protected override void OnBeforeSelect(TreeViewCancelEventArgs e)
{
base.OnBeforeSelect(e);
// New selection is always the anchor for the next shift selection
if (_anchorNode == null || !IsRangeSelect)
{
_anchorNode = (TreeNodeMS)e.Node;
}
}
protected override void OnAfterSelect(TreeViewEventArgs e)
{
// Save old selection for invalidating
var selectedNodesOld = SelectedNodes.ToArray();
TreeNodeMS node = (TreeNodeMS)e.Node;
// Don't change the selection if this is a right click and the node is in the
// selection.
if (node != null && !(_inRightClick && node.IsInSelection))
{
if (IsDisjointSelect)
{
// Toggle selection on the node
SelectNode(node, !IsNodeSelected(e.Node));
}
else if (IsRangeSelect && !ReferenceEquals(_anchorNode, node))
{
// Figure out top and bottom of the range to be selected
TreeNodeMS upperNode = _anchorNode;
TreeNodeMS bottomNode = node;
if (upperNode.BoundsMS.Top > bottomNode.BoundsMS.Top)
{
Helpers.Swap(ref upperNode, ref bottomNode);
}
// Set new selection to contain all visible nodes between top and bottom
SelectedNodes.Clear();
while (upperNode != null && !ReferenceEquals(upperNode, bottomNode))
{
SelectNode(upperNode, true);
upperNode = (TreeNodeMS)upperNode.NextVisibleNode;
}
SelectNode(bottomNode, true);
}
else
{
// Make this a single selection of the selected node.
SelectedNodes.Clear();
SelectNode(node, true);
}
// Invalidate the changed nodes
var unchangedNodes = new HashSet <TreeNodeMS>(selectedNodesOld.Intersect(SelectedNodes));
InvalidateChangedNodes(selectedNodesOld, unchangedNodes);
InvalidateChangedNodes(SelectedNodes, unchangedNodes);
}
Invalidate();
// Make sure selection is updated before after select event is fired
base.OnAfterSelect(e);
}
protected override void OnMouseDown(MouseEventArgs e)
{
_inRightClick = e.Button == MouseButtons.Right;
if (_inRightClick)
{
TreeNodeMS node = (TreeNodeMS)GetNodeAt(0, e.Y);
if (node != null && node.BoundsMS.Contains(e.Location))
{
SelectedNode = node;
}
}
base.OnMouseDown(e);
}
public void SelectNode(TreeNodeMS node, bool select)
{
if (!select)
{
SelectedNodes.Remove(node);
}
else if (!node.IsInSelection)
{
SelectedNodes.Add(node);
// Make sure all ancestors of this node are expanded
for (var parent = node.Parent; parent != null && !parent.IsExpanded; parent = parent.Parent)
{
parent.Expand();
}
}
node.IsInSelection = select;
}
protected void UpdateSelection()
{
// Remove any nodes from the selection that may have been
// removed from the tree.
var selectedNodes = SelectedNodes.ToArray();
foreach (var node in selectedNodes)
{
if (node.TreeView == null)
{
SelectedNodes.Remove(node);
}
}
// If any nodes were removed from the selection, reset the
// anchor node to the selected node.
if (selectedNodes.Length != SelectedNodes.Count)
{
_anchorNode = (TreeNodeMS)SelectedNode;
}
}
protected override void OnMouseUp(MouseEventArgs e)
{
if (!_inRightClick)
{
TreeNodeMS node = (TreeNodeMS)GetNodeAt(0, e.Y);
if (node != null && node.BoundsMS.Contains(e.Location))
{
// If we are within the bounds of a node and that node is not the selected node,
// make it the selected node. Changing the font of the TreeView at runtime
// apparently does not update node bounds, so we need to do this check in case the
// user clicked outside of the original node bounds.
if (!ReferenceEquals(node, SelectedNode))
{
SelectedNode = node;
}
// Handle cases where clicking on the selected node should change
// the selection.
else
{
// Disjoint selection or the SelectedNode is not in the selection
if (IsDisjointSelect || !IsNodeSelected(node))
{
SelectedNode = null;
}
// More than a single node currently selected, and not performing
// range selection on an existing range selection.
else if (SelectedNodes.Count > 1 &&
(!IsRangeSelect || ReferenceEquals(_anchorNode, SelectedNode)))
{
SelectedNode = null;
}
}
}
}
base.OnMouseUp(e);
_inRightClick = false;
}
public virtual void DrawNodeCustom(Graphics g, int rightEdge)
{
EnsureWidthCustom(g);
Rectangle bounds = BoundsMS;
// Draw dashed lines
var treeView = TreeViewMS;
var dashBrush = treeView.DashBrush;
// Horizontal line.
dashBrush.TranslateTransform(Level % 2 + HorizScrollDiff, 0);
g.FillRectangle(dashBrush, XIndent, bounds.Top + bounds.Height / 2,
TreeViewMS.HORZ_DASH_LENGTH, 1);
// Vertical lines corresponding to the horizontal level of this node.
dashBrush.TranslateTransform(-Level % 2 - HorizScrollDiff, 0);
// Check if this is the Root.
if (ReferenceEquals(this, treeView.Nodes[0]))
{
if (treeView.Nodes.Count > 1)
{
g.FillRectangle(dashBrush, XIndent, bounds.Top + bounds.Height / 2,
1, bounds.Height / 2);
}
}
// Move up the levels of the tree, drawing the corresponding vertical lines.
else
{
try
{
TreeNodeMS curNode = this;
while (curNode != null)
{
dashBrush.TranslateTransform(0, curNode.Level % 2);
if (curNode.NextNode != null)
{
g.FillRectangle(dashBrush, curNode.XIndent, bounds.Top, 1, bounds.Height);
}
else if (curNode == this)
{
g.FillRectangle(dashBrush, curNode.XIndent, bounds.Top, 1, bounds.Height / 2);
}
dashBrush.TranslateTransform(0, -curNode.Level % 2);
curNode = curNode.Parent as TreeNodeMS;
}
}
catch (NullReferenceException)
{
// Ignore a NullReferenceException in this code. The case
// that once caused this has been fixed, but this safeguard is
// kept to avoid showing an unhandled exception to the user.
// If the node being painted is in the process of being removed
// from the tree, then curNode.NextNode will throw a NRE.
}
}
// Draw Collapse/Expand bmps and the image associated with the node.
if (Nodes.Count > 0)
{
Image expandCollapse = IsExpanded ? Resources.Collapse : Resources.Expand;
g.DrawImage(expandCollapse, XIndent - expandCollapse.Width / 2,
bounds.Top + (BoundsMS.Height - expandCollapse.Height + 1) / 2);
}
// Draw images associated with the node.
int imgLocX = XIndent + TreeViewMS.HORZ_DASH_LENGTH;
const int imgWidth = TreeViewMS.IMG_WIDTH, imgHeight = TreeViewMS.IMG_WIDTH;
if (StateImageIndex != -1)
{
Image stateImg = TreeView.StateImageList.Images[StateImageIndex];
g.DrawImageUnscaled(stateImg, imgLocX, bounds.Top + (bounds.Height - imgHeight) / 2, imgWidth, imgHeight);
imgLocX += imgWidth;
}
if (ImageIndex != -1)
{
Image nodeImg = TreeView.ImageList.Images[ImageIndex];
g.DrawImageUnscaled(nodeImg, imgLocX, bounds.Top + (bounds.Height - imgHeight) / 2, imgWidth, imgHeight);
}
DrawTextMS(g);
}
protected void InvalidateNode(TreeNodeMS node)
{
Invalidate(new Rectangle(0, node.BoundsMS.Top, ClientRectangle.Width, node.BoundsMS.Height));
}
