You should be able to use this demo as a skeleton application for your own project.

A standard CDialog EXE application was created with the wizard and apart from the standard supplied code, the following functions were overridden.

void OnClose() Used to clean up some resources on exit.
void OnPaint() Used to paint the bimap into the region.
void OnSize(UINT nType, int cx, int cy) Used to create the region and position and resize the dialog.
void OnLButtonDown(UINT nFlags, CPoint point) To allow the dialog to be dragged by clicking anywhere.

A button was created to allow the user to close the dialog. A timer was created to demonstrate auto closing after a period of time.

The image is a normal bmp file that is loaded by the app and used to paint the dialog. TRANSPARENTCOLOR is defined in the dialog class header as bright purple (RGB(255, 0, 255), but this could be changed to any colour you like.

The dialog window is auto sized to the size of the loaded bitmap then a region created based on the transparent colour. The dialog is then positioned in the centre of the current screen. This was done as an example for those who want to use this application as a splash windows.

#define TRANSPARENTCOLOR RGB(255, 0, 255);

BITMAP  m_Bitmap;                // Struct to hold info about the bitmap
HBITMAP m_hBitmap;                // Handle of the bitmap

void CTransparentDialogDlg::OnClose()
        // TODO: Add your message handler code here and/or call default
        DeleteObject(m_hBitmap);        //not really need but what the heck.

void CTransparentDialogDlg::OnPaint()
        // device context for painting
        CPaintDC dc(this);
        //Create a memory DC
        HDC hMemDC = ::CreateCompatibleDC(NULL);
        //Select the bitmap in the memory dc.
        SelectObject(hMemDC, m_hBitmap);
        //Copy the memory dc into the screen dc
        ::BitBlt(dc.m_hDC, 0, 0, m_Bitmap.bmWidth, m_Bitmap.bmHeight, hMemDC, 0, 0, SRCCOPY);
        //Delete the memory DC and the bitmap

void CTransparentDialogDlg::OnSize(UINT nType, int cx, int cy)
        CDialog::OnSize(nType, cx, cy);
        // Load the image
        m_hBitmap = (HBITMAP)LoadImage(GetModuleHandle(NULL), "Image.bmp", IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE);
        if (m_hBitmap == NULL)
                MessageBox("Error loading bitmap");
        //Get information about the bitmap..
        GetObject(m_hBitmap, sizeof(m_Bitmap), &m_Bitmap);        // Get info about the bitmap
        // Put the bitmap into a memory device context
        CPaintDC dc(this);
        //get a memory dc object
        CDC dcMem;
        //create a compatible dc
        dcMem.CreateCompatibleDC(&dc);        // Select the bitmap into the in-memory DC
        //Select the bitmap into the dc
        CBitmap* pOldBitmap = dcMem.SelectObject(CBitmap::FromHandle(m_hBitmap));
        //Create a couple of region objects.
        CRgn crRgn, crRgnTmp;
        //create an empty region
        crRgn.CreateRectRgn(0, 0, 0, 0);
        //Create a region from a bitmap with transparency colour of Purple
        COLORREF crTransparent = TRANSPARENTCOLOR;        
        int iX = 0;
        for (int iY = 0; iY < m_Bitmap.bmHeight; iY++)
                        //skip over transparent pixels at start of lines.
                        while (iX <= m_Bitmap.bmWidth && dcMem.GetPixel(iX, iY) == crTransparent)
                        //remember this pixel
                        int iLeftX = iX;
                        //now find first non transparent pixel
                        while (iX <= m_Bitmap.bmWidth && dcMem.GetPixel(iX, iY) != crTransparent)
                        //create a temp region on this info
                        crRgnTmp.CreateRectRgn(iLeftX, iY, iX, iY+1);
                        //combine into main region.
                        crRgn.CombineRgn(&crRgn, &crRgnTmp, RGN_OR);
                        //delete the temp region for next pass (otherwise you'll get an ASSERT)
                }while(iX < m_Bitmap.bmWidth);
                iX = 0;
        //Centre it on current desktop
        SetWindowRgn(crRgn, TRUE);
        iX = (GetSystemMetrics(SM_CXSCREEN)) / 2 - (m_Bitmap.bmWidth / 2);
        iY = (GetSystemMetrics(SM_CYSCREEN)) / 2 - (m_Bitmap.bmHeight / 2);
        SetWindowPos(&wndTopMost, iX, iY, m_Bitmap.bmWidth, m_Bitmap.bmHeight, NULL);

        // Free resources.
        dcMem.SelectObject(pOldBitmap);        // Put the original bitmap back (prevents memory leaks)

void CTransparentDialogDlg::OnLButtonDown(UINT nFlags, CPoint point)
        // TODO: Add your message handler code here and/or call default
        PostMessage( WM_NCLBUTTONDOWN, HTCAPTION, MAKELPARAM( point.x, point.y));
        CDialog::OnLButtonDown(nFlags, point);

facebook posting twit

  • DirectShow – NULL Rendering Example
  • Broadcast를 이용한 Application 종료
  • IE Control을 사용하여 만든 어플리케이션에서 javascript로 어플리케이션에 정의된 함수 호출하는 방법
  • 윈도우 옮기는 API – SetWindowPos
  • GDI+ Programming 방법
  • 불투명 윈도우 만들기
  • 비트맵을 배경으로 뿌리고 그 위에 컨트롤 올리는 방법
  • BITMAP 오브젝트에서 가로,세로 크기 알아내기
  • 듀얼 모니터에서 Focused Monitor의 Rect 알아내기
  • 프로그램에서 버젼(version) 정보 읽어주는 소스
    Tagged on:
  • Leave a Reply