private void ChangeFocus(DependencyObject focus, int timestamp)
{
DependencyObject o = null;
if (focus != _focus)
{
// Update the critical pieces of data.
DependencyObject oldFocus = _focus;
_focus = focus;
_focusRootVisual = InputElement.GetRootVisual(focus);
using (Dispatcher.DisableProcessing()) // Disable reentrancy due to locks taken
{
// Adjust the handlers we use to track everything.
if (oldFocus != null)
{
o = oldFocus;
if (InputElement.IsUIElement(o))
{
((UIElement)o).IsEnabledChanged -= _isEnabledChangedEventHandler;
((UIElement)o).IsVisibleChanged -= _isVisibleChangedEventHandler;
((UIElement)o).FocusableChanged -= _focusableChangedEventHandler;
}
else if (InputElement.IsContentElement(o))
{
((ContentElement)o).IsEnabledChanged -= _isEnabledChangedEventHandler;
// NOTE: there is no IsVisible property for ContentElements.
((ContentElement)o).FocusableChanged -= _focusableChangedEventHandler;
}
else
{
((UIElement3D)o).IsEnabledChanged -= _isEnabledChangedEventHandler;
((UIElement3D)o).IsVisibleChanged -= _isVisibleChangedEventHandler;
((UIElement3D)o).FocusableChanged -= _focusableChangedEventHandler;
}
}
if (_focus != null)
{
o = _focus;
if (InputElement.IsUIElement(o))
{
((UIElement)o).IsEnabledChanged += _isEnabledChangedEventHandler;
((UIElement)o).IsVisibleChanged += _isVisibleChangedEventHandler;
((UIElement)o).FocusableChanged += _focusableChangedEventHandler;
}
else if (InputElement.IsContentElement(o))
{
((ContentElement)o).IsEnabledChanged += _isEnabledChangedEventHandler;
// NOTE: there is no IsVisible property for ContentElements.
((ContentElement)o).FocusableChanged += _focusableChangedEventHandler;
}
else
{
((UIElement3D)o).IsEnabledChanged += _isEnabledChangedEventHandler;
((UIElement3D)o).IsVisibleChanged += _isVisibleChangedEventHandler;
((UIElement3D)o).FocusableChanged += _focusableChangedEventHandler;
}
}
}
// Oddly enough, update the FocusWithinProperty properties first. This is
// so any callbacks will see the more-common FocusWithinProperty properties
// set correctly.
UIElement.FocusWithinProperty.OnOriginValueChanged(oldFocus, _focus, ref _focusTreeState);
// Invalidate the IsKeyboardFocused properties.
if (oldFocus != null)
{
o = oldFocus;
o.SetValue(UIElement.IsKeyboardFocusedPropertyKey, false); // Same property for ContentElements
}
if (_focus != null)
{
// Invalidate the IsKeyboardFocused property.
o = _focus;
o.SetValue(UIElement.IsKeyboardFocusedPropertyKey, true); // Same property for ContentElements
}
// Call TestServicesManager change the focus of the InputMethod is enable/disabled accordingly
// so it's ready befere the GotKeyboardFocusEvent handler is invoked.
if (_TsfManager != null)
{
_TsfManager.Value.Focus(_focus);
}
// InputLanguageManager checks the preferred input languages.
// This should before GotEvent because the preferred input language
// should be set at the event handler.
InputLanguageManager.Current.Focus(_focus, oldFocus);
// Send the LostKeyboardFocus and GotKeyboardFocus events.
if (oldFocus != null)
{
KeyboardFocusChangedEventArgs lostFocus = new KeyboardFocusChangedEventArgs(this, timestamp, (IInputElement)oldFocus, (IInputElement)focus);
lostFocus.RoutedEvent = Keyboard.LostKeyboardFocusEvent;
lostFocus.Source = oldFocus;
if (_inputManager != null)
{
_inputManager.Value.ProcessInput(lostFocus);
}
}
if (_focus != null)
{
KeyboardFocusChangedEventArgs gotFocus = new KeyboardFocusChangedEventArgs(this, timestamp, (IInputElement)oldFocus, (IInputElement)_focus);
gotFocus.RoutedEvent = Keyboard.GotKeyboardFocusEvent;
gotFocus.Source = _focus;
if (_inputManager != null)
{
_inputManager.Value.ProcessInput(gotFocus);
}
}
// InputMethod checks the preferred ime state.
// The preferred input methods should be applied after Cicero TIP gots SetFocus callback.
InputMethod.Current.GotKeyboardFocus(_focus);
//Could be also built-in into IsKeyboardFocused_Changed static on UIElement and ContentElement
//However the Automation likes to go immediately back on us so it would be better be last one...
AutomationPeer.RaiseFocusChangedEventHelper((IInputElement)_focus);
}
}