WTL改变对话框大小

1、让对话框从CdialogResize类继承过来：

class CMainDlg : public CDialogImpl<CMainDlg>,
public CDoubleBufferImpl<CMainDlg>,
public CDialogResize<CMainDlg>

2、添加消息路由

BEGIN_MSG_MAP(CMainDlg)
CHAIN_MSG_MAP(CDialogResize<CMainDlg>)
CHAIN_MSG_MAP(CDoubleBufferImpl<CMainDlg>)
MESSAGE_HANDLER(WM_INITDIALOG, OnInitDialog)
COMMAND_ID_HANDLER(IDCANCEL, OnCancel)
END_MSG_MAP()

3、添加消息映射

BEGIN_DLGRESIZE_MAP(CMainDlg)
DLGRESIZE_CONTROL(IDC_STATIC_INPUT,  DLSZ_SIZE_X)
DLGRESIZE_CONTROL(IDC_STATIC_SEARCH, DLSZ_SIZE_X | DLSZ_SIZE_Y)
END_DLGRESIZE_MAP()

4、在OnInitDialog()中调用DlgResize_Init();

当对话框存在GroupBox的话，需要将GroupBox设置为透明背影

Transparent:true

测试代码：

MainDlg.h

// MainDlg.h : interface of the CMainDlg class
//
/////////////////////////////////////////////////////////////////////////////

#pragma once
#include <gdiplus.h>

class CMainDlg : public CDialogImpl<CMainDlg>,
	public CDoubleBufferImpl<CMainDlg>,
	public CDialogResize<CMainDlg>
{
public:
	enum { IDD = IDD_MAINDLG };

	BEGIN_MSG_MAP(CMainDlg)
		CHAIN_MSG_MAP(CDialogResize<CMainDlg>)
		CHAIN_MSG_MAP(CDoubleBufferImpl<CMainDlg>)
		MESSAGE_HANDLER(WM_INITDIALOG, OnInitDialog)
		COMMAND_ID_HANDLER(IDCANCEL, OnCancel)
	END_MSG_MAP()

	BEGIN_DLGRESIZE_MAP(CMainDlg)
		DLGRESIZE_CONTROL(IDC_STATIC_INPUT,  DLSZ_SIZE_X)
		DLGRESIZE_CONTROL(IDC_STATIC_SEARCH, DLSZ_SIZE_X | DLSZ_SIZE_Y)
	END_DLGRESIZE_MAP()

// Handler prototypes (uncomment arguments if needed):
//	LRESULT MessageHandler(UINT /*uMsg*/, WPARAM /*wParam*/, LPARAM /*lParam*/, BOOL& /*bHandled*/)
//	LRESULT CommandHandler(WORD /*wNotifyCode*/, WORD /*wID*/, HWND /*hWndCtl*/, BOOL& /*bHandled*/)
//	LRESULT NotifyHandler(int /*idCtrl*/, LPNMHDR /*pnmh*/, BOOL& /*bHandled*/)

	LRESULT OnInitDialog(UINT /*uMsg*/, WPARAM /*wParam*/, LPARAM /*lParam*/, BOOL& /*bHandled*/);
	LRESULT OnCancel(WORD /*wNotifyCode*/, WORD wID, HWND /*hWndCtl*/, BOOL& /*bHandled*/);
	void DoPaint(CDCHandle dc);
private:
	Gdiplus::GdiplusStartupInput gGdiInput;
	ULONG token;
};

MainDlg.cpp

// MainDlg.cpp : implementation of the CMainDlg class
//
/////////////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "resource.h"

#include "MainDlg.h"
#pragma comment(lib, "GdiPlus.lib")

LRESULT CMainDlg::OnInitDialog(UINT /*uMsg*/, WPARAM /*wParam*/, LPARAM /*lParam*/, BOOL& /*bHandled*/)
{
	// center the dialog on the screen
	CenterWindow();

	// set icons
	HICON hIcon = AtlLoadIconImage(IDR_MAINFRAME, LR_DEFAULTCOLOR, ::GetSystemMetrics(SM_CXICON), ::GetSystemMetrics(SM_CYICON));
	SetIcon(hIcon, TRUE);
	HICON hIconSmall = AtlLoadIconImage(IDR_MAINFRAME, LR_DEFAULTCOLOR, ::GetSystemMetrics(SM_CXSMICON), ::GetSystemMetrics(SM_CYSMICON));
	SetIcon(hIconSmall, FALSE);

	GdiplusStartup(&token, &gGdiInput, NULL);

	DlgResize_Init();
	return TRUE;
}

void CMainDlg::DoPaint(CDCHandle dc)
{
	RECT rect;
	GetClientRect(&rect);
	
	Gdiplus::Graphics g(dc);
	Gdiplus::Image im(_T("res/green.jpg"));
	g.DrawImage(&im, 0, 0, rect.right - rect.left, rect.bottom - rect.top);
}

LRESULT CMainDlg::OnCancel(WORD /*wNotifyCode*/, WORD wID, HWND /*hWndCtl*/, BOOL& /*bHandled*/)
{
	Gdiplus::GdiplusShutdown(token);
	EndDialog(wID);
	return 0;
}