WTL-A basic WTL application

一个基本的WTL程序：

一.实现代码

1.包含常用头文件和宏定义，用于简化WTL程序编写的自定义头文件：WTLHelper.h

//WTLHelper.h
#pragma once
#define WINVER 0x0601           //win7
#define _WIN32_WINNT 0x0601     //win7
#define _WIN32_IE 0x0800        //IE 8.0
#define _RICHEDIT_VER 0x0300
#define _WTL_USE_CSTRING    //use CString class in WTL
//ATL header files
#include <atlbase.h>
#include <atlapp.h>
//WTL header files
#include <atlwin.h>     //CWindowImpl
#include <atlcrack.h>   //BEGIN_MSG_MAP_EX, message crack
#include <atlmisc.h>    //CString, CRect, CSize
#ifndef WTLHELPER_NOT_USE_COMMON_CONTROL_STYLE
#if defined _M_IX86
#pragma comment(linker, "/manifestdependency:\"type='win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' processorArchitecture='x86' publicKeyToken='6595b64144ccf1df' language='*'\"")
#elif defined _M_IA64
#pragma comment(linker, "/manifestdependency:\"type='win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' processorArchitecture='ia64' publicKeyToken='6595b64144ccf1df' language='*'\"")
#elif defined _M_X64
#pragma comment(linker, "/manifestdependency:\"type='win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' processorArchitecture='amd64' publicKeyToken='6595b64144ccf1df' language='*'\"")
#else
#pragma comment(linker, "/manifestdependency:\"type='win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' processorArchitecture='*' publicKeyToken='6595b64144ccf1df' language='*'\"")
#endif
#endif // WTL_NOT_ADD_COMMON_CONTROL_MENIFEST
#ifndef ATLASSERTHR
#define ATLASSERTHR(hr) ATLASSERT(SUCCEEDED((hr)))
#endif  // ATLASSERTHR

2.预编译头文件：stdafx.h

//stdafx.h
#pragma once
#include "WTLHelper.h"
extern CAppModule g_AppModule;

3.主窗口定义：MainWindow.h

//MainWindow.h
#pragma once
#include "stdafx.h"
typedef CWinTraits<WS_OVERLAPPEDWINDOW> CMainWinTraits;
class CMainWindow :
    public CWindowImpl<CMainWindow,CWindow,CMainWinTraits>
{
public:
    DECLARE_WND_CLASS(_T("Basic_Main_Window"))
    BEGIN_MSG_MAP_EX(CMainWindow)
        MSG_WM_CREATE(OnCreate)
        MSG_WM_DESTROY(OnDestroy)
        MSG_WM_PAINT(OnPaint)
        MSG_WM_LBUTTONDOWN(OnLButtonDown)
    END_MSG_MAP()
public:
    CMainWindow()
    {
        CWndClassInfo& wci = GetWndClassInfo();
        if (!wci.m_atom)    //The window class has not been registered yet
        {
            //Set the background brush of window class
            wci.m_wc.hbrBackground = AtlGetStockBrush(GRAY_BRUSH);
        }
    }
    
    int OnCreate(LPCREATESTRUCT /*lpCreateStruct*/)
    {
        //Create font to draw text in the client window
        CLogFont logFont;
        TCHAR fontName[] = _T("Arial");
        wcscpy_s(logFont.lfFaceName,fontName);
        logFont.lfHeight = 60;
        logFont.lfItalic = TRUE;
        logFont.lfWeight = FW_BOLD;
        logFont.lfStrikeOut = TRUE;
        m_FontText.CreateFontIndirect(&logFont);
        return 0;
    }
    void OnDestroy()
    {
        PostQuitMessage(0);
    }
    
    void OnPaint(CDCHandle)
    {
        CPaintDC dc(m_hWnd);
        
        //Do painting work here...
        CRect rc;
        GetClientRect(&rc);
        dc.SaveDC();
        dc.SelectFont(m_FontText);
        LPCTSTR text = _T("A basic WTL application.");
        dc.DrawText(text,-1,&rc,DT_CENTER|DT_VCENTER|DT_SINGLELINE);
        
        dc.RestoreDC(-1);
    }
    
    void OnLButtonDown(UINT /*nFlags*/, CPoint /*point*/)
    {
        MessageBox(_T("Left button down!"),_T("Main window message"),MB_OK|MB_ICONINFORMATION);
    }
private:
    CFont m_FontText;
};

4.主程序文件：BasicApp.cpp

//BasicApp.cpp
#include "stdafx.h"
#include "MainWindow.h"
CAppModule g_AppModule;
int Run(int nShowCmd)
{
    CMessageLoop msgLoop;
    g_AppModule.AddMessageLoop(&msgLoop);
    //Create and show main window
    CMainWindow mainWnd;
    mainWnd.Create(NULL,NULL,_T("WTL main window"));
    mainWnd.ShowWindow(nShowCmd);
    mainWnd.CenterWindow();
    //Start message loop
    int result = msgLoop.Run();
    g_AppModule.RemoveMessageLoop();
    return result;
}
int WINAPI _tWinMain(HINSTANCE hInstance, HINSTANCE, LPTSTR /*lpCmdLine*/,int nShowCmd)
{
    HRESULT hr = g_AppModule.Init(NULL,hInstance);
    ATLASSERTHR(hr);
    int result = Run(nShowCmd);
    g_AppModule.Term();
    return result;
}

5.运行效果

二.小技巧

1.消息映射的添加：

WTL的消息映射中，任何一个标准windows消息WM_XXX都直接对于于MESSAGE_MAP中的一项MSG_WM_XXX，比如WM_PAINT消息所对应的消息映射项为MSG_WM_PAINT。

如果是手动添加消息映射，可以先在MESSAGE_MAP中添加”MSG_WM_PAINT()”，然后按F12，VS会跳转到此消息映射的定义中，即跳转到atlcrack.h的如下代码处：

//atlcrack.h
// void OnPaint(CDCHandle dc)
#define MSG_WM_PAINT(func) \
  if (uMsg == WM_PAINT) \
  { \
    SetMsgHandled(TRUE); \
    func((HDC)wParam); \
    lResult = 0; \
    if(IsMsgHandled()) \
      return TRUE; \
  }

在代码的注释中可以找到MSG_WM_PAINT()所对应的消息响应函数的原型，于是，可以手动的添加此消息的响应函数：

    void OnPaint(CDCHandle)
    {
        CPaintDC dc(m_hWnd);
        
        //Do painting work here...
        //...
    }

也可以使用一个开源的小工具VisualFC帮助添加消息映射（安装方法见其说明文档）：

2.修改WNDCLASSEX结构的默认值：

Win32在注册窗口类时所用到的WNDCLASSEX结构有很多字段，用于设置窗口类的行为特征，比如hbrBackground字段用于设置窗口背景画刷。

在WTL中，若要修改默认WNDCLASSEX的设置，可以在窗口类注册前（比如在窗口类的构造函数中）调用GetWndClassInfo()修改窗口类结构：

CWndClassInfo& wci = GetWndClassInfo();
if (!wci.m_atom)    //The window class has not been registered yet
{
     //Set the background brush of window class
     wci.m_wc.hbrBackground = AtlGetStockBrush(GRAY_BRUSH);
}