{
This example is an event handler for a popup menu item. The
handler enables editing of the current item in a TListView
control. The example would also work with a TTreeView
control, or with any instance of a control class derived
from TCustomViewControl.
} 
procedure TForm1.EditItem1Click(Sender: TObject);
begin
  TreeView1.Selected.EditText;
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  MyTreeNode1, MyTreeNode2: TTreeNode;
begin
  with TreeView1.Items do
  begin
    Clear; { remove any existing nodes }
    MyTreeNode1 := Add(nil, 'RootTreeNode1'); { Add a root node }
    { Add a child node to the node just added }
    AddChild(MyTreeNode1,'ChildNode1');

    {Add another root node}
    MyTreeNode2 := Add(MyTreeNode1, 'RootTreeNode2');
    {Give MyTreeNode2 to a child }
    AddChild(MyTreeNode2,'ChildNode2');

    {Change MyTreeNode2 to ChildNode2 }
    { and add a child node to it}
    MyTreeNode2 := TreeView1.Items[3];
    AddChild(MyTreeNode2,'ChildNode2a');

    {Add another child to ChildNode2, after ChildNode2a }
    AddChild(MyTreeNode2,'ChildNode2b');

    {add another root node}
    Add(MyTreeNode1, 'RootTreeNode3');
  end;
end;

procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  PopupMenu1.Popup(Left + X, Top + Y);
end;