WM_IDLEUPDATECMDUI与CView

CFrameWnd貌似会向其CView子窗口(从CWnd继承的子窗口也适用)发生此消息, 子窗口可以响应该消息来更新一些按钮控件的状态. ex:

#pragma once
// CWelcomeView

class CWelcomeWnd : public CWnd
{
public:
    CWelcomeWnd();
    virtual ~CWelcomeWnd();

protected:
    DECLARE_MESSAGE_MAP()

    afx_msg  void OnIdleUpdateCmdUI();  

};

// WelcomeView.cpp : 实现文件
//

#include "stdafx.h"
#include "WelcomeView.h"
#include "afxpriv.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

// CWelcomeView

CWelcomeView::CWelcomeView()
{

}

CWelcomeView::~CWelcomeView()
{
}

BEGIN_MESSAGE_MAP(CWelcomeView, CWnd)
    ON_MESSAGE_VOID(WM_IDLEUPDATECMDUI, OnIdleUpdateCmdUI)
END_MESSAGE_MAP()

// CWelcomeView 消息处理程序

afx_msg void CWelcomeView::OnIdleUpdateCmdUI()
{
    BOOL bEnabled = FALSE;

    // 树形控件弹出菜单

    // 导入导出
    bEnabled = (m_nCurrTag == TAG_SIM1 ||
                m_nCurrTag == TAG_SIM2 ||
                m_nCurrTag == TAG_ME);
    m_wndDropBtnImpExp.EnableCommand(IDC_IMPEXP,    bEnabled);
    m_wndDropBtnImpExp.EnableCommand(IDC_IMPCSV,    bEnabled);
    m_wndDropBtnImpExp.EnableCommand(IDC_IMPVCARD,    bEnabled);
    m_wndDropBtnImpExp.EnableCommand(IDC_EXPCSV,    bEnabled);
    m_wndDropBtnImpExp.EnableCommand(IDC_EXPVCARD,    bEnabled);

    // 复制粘贴
    bEnabled = (m_nCurrTag == TAG_SIM1 ||
                m_nCurrTag == TAG_SIM2 ||
                m_nCurrTag == TAG_ME   ||
                m_nCurrTag == TAG_LOCAL);
    bEnabled &= (m_wndPbList.GetSelectedCount() > 0);
    m_wndDropBtnCopySave.EnableCommand(IDC_COPY1, bEnabled);
    m_wndDropBtnCopySave.EnableCommand(IDC_CUT1, bEnabled);

    bEnabled = (m_nCurrTag == TAG_SIM1 ||
        m_nCurrTag == TAG_SIM2 ||
        m_nCurrTag == TAG_ME   ||
        m_nCurrTag == TAG_LOCAL);
    bEnabled &= (m_clipboard.size() > 0);
    m_wndDropBtnCopySave.EnableCommand(IDC_PASTE1, bEnabled);

    // 删除
    bEnabled = (m_wndPbList.GetSelectedCount() > 0);
    m_wndBtnDelete.EnableWindow(bEnabled);

    // 同步
    bEnabled = (m_nCurrTag == TAG_SIM1 ||
        m_nCurrTag == TAG_SIM2 ||
        m_nCurrTag == TAG_ME);
    m_wndBtnSync.EnableWindow(bEnabled);

    // 刷新
    //bEnabled = (m_nCurrTag == TAG_SIM1 ||
    //    m_nCurrTag == TAG_SIM2 ||
    //    m_nCurrTag == TAG_ME);

    // 添加
    bEnabled = (m_nCurrTag == TAG_SIM1 ||
        m_nCurrTag == TAG_SIM2 ||
        m_nCurrTag == TAG_ME);
    m_wndPbList.EnableTopButton(TOP_COMMAND_ADD, bEnabled);

}