include/wx/private/markupparserattr.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/private/markupparserattr.h
   3 // Purpose:     Classes mapping markup attributes to wxFont/wxColour.
   4 // Author:      Vadim Zeitlin
   5 // Created:     2011-02-18
   6 // RCS-ID:      $Id: wxhead.h,v 1.12 2010-04-22 12:44:51 zeitlin Exp $
   7 // Copyright:   (c) 2011 Vadim Zeitlin <vadim@wxwidgets.org>
   8 // Licence:     wxWindows licence
   9 ///////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef _WX_PRIVATE_MARKUPPARSERATTR_H_
  12 #define _WX_PRIVATE_MARKUPPARSERATTR_H_
  13
  14 #include "wx/private/markupparser.h"
  15
  16 #include "wx/stack.h"
  17
  18 #include "wx/colour.h"
  19 #include "wx/font.h"
  20
  21 // ----------------------------------------------------------------------------
  22 // wxMarkupParserAttrOutput: simplified wxFont-using version of the above.
  23 // ----------------------------------------------------------------------------
  24
  25 // This class assumes that wxFont and wxColour are used to perform all the
  26 // markup tags and implements the base class virtual functions in terms of
  27 // OnAttr{Start,End}() only.
  28 //
  29 // Notice that you still must implement OnText() inherited from the base class
  30 // when deriving from this one.
  31 class wxMarkupParserAttrOutput : public wxMarkupParserOutput
  32 {
  33 public:
  34     // A simple container of font and colours.
  35     struct Attr
  36     {
  37         Attr(const wxFont& font_,
  38              const wxColour& foreground_ = wxColour(),
  39              const wxColour& background_ = wxColour())
  40             : font(font_), foreground(foreground_), background(background_)
  41         {
  42         }
  43
  44         wxFont font;
  45         wxColour foreground,
  46                  background;
  47     };
  48
  49
  50     // This object must be initialized with the font and colours to use
  51     // initially, i.e. the ones used before any tags in the string.
  52     wxMarkupParserAttrOutput(const wxFont& font,
  53                              const wxColour& foreground,
  54                              const wxColour& background)
  55     {
  56         m_attrs.push(Attr(font, foreground, background));
  57     }
  58
  59     // Indicates the change of the font and/or colours used. Any of the
  60     // fields of the argument may be invalid indicating that the corresponding
  61     // attribute didn't actually change.
  62     virtual void OnAttrStart(const Attr& attr) = 0;
  63
  64     // Indicates the end of the region affected by the given attributes
  65     // (the same ones that were passed to the matching OnAttrStart(), use
  66     // GetAttr() to get the ones that will be used from now on).
  67     virtual void OnAttrEnd(const Attr& attr) = 0;
  68
  69
  70     // Implement all pure virtual methods inherited from the base class in
  71     // terms of our own ones.
  72     virtual void OnBoldStart() { DoChangeFont(&wxFont::Bold); }
  73     virtual void OnBoldEnd() { DoEndAttr(); }
  74
  75     virtual void OnItalicStart() { DoChangeFont(&wxFont::Italic); }
  76     virtual void OnItalicEnd() { DoEndAttr(); }
  77
  78     virtual void OnUnderlinedStart() { DoChangeFont(&wxFont::Underlined); }
  79     virtual void OnUnderlinedEnd() { DoEndAttr(); }
  80
  81     virtual void OnStrikethroughStart() { } // TODO: No support in wxFont yet.
  82     virtual void OnStrikethroughEnd() { }
  83
  84     virtual void OnBigStart() { DoChangeFont(&wxFont::Larger); }
  85     virtual void OnBigEnd() { DoEndAttr(); }
  86
  87     virtual void OnSmallStart() { DoChangeFont(&wxFont::Smaller); }
  88     virtual void OnSmallEnd() { DoEndAttr(); }
  89
  90     virtual void OnTeletypeStart()
  91     {
  92         wxFont font(GetFont());
  93         font.SetFamily(wxFONTFAMILY_TELETYPE);
  94         DoSetFont(font);
  95     }
  96     virtual void OnTeletypeEnd() { DoEndAttr(); }
  97
  98     virtual void OnSpanStart(const wxMarkupSpanAttributes& spanAttr)
  99     {
 100         wxFont font(GetFont());
 101         if ( !spanAttr.m_fontFace.empty() )
 102             font.SetFaceName(spanAttr.m_fontFace);
 103
 104         FontModifier<wxFontWeight>()(spanAttr.m_isBold,
 105                                      font, &wxFont::SetWeight,
 106                                      wxFONTWEIGHT_NORMAL, wxFONTWEIGHT_BOLD);
 107
 108         FontModifier<wxFontStyle>()(spanAttr.m_isItalic,
 109                                     font, &wxFont::SetStyle,
 110                                     wxFONTSTYLE_NORMAL, wxFONTSTYLE_ITALIC);
 111
 112         FontModifier<bool>()(spanAttr.m_isUnderlined,
 113                              font, &wxFont::SetUnderlined,
 114                              false, true);
 115
 116         // TODO: No support for strike-through yet.
 117
 118         switch ( spanAttr.m_sizeKind )
 119         {
 120             case wxMarkupSpanAttributes::Size_Unspecified:
 121                 break;
 122
 123             case wxMarkupSpanAttributes::Size_Relative:
 124                 if ( spanAttr.m_fontSize > 0 )
 125                     font.MakeLarger();
 126                 else
 127                     font.MakeSmaller();
 128                 break;
 129
 130             case wxMarkupSpanAttributes::Size_Symbolic:
 131                 // The values of font size intentionally coincide with the
 132                 // values of wxFontSymbolicSize enum elements so simply cast
 133                 // one to the other.
 134                 font.SetSymbolicSize(
 135                     static_cast<wxFontSymbolicSize>(spanAttr.m_fontSize)
 136                 );
 137                 break;
 138
 139             case wxMarkupSpanAttributes::Size_PointParts:
 140                 font.SetPointSize((spanAttr.m_fontSize + 1023)/1024);
 141                 break;
 142         }
 143
 144
 145         const Attr attr(font, spanAttr.m_fgCol, spanAttr.m_bgCol);
 146         OnAttrStart(attr);
 147
 148         m_attrs.push(attr);
 149     }
 150
 151     virtual void OnSpanEnd(const wxMarkupSpanAttributes& WXUNUSED(spanAttr))
 152     {
 153         DoEndAttr();
 154     }
 155
 156 protected:
 157     // Get the current attributes, i.e. the ones that should be used for
 158     // rendering (or measuring or whatever) the text at the current position in
 159     // the string.
 160     //
 161     // It may be called from OnAttrStart() to get the old attributes used
 162     // before and from OnAttrEnd() to get the new attributes that will be used
 163     // from now on but is mostly meant to be used from overridden OnText()
 164     // implementations.
 165     const Attr& GetAttr() const { return m_attrs.top(); }
 166
 167     // A shortcut for accessing the font of the current attribute.
 168     const wxFont& GetFont() const { return GetAttr().font; }
 169
 170 private:
 171     // Change only the font to the given one. Call OnAttrStart() to notify
 172     // about the change and update the attributes stack.
 173     void DoSetFont(const wxFont& font)
 174     {
 175         const Attr attr(font);
 176
 177         OnAttrStart(attr);
 178
 179         m_attrs.push(attr);
 180     }
 181
 182     // Apply the given function to the font currently on top of the font stack,
 183     // push the new font on the stack and call OnAttrStart() with it.
 184     void DoChangeFont(wxFont (wxFont::*func)() const)
 185     {
 186         DoSetFont((GetFont().*func)());
 187     }
 188
 189     void DoEndAttr()
 190     {
 191         const Attr attr(m_attrs.top());
 192         m_attrs.pop();
 193
 194         OnAttrEnd(attr);
 195     }
 196
 197     // A helper class used to apply the given function to a wxFont object
 198     // depending on the value of an OptionalBool.
 199     template <typename T>
 200     struct FontModifier
 201     {
 202         FontModifier() { }
 203
 204         void operator()(wxMarkupSpanAttributes::OptionalBool isIt,
 205                         wxFont& font,
 206                         void (wxFont::*func)(T),
 207                         T noValue,
 208                         T yesValue)
 209         {
 210             switch ( isIt )
 211             {
 212                 case wxMarkupSpanAttributes::Unspecified:
 213                     break;
 214
 215                 case wxMarkupSpanAttributes::No:
 216                     (font.*func)(noValue);
 217                     break;
 218
 219                 case wxMarkupSpanAttributes::Yes:
 220                     (font.*func)(yesValue);
 221                     break;
 222             }
 223         }
 224     };
 225
 226
 227     wxStack<Attr> m_attrs;
 228
 229     wxDECLARE_NO_COPY_CLASS(wxMarkupParserAttrOutput);
 230 };
 231
 232 #endif // _WX_PRIVATE_MARKUPPARSERATTR_H_