API:Vcl.ComCtrls.TTreeView.OnExpanding
Delphi
property OnExpanding: TTVExpandingEvent read FOnExpanding write FOnExpanding;
C++
__property OnExpanding;
Properties
| Type | Visibility | Source | Unit | Parent |
|---|---|---|---|---|
| event | published | Vcl.ComCtrls.pas Vcl.ComCtrls.hpp |
Vcl.ComCtrls | TTreeView |
Description
Occurs when a node is about to be expanded.
Vcl.ComCtrls.TTreeView.OnExpanding inherits from Vcl.ComCtrls.TCustomTreeView.OnExpanding. All content below this line refers to Vcl.ComCtrls.TCustomTreeView.OnExpanding.
Occurs when a node is about to be expanded.
Write an OnExpanding event handler to determine whether a node can be expanded. Set the AllowExpansion parameter to false to prevent the node from expanding.
OnExpanding is an event handler of type Vcl.ComCtrls.TTVExpandingEvent.