/// <summary>
/// Raises the <see cref="BeforeExpand"/> event.
/// </summary>
/// <param name="e">A <see cref="NodeViewCancelEventArgs"/> that contains the event data.</param>
protected virtual void OnBeforeExpand(NodeViewCancelEventArgs e)
{
if (BeforeExpand != null)
{
BeforeExpand(this, e);
}
}
/// <summary>
/// Raises the <see cref="BeforeSelect"/> event.
/// </summary>
/// <param name="e">A <see cref="NodeViewCancelEventArgs"/> that contains the event data.</param>
protected virtual void OnBeforeSelect(NodeViewCancelEventArgs e)
{
if (BeforeSelect != null)
{
BeforeSelect(this, e);
}
}
/// <summary>
/// Forwards the <see cref="BeforeExpand"/> event.
/// </summary>
/// <param name="e">A <see cref="TreeViewCancelEventArgs"/> that contains the event data.</param>
protected sealed override void OnBeforeExpand(TreeViewCancelEventArgs e)
{
NodeViewCancelEventArgs newArgs = new NodeViewCancelEventArgs((Node)e.Node, e.Cancel,
(NodeViewAction)e.Action);
OnBeforeExpand(newArgs);
e.Cancel = newArgs.Cancel;
base.OnBeforeExpand(e);
// Update the image keys and show the children if the node should get expanded.
if (!e.Cancel)
{
newArgs.Node.UpdateImageKeys();
newArgs.Node.Nodes.Clear();
// Since the node count might have changed meanwhile, check if there are still children available.
List <Node> children = newArgs.Node.GetNodes();
if (children != null)
{
foreach (Node childNode in children)
{
newArgs.Node.Nodes.Add(childNode);
}
}
}
}
/// <summary>
/// Raises the <see cref="BeforeCollapse"/> event.
/// </summary>
/// <param name="e">A <see cref="NodeViewCancelEventArgs"/> that contains the event data.</param>
protected virtual void OnBeforeCollapse(NodeViewCancelEventArgs e)
{
if (BeforeCollapse != null)
{
BeforeCollapse(this, e);
}
}
/// <summary>
/// Raises the <see cref="BeforeCheck"/> event.
/// </summary>
/// <param name="e">A <see cref="NodeViewCancelEventArgs"/> that contains the event data.</param>
protected virtual void OnBeforeCheck(NodeViewCancelEventArgs e)
{
if (BeforeCheck != null)
{
BeforeCheck(this, e);
}
}
/// <summary>
/// Forwards the <see cref="BeforeSelect"/> event.
/// </summary>
/// <param name="e">A <see cref="TreeViewCancelEventArgs"/> that contains the event data.</param>
protected sealed override void OnBeforeSelect(TreeViewCancelEventArgs e)
{
NodeViewCancelEventArgs newArgs = new NodeViewCancelEventArgs((Node)e.Node, e.Cancel,
(NodeViewAction)e.Action);
OnBeforeSelect(newArgs);
e.Cancel = newArgs.Cancel;
base.OnBeforeSelect(e);
}
/// <summary>
/// Forwards the <see cref="BeforeCollapse"/> event.
/// </summary>
/// <param name="e">A <see cref="TreeViewCancelEventArgs"/> that contains the event data.</param>
protected sealed override void OnBeforeCollapse(TreeViewCancelEventArgs e)
{
NodeViewCancelEventArgs newArgs = new NodeViewCancelEventArgs((Node)e.Node, e.Cancel,
(NodeViewAction)e.Action);
OnBeforeCollapse(newArgs);
e.Cancel = newArgs.Cancel;
base.OnBeforeCollapse(e);
// Update the image keys and remove the children if the node should get collapsed.
if (!e.Cancel)
{
newArgs.Node.UpdateImageKeys();
newArgs.Node.Nodes.Clear();
if (newArgs.Node.GetNodeCount() > 0)
{
newArgs.Node.Nodes.Add(new Node(this));
}
}
}