docs/latex/wx/renderer.tex

   1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2 %% Name:        renderer.tex
   3 %% Purpose:     wxRenderer and wxRendererNative documentation
   4 %% Author:      Vadim Zeitlin
   5 %% Modified by:
   6 %% Created:     06.08.03
   7 %% RCS-ID:      $Id$
   8 %% Copyright:   (c) 2003 Vadim Zeitlin <vadim@wxwindows.org>
   9 %% License:     wxWindows license
  10 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  11
  12 \section{\class{wxRendererNative}}\label{wxrenderernative}
  13
  14 First, a brief introduction into what is wxRenderer and why is it needed.
  15
  16 Usually wxWindows uses the underlying low level GUI system to draw all the
  17 controls -- this is what we mean when we say that it is a ``native'' framework.
  18 However not all controls exist under all (or even any) platforms and in this
  19 case wxWindows provides a default, generic, implementation of them written in
  20 wxWindows itself.
  21
  22 These controls however don't have the native appearance if only the standard
  23 line drawing and other graphics primitives are used if only because the native
  24 appearance is different under different platforms while the lines are always
  25 drawn in the same way.
  26
  27 This is why we have renderers: wxRenderer is a class which virtualizes the
  28 drawing, i.e. it abstracts the drawing operations and allows you to draw a,
  29 say, button, without caring about how exactly this is done. Of course, as we
  30 can draw the button differently in different renderers, this also allows us to
  31 emulate the native look and feel.
  32
  33
  34 So the renderers work by exposing a big set of high-level drawing functions
  35 which are used by the generic controls. There is always a default global
  36 renderer but it may be changed or extended by the user, see
  37 \helpref{Render sample}{samplerender}.
  38
  39 All drawing functions take some standard parameters:
  40 \begin{itemize}
  41     \item \arg{win} is the window being drawn. it is normally not used and when
  42           it is it should only be used as a generic \helpref{wxWindow}{wxwindow}
  43           (in order to get its low level handle, for example), but you should
  44           \emph{not} assume that it is of some given type as the same renderer
  45           function may be reused for drawing different kinds of control.
  46     \item \arg{dc} is the \helpref{wxDC}{wxdc} to draw on, only this device
  47           context should be used for drawing. It is not necessary to restore
  48           pens and brushes for it on function exit but, on the other hand, you
  49           shouldn't assume that it is in any specific state on function entry
  50           neither: the rendering functions should always prepare it.
  51     \item \arg{rect} the bounding rectangle for the element to be drawn
  52     \item \arg{flags} the optional flags (none by default) which can be a
  53           combination of the \texttt{wxCONTROL\_XXX} constants below
  54 \end{itemize}
  55
  56 \wxheading{Constants}
  57
  58 The following rendering flags are defined:
  59 \begin{verbatim}
  60 enum
  61 {
  62     wxCONTROL_DISABLED   = 0x00000001,  // control is disabled
  63     wxCONTROL_FOCUSED    = 0x00000002,  // currently has keyboard focus
  64     wxCONTROL_PRESSED    = 0x00000004,  // (button) is pressed
  65     wxCONTROL_ISDEFAULT  = 0x00000008,  // only applies to the buttons
  66     wxCONTROL_ISSUBMENU  = wxCONTROL_ISDEFAULT, // only for menu items
  67     wxCONTROL_EXPANDED   = wxCONTROL_ISDEFAULT, // only for the tree items
  68     wxCONTROL_CURRENT    = 0x00000010,  // mouse is currently over the control
  69     wxCONTROL_SELECTED   = 0x00000020,  // selected item in e.g. listbox
  70     wxCONTROL_CHECKED    = 0x00000040,  // (check/radio button) is checked
  71     wxCONTROL_CHECKABLE  = 0x00000080   // (menu) item can be checked
  72 };
  73 \end{verbatim}
  74
  75
  76 \wxheading{Derived from}
  77
  78 No base class
  79
  80 \wxheading{Include files}
  81
  82 <wx/renderer.h>
  83
  84
  85 \latexignore{\rtfignore{\wxheading{Members}}}
  86
  87
  88 \membersection{wxRendererNative::\destruct{wxRendererNative}}\label{wxrenderernativedtor}
  89
  90 \func{}{\destruct{wxRendererNative}}{\void}
  91
  92 Virtual destructor as for any base class.
  93
  94
  95 \membersection{wxRendererNative::DrawHeaderButton}\label{wxrenderernativedrawheaderbutton}
  96
  97 \func{void}{DrawHeaderButton}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags = 0}}
  98
  99 Draw the header control button (used by \helpref{wxListCtrl}{wxlistctrl}).
 100
 101
 102 \membersection{wxRendererNative::DrawSplitterBorder}\label{wxrenderernativedrawsplitterborder}
 103
 104 \func{void}{DrawSplitterBorder}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags = 0}}
 105
 106 Draw the border for sash window: this border must be such that the sash
 107 drawn by \helpref{DrawSash}{wxrenderernativedrawsplittersash} blends into it
 108 well.
 109
 110
 111 \membersection{wxRendererNative::DrawSplitterSash}\label{wxrenderernativedrawsplittersash}
 112
 113 \func{void}{DrawSplitterSash}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxSize\& }{size}, \param{wxCoord }{position}, \param{wxOrientation }{orient}, \param{int }{flags = 0}}
 114
 115 Draw a sash. The \arg{orient} parameter defines whether the sash should be
 116 vertical or horizontal and how should the \arg{position} be interpreted.
 117
 118
 119 \membersection{wxRendererNative::DrawTreeItemButton}\label{wxrenderernativedrawtreeitembutton}
 120
 121 \func{void}{DrawTreeItemButton}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags = 0}}
 122
 123 Draw the expanded/collapsed icon for a tree control item. To draw an expanded
 124 button the \arg{flags} parameter must contain {\tt wxCONTROL\_EXPANDED} bit.
 125
 126
 127 \membersection{wxRendererNative::Get}\label{wxrenderernativeget}
 128
 129 \func{wxRendererNative\&}{Get}{\void}
 130
 131 Return the currently used renderer.
 132
 133
 134 \membersection{wxRendererNative::GetDefault}\label{wxrenderernativegetdefault}
 135
 136 \func{wxRendererNative\&}{GetDefault}{\void}
 137
 138 Return the default (native) implementation for this platform -- this is also
 139 the one used by default but this may be changed by calling
 140 \helpref{Set}{wxrenderernativeset} in which case the return value of this
 141 method may be different from the return value of \helpref{Get}{wxrenderernativeget}.
 142
 143
 144 \membersection{wxRendererNative::GetGeneric}\label{wxrenderernativegetgeneric}
 145
 146 \func{wxRendererNative\&}{GetGeneric}{\void}
 147
 148 Return the generic implementation of the renderer. Under some platforms, this
 149 is the default renderer implementation, others have platform-specific default
 150 renderer which can be retrieved by calling \helpref{GetDefault}{wxrenderernativegetdefault}.
 151
 152
 153 \membersection{wxRendererNative::GetSplitterParams}\label{wxrenderernativegetsplitterparams}
 154
 155 \func{wxSplitterRenderParams}{GetSplitterParams}{\param{const wxWindow* }{win}}
 156
 157 Get the splitter parameters, see
 158 \helpref{wxSplitterRenderParams}{wxsplitterrenderparams}.
 159
 160
 161 \membersection{wxRendererNative::GetVersion}\label{wxrenderernativegetversion}
 162
 163 \constfunc{wxRendererVersion}{GetVersion}{\void}
 164
 165 This function is used for version checking: \helpref{Load}{wxrenderernativeload}
 166 refuses to load any shared libraries implementing an older or incompatible
 167 version.
 168
 169 The implementation of this method is always the same in all renderers (simply
 170 construct \helpref{wxRendererVersion}{wxrendererversion} using the
 171 {\tt wxRendererVersion::Current\_XXX} values), but it has to be in the derived,
 172 not base, class, to detect mismatches between the renderers versions and so you
 173 have to implement it anew in all renderers.
 174
 175
 176 \membersection{wxRendererNative::Load}\label{wxrenderernativeload}
 177
 178 \func{wxRendererNative*}{Load}{\param{const wxString\& }{name}}
 179
 180 Load the renderer from the specified DLL, the returned pointer must be
 181 deleted by caller if not {\tt NULL} when it is not used any more.
 182
 183 The \arg{name} should be just the base name of the renderer and not the full
 184 name of the DLL file which is constructed differently (using
 185 \helpref{wxDynamicLibrary::CanonicalizePluginName}{wxdynamiclibrarycanonicalizepluginname})
 186 on different systems.
 187
 188
 189 \membersection{wxRendererNative::Set}\label{wxrenderernativeset}
 190
 191 \func{wxRendererNative*}{Set}{\param{wxRendererNative* }{renderer}}
 192
 193 Set the renderer to use, passing {\tt NULL} reverts to using the default
 194 renderer (the global renderer must always exist).
 195
 196 Return the previous renderer used with Set() or {\tt NULL} if none.
 197