src/common/rendcmn.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        common/rendcmn.cpp
   3 // Purpose:     wxRendererNative common functions
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     28.07.03
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2003 Vadim Zeitlin <vadim@wxwindows.org>
   9 // License:     wxWindows license
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #include "wx/wxprec.h"
  21
  22 #ifdef __BORLANDC__
  23     #pragma hdrstop
  24 #endif
  25
  26 #ifndef WX_PRECOMP
  27 #endif //WX_PRECOMP
  28
  29 #include "wx/apptrait.h"
  30 #include "wx/renderer.h"
  31
  32 #include "wx/ptr_scpd.h"
  33
  34 // ----------------------------------------------------------------------------
  35 // wxRendererPtr: auto pointer holding the global renderer
  36 // ----------------------------------------------------------------------------
  37
  38 wxDECLARE_SCOPED_PTR(wxRendererNative, wxRendererPtrBase);
  39 wxDEFINE_SCOPED_PTR(wxRendererNative, wxRendererPtrBase);
  40
  41 class wxRendererPtr : public wxRendererPtrBase
  42 {
  43 public:
  44     wxRendererPtr() : wxRendererPtrBase(NULL) { m_initialized = false; }
  45
  46     // return true if we have a renderer, false otherwise
  47     bool IsOk()
  48     {
  49         if ( !m_initialized )
  50         {
  51             // only try to create the renderer once
  52             m_initialized = true;
  53
  54             DoInit();
  55         }
  56
  57         return get() != NULL;
  58     }
  59
  60 private:
  61     void DoInit()
  62     {
  63         wxAppTraits *traits = wxTheApp ? wxTheApp->GetTraits() : NULL;
  64         if ( traits )
  65         {
  66             // ask the traits object to create a renderer for us
  67             reset(traits->CreateRenderer());
  68         }
  69     }
  70
  71     bool m_initialized;
  72
  73     DECLARE_NO_COPY_CLASS(wxRendererPtr)
  74 };
  75
  76 // ============================================================================
  77 // wxRendererNative implementation
  78 // ============================================================================
  79
  80 /* static */
  81 wxRendererNative& wxRendererNative::Get()
  82 {
  83     static wxRendererPtr s_renderer;
  84
  85     return s_renderer.IsOk() ? *s_renderer.get() : GetDefault();
  86 }
  87