TCustomTreeView.OnExpanded property
Event handler signalled when a node on the tree view control has been expanded.
Declaration
property OnExpanded: TTVExpandedEvent read FOnExpanded write FOnExpanded;Description
OnExpanded is a
TTVExpandedEvent property with the event
handler signalled when a node on the tree view control has been expanded. It
is signalled (when assigned) from the Expand method, and occurs after child
nodes have been displayed and scroll bars for the control have been updated.
Values in the States property have already been updated to indicate that a
node has been expanded and that visible items need to be updated.
An application can implement a handler routine to perform actions needed when the tree node or its children become visible on the control.
Arguments for the event handler include:
- Sender
- The object instance (TCustomTreeView) for the event.
- Node
- The TTreeNode instance with the node expanded on the tree view control.
Use OnExpanding to perform actions needed immediately prior to expanding a node on the tree view control.
Use OnCollapsing and OnCollapsed to perform actions before or after a node is collapsed on the tree view control.
See also
An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.