/// <summary>
/// 折叠起那些不是当前选择行或其父节点的所有行。
/// </summary>
private void ApplyAutoCollapse()
{
if (!this.AutoCollapse)
{
return;
}
object selected = this.SelectedItem;
var itemsControl = this.RootItemsControl;
if (selected == null)
{
//if we don't have a selected item, just collapse the
//root items
foreach (TreeGridRow node in TreeGridHelper.TraverseRows(itemsControl))
{
node.IsExpanded = false;
}
}
else
{
var parents = this.GetParentItemList(selected);
foreach (object parent in parents)
{
var parentNode = this.FindChildRow(parent, itemsControl);
if (parentNode == null)
{
string msg = "Cannot collapse item '{0}' - the item does not exist in the hierarchy of the tree's bound items.";
msg = String.Format(msg, GetId(parent));
throw new InvalidOperationException(msg);
}
foreach (TreeGridRow item in TreeGridHelper.TraverseRows(itemsControl))
{
//collapse all items that are no ancestors
if (item == parentNode)
{
continue;
}
item.IsExpanded = false;
}
//go a level deeper
itemsControl = parentNode;
}
//finally collapse the item and its siblings
foreach (TreeGridRow item in TreeGridHelper.TraverseRows(itemsControl))
{
item.IsExpanded = false;
}
}
}
/// <summary>
/// 让当前所有行的单元格重新测量。
/// </summary>
private void InvalidateCells()
{
var grid = this.TreeGrid;
if (grid != null && grid.IsColumnsVirtualizingEnabled)
{
var rows = TreeGridHelper.TraverseRows(grid);
foreach (var item in rows)
{
if (item.CellsPanel != null)
{
item.CellsPanel.InvalidateMeasure();
}
}
}
}