modeless dialog.

     First of all, I must announce that the main ideas of this paper are from Programming Microsoft Visual C++ Fifth Edition.

 

 

In order to demostrate the modeless dialog. Here I take the following steps:

 

1   Setup a single document MFC project.

 

2   Add a dialog (here we must make the dialog visiable), Here I do nothing to the dialog.   The Create a new Dialog class for this dialog only has a pointer to its parent and also a User message to communicate with its parent. See the following segment for more information:

 

#ifndef __MODELESSDLG__ #define __MODELESSDLG__ #include "resource.h" // CModelessDlg.h : header file // ///////////////////////////////////////////////////////////////////////////// // CModelessDlg dialog #define WM_TOPARENT WM_USER + 5 class CModelessDlg : public CDialog { private: CView* m_pView; public: CModelessDlg(CView* pView); BOOL Create(); // Construction public: CModelessDlg(CWnd* pParent = NULL); // standard constructor // Dialog Data //{​{AFX_DATA(CModelessDlg) enum { IDD = IDD_MODELESS }; //}}AFX_DATA // Overrides // ClassWizard generated virtual function overrides //{​{AFX_VIRTUAL(CModelessDlg) protected: virtual void DoDataExchange(CDataExchange* pDX); // DDX/DDV support //}}AFX_VIRTUAL // Implementation protected: // Generated message map functions //{​{AFX_MSG(CModelessDlg) virtual void OnCancel(); virtual void OnOK(); //}}AFX_MSG DECLARE_MESSAGE_MAP() }; #endif  

 

 

#include "stdafx.h" #include "CModelessDlg.h" #include "modeless.h" #ifdef _DEBUG #define new DEBUG_NEW #undef THIS_FILE static char THIS_FILE[] = __FILE__; #endif ///////////////////////////////////////////////////////////////////////////// // CModelessDlg dialog CModelessDlg::CModelessDlg(CWnd* pParent /*=NULL*/) : CDialog(CModelessDlg::IDD, pParent) { //{​{AFX_DATA_INIT(CModelessDlg) //}}AFX_DATA_INIT m_pView = NULL; } CModelessDlg::CModelessDlg(CView* pView) // modeless constructor { m_pView = pView; } BOOL CModelessDlg::Create() { return CDialog::Create(CModelessDlg::IDD); } void CModelessDlg::DoDataExchange(CDataExchange* pDX) { CDialog::DoDataExchange(pDX); //{​{AFX_DATA_MAP(CModelessDlg) //}}AFX_DATA_MAP } BEGIN_MESSAGE_MAP(CModelessDlg, CDialog) //{​{AFX_MSG_MAP(CModelessDlg) //}}AFX_MSG_MAP END_MESSAGE_MAP() ///////////////////////////////////////////////////////////////////////////// // CModelessDlg message handlers void CModelessDlg::OnCancel() // not really a message handler { if (m_pView != NULL) { // modeless case -- do not call base class OnCancel m_pView->PostMessage(WM_TOPARENT, IDCANCEL); } else { CDialog::OnCancel(); // modal case } } void CModelessDlg::OnOK() // not really a message handler { if (m_pView != NULL) { // modeless case -- do not call base class OnOK //UpdateData(TRUE); m_pView->PostMessage(WM_TOPARENT, IDOK); } else { CDialog::OnOK(); // modal case } }

 

3 In the View class header, I add a CModelessDlg member, its forward declaration and the initialization of the class.

 

 

// forward declaration
class CModelessDlg;

 

 

private:
    CModelessDlg* m_pDlg;

 

 

CmodelessView::CmodelessView()
{
    // TODO: add construction code here
    m_pDlg=new CModelessDlg(this);
}

CmodelessView::~CmodelessView()
{
    if(m_pDlg)
        delete m_pDlg;
}

 

4 Add a menu item named "Find" to the edit menu. and map its on command like this.

 

//header file // Generated message map functions protected: afx_msg LRESULT OnToParent(WPARAM wParam, LPARAM lParam); DECLARE_MESSAGE_MAP() public: afx_msg void OnEditFind32771(); // cpp file BEGIN_MESSAGE_MAP(CmodelessView, CView) ON_COMMAND(ID_EDIT_FIND32771, &CmodelessView::OnEditFind32771) ON_MESSAGE(WM_TOPARENT, OnToParent) END_MESSAGE_MAP() void CmodelessView::OnEditFind32771() { // TODO: Add your command handler code here // creates the dialog if not created already if (m_pDlg->GetSafeHwnd() == 0) { m_pDlg->Create(); // displays the dialog window } }

 

 

5 The above operation we can implement a modeless dialog now. but i also forward the dialog message to its parent

    for more processing, The ToParent message.