internal override void OnMouseDown(MouseButtonEventArgs e)
{
base.OnMouseDown(e);
_ItemForDeferredSelection = null;
TreeViewExItem item = GetTreeViewItemUnderMouse(e.GetPosition(treeViewEx));
if (item == null)
{
return;
}
if (e.ChangedButton != MouseButton.Left && !(e.ChangedButton == MouseButton.Right && item.ContextMenu != null))
{
return;
}
if (item.IsEditing)
{
return;
}
// Do not select on MouseDown if part of the selection list
// To enable drag'n'drop, this selction is done in MouseUp
if (treeViewEx.SelectedItems.Count > 1 && item.IsSelected)
{
_ItemForDeferredSelection = item;
return;
}
SelectSingleItem(item);
PresentationHelper.ForceFocus(item);
}
internal override void OnMouseUp(MouseButtonEventArgs e)
{
base.OnMouseUp(e);
TreeViewExItem item = GetTreeViewItemUnderMouse(e.GetPosition(treeViewEx));
if (item == null)
{
return;
}
if (e.ChangedButton != MouseButton.Left && !(e.ChangedButton == MouseButton.Right && item.ContextMenu != null))
{
return;
}
if (item.IsEditing)
{
return;
}
// To enable drag'n'drop, this selection is done in MouseUp
if (ReferenceEquals(_ItemForDeferredSelection, item))
{
SelectSingleItem(item);
_ItemForDeferredSelection = null;
}
}
void OnDrop(object sender, DragEventArgs e)
{
e.Handled = true;
TreeViewExItem item = GetTreeViewItemUnderMouse(e.GetPosition(TreeView));
//if (item == null)
//{
// CleanUpAdorners();
// return;
//}
CanInsertReturn canInsertReturn = CanInsert(item, e.GetPosition, e.Data);
if (canInsertReturn != null)
{
// insert and return
TreeView.DropCommand.Execute(new DropParameters(item.ParentTreeViewItem, e.Data, canInsertReturn.Index));
CleanUpAdorners();
return;
}
// check if drop is possible
if (CanDrop(item, e.Data))
{
// drop and return
TreeView.DropCommand.Execute(new DropParameters(item, e.Data));
}
DragEnd();
}
public void BringIntoView(object item)
{
UpdateLayout();
TreeViewExItem tvei = GetTreeViewItemFor(item);
tvei?.BringIntoView();
}
public void SelectCurrentBySpace()
{
TreeViewExItem item = GetFocusedItem();
SelectSingleItem(item);
PresentationHelper.ForceFocus(item);
}
protected override void OnKeyUp(KeyEventArgs e)
{
base.OnKeyUp(e);
if (!e.Handled)
{
Key key = e.Key;
switch (key)
{
case Key.Left:
case Key.Right:
case Key.Up:
case Key.Down:
case Key.Add:
case Key.Subtract:
case Key.Space:
IEnumerable <TreeViewExItem> items = TreeViewElementFinder.FindAll(ParentTreeView, false);
TreeViewExItem focusedItem = items.FirstOrDefault(x => x.IsFocused);
if (focusedItem != null)
{
focusedItem.BringIntoView(new Rect(1, 1, 1, 1));
}
break;
}
}
}
private void SelectWithShift(TreeViewExItem item)
{
object firstSelectedItem;
if (lastShiftRoot != null)
{
firstSelectedItem = lastShiftRoot;
}
else
{
if (treeViewEx.SelectedItems.Count > 0)
{
firstSelectedItem = treeViewEx.SelectedItems[0];
}
else
{
firstSelectedItem = null;
}
}
TreeViewExItem shiftRootItem = treeViewEx.GetTreeViewItemsFor(new List <object> {
firstSelectedItem
}).First();
List <object> itemsToSelect = treeViewEx.GetNodesToSelectBetween(shiftRootItem, item).Select(x => x.DataContext).ToList();
List <object> itemsToUnSelect = ((IEnumerable <object>)treeViewEx.SelectedItems).ToList();
ModifySelection(itemsToSelect, itemsToUnSelect);
}
public DropParameters(TreeViewExItem dropToItem, IDataObject dropData, int index)
{
this.DropToItem = dropToItem;
this.DropData = dropData;
this.InsertAtIndex = index;
_Content = dropData.GetData(typeof(DragContent)) as DragContent;
}
private TreeViewExItem GetVisible(TreeViewExItem treeViewExItem)
{
if (treeViewExItem.IsVisible)
{
return(treeViewExItem);
}
return(null);
}
bool CanDrop(TreeViewExItem item, IDataObject data)
{
if (TreeView.DropCommand == null)
{
return(false);
}
return(TreeView.DropCommand.CanExecute(new DropParameters(item, data)));
}
private int GetHierarchyLevel()
{
TreeViewExItem treeViewItem = ItemsControl.GetItemsOwner(this) as TreeViewExItem;
if (treeViewItem == null)
{
return(0);
}
return(treeViewItem.hierachyLevel);
}
private static void InvalidateMeasure(TreeViewExItem child)
{
var itemsPresenter = child.Template.FindName("itemsPresenter", child) as FrameworkElement;
if (itemsPresenter != null)
{
var virtualizingTreePanel = VisualTreeHelper.GetChild(itemsPresenter, 0) as UIElement;
virtualizingTreePanel.InvalidateMeasure();
}
}
private void AddOrInsertItemToInternalChildren(int itemGeneratorIndex, TreeViewExItem child)
{
if (itemGeneratorIndex >= InternalChildren.Count)
{
base.AddInternalChild(child);
}
else
{
base.InsertInternalChild(itemGeneratorIndex, child);
}
}
public void SelectLast()
{
TreeViewExItem item = TreeViewElementFinder.FindLast(treeViewEx, true);
if (item != null)
{
SelectSingleItem(item);
}
PresentationHelper.ForceFocus(item);
}
private void ToggleItem(TreeViewExItem item)
{
if (treeViewEx.SelectedItems.Contains(item.DataContext))
{
ModifySelection(null, item.DataContext);
}
else
{
ModifySelection(item.DataContext, null);
}
}
CanInsertReturn CanInsert(TreeViewExItem item, Func <UIElement, Point> getPositionDelegate, IDataObject data)
{
if (TreeView.DropCommand == null)
{
return(null);
}
if (item == null)
{
return(null);
}
else
{
// get position over element
Size size = item.RenderSize;
Point positionRelativeToItem = getPositionDelegate(item);
// decide whether to insert before or after item
bool after = true;
if (positionRelativeToItem.Y > DragAreaSize)
{
if (size.Height - positionRelativeToItem.Y > DragAreaSize)
{
return(null);
}
}
else
{
after = false;
}
// get index, where to insert
TreeViewExItem parentItem = item.ParentTreeViewItem;
ItemContainerGenerator itemContainerGenerator = (parentItem != null)?parentItem.ItemContainerGenerator:TreeView.ItemContainerGenerator;
int index = itemContainerGenerator.IndexFromContainer(item);
if (after)
{
// dont allow insertion after item, if item has children
if (item.HasItems)
{
return(null);
}
index++;
}
// ask if insertion is allowed
if (TreeView.DropCommand.CanExecute(new DropParameters(parentItem, data, index)))
{
return(new CanInsertReturn("", index, !after));
}
}
return(null);
}
private static TreeViewExItem GetFirstVirtualizedItem(TreeViewExItem treeViewItem)
{
for (int i = 0; i < treeViewItem.Items.Count; i++)
{
TreeViewExItem item = treeViewItem.ItemContainerGenerator.ContainerFromIndex(i) as TreeViewExItem;
if (item != null)
{
return(item);
}
}
return(null);
}
/// <summary>
/// Returns all items in tree recursively. If virtualization is enabled, only realized items are returned.
/// </summary>
/// <param name="treeView">The tree.</param>
/// <param name="visibleOnly">True if only visible items should be returned.</param>
/// <returns>Returns an enumerable of items.</returns>
internal static IEnumerable <TreeViewExItem> FindAll(TreeViewEx treeView, bool visibleOnly)
{
TreeViewExItem currentItem = FindFirst(treeView, visibleOnly);
while (currentItem != null)
{
if (!visibleOnly || currentItem.IsVisible)
{
yield return(currentItem);
}
currentItem = FindNext(currentItem, visibleOnly);
}
}
internal bool StopEditing()
{
if (_EditedItem == null)
{
return(false);
}
Keyboard.Focus(_EditedItem);
_EditedItem.IsEditing = false;
PresentationHelper.ForceFocus(_EditedItem);
_EditedItem = null;
return(true);
}
internal TreeViewExItem GetNextItem(TreeViewExItem item, List <TreeViewExItem> items)
{
int indexOfCurrent = items.IndexOf(item);
for (int i = indexOfCurrent + 1; i < items.Count; i++)
{
if (items[i].IsVisible)
{
return(items[i]);
}
}
return(null);
}
internal IEnumerable <TreeViewExItem> GetNodesToSelectBetween(TreeViewExItem firstNode, TreeViewExItem lastNode)
{
var allNodes = TreeViewElementFinder.FindAll(this, false).ToList();
var firstIndex = allNodes.IndexOf(firstNode);
var lastIndex = allNodes.IndexOf(lastNode);
if (firstIndex >= allNodes.Count)
{
throw new InvalidOperationException(
"First node index " + firstIndex + "greater or equal than count " + allNodes.Count + ".");
}
if (lastIndex >= allNodes.Count)
{
throw new InvalidOperationException(
"Last node index " + lastIndex + " greater or equal than count " + allNodes.Count + ".");
}
var nodesToSelect = new List <TreeViewExItem>();
if (lastIndex == firstIndex)
{
return(new List <TreeViewExItem> {
firstNode
});
}
if (lastIndex > firstIndex)
{
for (int i = firstIndex; i <= lastIndex; i++)
{
if (allNodes[i].IsVisible)
{
nodesToSelect.Add(allNodes[i]);
}
}
}
else
{
for (int i = firstIndex; i >= lastIndex; i--)
{
if (allNodes[i].IsVisible)
{
nodesToSelect.Add(allNodes[i]);
}
}
}
return(nodesToSelect);
}
internal TreeViewExItem GetPreviousItem(TreeViewExItem item, List <TreeViewExItem> items)
{
int indexOfCurrent = items.IndexOf(item);
for (int i = indexOfCurrent - 1; i >= 0; i--)
{
if (items[i].IsVisible)
{
return(items[i]);
}
}
return(null);
}
internal IEnumerable <TreeViewExItem> GetChildren(TreeViewExItem item)
{
if (item == null)
{
yield break;
}
for (int i = 0; i < item.Items.Count; i++)
{
TreeViewExItem child = item.ItemContainerGenerator.ContainerFromIndex(i) as TreeViewExItem;
if (child != null)
{
yield return(child);
}
}
}
public void Dispose()
{
if (TreeView != null)
{
TreeView.Drop -= OnDrop;
TreeView.DragOver -= OnDragOver;
TreeView.DragLeave -= OnDragLeave;
}
if (_ItemMouseIsOver != null)
{
_ItemMouseIsOver.IsCurrentDropTarget = false;
_ItemMouseIsOver = null;
}
}
public void SelectFromProperty(TreeViewExItem item, bool isSelected)
{
// we do not check if selection is allowed, because selecting on that way is no user action.
// Hopefully the programmer knows what he does...
if (isSelected)
{
treeViewEx.SelectedItems.Add(item.DataContext);
lastShiftRoot = item.DataContext;
//FocusHelper.Focus(item);
}
else
{
treeViewEx.SelectedItems.Remove(item.DataContext);
}
}
protected override List <AutomationPeer> GetChildrenCore()
{
List <AutomationPeer> children = new List <AutomationPeer>();
for (int i = 0; i < treeViewExItem.Items.Count; i++)
{
TreeViewExItem child = treeViewExItem.ItemContainerGenerator.ContainerFromIndex(i) as TreeViewExItem;
if (child == null)
{
continue;
}
children.Add(new TreeViewExItemAutomationPeer(child, treeViewExAutomationPeer));
}
return(children);
}
List <TreeViewExItem> GetDraggableItems(Point mousePositionRelativeToTree)
{
if (TreeView.DragCommand == null)
{
return(new List <TreeViewExItem>());
}
List <TreeViewExItem> items = TreeView.GetTreeViewItemsFor(TreeView.SelectedItems).ToList();
TreeViewExItem itemUnderMouse = GetTreeViewItemUnderMouse(mousePositionRelativeToTree);
if (itemUnderMouse == null)
{
return(new List <TreeViewExItem>());
}
if (items.Contains(itemUnderMouse))
{
foreach (var item in items)
{
if (!TreeView.DragCommand.CanExecute(new DragParameters(item)))
{
// if one item is not draggable, nothing can be dragged
return(new List <TreeViewExItem>());
}
}
return(items);
}
//mouse is not over an selected item. We have to check if it is over the content. In this case we have to select and start drag n drop.
var contentPresenter = itemUnderMouse.Template.FindName("content", itemUnderMouse) as ContentPresenter;
if (contentPresenter.IsMouseOver)
{
if (TreeView.DragCommand.CanExecute(new DragParameters(itemUnderMouse)))
{
return new List <TreeViewExItem> {
itemUnderMouse
}
}
;
}
return(new List <TreeViewExItem>());
}
public Rect MakeVisible(Visual visual, Rect rectangle)
{
if (rectangle.IsEmpty || visual == null || visual == this || !base.IsAncestorOf(visual))
{
return(Rect.Empty);
}
TreeViewExItem treeViewExItem = visual as TreeViewExItem;
FrameworkElement element;
if (treeViewExItem != null)
{
element = treeViewExItem.Template.FindName("border", treeViewExItem) as FrameworkElement;
}
else
{
element = visual as FrameworkElement;
}
var transform = visual.TransformToAncestor(this);
Point p = transform.Transform(new Point(0, 0));
Rect rect = new Rect(p, element.RenderSize);
if (rect.X < 0)
{
SetHorizontalOffset(HorizontalOffset + rect.X);
}
else if (treeViewExItem != null && treeViewExItem.ParentTreeView.ActualWidth < rect.X)
{
SetHorizontalOffset(HorizontalOffset + rect.X);
}
if (rect.Y < 0)
{
SetVerticalOffset(VerticalOffset + rect.Y);
}
else if (treeViewExItem != null && treeViewExItem.ParentTreeView.ActualHeight < rect.Y + rect.Height)
{
// set 5 more, so the next item is realized for sure.
double verticalOffset = rect.Y + rect.Height + VerticalOffset - treeViewExItem.ParentTreeView.ActualHeight + 5;
SetVerticalOffset(verticalOffset);
}
return(new Rect(HorizontalOffset, VerticalOffset, ViewportWidth, ViewportHeight));
}
public void SelectNextFromKey()
{
TreeViewExItem item = GetFocusedItem();
item = TreeViewElementFinder.FindNext(item, true);
if (item == null)
{
return;
}
// if ctrl is pressed just focus it, so it can be selected by space. Otherwise select it.
if (!IsControlKeyDown)
{
SelectSingleItem(item);
}
PresentationHelper.ForceFocus(item);
}
public void SelectPreviousFromKey()
{
List <TreeViewExItem> items = TreeViewElementFinder.FindAll(treeViewEx, true).ToList();
TreeViewExItem item = GetFocusedItem();
item = treeViewEx.GetPreviousItem(item, items);
if (item == null)
{
return;
}
// if ctrl is pressed just focus it, so it can be selected by space. Otherwise select it.
if (!IsControlKeyDown)
{
SelectSingleItem(item);
}
PresentationHelper.ForceFocus(item);
}