| public ItemFromContainer ( DependencyObject container ) : object | ||
| container | DependencyObject | |
| return | object | |
private TabItem GetSelectedTabItem()
{
object selectedItem = SelectedItem;
if (selectedItem != null)
{
// Check if the selected item is a TabItem
TabItem tabItem = selectedItem as TabItem;
if (tabItem == null)
{
// It is a data item, get its TabItem container
tabItem = ItemContainerGenerator.ContainerFromIndex(SelectedIndex) as TabItem;
// Due to event leapfrogging, we may have the wrong container.
// If so, re-fetch the right container using a more expensive method.
// (BTW, the previous line will cause a debug assert in this case) [Dev10 452711]
if (tabItem == null ||
!ItemsControl.EqualsEx(selectedItem, ItemContainerGenerator.ItemFromContainer(tabItem)))
{
tabItem = ItemContainerGenerator.ContainerFromItem(selectedItem) as TabItem;
}
}
return(tabItem);
}
return(null);
}
private void SetSingleSelection(ListBoxItem item)
{
SelectedItem = ItemContainerGenerator.ItemFromContainer(item);
for (int i = 0; i < ItemContainerGenerator.ItemsCount; i++)
{
DependencyObject itemContainer = ItemContainerGenerator.Generate(i);
itemContainer.SetCurrentValue(Selector.IsSelectedProperty, itemContainer == item);
}
}
private void ToggleSingleSelection(ListBoxItem item)
{
bool isSelected = !(bool)item.GetValue(Selector.IsSelectedProperty);
SelectedItem = isSelected ? ItemContainerGenerator.ItemFromContainer(item) : null;
for (int i = 0; i < ItemContainerGenerator.ItemsCount; i++)
{
DependencyObject itemContainer = ItemContainerGenerator.Generate(i);
itemContainer.SetCurrentValue(Selector.IsSelectedProperty, itemContainer == item && isSelected);
}
}
public int IndexFromContainer(UIElement container)
{
if (container == null)
{
throw new ArgumentNullException("container");
}
ItemContainerGenerator itemContainerGenerator = base.ItemContainerGenerator as ItemContainerGenerator;
if (itemContainerGenerator != null && itemContainerGenerator.ItemFromContainer(container) != DependencyProperty.UnsetValue)
{
object obj = container.ReadLocalValue(IndexForItemContainerProperty);
return((obj as int?) ?? (-1));
}
return(-1);
}
/// <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);
}
public object ItemFromContainer(UIElement container)
{
if (container == null)
{
throw new ArgumentNullException("container");
}
ItemContainerGenerator itemContainerGenerator = base.ItemContainerGenerator as ItemContainerGenerator;
if (itemContainerGenerator != null)
{
object obj = itemContainerGenerator.ItemFromContainer(container);
if (obj == DependencyProperty.UnsetValue)
{
return(null);
}
return(obj);
}
return(null);
}
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;
}
}
}
