恐怖问题

Question

unit Win32;interfaceuses
Windows,Messages,SysUtils;const
AppName = 'HelloWorld';
type
//定义一个自己的类
TMyClass = class
public
//有一个窗体注册函数
function WinRegister:Boolean;
//创建窗体句柄函数
function WinCreate:HWND;
//执行窗体函数
function ExecWin(hWnd:HWND):LongInt;
//消息循环函数
function WindowProc(hWnd:HWND;
aMessage:UINT;
wParam,lParam:LongInt):LongInt;stdcall;export;
//消息销毁函数
procedure On_Destroy(hWnd: HWnd; var Meg: TWMDestroy);
end;implementationfunction TMyClass.WinRegister:Boolean;
var 
WCL: TWndClass; 
begin 
WCL.hInstance := hInstance; 
with WCL do 
begin 
Style := CS_HREDRAW or CS_VREDRAW; 
lpfnWndProc := @WindowProc;
hIcon := LoadIcon( hInstance, IDI_APPLICATION ); 
hCursor := LoadCursor( 0, IDC_ARROW ); 
hbrBackGround := hBrush( COLOR_WINDOW ); 
lpszMenuName := 'FontMenu'; 
lpszClassName := AppName; 
cbClsExtra := 0; 
cbWndExtra := 0; 
end; 
Result := RegisterClass( WCL ) <> 0; // 登记窗口类 API 
end;function TMyClass.WinCreate:HWND;
begin 
Result := CreateWindow( AppName, 'Win32 SDK for Delphi', 
WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 
625, 275, HWND_DESKTOP, 0, hInstance, nil ); 
end;function TMyClass.ExecWin(hWnd:HWND):LongInt;
var
aMessage: TMsg;
begin
ShowWindow( hWnd, CmdShow ); // 显示窗口 API
UpdateWindow( hWnd ); // 重新显示窗口 API
while GetMessage( aMessage, 0, 0, 0 ) do // 取消息 API
begin
TranslateMessage( aMessage ); // 转换字符消息 API 
DispatchMessage( aMessage ); // 发送消息到指定窗口 API
end;
Result := aMessage.wParam; 
end;function TMyClass.WindowProc(hWnd:HWND;
aMessage:UINT;
wParam,lParam:LongInt):LongInt;stdcall;export;
var
aMeg: TMessage;
begin
aMeg.Msg := aMessage;
aMeg.WParam := wParam;
aMeg.LParam := lParam;
aMeg.Result := 0;
case aMessage of
//WM_CREATE: On_Create( hWindow, TWMCreate( aMeg ) );
WM_DESTROY: On_Destroy( hWnd, TWMDestroy( aMeg ) );
//WM_COMMAND: On_Command( hWindow, TWMCommand( aMeg ) );
//WM_NEWFONT: NewFont( lParam );
//WM_STARTFONTS: StartFont( hWindow );
// 调用缺省的窗口函数 API
else aMeg.Result := DefWindowProc( hWnd, aMessage, wParam, lParam );
end;
Result := aMeg.Result;
end;procedure TMyClass.On_Destroy(hWnd: HWnd; var Meg: TWMDestroy);
begin
PostQuitMessage(0);
end;end.
我只想显示一个窗口，不要显示什么Font文字什么的，所以我注释了一些，一下是错误：
[Error] Win32.pas(38): Variable required
[Warning] Win32.pas(53): Constant expression violates subrange bounds
[Warning] Win32.pas(53): Constant expression violates subrange bounds
[Warning] Win32.pas(61): Symbol 'CmdShow' is specific to a platform

Answer 1

路过，Variable required
就一个错误，可能你调用哪个函数 传递的需要变量，你传了常量

Answer 2

改
lpfnWndProc := @WindowProc;
为:
lpfnWndProc := @TMyClass.WindowProc;
就可以编译了

Answer 3

刚好我实现了一个 给你吧  直接在工程文件里 复制 粘贴program Project1;uses
  Forms,
  Windows,
  SysUtils,
  Messages,
  Dialogs;type
  TMyForm = class(TObject)
  private
    winclass:WNDCLASSA;
    hwindow:HWND;
    Amsg:TMsg;
    FAppName:string;
    FWndproc:TFNAPCProc;
    function winregister():Boolean;
    procedure CreateMyWindow;
  public
    constructor Create;
    destructor Destroy;override;
    procedure WinCreate;
    procedure MyRun;
    procedure CreateButton(x,y:Integer;className,windowName:string);
    property ApplicationName : string  read FAppName write FAppName;
    property MyProcedure : TFNAPCProc read FWndproc write FWndproc;
  end;const
  AppName = 'Myclass';var
  Mywindow:TMyForm;
{ TMyForm }constructor TMyForm.Create;
beginend;procedure TMyForm.CreateButton(x,y:Integer;className,windowName:string);
var
  hMyButton:HWND;
begin
  hMyButton:=CreateWindow(PAnsiChar(className),PAnsiChar(windowName),WS_VISIBLE or WS_Child or BS_Bitmap,
    x,y,65,24,hwindow,0,system.MainInstance,nil);
  ShowWindow(hMyButton,CmdShow);
  ShowWindow(hMyButton,SW_SHOWNORMAL);
  UpdateWindow(hMyButton);
end;procedure TMyForm.CreateMyWindow;
begin
  hwindow := CreateWindowEx(WS_EX_CLIENTEDGE,PAnsiChar(FAppName),AppName,WS_OVERLAPPEDWINDOW,100,
  100,600,400,0,0,SYSTEM.MainInstance,nil); // hwindow := CreateWindow(AppName,'创建窗口',WS_OVERLAPPED,CW_USEDEFAULT,
 //   CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,0,0,SYSTEM.MainInstance,nil);
  if hwindow <> 0 then
  begin
    ShowWindow(hwindow,CmdShow);
    ShowWindow(hwindow,SW_SHOWNORMAL);
    UpdateWindow(hwindow);
    CreateButton(75,175,'BUTTON','Mybutton1');
    CreateButton(75,275,'BUTTON','Mybutton2');
  end;
end;destructor TMyForm.Destroy;
begin  inherited;
end;procedure TMyForm.MyRun;
begin
  while GetMessage(Amsg,0,0,0) do
  begin
    TranslateMessage(Amsg);
    DispatchMessage(Amsg);
  end;
  Halt(Amsg.wParam);
end;procedure TMyForm.WinCreate;
begin
  if winregister then
  begin
    CreateMyWindow;
  end;
end;function TMyForm.winregister: Boolean;
begin
  winclass.style := CS_HREDRAW or CS_VREDRAW;
  winclass.lpfnWndProc := FWndproc;
  winclass.cbClsExtra := 0;
  winclass.cbWndExtra := 0;
  winclass.hInstance := System.MainInstance;
  winclass.hIcon := LoadIcon(0,IDI_APPLICATION);
  winclass.hCursor := LoadCursor(0,IDC_ARROW);
  winclass.hbrBackground := GetStockObject(WHITE_BRUSH);
  winclass.lpszMenuName := nil;
  winclass.lpszClassName := PChar(FAppName);
  Result := RegisterClass(winclass)<> 0;
end;function  WindowProc(hwnd:HWND;umsg:UINT;wParam:WPARAM;lParam:LPARAM):LRESULT;stdcall;export;
var
  dc:HDC;
  ps:TPaintStruct;
  r:TRect;
  Curxy:TPoint;
begin
  WindowProc := 0 ;
  case umsg of
  WM_PAINT:
  begin
    dc := BeginPaint(hwnd,ps);
    GetClientRect(hwnd,r);
    DrawText(dc,'哈哈哈',-1,r,DT_SINGLELINE or DT_CENTER or DT_VCENTER);
    EndPaint(hwnd,ps);
    Exit;
  end;
  WM_DESTROY:
  begin
    PostQuitMessage(0);
    Exit;
  end;
  WM_COMMAND:
  begin
    if GetCursorPos(Curxy) then// 获取鼠标坐标
      if Curxy.Y < 350 then
      begin
        ShowMessage('按钮1按下了');
      end
      else
      begin
        ShowMessage('按钮2按下了');
      end;
  end;
 end;
 WindowProc := DefWindowProc(hwnd,umsg,wParam,lParam); 
end;begin
  Mywindow := TMyForm.Create;
  Mywindow.ApplicationName := AppName;
  Mywindow.FWndproc := TFNAPCProc(@WindowProc);
  Mywindow.WinCreate;
  try
    Mywindow.MyRun;
   // Mywindow.CreateButton;
  finally
    FreeAndNil(Mywindow);
  end;  
end.

Answer 4

各位大哥，我把我的程序按照规定改动了一下：
unit Win32;interfaceuses
  Windows,Messages,SysUtils;const
  AppName = 'HelloWorld';
type
  //定义一个自己的类
  TMyClass = class
  public
    //有一个窗体注册函数
    function WinRegister:Boolean;
    //创建窗体句柄函数
    function WinCreate:HWND;
    //执行窗体函数
    function ExecWin(hWnd:HWND):LongInt;
  end;  //消息销毁函数
    procedure On_Destroy(hWnd: HWnd; var Meg: TWMDestroy);
  //消息循环函数
  function WindowProc(hWnd:HWND;
                      aMessage:UINT;
                      wParam,lParam:LongInt):LongInt;stdcall;export;implementationfunction TMyClass.WinRegister:Boolean;
var 
  WCL: TWndClass; 
begin 
  WCL.hInstance := hInstance; 
  with WCL do 
  begin 
    Style := CS_HREDRAW or CS_VREDRAW; 
    lpfnWndProc := @WindowProc;
    hIcon := LoadIcon( hInstance, IDI_APPLICATION ); 
    hCursor := LoadCursor( 0, IDC_ARROW ); 
    hbrBackGround := hBrush( COLOR_WINDOW ); 
    lpszMenuName := nil; 
    lpszClassName := AppName; 
    cbClsExtra := 0; 
    cbWndExtra := 0; 
  end; 
  Result := RegisterClass( WCL ) <> 0;  // 登记窗口类 API 
end;function TMyClass.WinCreate:HWND;
begin 
  Result := CreateWindow( AppName,
                          'Win32 SDK for Delphi',
                          WS_OVERLAPPEDWINDOW,
                          100,
                          100,
                          635,
                          432,
                          0,
                          0,
                          hInstance,
                          nil );
end;function TMyClass.ExecWin(hWnd:HWND):LongInt;
var
  aMessage: TMsg;
begin
  ShowWindow( hWnd, CmdShow );  // 显示窗口 API
  UpdateWindow( hWnd );        // 重新显示窗口 API
  while GetMessage( aMessage, 0, 0, 0 ) do // 取消息 API
  begin
    TranslateMessage( aMessage );  // 转换字符消息 API 
    DispatchMessage( aMessage );    // 发送消息到指定窗口 API
  end;
  Result := aMessage.wParam; 
end;function WindowProc(hWnd:HWND;
                        aMessage:UINT;
                        wParam,lParam:LongInt):LongInt;stdcall;export;
                        var
                          aMeg: TMessage;
                        begin
                          aMeg.Msg := aMessage;
                          aMeg.WParam := wParam;
                          aMeg.LParam := lParam;
                          aMeg.Result := 0;
                            case aMessage of
                                //WM_CREATE: On_Create( hWindow, TWMCreate( aMeg ) );
                                WM_DESTROY: On_Destroy( hWnd, TWMDestroy( aMeg ) );
                                //WM_COMMAND: On_Command( hWindow, TWMCommand( aMeg ) );
                                //WM_NEWFONT: NewFont( lParam );
                                //WM_STARTFONTS: StartFont( hWindow );
                                // 调用缺省的窗口函数 API
                            else aMeg.Result := DefWindowProc( hWnd, aMessage, wParam, lParam );
                            end;
                        Result := aMeg.Result;
                        end;procedure On_Destroy(hWnd: HWnd; var Meg: TWMDestroy);
begin
  PostQuitMessage(0);
end;end.我这个改过后运行没有错误，但是，也没有弹出窗口，这是为什么，我也没找到哪里出现的逻辑错误，各位高手大哥帮帮忙，小弟谢谢了

Answer 5

我测试过了 你的程序没问题。我是这样测试的，你可以参考
1 定义一个类对象在私有部分。如  haha:TMyClass;在定义一个hand:THandle;
2 在一个按钮的OnClick 键入如下代码(我没有检查错误)
procedure TForm1.btn1Click(Sender: TObject);
begin
   haha.WinRegister;
   hand := haha.WinCreate;
   haha.ExecWin(hand);
end;
就能出现你要的窗口。建议你把CmdShow 改为SW_SHOW。要不会出一个警告。我的是D6