【深入浅出MFC】第一章 Win32 基本程序观念

一.以消息为基础，以事件驱动之

MSG msg;while (GetMessage(&msg, NULL, NULL, NULL)) {TranslateMessage(&msg);DispatchMessage(&msg);}

1.消息MSG结构

typedef struct tagMSG{HWND hwnd;UINT message; // WM_xxx，例如WM_MOUSEMOVE，WM_SIZE...WPARAM wParam;LPARAM lParam;DWORD time;POINT pt;} MSG;

2.窗口消息流程图

二.一个具体而微的Win32 程序

#include <Windows.h>#include "resource.h"HINSTANCE _hInstance;HWND _hWnd;static TCHAR szClassName[] = TEXT("Test");static TCHAR szWndName[]  = TEXT("Text");BOOL InitApplication(HINSTANCE hInstance);BOOL InitInstance(HINSTANCE hInstance,int nCmdShow);LRESULT CALLBACK WindowProc( HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam );LRESULT CALLBACK About(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam);////////////////////////////////////////////////////////////////////////////入口程序WinMain//////////////////////////////////////////////////////////////////////////int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow){if (!InitApplication(hInstance)){return FALSE;}if (!InitInstance(hInstance,nCmdShow)){return FALSE;}MSG msg;while (GetMessage(&msg,NULL,0,0)){TranslateMessage(&msg);DispatchMessage(&msg);}return msg.wParam;}////////////////////////////////////////////////////////////////////////////注册窗口类别-——————————InitApplication//////////////////////////////////////////////////////////////////////////BOOL InitApplication(HINSTANCE hInstance){WNDCLASS wndclass;wndclass.cbClsExtra = 0;wndclass.cbWndExtra = 0;wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);wndclass.hCursor      = LoadCursor(NULL,IDC_ARROW);wndclass.hIcon        = LoadIcon(NULL,IDI_APPLICATION);wndclass.hInstance    = hInstance;wndclass.lpszMenuName = MAKEINTRESOURCE(IDR_MENU1);wndclass.lpfnWndProc  = WindowProc;wndclass.lpszClassName = szClassName;wndclass.style = CS_HREDRAW | CS_VREDRAW;return RegisterClass(&wndclass);}////////////////////////////////////////////////////////////////////////////产生窗口-——————————InitApplication//////////////////////////////////////////////////////////////////////////BOOL InitInstance(HINSTANCE hInstance,int nCmdShow){_hInstance = hInstance;_hWnd = CreateWindow(szClassName,szWndName,WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,_hInstance,NULL);if (!_hWnd){return FALSE;}ShowWindow(_hWnd,nCmdShow);UpdateWindow(_hWnd);return TRUE;}////////////////////////////////////////////////////////////////////////////窗口函数------WindowProc//////////////////////////////////////////////////////////////////////////LRESULT CALLBACK WindowProc(HWND hwnd,      // handle to windowUINT uMsg,      // message identifierWPARAM wParam,  // first message parameterLPARAM lParam   // second message parameter){int wmId, wmEvent;switch (uMsg){case WM_COMMAND:wmId = LOWORD(wParam);wmEvent = HIWORD(wParam);switch (wmId){case IDM_ABOUT:DialogBox(_hInstance,MAKEINTRESOURCE(IDD_ABOUT), hwnd, (DLGPROC)About);break;case IDM_EXIT:DestroyWindow(hwnd);break;default:return(DefWindowProc(hwnd, uMsg, wParam, lParam));}break;case WM_DESTROY:PostQuitMessage(0);break;default:return DefWindowProc(hwnd, uMsg, wParam, lParam);}return 0;}////////////////////////////////////////////////////////////////////////////对话框函数——About//////////////////////////////////////////////////////////////////////////LRESULT CALLBACK About(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam){switch (uMsg){case WM_INITDIALOG:return TRUE;case WM_COMMAND:if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL){EndDialog(hwnd,TRUE);return TRUE;}break;}return FALSE;}

1.程序入口点 WinMain

int WINAPI WinMain(  HINSTANCE hInstance,  // handle to current instance  HINSTANCE hPrevInstance,  // handle to previous instance  LPSTR lpCmdLine,      // pointer to command line  int nCmdShow          // show state of window);

2.窗口类别之注册与窗口之诞生

3.消息循环

while (GetMessage(&msg, NULL, NULL, NULL)) {TranslateMessage(&msg);DispatchMessage(&msg);}

4.窗口的生命中枢：窗口函数

LRESULT CALLBACK WindowProc(  HWND hwnd,      // handle to window  UINT uMsg,      // message identifier  WPARAM wParam,  // first message parameter  LPARAM lParam   // second message parameter);

窗口函数设计为callback 形式，才能开放出一个接口给操作系统叫用。

5.消息映射的雏形

//定义一个MSGMAP_ENTRY 结构和一个dim 宏：struct MSGMAP_ENTRY {UINT nMessage;LONG (*pfn)(HWND, UINT, WPARAM, LPARAM);};#define dim(x) (sizeof(x) / sizeof(x[0]))

组织两个数组_messageEntries[ ] 和_commandEntries[ ]

// 消息与处理例程之对照表格struct MSGMAP_ENTRY _messageEntries[] ={WM_CREATE, OnCreate,WM_PAINT, OnPaint,WM_SIZE, OnSize,WM_COMMAND, OnCommand,WM_SETFOCUS, OnSetFocus,WM_CLOSE, OnClose,WM_DESTROY, OnDestroy,} ;

// Command-ID struct MSGMAP_ENTRY _commandEntries ={IDM_ABOUT, OnAbout,IDM_FILEOPEN, OnFileOpen,IDM_SAVEAS, OnSaveAs,} 

6.对话框的运作

对话框函数（dialog procedure）。其类型非常类似窗口函数，但是它通常只处理WM_INITDIALOG 和WM_COMMAND 两个消息.

Modal 对话框的激活与结束，靠的是DialogBox 和EndDialog 两个API 函数.

三.Windows 程序的生与死

四.空闲时间的处理：OnIdle

while (TRUE) {    if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE) {        if (msg.message== WM_QUIT)            break;        TranslateMessage(&msg);        DispatchMessage(&msg);    }    else {       OnIdle();    }}

GetMessage 会过门不入，于是操作系统再去照顾其它人。

PeekMessage 会取回控制权，使程序得以执行一段时间。于是上述消息循环进入OnIdle 函数中。

进程与执行线程