include/wx/msw/private/dc.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/msw/private/dc.h
   3 // Purpose:     private wxMSW helpers for working with HDCs
   4 // Author:      Vadim Zeitlin
   5 // Created:     2009-06-16 (extracted from src/msw/dc.cpp)
   6 // Copyright:   (c) 2009 Vadim Zeitlin <vadim@wxwidgets.org>
   7 // Licence:     wxWindows licence
   8 ///////////////////////////////////////////////////////////////////////////////
   9
  10 #ifndef _MSW_PRIVATE_DC_H_
  11 #define _MSW_PRIVATE_DC_H_
  12
  13 #include "wx/msw/dc.h"
  14 #include "wx/msw/wrapwin.h"
  15
  16 namespace wxMSWImpl
  17 {
  18
  19 // various classes to change some DC property temporarily
  20
  21 // text background and foreground colours
  22 class wxTextColoursChanger
  23 {
  24 public:
  25     wxTextColoursChanger(HDC hdc, const wxMSWDCImpl& dc)
  26         : m_hdc(hdc)
  27     {
  28         Change(dc.GetTextForeground(), dc.GetTextBackground());
  29     }
  30
  31     wxTextColoursChanger(HDC hdc, const wxColour& colFg, const wxColour& colBg)
  32         : m_hdc(hdc)
  33     {
  34         Change(colFg, colBg);
  35     }
  36
  37     wxTextColoursChanger(HDC hdc, COLORREF colFg, COLORREF colBg)
  38         : m_hdc(hdc)
  39     {
  40         Change(colFg, colBg);
  41     }
  42
  43     ~wxTextColoursChanger()
  44     {
  45         if ( m_oldColFg != CLR_INVALID )
  46             ::SetTextColor(m_hdc, m_oldColFg);
  47         if ( m_oldColBg != CLR_INVALID )
  48             ::SetBkColor(m_hdc, m_oldColBg);
  49     }
  50
  51 protected:
  52     // this ctor doesn't change mode immediately, call Change() later to do it
  53     // only if needed
  54     wxTextColoursChanger(HDC hdc)
  55         : m_hdc(hdc)
  56     {
  57         m_oldColFg =
  58         m_oldColBg = CLR_INVALID;
  59     }
  60
  61     void Change(const wxColour& colFg, const wxColour& colBg)
  62     {
  63         Change(colFg.IsOk() ? colFg.GetPixel() : CLR_INVALID,
  64                colBg.IsOk() ? colBg.GetPixel() : CLR_INVALID);
  65     }
  66
  67     void Change(COLORREF colFg, COLORREF colBg)
  68     {
  69         if ( colFg != CLR_INVALID )
  70         {
  71             m_oldColFg = ::SetTextColor(m_hdc, colFg);
  72             if ( m_oldColFg == CLR_INVALID )
  73             {
  74                 wxLogLastError(wxT("SetTextColor"));
  75             }
  76         }
  77         else
  78         {
  79             m_oldColFg = CLR_INVALID;
  80         }
  81
  82         if ( colBg != CLR_INVALID )
  83         {
  84             m_oldColBg = ::SetBkColor(m_hdc, colBg);
  85             if ( m_oldColBg == CLR_INVALID )
  86             {
  87                 wxLogLastError(wxT("SetBkColor"));
  88             }
  89         }
  90         else
  91         {
  92             m_oldColBg = CLR_INVALID;
  93         }
  94     }
  95
  96 private:
  97     const HDC m_hdc;
  98     COLORREF m_oldColFg,
  99              m_oldColBg;
 100
 101     wxDECLARE_NO_COPY_CLASS(wxTextColoursChanger);
 102 };
 103
 104 // background mode
 105 class wxBkModeChanger
 106 {
 107 public:
 108     // set background mode to opaque if mode != wxBRUSHSTYLE_TRANSPARENT
 109     wxBkModeChanger(HDC hdc, int mode)
 110         : m_hdc(hdc)
 111     {
 112         Change(mode);
 113     }
 114
 115     ~wxBkModeChanger()
 116     {
 117         if ( m_oldMode )
 118             ::SetBkMode(m_hdc, m_oldMode);
 119     }
 120
 121 protected:
 122     // this ctor doesn't change mode immediately, call Change() later to do it
 123     // only if needed
 124     wxBkModeChanger(HDC hdc) : m_hdc(hdc) { m_oldMode = 0; }
 125
 126     void Change(int mode)
 127     {
 128         m_oldMode = ::SetBkMode(m_hdc, mode == wxBRUSHSTYLE_TRANSPARENT
 129                                         ? TRANSPARENT
 130                                         : OPAQUE);
 131         if ( !m_oldMode )
 132         {
 133             wxLogLastError(wxT("SetBkMode"));
 134         }
 135     }
 136
 137 private:
 138     const HDC m_hdc;
 139     int m_oldMode;
 140
 141     wxDECLARE_NO_COPY_CLASS(wxBkModeChanger);
 142 };
 143
 144 } // namespace wxMSWImpl
 145
 146 #endif // _MSW_PRIVATE_DC_H_
 147