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 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     wxCONTROL_UNDETERMINED = wxCONTROL_CHECKABLE  // (check) undetermined state
  73 };
  74 \end{verbatim}
  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::DrawCheckBox}\label{wxrenderernativedrawcheckbox}
  96
  97 \func{void}{DrawCheckBox}{\param{wxWindow *}{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags}}
  98
  99 Draw a check box (used by wxDataViewCtrl).
 100
 101 \arg{flags} may have the \texttt{wxCONTROL\_CHECKED}, \texttt{wxCONTROL\_CURRENT} or
 102 \texttt{wxCONTROL\_UNDETERMINED} bit set.
 103
 104
 105 \membersection{wxRendererNative::DrawComboBoxDropButton}\label{wxrenderernativedrawcomboboxdropbutton}
 106
 107 \func{void}{DrawComboBoxDropButton}{\param{wxWindow *}{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags}}
 108
 109 Draw a button like the one used by \helpref{wxComboBox}{wxcombobox} to show a
 110 drop down window. The usual appearance is a downwards pointing arrow.
 111
 112 \arg{flags} may have the \texttt{wxCONTROL\_PRESSED} or \texttt{wxCONTROL\_CURRENT} bit set.
 113
 114
 115 \membersection{wxRendererNative::DrawDropArrow}\label{wxrenderernativedrawdroparrow}
 116
 117 \func{void}{DrawDropArrow}{\param{wxWindow *}{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags}}
 118
 119 Draw a drop down arrow that is suitable for use outside a combo box. Arrow will have
 120 transparent background.
 121
 122 \arg{rect} is not entirely filled by the arrow. Instead, you should use bounding
 123 rectangle of a drop down button which arrow matches the size you need.
 124 \arg{flags} may have the \texttt{wxCONTROL\_PRESSED} or \texttt{wxCONTROL\_CURRENT} bit set.
 125
 126
 127 \membersection{wxRendererNative::DrawHeaderButton}\label{wxrenderernativedrawheaderbutton}
 128
 129 \func{void}{DrawHeaderButton}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags = 0}}
 130
 131 Draw the header control button (used by \helpref{wxListCtrl}{wxlistctrl}).
 132
 133
 134 \membersection{wxRendererNative::DrawPushButton}\label{wxrenderernativedrawpushbutton}
 135
 136 \func{void}{DrawPushButton}{\param{wxWindow *}{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags}}
 137
 138 Draw a blank push button that looks very similar to \helpref{wxButton}{wxbutton}.
 139
 140 \arg{flags} may have the \texttt{wxCONTROL\_PRESSED}, \texttt{wxCONTROL\_CURRENT} or
 141 \texttt{wxCONTROL\_ISDEFAULT} bit set.
 142
 143
 144 \membersection{wxRendererNative::DrawSplitterBorder}\label{wxrenderernativedrawsplitterborder}
 145
 146 \func{void}{DrawSplitterBorder}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags = 0}}
 147
 148 Draw the border for sash window: this border must be such that the sash
 149 drawn by \helpref{DrawSash}{wxrenderernativedrawsplittersash} blends into it
 150 well.
 151
 152
 153 \membersection{wxRendererNative::DrawSplitterSash}\label{wxrenderernativedrawsplittersash}
 154
 155 \func{void}{DrawSplitterSash}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxSize\& }{size}, \param{wxCoord }{position}, \param{wxOrientation }{orient}, \param{int }{flags = 0}}
 156
 157 Draw a sash. The \arg{orient} parameter defines whether the sash should be
 158 vertical or horizontal and how the \arg{position} should be interpreted.
 159
 160
 161 \membersection{wxRendererNative::DrawTreeItemButton}\label{wxrenderernativedrawtreeitembutton}
 162
 163 \func{void}{DrawTreeItemButton}{\param{wxWindow* }{win}, \param{wxDC\& }{dc}, \param{const wxRect\& }{rect}, \param{int }{flags = 0}}
 164
 165 Draw the expanded/collapsed icon for a tree control item. To draw an expanded
 166 button the \arg{flags} parameter must contain {\tt wxCONTROL\_EXPANDED} bit.
 167
 168
 169 \membersection{wxRendererNative::Get}\label{wxrenderernativeget}
 170
 171 \func{wxRendererNative\&}{Get}{\void}
 172
 173 Return the currently used renderer.
 174
 175
 176 \membersection{wxRendererNative::GetDefault}\label{wxrenderernativegetdefault}
 177
 178 \func{wxRendererNative\&}{GetDefault}{\void}
 179
 180 Return the default (native) implementation for this platform -- this is also
 181 the one used by default but this may be changed by calling
 182 \helpref{Set}{wxrenderernativeset} in which case the return value of this
 183 method may be different from the return value of \helpref{Get}{wxrenderernativeget}.
 184
 185
 186 \membersection{wxRendererNative::GetGeneric}\label{wxrenderernativegetgeneric}
 187
 188 \func{wxRendererNative\&}{GetGeneric}{\void}
 189
 190 Return the generic implementation of the renderer. Under some platforms, this
 191 is the default renderer implementation, others have platform-specific default
 192 renderer which can be retrieved by calling \helpref{GetDefault}{wxrenderernativegetdefault}.
 193
 194
 195 \membersection{wxRendererNative::GetSplitterParams}\label{wxrenderernativegetsplitterparams}
 196
 197 \func{wxSplitterRenderParams}{GetSplitterParams}{\param{const wxWindow* }{win}}
 198
 199 Get the splitter parameters, see
 200 \helpref{wxSplitterRenderParams}{wxsplitterrenderparams}.
 201
 202
 203 \membersection{wxRendererNative::GetVersion}\label{wxrenderernativegetversion}
 204
 205 \constfunc{wxRendererVersion}{GetVersion}{\void}
 206
 207 This function is used for version checking: \helpref{Load}{wxrenderernativeload}
 208 refuses to load any shared libraries implementing an older or incompatible
 209 version.
 210
 211 The implementation of this method is always the same in all renderers (simply
 212 construct \helpref{wxRendererVersion}{wxrendererversion} using the
 213 {\tt wxRendererVersion::Current\_XXX} values), but it has to be in the derived,
 214 not base, class, to detect mismatches between the renderers versions and so you
 215 have to implement it anew in all renderers.
 216
 217
 218 \membersection{wxRendererNative::Load}\label{wxrenderernativeload}
 219
 220 \func{wxRendererNative*}{Load}{\param{const wxString\& }{name}}
 221
 222 Load the renderer from the specified DLL, the returned pointer must be
 223 deleted by caller if not {\tt NULL} when it is not used any more.
 224
 225 The \arg{name} should be just the base name of the renderer and not the full
 226 name of the DLL file which is constructed differently (using
 227 \helpref{wxDynamicLibrary::CanonicalizePluginName}{wxdynamiclibrarycanonicalizepluginname})
 228 on different systems.
 229
 230
 231 \membersection{wxRendererNative::Set}\label{wxrenderernativeset}
 232
 233 \func{wxRendererNative*}{Set}{\param{wxRendererNative* }{renderer}}
 234
 235 Set the renderer to use, passing {\tt NULL} reverts to using the default
 236 renderer (the global renderer must always exist).
 237
 238 Return the previous renderer used with Set() or {\tt NULL} if none.