Introduction
I wanted to draw a button which is transparent to its back ground image and hence had gone through several articles about button styles - transparent buttons. They were all very tedious tasks of making a button transparent - erase button back ground, draw picture etc. I found an easy method. The idea behind this is, draw a bitmap picture on the dialog box. Draw the same bitmap on the button from the location LeftTop of the button. Button is not visible like a button unless mouse cursor is moved on it. Therefore I'll add two icons on the button.
//I have implemented two important functions - //SetTransparent() and PaintBG(CDC *pDC, CRect rc) //SetTranparent function loads bitmap from the resource and //creates an handle to CDC - m_hHdc. void CBut::SetTransparent() { HBITMAP m_hBmp = ::LoadBitmap(::AfxGetInstanceHandle(), MAKEINTRESOURCE(IDB_BITMAP6)); m_hHdc = ::CreateCompatibleDC(NULL); ::SelectObject(m_hHdc, m_hBmp); } //PaintBG fnction is called in DrawItem function which draws //bitmap on the button from the location left-top of the button. void CBut::PaintBG(CDC *pDC, CRect rc) { CRect rect; GetWindowRect(rect); GetParent()->ScreenToClient(rect); if(m_hHdc!=NULL) ::BitBlt(pDC->m_hDC, rc.left, rc.top, rect.Width(), rect.Height(), m_hHdc, rect.left, rect.top, SRCCOPY); }
How to use the source files
Draw bitmap on the dialog box in CPaint function of your CDialog derived class. Check the 'OwnerDraw' property of the button. Create a variable of type CButtonStyle in dialog class. Don't forget to include ButtonStyle.h file name in the same class.
Collapse
void CButtonStyleDlg::OnPaint() { if (IsIconic()) { CPaintDC dc(this); // device context for painting .................... ............ } else { CPaintDC dc(this); CRect rect; GetClientRect(&rect); //ScreenToClient(rect); BITMAP bmp; HBITMAP hBmp = ::LoadBitmap(::AfxGetInstanceHandle(), MAKEINTRESOURCE(IDB_BITMAP1)); ::GetObject(hBmp, sizeof(bmp), &bmp); HDC hDC = ::CreateCompatibleDC(NULL); SelectObject(hDC, hBmp); //Note: Do not use StretchBlt function. ::BitBlt(dc.m_hDC, 0, 0, rect.Width(), rect.Height(), hDC, 0, 0, SRCCOPY); CDialog::OnPaint(); } } //Set button properties in OnInitDialog() function of CDialog derived class BOOL CButtonStyleDlg::OnInitDialog() { CDialog::OnInitDialog(); ....................... ......... .................. // Set the icon for this dialog. The framework does this automatically // when the application's main window is not a dialog SetIcon(m_hIcon, TRUE); // Set big icon SetIcon(m_hIcon, FALSE); // Set small icon // TODO: Add extra initialization here m_btnButton1.SetTransparent(); m_btnButton1.SetTextColor(RGB(0,220,0), RGB(0,255,0)); m_btnButton1.SetIcons(IDI_ICON4, IDI_ICON4); m_btnButton1.FontStyle("MS Sans Serif"); m_btnOK.SetTransparent(); m_btnOK.SetTextColor(RGB(0,220, 0), RGB(0,255,0)); m_btnOK.SetIcons(IDI_ICON2, IDI_ICON2); m_btnOK.FontStyle("MS Sans Serif"); m_btnExit.SetTransparent(); m_btnExit.SetTextColor(RGB(0,220,0), RGB(0,255,0)); m_btnExit.SetIcons(IDI_ICON1, IDI_ICON1); m_btnExit.FontStyle("MS Sans Serif"); m_btnClick.SetTransparent(); m_btnClick.SetTextColor(RGB(0,220,0), RGB(0,255,0)); m_btnClick.SetIcons(IDI_ICON3, IDI_ICON5); m_btnClick.FontStyle("MS Sans Serif"); return TRUE; // return TRUE unless you set the focus to a control }