Windows NT Systems Programming

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Version 4

Some Steps in converting home grown dialogs for message folders to one using CDialog

Also used the visual editing tool for menus and dialog boxes.

Creating Project

• Open VC++
• Select New to get open project dialog
  • select win32
  • name it
  • choose directory
  • OK
• Add files from home grown version (make copies)
• change setting to use shared MFC DLLs

Building the Menu using resource editor

• Insert/Resource to get dialog box
• choose menu
• click to add menu items
  • double click to change properties such as ID (if you want)
• save resource script
• add this file to your project

Building a Dialog Box

• Insert/Resource
• Select plain (top level) dialog
• build it using visual editing tools

NOTE: you get OK and Cancel for free.

Connecting CDialog

• New/Header named CFolderDlg
• Derive a new class from CDialog

// FolderDlg.h: interface for the CFolderDlg class.
//
//////////////////////////////////////////////////////////////////////
#ifndef H_FOLDERDLG
#define H_FOLDERDLG
#include <afxwin.h>
#include "resource.h"

class CFolderDlg : public CDialog  
{
public:
	CFolderDlg(CWnd* pParentWnd = NULL) :
	  CDialog(IDD_FOLDER, pParentWnd) {}
	virtual BOOL OnInitDialog();
	CString m_folderName;
protected:
	virtual void OnOK();

	afx_msg void OnFolderSelection();
	afx_msg void OnFolderDblClk();
	DECLARE_MESSAGE_MAP()	// set up message map handling
	
};
#endif

Implementation

// FolderDlg.cpp: implementation of the CFolderDlg class.
//
//////////////////////////////////////////////////////////////////////

#include "FolderDlg.h"
#include "main.h"

extern CMsgFolderApp msgFolderApp; 

// Message map - maps message IDs to their handlers
BEGIN_MESSAGE_MAP( CFolderDlg, CDialog )
	ON_LBN_SELCHANGE(IDC_FOLDER_LIST,OnFolderSelection)
	ON_LBN_DBLCLK(IDC_FOLDER_LIST,OnFolderDblClk)
END_MESSAGE_MAP()

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////


BOOL CFolderDlg::OnInitDialog()
{
	CDialog::OnInitDialog();
	// build list of message folders in current directory
	HANDLE folder;
	WIN32_FIND_DATA findData;
	
	folder = FindFirstFile("*", &findData);
	while( folder != INVALID_HANDLE_VALUE) {
		if(findData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
			// assume all directories are folders
			((CListBox*)GetDlgItem(IDC_FOLDER_LIST))->AddString(findData.cFileName);
		}
		if(!FindNextFile(folder, &findData))
			break;
	}
	FindClose(folder);

	return TRUE;
}
void CFolderDlg::OnOK()
{
	
	((CEdit*)GetDlgItem(IDC_SELECTION))->GetWindowText(m_folderName);
	if(msgFolderApp.msgFolder.OpenMsgFolder(m_folderName))
		CDialog::OnOK();	// clean up and return successfully
	else {
		MessageBox("Message Folder Corrupted!\n Try another folder", "ERROR");
	}
	
}

void CFolderDlg::OnFolderSelection()
{
	CString selection;
	int nIndex = ((CListBox*)GetDlgItem(IDC_FOLDER_LIST))->GetCurSel();
	if (nIndex != LB_ERR) {
		((CListBox*)GetDlgItem(IDC_FOLDER_LIST))->GetText(nIndex,selection);
		((CEdit*)GetDlgItem(IDC_SELECTION))->SetWindowText(selection);
	}
}

void CFolderDlg::OnFolderDblClk()
{
	CString selection;

	int nIndex = ((CListBox*)GetDlgItem(IDC_FOLDER_LIST))->GetCurSel();
	if (nIndex != LB_ERR) {
		((CListBox*)GetDlgItem(IDC_FOLDER_LIST))->GetText(nIndex,selection);
		((CEdit*)GetDlgItem(IDC_SELECTION))->SetWindowText(selection);
		OnOK();
	}
}

The (almost) Final Version 4

Project is here.

Solution consists of:

• 16 files
• 9 Classes
• 5 resources
  • 1 menu
  • 3 dialogs
    • Selecting Folder
    • Selecting Message in folder
    • Editing Message
  • 1 accelerator

in CMsgFolder class:

• Changed name of "PostMsg" function  to "NewMsg"
• Added "UpdateMsg" function which replaces an existing message with an edited version.

Program Flow

• Using main menu, select Open Folder Dialog
• Pick an existing or new folder name
• This calls OpenMsgFolder function of CMsgFolder on public member of main application object.
  (so message folder has global visibility -
  • what else if global visible?
  • can you access members of CMainWindow globally?
  • how?
• This is the communications between this dialog and the application (and is reflected in the title bar)

• Using main menu, select Edit Message (dialog)
• User can select by topic or by NEW button.
• New button calls OnOK (to get proper return from DoModal dialog
• passes MsgId (position in list) back to calling program in public data member of dialog class
• Creates message object, if not new, initialzes from file.
• Calls Message Edit object, passing pointer to message in public data member of edit dialog object.
• After editing, calls appropriate CMsgFolder function to store in folder.

Copyright chris wild 1997.
For problems or questions regarding this web contact [Dr. Wild].
Last updated: October 01, 1997.