Use SendMessage function with CB_GETDROPPEDSTATE message. If Result is true, then the list box of ComboBox is dropped down. You may send this message every second by using Timer component.

procedure TForm1.Timer1Timer(Sender: TObject);
begin
  if SendMessage(ComboBox1.Handle,CB_GETDROPPEDSTATE,0,0)=1 then
    Caption:='ComboBox is opened'
  else Caption:='ComboBox is closed';
end;

This example shows changing of focus between three components on a button click.

var
  i: Integer = 2;
...
procedure TForm1.Button1Click(Sender: TObject);
begin
  case (i mod 3) of
    1: Edit1.SetFocus;
    2: Memo1.SetFocus;
    0: ListBox1.SetFocus;
  end;
  Inc(i);
end;

Add CommCtrl string in uses chapter and use TV_ITEM structure for setting attributes of TreeView items.

uses
  CommCtrl;
...
procedure TForm1.TreeView1GetSelectedIndex(Sender: TObject;
  Node: TTreeNode);
var
  Item: TTVItem;
begin
  FillChar(Item, Sizeof(Item), 0);
  Item.hItem:=Node.ItemId;
  Item.Mask:=TVIF_STATE;
  Item.StateMask:=TVIS_BOLD or TVIS_CUT;
  Item.State:=TVIS_BOLD;
  TreeView_SetItem(Node.Handle, Item);
end;

If you want align menu items text to the right, then you may use this little deceit.

procedure TForm1.FormCreate(Sender: TObject);
var
  i: Integer;
begin
  with MainMenu1 do
    for i:=0 to Items.Count-1 do
      Items[i].Caption:=Chr(8)+Items[i].Caption;
end;