private void Update()
{
if (!SuspendUpdates && SomethingChanged)
{
if (ShowFolderHighlight)
{
_folderHighlight.Height = DragOverBehavior.GetDragOverVisualHeight(DragOverElement) + (LineThicknessScale * LineThickness);
_folderHighlight.Width = GetAdornerWidth();
_layoutRoot.Children.Remove(_itemHighlight);
if (!_layoutRoot.Children.Contains(_folderHighlight))
{
_layoutRoot.Children.Add(_folderHighlight);
}
}
else
{
_line.X2 = GetAdornerWidth();
_layoutRoot.Children.Remove(_folderHighlight);
if (!_layoutRoot.Children.Contains(_itemHighlight))
{
_layoutRoot.Children.Add(_itemHighlight);
}
}
InvalidateMeasure();
InvalidateArrange();
SomethingChanged = false;
}
}
private void InitializeShapes()
{
_layoutRoot.VerticalAlignment = VerticalAlignment.Center;
_layoutRoot.Background = null;
_layoutRoot.IsHitTestVisible = false;
var treeViewItem = DragOverElement as TreeListViewItem;
if (treeViewItem != null)
{
Indent = treeViewItem.Level * LevelToIndentConverter.IndentSize;
}
_line.HorizontalAlignment = HorizontalAlignment.Left;
_line.X1 = 0;
_line.Y1 = 0;
_line.X2 = GetAdornerWidth();
_line.Y2 = 0;
_line.StrokeThickness = LineThickness;
_line.Fill = SystemColors.ControlTextBrush;
_line.Stroke = SystemColors.ControlTextBrush;
var _leftArrow = new Polygon();
_leftArrow.Fill = SystemColors.ControlTextBrush;
_leftArrow.Stroke = SystemColors.ControlTextBrush;
_leftArrow.HorizontalAlignment = HorizontalAlignment.Left;
_leftArrow.Points = new PointCollection(new Point[] { new Point(0, -LineThicknessScale * LineThickness), new Point(0, LineThicknessScale * LineThickness), new Point(LineThicknessScale * LineThickness, 0) });
var _rightArrow = new Polygon();
_rightArrow.Fill = SystemColors.ControlTextBrush;
_rightArrow.Stroke = SystemColors.ControlTextBrush;
_rightArrow.HorizontalAlignment = HorizontalAlignment.Right;
_rightArrow.Points = new PointCollection(new Point[] { new Point(0, -LineThicknessScale * LineThickness), new Point(0, LineThicknessScale * LineThickness), new Point(-LineThicknessScale * LineThickness, 0) });
_itemHighlight.VerticalAlignment = VerticalAlignment.Center;
_itemHighlight.Children.Add(_line);
_itemHighlight.Children.Add(_leftArrow);
_itemHighlight.Children.Add(_rightArrow);
_folderHighlight.Width = GetAdornerWidth();
_folderHighlight.Height = DragOverBehavior.GetDragOverVisualHeight(DragOverElement) + (LineThicknessScale * LineThickness);
_folderHighlight.StrokeThickness = LineThickness;
_folderHighlight.Stroke = SystemColors.ControlTextBrush;
Update();
}
/// <inheritdoc />
protected override Size ArrangeOverride(Size finalSize)
{
if (_visualCollection != null)
{
var childLocation = DragOverElement.TranslatePoint(new Point(), AdornedElement);
var y = 0.0;
var offsetY = _layoutRoot.DesiredSize.Height / 2;
var adjustY = 3;
switch (DropLocation)
{
case DropOnItemLocation.TopQuarter:
y = childLocation.Y - offsetY + adjustY;
break;
case DropOnItemLocation.TopMiddleQuarter:
if (ShowFolderHighlight)
{
y = childLocation.Y - LineThickness;
}
else
{
y = childLocation.Y - offsetY + adjustY;
}
break;
case DropOnItemLocation.BottomMiddleQuarter:
if (ShowFolderHighlight)
{
y = childLocation.Y - LineThickness;
}
else
{
y = childLocation.Y + DragOverBehavior.GetDragOverVisualHeight(DragOverElement) - offsetY + adjustY;
}
break;
case DropOnItemLocation.BottomQuarter:
y = childLocation.Y + DragOverBehavior.GetDragOverVisualHeight(DragOverElement) - offsetY + adjustY;
break;
}
Rect elementRect = new Rect((2 * Inset) + Indent, y, _layoutRoot.DesiredSize.Width, _layoutRoot.DesiredSize.Height);
_layoutRoot.Arrange(elementRect);
}
return(finalSize);
}
