bmpdialog.cpp

visual c++ 实例编程

// BmpDialog.cpp : implementation file
//

#include "stdafx.h"
#include "BmpDlg.h"
#include "BmpDialog.h"

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

HBITMAP CBmpDialog::hpreview = NULL;
BOOL CBmpDialog::m_showpreview = TRUE;

// Proprietary Hook function for open dialog

UINT APIENTRY OFNHookProc( HWND hdlg, UINT uiMsg, WPARAM wParam, LPARAM lParam )
{
	LPDRAWITEMSTRUCT lpdis;
	BITMAP bm;
	LPNMHDR pnmh;
	char filename[1024],str[255];
	int height,height2,width,width2;
	NMHDR nmh;
    
    switch (uiMsg)
    {
        case WM_COMMAND:
            if (LOWORD(wParam) == IDC_SHOWPREVIEW)
            {
                CBmpDialog::m_showpreview = IsDlgButtonChecked(hdlg,IDC_SHOWPREVIEW);
                if (!CBmpDialog::m_showpreview)
                {                    
                    if (CBmpDialog::hpreview)
                        DeleteObject(CBmpDialog::hpreview);
                    CBmpDialog::hpreview = NULL;
                    HWND wnd = GetDlgItem(hdlg,IDC_PREVIEWBTN);
                    InvalidateRect(wnd,NULL,TRUE);    
                    SetDlgItemText(hdlg,IDC_WIDTH,"");
                    SetDlgItemText(hdlg,IDC_HEIGHT,"");
                    SetDlgItemText(hdlg,IDC_DEPTH,"");
                    SetDlgItemText(hdlg,IDC_FSIZE,"");
                }
                else
                {
                    nmh.code = CDN_SELCHANGE;
                    OFNHookProc(hdlg, WM_NOTIFY, 0, (LPARAM)&nmh);
                }
            }
            break;
        case WM_DRAWITEM:
            if (CBmpDialog::hpreview)
            {
                lpdis = (LPDRAWITEMSTRUCT)lParam;
                GetObject(CBmpDialog::hpreview,sizeof(BITMAP),&bm);
                CPoint size(bm.bmWidth,bm.bmHeight);                  
                HDC dcmem = CreateCompatibleDC(lpdis->hDC);
                HBITMAP old = (HBITMAP)SelectObject(dcmem,CBmpDialog::hpreview);
                if (bm.bmWidth > bm.bmHeight)
                {
                    height = lpdis->rcItem.bottom - lpdis->rcItem.top;
                    float ratio = (float)bm.bmHeight/(float)bm.bmWidth;
                    lpdis->rcItem.bottom  = (long) (lpdis->rcItem.top + (lpdis->rcItem.right-lpdis->rcItem.left)*ratio);
                    height2 = (height - (lpdis->rcItem.bottom - lpdis->rcItem.top))/2;
                    lpdis->rcItem.top += height2;
                    lpdis->rcItem.bottom += height2;
                }
                else
                {
                    width = lpdis->rcItem.right - lpdis->rcItem.left;
                    float ratio = (float)bm.bmWidth/(float)bm.bmHeight;
                    lpdis->rcItem.right  = (long) (lpdis->rcItem.left + (lpdis->rcItem.bottom-lpdis->rcItem.top)*ratio);
                    width2 = (width - (lpdis->rcItem.right - lpdis->rcItem.left))/2;
                    lpdis->rcItem.left += width2;
                    lpdis->rcItem.right += width2;

                }
                StretchBlt(lpdis->hDC,lpdis->rcItem.left,lpdis->rcItem.top,lpdis->rcItem.right-lpdis->rcItem.left,lpdis->rcItem.bottom-lpdis->rcItem.top,dcmem,0,0,bm.bmWidth,bm.bmHeight,SRCCOPY);
                SelectObject(dcmem,old);
                DeleteDC(dcmem);
            }
            break;

        case WM_NOTIFY:      
            pnmh = (LPNMHDR) lParam;

            if (pnmh->code == CDN_FILEOK)
            {
                if (CBmpDialog::hpreview)
                        DeleteObject(CBmpDialog::hpreview);

                _AFX_THREAD_STATE* pThreadState = AfxGetThreadState();
	            pThreadState->m_pAlternateWndInit = NULL;
                return 0;
            }

            if (pnmh->code ==  CDN_INITDONE)
            {
               if (CBmpDialog::hpreview)
                    DeleteObject(CBmpDialog::hpreview);
                CheckDlgButton(hdlg,IDC_SHOWPREVIEW,CBmpDialog::m_showpreview);
                return 0;
            }

            if (pnmh->code == CDN_SELCHANGE)
            {
                if (!IsDlgButtonChecked(hdlg,IDC_SHOWPREVIEW))
                {                
                    if (CBmpDialog::hpreview)
                        DeleteObject(CBmpDialog::hpreview);
                    CBmpDialog::hpreview = NULL;
                    return 0;
                }
                
                SendMessage(GetParent(hdlg),CDM_GETFILEPATH ,1024,(LPARAM)filename);
                if (CBmpDialog::hpreview)
                    DeleteObject(CBmpDialog::hpreview);
                CBmpDialog::hpreview = (HBITMAP)LoadImage(AfxGetInstanceHandle(),filename,IMAGE_BITMAP,0,0,LR_LOADFROMFILE|LR_CREATEDIBSECTION);
                HWND wnd = GetDlgItem(hdlg,IDC_PREVIEWBTN);
                InvalidateRect(wnd,NULL,TRUE);

                if (CBmpDialog::hpreview)
                {
                    GetObject(CBmpDialog::hpreview,sizeof(BITMAP),&bm);       
                    wsprintf(str,"宽度: %d 像素",bm.bmWidth);
                    SetDlgItemText(hdlg,IDC_WIDTH,str);
                    wsprintf(str,"高度: %d 像素",bm.bmHeight);
                    SetDlgItemText(hdlg,IDC_HEIGHT,str);
                    
                    switch (bm.bmBitsPixel)
                    {
                        case 1:
                            SetDlgItemText(hdlg,IDC_DEPTH,"颜色: 单色位图");
                            break;
                        case 4:
                            SetDlgItemText(hdlg,IDC_DEPTH,"颜色: 16色位图");
                            break;
                        case 8:
                            SetDlgItemText(hdlg,IDC_DEPTH,"颜色: 256色位图");
                            break;
                        case 16:
                            SetDlgItemText(hdlg,IDC_DEPTH,"颜色: 65,536色位图");
                            break;
                        case 24:
                            SetDlgItemText(hdlg,IDC_DEPTH,"颜色: 24位真彩色位图");
                            break;
                        default:
                            SetDlgItemText(hdlg,IDC_DEPTH,"");
                    }
                    OFSTRUCT o;
                    HFILE f = OpenFile(filename,&o,OF_READ);
                    wsprintf(str,"大小: %ld 千字节",GetFileSize((HANDLE)f,NULL)/1024+1);
                    SetDlgItemText(hdlg,IDC_FSIZE,str);
                    _lclose(f);
                }
                else
                {
                    SetDlgItemText(hdlg,IDC_WIDTH,"");
                    SetDlgItemText(hdlg,IDC_HEIGHT,"");
                    SetDlgItemText(hdlg,IDC_DEPTH,"");
                    SetDlgItemText(hdlg,IDC_FSIZE,"");
                }
            }
    }
    return 0;
}

/////////////////////////////////////////////////////////////////////////////
// CBmpDialog

IMPLEMENT_DYNAMIC(CBmpDialog, CFileDialog)

CBmpDialog::CBmpDialog(BOOL bOpenFileDialog, LPCTSTR lpszDefExt, LPCTSTR lpszFileName,
		DWORD dwFlags, LPCTSTR lpszFilter, CWnd* pParentWnd) :
		CFileDialog(bOpenFileDialog, lpszDefExt, lpszFileName, dwFlags, lpszFilter, pParentWnd)
{
	m_ofn.lpstrFilter = "Bitmaps (*.bmp)\0*.bmp\0"\
                        "All Files (*.*)\0*.*\0\0";                            

    m_ofn.Flags |= (OFN_HIDEREADONLY |OFN_ENABLEHOOK| OFN_EXPLORER  |OFN_ENABLETEMPLATE);

    m_ofn.hInstance = AfxGetInstanceHandle();
    m_ofn.lpTemplateName = MAKEINTRESOURCE(IDC_PREVIEW);
    m_ofn.lpfnHook = OFNHookProc;
}


BEGIN_MESSAGE_MAP(CBmpDialog, CFileDialog)
	//{{AFX_MSG_MAP(CBmpDialog)
		// NOTE - the ClassWizard will add and remove mapping macros here.
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()