/// <summary>
/// Will update the <see cref="CurrentItem"/> property. This method will be called when the
/// current item might have changed.
/// </summary>
protected void UpdateCurrentItem()
{
Screen screen = Screen;
FrameworkElement focusedElement = screen == null ? null : screen.FocusedElement;
if (_lastFocusedElement == focusedElement)
{
return;
}
_lastFocusedElement = focusedElement;
object lastCurrentItem = CurrentItem;
object newCurrentItem = null;
if (_itemsHostPanel != null && CheckFocusInScope(focusedElement))
{
Visual element = focusedElement;
while (element != null && element.VisualParent != _itemsHostPanel)
{
element = element.VisualParent;
}
newCurrentItem = element == null ? null : element.Context;
ISelectableItemContainer container = element as ISelectableItemContainer;
if (container != null)
{
container.Selected = true; // Triggers an update of our _lastSelectedItem
}
}
if (newCurrentItem != lastCurrentItem)
{
CurrentItem = newCurrentItem;
FireSelectionChanged(newCurrentItem);
}
}
public override void DeepCopy(IDeepCopyable source, ICopyManager copyManager)
{
_preventItemsPreparation = true;
Detach();
base.DeepCopy(source, copyManager);
ItemsControl c = (ItemsControl)source;
ItemsSource = copyManager.GetCopy(c.ItemsSource);
_items.Clear();
foreach (object item in c.Items)
{
_items.Add(copyManager.GetCopy(item));
}
ItemContainerStyle = copyManager.GetCopy(c.ItemContainerStyle);
ItemTemplate = copyManager.GetCopy(c.ItemTemplate);
GroupHeaderContainerStyle = copyManager.GetCopy(c.GroupHeaderContainerStyle);
GroupHeaderTemplate = copyManager.GetCopy(c.GroupHeaderTemplate);
ItemsPanel = copyManager.GetCopy(c.ItemsPanel);
DataStringProvider = copyManager.GetCopy(c.DataStringProvider);
RestoreFocus = c.RestoreFocus;
_lastSelectedItem = copyManager.GetCopy(c._lastSelectedItem);
Attach();
_preventItemsPreparation = false;
copyManager.CopyCompleted += manager => PrepareItems(false); // During the deep copy process, our referenced objects are not initialized yet so defer preparation of items to the end of the copy process
}
public void UpdateSelectedItem(ISelectableItemContainer container)
{
bool isSelected = container != null && container.Selected;
if (ReferenceEquals(_lastSelectedItem, container))
{ // Our selected container
if (!isSelected)
{
_lastSelectedItem = null;
}
return;
}
// Not our selected container
if (!isSelected)
{
return;
}
if (_lastSelectedItem != null)
{
_lastSelectedItem.Selected = false;
}
_lastSelectedItem = container;
}
protected void UpdatePreparedItems()
{
bool doSetItems;
bool doSetChildren;
ItemCollection preparedItems;
ItemCollection preparedChildren;
lock (_renderLock)
{
if (!_setItems && !_setChildren)
return;
doSetItems = _setItems;
_setItems = false;
doSetChildren = _setChildren;
_setChildren = false;
preparedItems = _preparedItems;
_preparedItems = null;
preparedChildren = _preparedChildren;
_preparedChildren = null;
}
Panel itemsHostPanel = _itemsHostPanel;
if (doSetChildren)
{
FrameworkElementCollection children = itemsHostPanel.Children;
lock (children.SyncRoot)
{
children.Clear(false);
if (preparedChildren != null)
{
IList<FrameworkElement> tempItems = new List<FrameworkElement>(preparedChildren.Count);
foreach (object item in preparedChildren.ExtractElements())
{
FrameworkElement fe = item as FrameworkElement;
if (fe == null)
{
MPF.TryCleanupAndDispose(item);
continue;
}
ISelectableItemContainer sic = item as ISelectableItemContainer;
if (sic != null && sic.Selected)
_lastSelectedItem = sic;
tempItems.Add(fe);
}
children.AddAll(tempItems);
preparedChildren.Dispose();
}
}
}
if (doSetItems)
{
_items.Clear();
if (preparedItems != null)
{
_items.AddAll(preparedItems.ExtractElements());
preparedItems.Dispose();
}
}
VirtualizingStackPanel vsp = itemsHostPanel as VirtualizingStackPanel;
if (vsp == null)
IsEmpty = itemsHostPanel.Children.Count == 0;
// else IsEmpty has been updated by PrepareItemsOverride
}
public void UpdateSelectedItem(ISelectableItemContainer container)
{
bool isSelected = container != null && container.Selected;
if (ReferenceEquals(_lastSelectedItem, container))
{ // Our selected container
if (!isSelected)
_lastSelectedItem = null;
return;
}
// Not our selected container
if (!isSelected)
return;
if (_lastSelectedItem != null)
_lastSelectedItem.Selected = false;
_lastSelectedItem = container;
}
public override void DeepCopy(IDeepCopyable source, ICopyManager copyManager)
{
_preventItemsPreparation = true;
Detach();
base.DeepCopy(source, copyManager);
ItemsControl c = (ItemsControl) source;
ItemsSource = copyManager.GetCopy(c.ItemsSource);
_items.Clear();
foreach (object item in c.Items)
_items.Add(copyManager.GetCopy(item));
ItemContainerStyle = copyManager.GetCopy(c.ItemContainerStyle);
SelectionChanged = copyManager.GetCopy(c.SelectionChanged);
ItemTemplate = copyManager.GetCopy(c.ItemTemplate);
ItemsPanel = copyManager.GetCopy(c.ItemsPanel);
DataStringProvider = copyManager.GetCopy(c.DataStringProvider);
_lastSelectedItem = copyManager.GetCopy(c._lastSelectedItem);
Attach();
_preventItemsPreparation = false;
copyManager.CopyCompleted += manager => PrepareItems(false); // During the deep copy process, our referenced objects are not initialized yet so defer preparation of items to the end of the copy process
}
protected void UpdatePreparedItems()
{
bool doSetItems;
bool doSetChildren;
ItemCollection preparedItems;
ItemCollection preparedChildren;
lock (_renderLock)
{
if (!_setItems && !_setChildren)
{
return;
}
doSetItems = _setItems;
_setItems = false;
doSetChildren = _setChildren;
_setChildren = false;
preparedItems = _preparedItems;
_preparedItems = null;
preparedChildren = _preparedChildren;
_preparedChildren = null;
}
Panel itemsHostPanel = _itemsHostPanel;
if (doSetChildren)
{
FrameworkElementCollection children = itemsHostPanel.Children;
lock (children.SyncRoot)
{
children.Clear(false);
if (preparedChildren != null)
{
IList <FrameworkElement> tempItems = new List <FrameworkElement>(preparedChildren.Count);
foreach (object item in preparedChildren.ExtractElements())
{
FrameworkElement fe = item as FrameworkElement;
if (fe == null)
{
MPF.TryCleanupAndDispose(item);
continue;
}
ISelectableItemContainer sic = item as ISelectableItemContainer;
if (sic != null && sic.Selected)
{
_lastSelectedItem = sic;
}
tempItems.Add(fe);
}
children.AddAll(tempItems);
preparedChildren.Dispose();
}
}
}
if (doSetItems)
{
_items.Clear();
if (preparedItems != null)
{
_items.AddAll(preparedItems.ExtractElements());
preparedItems.Dispose();
}
}
VirtualizingStackPanel vsp = itemsHostPanel as VirtualizingStackPanel;
IItemProvider itemProvider = vsp == null ? null : vsp.ItemProvider;
IsEmpty = (itemProvider == null ? itemsHostPanel.Children.Count : itemProvider.NumItems) == 0;
}
