------------------------------------
//
// Internal Methods
//
// ------------------------------------------------------
// Advises proxy that an event has been added.
// Maps the Automation Events into WinEvents and add those to the list of WinEvents notification hooks
internal virtual void AdviseEventAdded(AutomationEvent eventId, AutomationProperty [] aidProps)
{
// No RawElementBase creation callback, exit from here
if (_createOnEvent == null)
{
return;
}
int cEvents = 0;
WinEventTracker.EvtIdProperty [] aEvents;
// Gets an Array of WinEvents to trap on a per window handle basis
if (eventId == AutomationElement.AutomationPropertyChangedEvent)
{
aEvents = PropertyToWinEvent(aidProps, out cEvents);
}
else
{
aEvents = EventToWinEvent(eventId, out cEvents);
}
// If we have WinEvents to trap, add those to the list of WinEvent
// notification list
if (cEvents > 0)
{
WinEventTracker.AddToNotificationList(_hwnd, _createOnEvent, aEvents, cEvents);
}
}
// a client has stopped listening for an event on object(s) in the specified window.
internal void AdviseEventRemoved(IntPtr hwnd, AutomationEvent eventId, AutomationProperty[] properties)
{
// note: we don't need to worry about removing entries from our tables when windows are destroyed
//(EVENT_OBJECT_DESTROY with OBJID_WINDOW) because UIA already watches for this event and calls AdviseEventRemoved.
// use a lock to update our tables in one atomic operation.
lock (this)
{
// we should have a 2-nd level table for this hwnd...
if (_hwndTable.ContainsKey(hwnd))
{
Hashtable eventTable = (Hashtable)(_hwndTable[hwnd]);
// for the single event or each of possibly multiple properties decrement the reference count.
foreach (AutomationIdentifier key in EventKeys(eventId, properties))
{
// we should have an entry in the 2-nd level table for this event or property...
if (eventTable.ContainsKey(key))
{
// decrement the reference count
int refcount = (int)eventTable[key] - 1;
Debug.Assert(refcount >= 0);
if (refcount > 0)
{
eventTable[key] = refcount;
}
else
{
// if the refcount has gone to zero then remove this entry from the 2-nd level table.
eventTable.Remove(key);
// if this window doesn't have any more advises then remove it's entry from the top-level table
if (eventTable.Count == 0)
{
_hwndTable.Remove(hwnd);
// if there are no more advises then we can stop listening for WinEvents
if (_hwndTable.Count == 0)
{
//Debug.WriteLine("Stop listening for WinEvents.", "NativeMsaaProxy");
WinEventTracker.GetCallbackQueue().PostSyncWorkItem(new QueueItem.MSAAWinEventItem(StopListening));
}
}
}
}
else
{
Debug.WriteLine(string.Format(CultureInfo.CurrentCulture, "ERROR: AdviseEventRemoved called for {0} and event/property {1} without matching AdviseEventAdded.", hwnd, key), "NativeMsaaProxy");
}
}
}
else
{
Debug.WriteLine(string.Format(CultureInfo.CurrentCulture, "ERROR: AdviseEventRemoved called for {0} without matching AdviseEventAdded.", hwnd), "NativeMsaaProxy");
}
}
}
internal override void AdviseEventRemoved(
AutomationEvent eventId, AutomationProperty[] aidProps)
{
if (eventId == AutomationElementIdentifiers.AutomationPropertyChangedEvent &&
aidProps.Length > 0 &&
aidProps[0] == ScrollPatternIdentifiers.HorizontalScrollPercentProperty)
{
IntPtr upDownHwnd = GetUpDownHwnd();
if (upDownHwnd != IntPtr.Zero)
{
WinEventTracker.RemoveToNotificationList(
upDownHwnd, _upDownEvents, null, 1);
}
}
base.AdviseEventRemoved(eventId, aidProps);
}
internal override void AdviseEventRemoved(AutomationEvent eventId, AutomationProperty[] aidProps)
{
base.AdviseEventRemoved(eventId, aidProps);
// For now, ToolTips only raise ToolTip-specific events when they close
if (eventId != AutomationElement.ToolTipClosedEvent)
{
return;
}
if (_listenerCount > 0)
{
// decrement the event counter
--_listenerCount;
WinEventTracker.RemoveToNotificationList(IntPtr.Zero, _toolTipEventIds, new WinEventTracker.ProxyRaiseEvents(OnToolTipEvents), _toolTipEventIds.Length);
}
}
// a client is listening for an event on object(s) in the specified window.
internal void AdviseEventAdded(IntPtr hwnd, AutomationEvent eventId, AutomationProperty[] properties)
{
// When you start listening for events you listen for all events and then
// when you get the event you filter by any hwnd that got advised. But you have enough
// information when you get advised to listen only for in process where that hwnd resides.
// The SetWinEventHook api takes a process id, you could get the process id from the hwnd
// and limit the number of event you have to process.
// we have a two-level table structure. the top-level table maps an hwnd to another table.
// the second-level table maps an event (or a property in the case of property-changed-event)
// in that hwnd to a reference count of the number of clients listening for that event.
// use a lock to update our tables in one atomic operation.
lock (this)
{
// if we aren't listening for WinEvents then start listening.
if (_hwndTable.Count == 0)
{
//Debug.WriteLine("Starting listening for WinEvents.", "NativeMsaaProxy");
// Posting an item to the queue to start listening for WinEvents. This makes sure it is done on the proper thread
// Notably the same thread WinEventTracker uses, which guarantees the thread that SetWinEventHook is called on is
// actively pumping messages, which is required for SetWinEventHook to function properly.
WinEventTracker.GetCallbackQueue().PostSyncWorkItem(new QueueItem.MSAAWinEventItem(StartListening));
}
// if we already have a 2-nd level table for this hwnd then simply update the 2nd-level table.
// otherwise we need to create a 2-nd level table.
Hashtable eventTable;
if (_hwndTable.ContainsKey(hwnd))
{
eventTable = (Hashtable)(_hwndTable[hwnd]);
}
else
{
eventTable = new Hashtable();
_hwndTable[hwnd] = eventTable;
}
// for the single event or each of possibly multiple properties increment the reference counter.
foreach (AutomationIdentifier key in EventKeys(eventId, properties))
{
eventTable[key] = eventTable.ContainsKey(key) ? (int)eventTable[key] + 1 : 1;
}
}
}
internal override void AdviseEventAdded(
AutomationEvent eventId, AutomationProperty[] aidProps)
{
if (eventId == AutomationElementIdentifiers.AutomationPropertyChangedEvent &&
aidProps.Length > 0 &&
aidProps[0] == ScrollPatternIdentifiers.HorizontalScrollPercentProperty)
{
IntPtr upDownHwnd = GetUpDownHwnd();
if (upDownHwnd != IntPtr.Zero)
{
// Register for UpDown ValueChange WinEvents, which will be
// translated to scrolling events for the tab control.
WinEventTracker.AddToNotificationList(
upDownHwnd,
new WinEventTracker.ProxyRaiseEvents(UpDownControlRaiseEvents),
_upDownEvents, 1);
}
}
base.AdviseEventAdded(eventId, aidProps);
}
internal override void AdviseEventAdded(AutomationEvent eventId, AutomationProperty[] aidProps)
{
base.AdviseEventAdded(eventId, aidProps);
// If the framework is advising for ToolTipOpenedEvent then go ahead and raise this event now
// since the WinEvent we would listen to (usually EVENT_OBJECT_SHOW) has already occurrred
// (it is why Advise is being called). No other action is necessary because when this ToolTip
// goes away, AdviseEventRemoved is going to be called. In other words, this proxy gets
// created when the ToolTip opens and thrown away when it closes so no need to keep state
// that we want to listen for more SHOWS or CREATES - there's always one for any one instance.
if (eventId == AutomationElement.ToolTipOpenedEvent)
{
AutomationEventArgs e = new AutomationEventArgs(AutomationElement.ToolTipOpenedEvent);
AutomationInteropProvider.RaiseAutomationEvent(AutomationElement.ToolTipOpenedEvent, this, e);
}
else if (eventId == AutomationElement.ToolTipClosedEvent)
{
// subscribe to ToolTip specific events, keeping track of how many times the event has been added
WinEventTracker.AddToNotificationList(IntPtr.Zero, new WinEventTracker.ProxyRaiseEvents(OnToolTipEvents), _toolTipEventIds, _toolTipEventIds.Length);
_listenerCount++;
}
}
internal override void AdviseEventRemoved(AutomationEvent eventId, AutomationProperty [] aidProps)
{
// remove combo-related events
base.AdviseEventRemoved(eventId, aidProps);
NativeMethods.COMBOBOXINFO cbInfo = new NativeMethods.COMBOBOXINFO(NativeMethods.comboboxInfoSize);
if (GetComboInfo(_hwnd, ref cbInfo))
{
// remove edit and list specific events that got remapped into combo's events
if (eventId == AutomationElement.AutomationPropertyChangedEvent)
{
// ComboBoxEx32 controls with the style CBS_DROPDOWNLIST are still editable.
if (cbInfo.hwndItem != IntPtr.Zero && IsEditableCombo())
{
// un-subscribe from edit-specific notifications
// ValueAsString, ValueAsObject, IsReadOnly
// create array containing events from which user wants to unsubscribe
WinEventTracker.EvtIdProperty [] editPortionEvents;
int counter;
CreateEditPortionEvents(out editPortionEvents, out counter, aidProps);
if (counter > 0)
{
WinEventTracker.RemoveToNotificationList(cbInfo.hwndItem, editPortionEvents, null, counter);
}
}
}
// Need to also remove the advise from the list portions of the combobox.
if (cbInfo.hwndList != IntPtr.Zero)
{
WindowsListBox listbox = new WindowsListBox(cbInfo.hwndList, this, 0, true);
listbox.AdviseEventRemoved(eventId, aidProps);
}
}
}
// override the default implementation so we can handle the WinEvents that are send to the edit
// portion of ComboBox (Combo proxy will hide edit portion from the user, but will take care of all
// the features/functionality that Edit presents) and some(show, hide) events that are send to the List portion of combo
// In both cases this events will be presented to the user as Combo's LE events
internal override void AdviseEventAdded(AutomationEvent eventId, AutomationProperty [] aidProps)
{
// call the base class implementation first to add combo-specific things and register combo specific callback
base.AdviseEventAdded(eventId, aidProps);
NativeMethods.COMBOBOXINFO cbInfo = new NativeMethods.COMBOBOXINFO(NativeMethods.comboboxInfoSize);
if (GetComboInfo(_hwnd, ref cbInfo))
{
if (eventId == AutomationElement.AutomationPropertyChangedEvent)
{
// ComboBoxEx32 controls with the style CBS_DROPDOWNLIST are still editable.
if (cbInfo.hwndItem != IntPtr.Zero && IsEditableCombo())
{
// subscribe to edit-specific notifications, that would be presented as combo le event
// ValueAsString, ValueAsObject, IsReadOnly
// create array containing events that user is interested in
WinEventTracker.EvtIdProperty [] editPortionEvents;
int counter;
CreateEditPortionEvents(out editPortionEvents, out counter, aidProps);
if (counter > 0)
{
WinEventTracker.AddToNotificationList(cbInfo.hwndItem, new WinEventTracker.ProxyRaiseEvents(EditPortionEvents), editPortionEvents, counter);
}
}
}
// Need to also advise the list portions of the combobox so that it can raise events.
if (cbInfo.hwndList != IntPtr.Zero)
{
WindowsListBox listbox = new WindowsListBox(cbInfo.hwndList, this, 0, true);
listbox.AdviseEventAdded(eventId, aidProps);
}
}
}
private static void RaiseEventsOnClient(IntPtr hwnd, int eventId, object idProp, int idObject, int idChild)
{
ProxySimple el = null;
WindowsListBox wlb = (WindowsListBox)WindowsListBox.Create(hwnd, 0);
// Upon creation, a single selection Listbox can have no selection to start with
// however once an item has been selection, the selection cannot be removed.
// This WinEvent can only be received once, on the first selection.
// Once the notification is received the notification handler is removed to not get it a
// second time.
if ((eventId == NativeMethods.EventObjectSelection || eventId == NativeMethods.EventObjectSelectionAdd) && (idProp as AutomationProperty) == SelectionPattern.IsSelectionRequiredProperty)
{
// This array must be kept in sync with the array in PropertyToWinEvent
WinEventTracker.EvtIdProperty[] aEvtIdProperties = new WinEventTracker.EvtIdProperty[] { new WinEventTracker.EvtIdProperty(NativeMethods.EventObjectSelection, SelectionPattern.IsSelectionRequiredProperty) };
WinEventTracker.RemoveToNotificationList(hwnd, aEvtIdProperties, null, aEvtIdProperties.Length);
el = wlb;
}
else if (eventId == NativeMethods.EventObjectSelection || eventId == NativeMethods.EventObjectSelectionRemove || eventId == NativeMethods.EventObjectSelectionAdd)
{
bool isMultipleSelection = wlb.IsMultipleSelection();
// User should send SelectionAdd for a Multiselect listbox but it sends instead
// Selection. The code below fixes the
if (eventId == NativeMethods.EventObjectSelection && isMultipleSelection && wlb.HasOtherSelections(idChild - 1))
{
eventId = NativeMethods.EventObjectSelectionAdd;
}
// The spec says a ElementSelectionEvent should be fired when action causes only one
// selection.
if ((eventId == NativeMethods.EventObjectSelectionRemove || eventId == NativeMethods.EventObjectSelectionAdd) &&
isMultipleSelection && wlb.GetSelectionCount() == 1)
{
// The net result of the user action is that there is only one item selected in the
// listbox, so change the event to an EventObjectSelected.
idProp = SelectionItemPattern.ElementSelectedEvent;
eventId = NativeMethods.EventObjectSelection;
// Now need to find what item is selected.
int selection = wlb.GetOtherSelection(idChild - 1);
if (selection != NativeMethods.LB_ERR)
{
idChild = selection;
}
}
el = wlb.CreateListboxItem(idChild - 1);
}
else
{
el = wlb;
}
// Special case for logical element change for listbox item
if ((idProp as AutomationEvent) == AutomationElement.StructureChangedEvent &&
(eventId == NativeMethods.EventObjectDestroy || eventId == NativeMethods.EventObjectCreate))
{
// Since children are referenced by position in the tree, addition and removal
// of items leads to different results when asking properties for the same element
// On removal, item + 1 is now item!
// Use Children Invalidated to let the client knows that all the cached
AutomationInteropProvider.RaiseStructureChangedEvent(wlb, new StructureChangedEventArgs(StructureChangeType.ChildrenInvalidated, wlb.MakeRuntimeId()));
return;
}
if (el != null)
{
el.DispatchEvents(eventId, idProp, idObject, idChild);
}
}
// ------------------------------------------------------
//
// Constructors
//
// ------------------------------------------------------
#region Constructors
internal WinEventItem (ref WinEventTracker.EventHookParams hp, WinEventTracker.StartStopDelegate ssd)
{
_hp = hp;
_ssd = ssd;
}
// Return an array that contains combo's edit portion specific events
// These events will be remapped as combo box events
private static void CreateEditPortionEvents (out WinEventTracker.EvtIdProperty [] editPortionEvents, out int counter, AutomationProperty [] aidProps)
{
// count how many events to pass back for the edit part of combo
int c = 0;
foreach ( AutomationProperty p in aidProps )
{
if ( p == ValuePattern.ValueProperty || p == ValuePattern.IsReadOnlyProperty )
{
c++;
}
}
if (c == 0)
{
editPortionEvents = null;
counter = 0;
return;
}
// allocate array with the number of events from above
editPortionEvents = new WinEventTracker.EvtIdProperty[c];
c = 0;
foreach ( AutomationProperty p in aidProps )
{
if ( p == ValuePattern.ValueProperty || p == ValuePattern.IsReadOnlyProperty )
{
editPortionEvents[c]._idProp = p;
editPortionEvents[c]._evtId = (p == ValuePattern.ValueProperty) ? NativeMethods.EventObjectValueChange : NativeMethods.EventObjectStateChange;
c++;
}
}
counter = c;
}