include/wx/generic/custombgwin.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/generic/custombgwin.h
   3 // Purpose:     Generic implementation of wxCustomBackgroundWindow.
   4 // Author:      Vadim Zeitlin
   5 // Created:     2011-10-10
   6 // Copyright:   (c) 2011 Vadim Zeitlin <vadim@wxwidgets.org>
   7 // Licence:     wxWindows licence
   8 ///////////////////////////////////////////////////////////////////////////////
   9
  10 #ifndef _WX_GENERIC_CUSTOMBGWIN_H_
  11 #define _WX_GENERIC_CUSTOMBGWIN_H_
  12
  13 #include "wx/bitmap.h"
  14
  15 // A helper to avoid template bloat: this class contains all type-independent
  16 // code of wxCustomBackgroundWindow<> below.
  17 class wxCustomBackgroundWindowGenericBase : public wxCustomBackgroundWindowBase
  18 {
  19 public:
  20     wxCustomBackgroundWindowGenericBase() { }
  21
  22 protected:
  23     void DoEraseBackground(wxEraseEvent& event, wxWindow* win)
  24     {
  25         wxDC& dc = *event.GetDC();
  26
  27         const wxSize clientSize = win->GetClientSize();
  28         const wxSize bitmapSize = m_bitmapBg.GetSize();
  29
  30         for ( int x = 0; x < clientSize.x; x += bitmapSize.x )
  31         {
  32             for ( int y = 0; y < clientSize.y; y += bitmapSize.y )
  33             {
  34                 dc.DrawBitmap(m_bitmapBg, x, y);
  35             }
  36         }
  37     }
  38
  39
  40     // The bitmap used for painting the background if valid.
  41     wxBitmap m_bitmapBg;
  42
  43
  44     wxDECLARE_NO_COPY_CLASS(wxCustomBackgroundWindowGenericBase);
  45 };
  46
  47 // ----------------------------------------------------------------------------
  48 // wxCustomBackgroundWindow
  49 // ----------------------------------------------------------------------------
  50
  51 template <class W>
  52 class wxCustomBackgroundWindow : public W,
  53                                  public wxCustomBackgroundWindowGenericBase
  54 {
  55 public:
  56     typedef W BaseWindowClass;
  57
  58     wxCustomBackgroundWindow() { }
  59
  60 protected:
  61     virtual void DoSetBackgroundBitmap(const wxBitmap& bmp)
  62     {
  63         m_bitmapBg = bmp;
  64
  65         if ( m_bitmapBg.IsOk() )
  66         {
  67             BaseWindowClass::Connect
  68             (
  69                 wxEVT_ERASE_BACKGROUND,
  70                 wxEraseEventHandler(wxCustomBackgroundWindow::OnEraseBackground)
  71             );
  72         }
  73         else
  74         {
  75             BaseWindowClass::Disconnect
  76             (
  77                 wxEVT_ERASE_BACKGROUND,
  78                 wxEraseEventHandler(wxCustomBackgroundWindow::OnEraseBackground)
  79             );
  80         }
  81     }
  82
  83 private:
  84     // Event handler for erasing the background which is only used when we have
  85     // a valid background bitmap.
  86     void OnEraseBackground(wxEraseEvent& event)
  87     {
  88         DoEraseBackground(event, this);
  89     }
  90
  91
  92     wxDECLARE_NO_COPY_TEMPLATE_CLASS(wxCustomBackgroundWindow, W);
  93 };
  94
  95 #endif // _WX_GENERIC_CUSTOMBGWIN_H_