Drop down menu for TButton - delphi

Question

I am trying to simulate a drop down menu for a TButton, as shown below:
procedure DropMenuDown(Control: TControl; PopupMenu: TPopupMenu);
var
APoint: TPoint;
begin
APoint := Control.ClientToScreen(Point(0, Control.ClientHeight));
PopupMenu.Popup(APoint.X, APoint.Y);
end;
procedure TForm1.Button1MouseUp(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
begin
if Button = mbLeft then
begin
DropMenuDown(Button1, PopupMenu1);
// ReleaseCapture;
end;
end;
The problem is that when the menu is dropped down, if I click the button again I would like the menu to close, but instead it drops down again.
I am looking for a solution specifically for generic Delphi TButton not any 3rd Party equivalent.

Answer 1

After reviewing the solution provided by Whiler & Vlad, and comparing it to the way WinSCP implements the same thing, I'm currently using the following code:
unit ButtonMenus;
interface
uses
Vcl.Controls, Vcl.Menus;
procedure ButtonMenu(Control: TControl; PopupMenu: TPopupMenu);
implementation
uses
System.Classes, WinApi.Windows;
var
LastClose: DWord;
LastPopupControl: TControl;
LastPopupMenu: TPopupMenu;
procedure ButtonMenu(Control: TControl; PopupMenu: TPopupMenu);
var
Pt: TPoint;
begin
if (Control = LastPopupControl) and (PopupMenu = LastPopupMenu) and (GetTickCount - LastClose < 100) then begin
LastPopupControl := nil;
LastPopupMenu := nil;
end else begin
PopupMenu.PopupComponent := Control;
Pt := Control.ClientToScreen(Point(0, Control.ClientHeight));
PopupMenu.Popup(Pt.X, Pt.Y);
{ Note: PopupMenu.Popup does not return until the menu is closed }
LastClose := GetTickCount;
LastPopupControl := Control;
LastPopupMenu := PopupMenu;
end;
end;
end.
It has the advantage of not requiring any code changes to the from, apart from calling ButtonMenu() in the onClick handler:
procedure TForm1.Button1Click(Sender: TObject);
begin
ButtonMenu(Button1, PopupMenu1);
end;

Answer 2

Following our (Vlad & I) discussion, you use a variable to know when the popup was last opened to choose if you display the popupmenu or cancel the mouse event:
unit Unit4;
interface
uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.Menus, Vcl.StdCtrls;
type
TForm4 = class(TForm)
PopupMenu1: TPopupMenu;
Button1: TButton;
fgddfg1: TMenuItem;
fdgdfg1: TMenuItem;
procedure FormCreate(Sender: TObject);
procedure Button1Click(Sender: TObject);
procedure Button1MouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
private
{ Private declarations }
cMenuClosed: Cardinal;
public
{ Public declarations }
end;
var
Form4: TForm4;
implementation
{$R *.dfm}
procedure DropMenuDown(Control: TControl; PopupMenu: TPopupMenu);
var
APoint: TPoint;
begin
APoint := Control.ClientToScreen(Point(0, Control.ClientHeight));
PopupMenu.Popup(APoint.X, APoint.Y);
end;
procedure TForm4.Button1Click(Sender: TObject);
begin
DropMenuDown(Button1, PopupMenu1);
cMenuClosed := GetTickCount;
end;
procedure TForm4.Button1MouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
begin
if (Button = mbLeft) and not ((cMenuClosed + 100) < GetTickCount) then
begin
ReleaseCapture;
end;
end;
procedure TForm4.FormCreate(Sender: TObject);
begin
cMenuClosed := 0;
end;
end.