| public ContainerFromIndex ( int index ) : DependencyObject | ||
| index | int | |
| return | DependencyObject | |
/// <summary>
/// Returns a sequence of rating items.
/// </summary>
/// <returns>A sequence of rating items.</returns>
internal IEnumerable <RatingItem> GetRatingItems()
{
return
(Enumerable
.Range(0, this.Items.Count)
.Select(index => (RatingItem)ItemContainerGenerator.ContainerFromIndex(index))
.Where(ratingItem => ratingItem != null));
}
/// <summary>
/// Focus the first item in the TreeView.
/// </summary>
/// <returns>A value indicating whether the item was focused.</returns>
private bool FocusFirstItem()
{
// Get the first item in the TreeView.
TreeViewItem item = ItemContainerGenerator.ContainerFromIndex(0) as TreeViewItem;
return((item != null) ?
(item.IsEnabled && item.Focus()) || item.FocusDown() :
false);
}
internal virtual void OnItemTemplateChanged(DataTemplate oldValue, DataTemplate newValue)
{
int count = Items.Count;
for (int i = 0; i < count; i++)
{
UpdateContentTemplateOnContainer(ItemContainerGenerator.ContainerFromIndex(i), Items [i]);
}
}
public UIElement ContainerFromIndex(int itemIndex)
{
ItemContainerGenerator itemContainerGenerator = base.ItemContainerGenerator as ItemContainerGenerator;
if (itemContainerGenerator != null)
{
return(itemContainerGenerator.ContainerFromIndex(itemIndex) as UIElement);
}
return(null);
}
/// <summary>
/// Focus the last item in the TreeView.
/// </summary>
/// <returns>A value indicating whether the item was focused.</returns>
private bool FocusLastItem()
{
for (int i = Items.Count - 1; i >= 0; i--)
{
TreeViewItem item = ItemContainerGenerator.ContainerFromIndex(i) as TreeViewItem;
if (item != null && item.IsEnabled)
{
return(item.FocusInto());
}
}
return(false);
}
internal override void OnItemContainerStyleChanged(Style oldStyle, Style newStyle)
{
int count = Items.Count;
for (int i = 0; i < count; i++)
{
ListBoxItem item = (ListBoxItem)ItemContainerGenerator.ContainerFromIndex(i);
if (item != null && item.Style == oldStyle)
{
item.Style = newStyle;
}
}
}
void OnDisplayMemberPathChanged(string oldPath, string newPath)
{
// refresh the display member template.
displayMemberTemplate = null;
var newTemplate = DisplayMemberTemplate;
int count = Items.Count;
for (int i = 0; i < count; i++)
{
UpdateContentTemplateOnContainer(ItemContainerGenerator.ContainerFromIndex(i), Items [i]);
}
}
/// <summary>
/// Returns a sequence of rating items.
/// </summary>
/// <returns>A sequence of rating items.</returns>
internal IEnumerable <RatingItem> GetRatingItems()
{
#if SILVERLIGHT
return
(Enumerable
.Range(0, this.Items.Count)
.Select(index => (RatingItem)ItemContainerGenerator.ContainerFromIndex(index))
.Where(ratingItem => ratingItem != null));
#else
// The query above returns null in WPF
// Either way, WPF will already contain the RatingItem objects in the Items collection.
return(Items.Cast <RatingItem>());
#endif
}
internal override void OnItemContainerStyleChanged(Style oldStyle, Style newStyle)
{
int count = Items.Count;
for (int i = 0; i < count; i++)
{
var item = Items [i];
var container = (ListBoxItem)ItemContainerGenerator.ContainerFromIndex(i);
if (container != null && item != container)
{
container.Style = newStyle;
}
}
}
private bool GetFirstItem(out object item, out TreeViewItem container)
{
if (HasItems)
{
item = Items[0];
container = ItemContainerGenerator.ContainerFromIndex(0) as TreeViewItem;
return((item != null) && (container != null));
}
else
{
item = null;
container = null;
return(false);
}
}
/// <summary>
/// Select the first item of the TreeView.
/// </summary>
private void SelectFirstItem()
{
TreeViewItem container = ItemContainerGenerator.ContainerFromIndex(0) as TreeViewItem;
bool found = container != null;
if (!found)
{
container = SelectedContainer;
}
object item = found ?
ItemContainerGenerator.ItemFromContainer(container) :
SelectedItem;
ChangeSelection(item, container, found);
}
/// <summary>
/// Method which generates the focus trail cell
/// if it is not already generated and adds it to
/// the block lists appropriately.
/// </summary>
private bool GenerateChildForFocusTrail(
ItemContainerGenerator generator,
List<int> realizedColumnIndices,
List<int> realizedColumnDisplayIndices,
Size constraint,
int displayIndex,
ref int displayIndexListIterator)
{
DataGrid dataGrid = ParentDataGrid;
DataGridColumn column = dataGrid.ColumnFromDisplayIndex(displayIndex);
if (column.IsVisible)
{
int columnIndex = dataGrid.ColumnIndexFromDisplayIndex(displayIndex);
UIElement child = generator.ContainerFromIndex(columnIndex) as UIElement;
if (child == null)
{
int childIndex = columnIndex;
Size childSize;
using (((IItemContainerGenerator)generator).StartAt(IndexToGeneratorPositionForStart(generator, childIndex, out childIndex), GeneratorDirection.Forward, true))
{
child = GenerateChild(generator, constraint, column, ref childIndex, out childSize);
}
}
if (child != null && DataGridHelper.TreeHasFocusAndTabStop(child))
{
AddToIndicesListIfNeeded(
realizedColumnIndices,
realizedColumnDisplayIndices,
columnIndex,
displayIndex,
ref displayIndexListIterator);
return true;
}
}
return false;
}
// update container and index with current values
internal ItemInfo Refresh(ItemContainerGenerator generator)
{
if (Container == null && Index < 0)
{
Container = generator.ContainerFromItem(Item);
}
if (Index < 0 && Container != null)
{
Index = generator.IndexFromContainer(Container);
}
if (Container == null && Index >= 0)
{
Container = generator.ContainerFromIndex(Index);
}
if (Container == SentinelContainer && Index >= 0)
{
Container = null; // caller explicitly wants null container
}
return this;
}
protected override void OnKeyDown(KeyEventArgs e)
{
if (!e.Handled)
{
bool handled = false;
int newFocusedIndex = -1;
switch (e.Key)
{
case Key.Space:
case Key.Enter:
if ((Key.Enter != e.Key) || KeyboardNavigation.GetAcceptsReturn(this))
{
if (ModifierKeys.Alt != (Keyboard.Modifiers & (ModifierKeys.Control | ModifierKeys.Alt)))
{
// KeyEventArgs.OriginalSource (used by WPF) isn't available in Silverlight; use FocusManager.GetFocusedElement instead
ListBoxItem listBoxItem = FocusManager.GetFocusedElement() as ListBoxItem;
if (null != listBoxItem)
{
if ((ModifierKeys.Control == (Keyboard.Modifiers & ModifierKeys.Control)) && listBoxItem.IsSelected)
{
SelectedItem = null;
}
else
{
SelectedItem = ItemContainerGenerator.ItemFromContainer(listBoxItem);
}
handled = true;
}
}
}
break;
case Key.Home:
newFocusedIndex = 0;
break;
case Key.End:
newFocusedIndex = Items.Count - 1;
break;
case Key.PageUp:
newFocusedIndex = NavigateByPage(false);
break;
case Key.PageDown:
newFocusedIndex = NavigateByPage(true);
break;
case Key.Left:
if (IsVerticalOrientation())
{
ElementScrollViewerScrollInDirection(Key.Left);
}
else
{
newFocusedIndex = _focusedIndex - 1;
}
break;
case Key.Up:
if (IsVerticalOrientation())
{
newFocusedIndex = _focusedIndex - 1;
}
else
{
ElementScrollViewerScrollInDirection(Key.Up);
}
break;
case Key.Right:
if (IsVerticalOrientation())
{
ElementScrollViewerScrollInDirection(Key.Right);
}
else
{
newFocusedIndex = _focusedIndex + 1;
}
break;
case Key.Down:
if (IsVerticalOrientation())
{
newFocusedIndex = _focusedIndex + 1;
}
else
{
ElementScrollViewerScrollInDirection(Key.Down);
}
break;
// case Key.Divide: // Feature only used by SelectionMode.Extended
// case Key.Oem2: // Key not supported by Silverlight
// break;
// case Key.Oem5: // Key not supported by Silverlight
// break;
default:
Debug.Assert(!handled);
break;
}
if ((-1 != newFocusedIndex) &&
(-1 != _focusedIndex) &&
(newFocusedIndex != _focusedIndex) &&
(0 <= newFocusedIndex) &&
(newFocusedIndex < Items.Count))
{
// A key press will change the focused ListBoxItem
ListBoxItem listBoxItem = (ListBoxItem)ItemContainerGenerator.ContainerFromIndex(newFocusedIndex);
Debug.Assert(null != listBoxItem);
ScrollIntoView(ItemContainerGenerator.ItemFromContainer(listBoxItem));
if ((Keyboard.Modifiers & ModifierKeys.Control) == ModifierKeys.Control)
{
listBoxItem.Focus();
}
else
{
SelectedItem = ItemContainerGenerator.ItemFromContainer(listBoxItem);
}
handled = true;
}
if (handled)
{
e.Handled = true;
}
}
}
private ListBoxItem ElementAt(int index)
{
return(ItemContainerGenerator.ContainerFromIndex(index) as ListBoxItem);
}
/// <summary>
/// Treeview doesn't have a simple clear selection
/// </summary>
/// <remarks>
/// Got this here:
/// http://stackoverflow.com/questions/676819/wpf-treeview-clear-selection
/// </remarks>
private static void ClearTreeViewSelection(ItemCollection items, ItemContainerGenerator containerGenerator)
{
if (items != null && containerGenerator != null)
{
for (int cntr = 0; cntr < items.Count; cntr++)
{
// Can't use item directly, because it could be any UIElement
TreeViewItem itemContainer = containerGenerator.ContainerFromIndex(cntr) as TreeViewItem;
if (itemContainer != null)
{
// Recurse
ClearTreeViewSelection(itemContainer.Items, itemContainer.ItemContainerGenerator);
itemContainer.IsSelected = false;
}
}
}
}
void UpdateDisplayedItem(object selectedItem)
{
object content;
// Can't do anything with no content presenter
if (_contentPresenter == null)
{
return;
}
// Return the currently displayed object (which is a UIElement)
// to its original container.
if (DisplayedItem != null)
{
content = _contentPresenter.Content;
DisplayedItem.Content = content;
DisplayedItem = null;
}
_contentPresenter.Content = null;
if (selectedItem == null)
{
_contentPresenter.Content = NothingSelectedFallback;
_contentPresenter.ContentTemplate = null;
SelectionBoxItem = null;
SelectionBoxItemTemplate = null;
return;
}
// If the currently selected item is a ComboBoxItem (not ListBoxItem!), we
// display its Content instead of the CBI itself.
content = selectedItem;
if (content is ComboBoxItem)
{
content = ((ComboBoxItem)content).Content;
}
// Only allow DisplayedItem to be non-null if we physically move
// its content. This will only happen if DisplayedItem == SelectedItem
DisplayedItem = ItemContainerGenerator.ContainerFromIndex(SelectedIndex) as ComboBoxItem;
SelectionBoxItem = content;
SelectionBoxItemTemplate = ItemTemplate;
// If displayed item is avaiable, we can get the right template from there. Otherwise
// we need to create a container, read the template and destroy it.
if (DisplayedItem != null)
{
SelectionBoxItemTemplate = DisplayedItem.ContentTemplate;
if (content is UIElement)
{
DisplayedItem.Content = null;
}
else
{
DisplayedItem = null;
}
}
else
{
bool fresh;
ComboBoxItem container = ItemContainerGenerator.ContainerFromIndex(SelectedIndex) as ComboBoxItem;
if (container == null)
{
var index = ItemContainerGenerator.GeneratorPositionFromIndex(SelectedIndex);
using (ItemContainerGenerator.StartAt(index, GeneratorDirection.Forward, true))
container = ItemContainerGenerator.GenerateNext(out fresh) as ComboBoxItem;
ItemContainerGenerator.PrepareItemContainer(container);
}
SelectionBoxItemTemplate = container.ContentTemplate;
}
_contentPresenter.Content = SelectionBoxItem;
_contentPresenter.ContentTemplate = SelectionBoxItemTemplate;
}
protected override void OnKeyDown(KeyEventArgs e)
{
base.OnKeyDown(e);
if (!e.Handled)
{
var key = e.Key;
if (FlowDirection == FlowDirection.RightToLeft)
{
if (key == Key.Left)
{
key = Key.Right;
}
else if (key == Key.Right)
{
key = Key.Left;
}
}
e.Handled = true;
switch (key)
{
case Key.Escape:
IsDropDownOpen = false;
break;
case Key.Enter:
case Key.Space:
if (IsDropDownOpen && FocusedIndex != SelectedIndex)
{
SelectedIndex = FocusedIndex;
IsDropDownOpen = false;
}
else
{
IsDropDownOpen = true;
}
break;
case Key.Right:
case Key.Down:
if (IsDropDownOpen)
{
if (FocusedIndex < Items.Count - 1)
{
FocusedIndex++;
((Control)ItemContainerGenerator.ContainerFromIndex(FocusedIndex)).Focus();
}
}
else
{
SelectedIndex = Math.Min(SelectedIndex + 1, Items.Count - 1);
}
break;
case Key.Left:
case Key.Up:
if (IsDropDownOpen)
{
if (FocusedIndex > 0)
{
FocusedIndex--;
((Control)ItemContainerGenerator.ContainerFromIndex(FocusedIndex)).Focus();
}
}
else if (SelectedIndex != -1)
{
SelectedIndex = Math.Max(SelectedIndex - 1, 0);
}
break;
default:
e.Handled = false;
break;
}
}
else
{
Console.WriteLine("Already handled");
}
}
void IsDropDownOpenChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
{
bool open = (bool)e.NewValue;
if (_popup != null)
{
_popup.IsOpen = open;
}
if (_dropDownToggle != null)
{
_dropDownToggle.IsChecked = open;
}
if (open)
{
ComboBoxItem t = null;
FocusedIndex = Items.Count > 0 ? Math.Max(SelectedIndex, 0) : -1;
if (FocusedIndex > -1)
{
t = ItemContainerGenerator.ContainerFromIndex(FocusedIndex) as ComboBoxItem;
}
// If the ItemsPresenter hasn't attached yet 't' will be null.
// When the itemsPresenter attaches, focus will be set when the
// item is loaded
if (t != null)
{
t.Focus();
}
LayoutUpdated += UpdatePopupSizeAndPosition;
OnDropDownOpened(EventArgs.Empty);
// Raises UIA Event
AutomationPeer peer = ((ComboBox)sender).AutomationPeer;
if (peer != null)
{
peer.RaisePropertyChangedEvent(ExpandCollapsePatternIdentifiers.ExpandCollapseStateProperty,
ExpandCollapseState.Collapsed,
ExpandCollapseState.Expanded);
}
}
else
{
Focus();
LayoutUpdated -= UpdatePopupSizeAndPosition;
OnDropDownClosed(EventArgs.Empty);
// Raises UIA Event
AutomationPeer peer = ((ComboBox)sender).AutomationPeer;
if (peer != null)
{
peer.RaisePropertyChangedEvent(ExpandCollapsePatternIdentifiers.ExpandCollapseStateProperty,
ExpandCollapseState.Expanded,
ExpandCollapseState.Collapsed);
}
}
UpdateDisplayedItem(open && SelectedItem is UIElement ? null : SelectedItem);
UpdateVisualState(true);
}
