mdimessageu.pas

DelphiWin32核心API参考光盘内容.是学习书籍中的源码,便于学习.

unit MDIMessageU;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  Menus;

type
  TForm1 = class(TForm)
    MainMenu1: TMainMenu;
    CreateChild1: TMenuItem;
    procedure CreateChild1Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;                 tcreateparams

implementation

{$R *.DFM}

{ Register the MDI Child Window Class }
function RegisterClass: Boolean;
var
  WindowClass: TWndClass;
begin
  {setup our new window class}
  WindowClass.Style := CS_HREDRAW or CS_VREDRAW;           {set the class styles}
  WindowClass.lpfnWndProc := @DefMDIChildProc;             {point to the default MDI child window procedure}
  WindowClass.cbClsExtra := 0;                             {no extra class memory}
  WindowClass.cbWndExtra := 0;                             {no extra window memory}
  WindowClass.hInstance := hInstance;                      {the application instance}
  WindowClass.hIcon := LoadIcon(0, IDI_WINLOGO);           {load a predefined logo}
  WindowClass.hCursor := LoadCursor(0, IDC_APPSTARTING);   {load a predefined cursor}
  WindowClass.hbrBackground := COLOR_WINDOW;               {use a predefined color}
  WindowClass.lpszMenuName := nil;                         {no menu}
  WindowClass.lpszClassName := 'TestClass';                {the registered class name}

  {now that we have our class set up, register it with the system}
  Result := Windows.RegisterClass(WindowClass) <> 0;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  {register our child window class}
  if not RegisterClass then
  begin
    ShowMessage('RegisterClass failed');
    Exit;
  end;
end;

procedure TForm1.CreateChild1Click(Sender: TObject);
var
    ChildWnd: HWND;
    MDICreate: TMDICreateStruct;
begin
    {note that the main form has the FormStyle
     property set to fsMDIForm}

    {fill in the members of the MDICreate structure}
    with MDICreate do
    begin
      szClass:='TestClass';                      {our registered class name}
      szTitle:='MDI Child window';               {caption bar test}
      hOwner:=hInstance;                         {the application instance handle}
      X:=CW_USEDEFAULT;                          {default horizontal position}
      Y:=CW_USEDEFAULT;                          {default vertical position}
      CX:=CW_USEDEFAULT;                         {default width}
      CY:=CW_USEDEFAULT;                         {default height}
      style:=WS_OVERLAPPEDWINDOW OR WS_VISIBLE;  {standard, visible window}
      lParam:=0;                                 {no extra information}
    end;

    {now, create the MDI child window using the WM_MDICREATE message}
    ChildWnd:=SendMessage(Form1.ClientHandle, WM_MDICREATE, 0, Longint(@MDICreate));
end;

end.