The ListView of Making Planar column head in Delphi

Create a new application, place a ListView control and a button control on the form, and then paste the following code, which references the API and constants in your code to the Windows unit by pressing the CTRL key and then clicking the left mouse button

unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ComCtrls;
type
TForm1 = class(TForm)
ListView1: TListView;
Button1: TButton;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.Button1Click(Sender: TObject);
const
LVM_GETHEADER = $1000 + 31;
var
hHeader: THandle;
style: dWord;
begin
hHeader := SendMessage(ListView1.Handle, LVM_GETHEADER, 0, 0);
style := GetWindowLong(hHeader, GWL_STYLE);
style := style xor $2;
SetWindowLong(hHeader, GWL_STYLE, style);
SetWindowPos(ListView1.Handle, Form1.Handle, 0, 0, 0, 0,SWP_NOZORDER or SWP_NOSIZE or SWP_NOMOVE or SWP_DRAWFRAME);
end;
end.