scrolldlg.cpp

《Windows CE 6.0开发者参考》（《Programming Windows Embedded CE 6.0 Developer Reference》）第四版书中的源代码

//======================================================================
// ScrollDlg - Scrollable dialog box window code
//
// Written for the book Programming Windows CE
// Copyright (C) 2007 Douglas Boling
//======================================================================
#include <windows.h>                 // For all that Windows stuff
#include <commctrl.h>                // Common Control includes
#include <prsht.h>                   // Property sheet includes
#include "DlgDemo.h"                 // Program-specific stuff

// Structure labeling the button control WM_COMMAND notifications
NOTELABELS nlBtn[] = {{TEXT ("BN_CLICKED "),      BN_CLICKED },
                      {TEXT ("BN_PAINT   "),      BN_PAINT   },
                      {TEXT ("BN_SETFOCUS "),     BN_SETFOCUS},
                      {TEXT ("BN_KILLFOCUS"),     BN_KILLFOCUS}
};
// Scroll position of dialog
int nVPos = 0;
//======================================================================
// ScrollableDlgProc - Scrollable dialog box procedure
//
BOOL CALLBACK ScrollableDlgProc (HWND hWnd, UINT wMsg, WPARAM wParam,
                                 LPARAM lParam) {
    switch (wMsg) {
        case WM_INITDIALOG:
            return TRUE;
        //
        // Reflect WM_COMMAND messages to main window.
        //
        case WM_COMMAND:
            PrintCmdMessage (wParam, lParam, nlBtn, sizeof(nlBtn));
            // Close dialog for OK or Cancel
            switch (LOWORD (wParam)) {
                case IDOK:
                case IDCANCEL:
                    EndDialog (hWnd, 0);
                    return TRUE;
            }
            return TRUE;
        //
        // Reflect notify message.
        //
        case WM_NOTIFY:
            PrintNotMessage (lParam, NULL, 0);
            return FALSE;  // Return false to force default processing.

        case WM_VSCROLL:
            {
                int nNewPos = nVPos;
                int nLinesPerPage = 5;

                switch (LOWORD (wParam)) {
                case SB_LINEUP:
                    nNewPos -= 1;
                    break;

                case SB_LINEDOWN:
                    nNewPos += 1;
                    break;

                case SB_PAGEUP:
                    nNewPos -= nLinesPerPage;
                    break;

                case SB_PAGEDOWN:
                    nNewPos += nLinesPerPage;
                    break;

                case SB_THUMBTRACK:
                case SB_THUMBPOSITION:
                    nNewPos = HIWORD (wParam);
                    break;
                }
                
                // If scroll position changed, Scroll the window and 
                // update scrollbar
                if (nVPos != nNewPos) {
                    ScrollWindowEx (hWnd, 0, nVPos - nNewPos, NULL, NULL,
                          NULL, NULL, SW_INVALIDATE | SW_SCROLLCHILDREN);

                    SCROLLINFO si;
                    nVPos = nNewPos;
                    si.cbSize = sizeof (si);
                    si.nPos = nVPos;
                    si.fMask = SIF_POS;
                    SetScrollInfo (hWnd, SB_VERT, &si, TRUE);
                }
            }
            break;
    }
    return FALSE;
}