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:     wxWidgets license
  10 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  11
  12 \section{\class{wxRendererNative}}\label{wxrenderernative}
  13
  14 First, a brief introduction to wxRenderer and why it is needed.
  15
  16 Usually wxWidgets 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 wxWidgets provides a default, generic, implementation of them written in
  20 wxWidgets itself.
  21
  22 These controls don't have the native appearance if only the standard
  23 line drawing and other graphics primitives are used, 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 say, a
  29 button, without caring about exactly how 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 So the renderers work by exposing a large set of high-level drawing functions
  34 which are used by the generic controls. There is always a default global
  35 renderer but it may be changed or extended by the user, see
  36 \helpref{Render sample}{samplerender}.
  37
  38 All drawing functions take some standard parameters:
  39 \begin{itemize}
  40 \item \arg{win} is the window being drawn. It is normally not used and when
  41 it is it should only be used as a generic \helpref{wxWindow}{wxwindow}
  42 (in order to get its low level handle, for example), but you should
  43 \emph{not} assume that it is of some given type as the same renderer
  44 function may be reused for drawing different kinds of control.
  45 \item \arg{dc} is the \helpref{wxDC}{wxdc} to draw on. Only this device
  46 context should be used for drawing. It is not necessary to restore
  47 pens and brushes for it on function exit but, on the other hand, you
  48 shouldn't assume that it is in any specific state on function entry:
  49 the rendering functions should always prepare it.
  50 \item \arg{rect} the bounding rectangle for the element to be drawn.
  51 \item \arg{flags} the optional flags (none by default) which can be a
  52 combination of the \texttt{wxCONTROL\_XXX} constants below.
  53 \end{itemize}
  54
  55 \wxheading{Constants}
  56
  57 The following rendering flags are defined:
  58
  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 \wxheading{Derived from}
  76
  77 No base class
  78
  79 \wxheading{Include files}
  80
  81 <wx/renderer.h>
  82
  83
  84 \latexignore{\rtfignore{\wxheading{Members}}}
  85
  86
  87 \membersection{wxRendererNative::\destruct{wxRendererNative}}\label{wxrenderernativedtor}
  88
  89 \func{}{\destruct{wxRendererNative}}{\void}
  90
  91 Virtual destructor as for any base class.
  92
  93
  94 \membersection{wxRendererNative::DrawHeaderButton}\label{wxrenderernativedrawheaderbutton}
  95
  96 \func{void}{DrawHeaderButton}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags = 0}}
  97
  98 Draw the header control button (used by \helpref{wxListCtrl}{wxlistctrl}).
  99
 100
 101 \membersection{wxRendererNative::DrawSplitterBorder}\label{wxrenderernativedrawsplitterborder}
 102
 103 \func{void}{DrawSplitterBorder}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags = 0}}
 104
 105 Draw the border for sash window: this border must be such that the sash
 106 drawn by \helpref{DrawSash}{wxrenderernativedrawsplittersash} blends into it
 107 well.
 108
 109
 110 \membersection{wxRendererNative::DrawSplitterSash}\label{wxrenderernativedrawsplittersash}
 111
 112 \func{void}{DrawSplitterSash}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxSize\& }{size}, \param{wxCoord }{position}, \param{wxOrientation }{orient}, \param{int }{flags = 0}}
 113
 114 Draw a sash. The \arg{orient} parameter defines whether the sash should be
 115 vertical or horizontal and how should the \arg{position} be interpreted.
 116
 117
 118 \membersection{wxRendererNative::DrawTreeItemButton}\label{wxrenderernativedrawtreeitembutton}
 119
 120 \func{void}{DrawTreeItemButton}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags = 0}}
 121
 122 Draw the expanded/collapsed icon for a tree control item. To draw an expanded
 123 button the \arg{flags} parameter must contain {\tt wxCONTROL\_EXPANDED} bit.
 124
 125
 126 \membersection{wxRendererNative::Get}\label{wxrenderernativeget}
 127
 128 \func{wxRendererNative\&}{Get}{\void}
 129
 130 Return the currently used renderer.
 131
 132
 133 \membersection{wxRendererNative::GetDefault}\label{wxrenderernativegetdefault}
 134
 135 \func{wxRendererNative\&}{GetDefault}{\void}
 136
 137 Return the default (native) implementation for this platform -- this is also
 138 the one used by default but this may be changed by calling
 139 \helpref{Set}{wxrenderernativeset} in which case the return value of this
 140 method may be different from the return value of \helpref{Get}{wxrenderernativeget}.
 141
 142
 143 \membersection{wxRendererNative::GetGeneric}\label{wxrenderernativegetgeneric}
 144
 145 \func{wxRendererNative\&}{GetGeneric}{\void}
 146
 147 Return the generic implementation of the renderer. Under some platforms, this
 148 is the default renderer implementation, others have platform-specific default
 149 renderer which can be retrieved by calling \helpref{GetDefault}{wxrenderernativegetdefault}.
 150
 151
 152 \membersection{wxRendererNative::GetSplitterParams}\label{wxrenderernativegetsplitterparams}
 153
 154 \func{wxSplitterRenderParams}{GetSplitterParams}{\param{const wxWindow* }{win}}
 155
 156 Get the splitter parameters, see
 157 \helpref{wxSplitterRenderParams}{wxsplitterrenderparams}.
 158
 159
 160 \membersection{wxRendererNative::GetVersion}\label{wxrenderernativegetversion}
 161
 162 \constfunc{wxRendererVersion}{GetVersion}{\void}
 163
 164 This function is used for version checking: \helpref{Load}{wxrenderernativeload}
 165 refuses to load any shared libraries implementing an older or incompatible
 166 version.
 167
 168 The implementation of this method is always the same in all renderers (simply
 169 construct \helpref{wxRendererVersion}{wxrendererversion} using the
 170 {\tt wxRendererVersion::Current\_XXX} values), but it has to be in the derived,
 171 not base, class, to detect mismatches between the renderers versions and so you
 172 have to implement it anew in all renderers.
 173
 174
 175 \membersection{wxRendererNative::Load}\label{wxrenderernativeload}
 176
 177 \func{wxRendererNative*}{Load}{\param{const wxString\& }{name}}
 178
 179 Load the renderer from the specified DLL, the returned pointer must be
 180 deleted by caller if not {\tt NULL} when it is not used any more.
 181
 182 The \arg{name} should be just the base name of the renderer and not the full
 183 name of the DLL file which is constructed differently (using
 184 \helpref{wxDynamicLibrary::CanonicalizePluginName}{wxdynamiclibrarycanonicalizepluginname})
 185 on different systems.
 186
 187
 188 \membersection{wxRendererNative::Set}\label{wxrenderernativeset}
 189
 190 \func{wxRendererNative*}{Set}{\param{wxRendererNative* }{renderer}}
 191
 192 Set the renderer to use, passing {\tt NULL} reverts to using the default
 193 renderer (the global renderer must always exist).
 194
 195 Return the previous renderer used with Set() or {\tt NULL} if none.
 196