no real changes, just extract private classes from msw/dc.cpp into a private header so that they could be reused from button owner drawing code too

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@61060 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/private/dc.h

@@ -0,0 +1,148 @@
+///////////////////////////////////////////////////////////////////////////////
+// Name:        msw/private/dc.h
+// Purpose:     private wxMSW helpers for working with HDCs
+// Author:      Vadim Zeitlin
+// Created:     2009-06-16 (extracted from src/msw/dc.cpp)
+// RCS-ID:      $Id$
+// Copyright:   (c) 2009 Vadim Zeitlin <vadim@wxwidgets.org>
+// Licence:     wxWindows licence
+///////////////////////////////////////////////////////////////////////////////
+
+#ifndef _MSW_PRIVATE_DC_H_
+#define _MSW_PRIVATE_DC_H_
+
+#include "wx/msw/dc.h"
+#include "wx/msw/wrapwin.h"
+
+namespace wxMSWImpl
+{
+
+// various classes to change some DC property temporarily
+
+// text background and foreground colours
+class wxTextColoursChanger
+{
+public:
+    wxTextColoursChanger(HDC hdc, const wxMSWDCImpl& dc)
+        : m_hdc(hdc)
+    {
+        Change(dc.GetTextForeground(), dc.GetTextBackground());
+    }
+
+    wxTextColoursChanger(HDC hdc, const wxColour& colFg, const wxColour& colBg)
+        : m_hdc(hdc)
+    {
+        Change(colFg, colBg);
+    }
+
+    wxTextColoursChanger(HDC hdc, COLORREF colFg, COLORREF colBg)
+        : m_hdc(hdc)
+    {
+        Change(colFg, colBg);
+    }
+
+    ~wxTextColoursChanger()
+    {
+        if ( m_oldColFg != CLR_INVALID )
+            ::SetTextColor(m_hdc, m_oldColFg);
+        if ( m_oldColBg != CLR_INVALID )
+            ::SetBkColor(m_hdc, m_oldColBg);
+    }
+
+protected:
+    // this ctor doesn't change mode immediately, call Change() later to do it
+    // only if needed
+    wxTextColoursChanger(HDC hdc)
+        : m_hdc(hdc)
+    {
+        m_oldColFg =
+        m_oldColBg = CLR_INVALID;
+    }
+
+    void Change(const wxColour& colFg, const wxColour& colBg)
+    {
+        Change(colFg.IsOk() ? colFg.GetPixel() : CLR_INVALID,
+               colBg.IsOk() ? colBg.GetPixel() : CLR_INVALID);
+    }
+
+    void Change(COLORREF colFg, COLORREF colBg)
+    {
+        if ( colFg != CLR_INVALID )
+        {
+            m_oldColFg = ::SetTextColor(m_hdc, colFg);
+            if ( m_oldColFg == CLR_INVALID )
+            {
+                wxLogLastError(_T("SetTextColor"));
+            }
+        }
+        else
+        {
+            m_oldColFg = CLR_INVALID;
+        }
+
+        if ( colBg != CLR_INVALID )
+        {
+            m_oldColBg = ::SetBkColor(m_hdc, colBg);
+            if ( m_oldColBg == CLR_INVALID )
+            {
+                wxLogLastError(_T("SetBkColor"));
+            }
+        }
+        else
+        {
+            m_oldColBg = CLR_INVALID;
+        }
+    }
+
+private:
+    const HDC m_hdc;
+    COLORREF m_oldColFg,
+             m_oldColBg;
+
+    wxDECLARE_NO_COPY_CLASS(wxTextColoursChanger);
+};
+
+// background mode
+class wxBkModeChanger
+{
+public:
+    // set background mode to opaque if mode != wxBRUSHSTYLE_TRANSPARENT
+    wxBkModeChanger(HDC hdc, int mode)
+        : m_hdc(hdc)
+    {
+        Change(mode);
+    }
+
+    ~wxBkModeChanger()
+    {
+        if ( m_oldMode )
+            ::SetBkMode(m_hdc, m_oldMode);
+    }
+
+protected:
+    // this ctor doesn't change mode immediately, call Change() later to do it
+    // only if needed
+    wxBkModeChanger(HDC hdc) : m_hdc(hdc) { m_oldMode = 0; }
+
+    void Change(int mode)
+    {
+        m_oldMode = ::SetBkMode(m_hdc, mode == wxBRUSHSTYLE_TRANSPARENT
+                                        ? TRANSPARENT
+                                        : OPAQUE);
+        if ( !m_oldMode )
+        {
+            wxLogLastError(_T("SetBkMode"));
+        }
+    }
+
+private:
+    const HDC m_hdc;
+    int m_oldMode;
+
+    wxDECLARE_NO_COPY_CLASS(wxBkModeChanger);
+};
+
+} // namespace wxMSWImpl
+
+#endif // _MSW_PRIVATE_DC_H_
+