Delphi After Events

aftershow.pas

uses
  WinAPI.Messages;

const
  WM_AFTER_SHOW = WM_USER + 300; // custom message
  WM_AFTER_CREATE = WM_USER + 301; // custom message
type
  TForm1 = class(TForm)
    // After Resize Event
    procedure WMExitSizeMove(var Message: TMessage); message WM_EXITSIZEMOVE;  
    // OnShow event
    procedure FormShow(Sender: TObject);
    // OnCreate event
    procedure FormCreate(Sender: TObject);
  private
    procedure WmAfterShow(var Msg: TMessage); message WM_AFTER_SHOW;
    procedure WmAfterCreate(var Msg: TMessage); message WM_AFTER_CREATE;
  public
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.WMExitSizeMove(var Message: TMessage);
begin
  ShowMessage('After resize');
end;

procedure TForm1.WmAfterShow(var Msg: TMessage);
begin
  ShowMessage('WM_AFTER_SHOW received!');
end;

procedure TForm1.WmAfterCreate(var Msg: TMessage);
begin
  ShowMessage('WM_AFTER_CREATE received!');
end;

procedure TForm1.FormShow(Sender: TObject);
begin
  // Post the custom message WM_AFTER_SHOW to our form
  PostMessage(Self.Handle, WM_AFTER_SHOW, 0, 0);
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  // Post the custom message WM_AFTER_CREATE to our form
  PostMessage(Self.Handle, WM_AFTER_CREATE, 0, 0);
end;