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copied!<p>It doesn't really make any difference if the <code>Data</code> of nodes hold a pointer to a frame or any other kind of object, typecast the pointer to the type of object it holds.</p> <p>Below code adds two frames ('Frame2' and 'Frame3', created by the IDE - much like a new form), as nodes of a TreeView, and sets the visibility of the selected node's frame to true and the deselected one's to false.</p> <pre><code>type TForm1 = class(TForm) TreeView1: TTreeView; procedure FormCreate(Sender: TObject); procedure TreeView1Change(Sender: TObject; Node: TTreeNode); procedure TreeView1Changing(Sender: TObject; Node: TTreeNode; var AllowChange: Boolean); procedure FormDestroy(Sender: TObject); end; var Form1: TForm1; implementation uses Unit2, Unit3; {$R *.dfm} procedure TForm1.FormCreate(Sender: TObject); begin TreeView1.Align := alLeft; with TFrame(TreeView1.Items.AddObject(nil, 'Frame2', TFrame2.Create(nil)).Data) do begin Visible := False; Parent := Self; Align := alClient; end; with TFrame(TreeView1.Items.AddObject(nil, 'Frame3', TFrame3.Create(nil)).Data) do begin Visible := False; Parent := Self; Align := alClient; end; end; procedure TForm1.FormDestroy(Sender: TObject); var i: Integer; begin for i := 0 to TreeView1.Items.Count - 1 do TFrame(TreeView1.Items[i].Data).Free; end; procedure TForm1.TreeView1Change(Sender: TObject; Node: TTreeNode); begin TFrame(Node.Data).Visible := True; end; procedure TForm1.TreeView1Changing(Sender: TObject; Node: TTreeNode; var AllowChange: Boolean); begin if Assigned((Sender as TTreeView).Selected) then TFrame(TTreeView(Sender).Selected.Data).Visible := False; end; </code></pre>

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