docs/latex/wx/helpinst.tex

   1 \section{\class{wxHelpController}}\label{wxhelpcontroller}
   2
   3 This is a family of classes by which
   4 applications may invoke a help viewer to provide on-line help.
   5
   6 A help controller allows an application to display help, at the contents
   7 or at a particular topic, and shut the help program down on termination.
   8 This avoids proliferation of many instances of the help viewer whenever the
   9 user requests a different topic via the application's menus or buttons.
  10
  11 Typically, an application will create a help controller instance
  12 when it starts, and immediately call {\bf Initialize}\rtfsp
  13 to associate a filename with it. The help viewer will only get run, however,
  14 just before the first call to display something.
  15
  16 Most help controller classes actually derive from wxHelpControllerBase and have
  17 names of the form wxXXXHelpController or wxHelpControllerXXX. An
  18 appropriate class is aliased to the name wxHelpController for each platform, as follows:
  19
  20 \begin{itemize}\itemsep=0pt
  21 \item On Windows, wxWinHelpController is used.
  22 \item On all other platforms, wxHtmlHelpController is used if wxHTML is
  23 compiled into wxWindows; otherwise wxExtHelpController is used (for invoking an external
  24 browser).
  25 \end{itemize}
  26
  27 The remaining help controller classes need to be named
  28 explicitly by an application that wishes to make use of them.
  29
  30 There are currently the following help controller classes defined:
  31
  32 \begin{itemize}\itemsep=0pt
  33 \item wxWinHelpController, for controlling Windows Help.
  34 \item wxCHMHelpController, for controlling MS HTML Help. To use this, you need to set wxUSE\_MS\_HTML\_HELP
  35 to 1 in setup.h and have htmlhelp.h header from Microsoft's HTML Help kit (you don't need
  36 VC++ specific htmlhelp.lib because wxWindows loads necessary DLL at runtime and so it
  37 works with all compilers).
  38 \item wxBestHelpController, for controlling MS HTML Help or, if Microsoft's runtime is
  39 not available, \helpref{wxHtmlHelpController}{wxhtmlhelpcontroller}. You need to provide
  40 {\bf both} CHM and HTB versions of the help file. For 32bit Windows only.
  41 \item wxExtHelpController, for controlling external browsers under Unix.
  42 The default browser is Netscape Navigator. The 'help' sample shows its use.
  43 \item \helpref{wxHtmlHelpController}{wxhtmlhelpcontroller}, a sophisticated help controller using \helpref{wxHTML}{wxhtml}, in
  44 a similar style to the Microsoft HTML Help viewer and using some of the same files.
  45 Although it has an API compatible with other help controllers, it has more advanced features, so it is
  46 recommended that you use the specific API for this class instead. Note that if you
  47 use .zip or .htb formats for your books, you
  48 must add this line to your application initialization: {\tt wxFileSystem::AddHandler(new wxZipFSHandler);}
  49 or nothing will be shown in your help window.
  50 \end{itemize}
  51
  52 \wxheading{Derived from}
  53
  54 wxHelpControllerBase\\
  55 \helpref{wxObject}{wxobject}
  56
  57 \wxheading{Include files}
  58
  59 <wx/help.h> (wxWindows chooses the appropriate help controller class)\\
  60 <wx/helpbase.h> (wxHelpControllerBase class)\\
  61 <wx/helpwin.h> (Windows Help controller)\\
  62 <wx/msw/helpchm.h> (MS HTML Help controller)\\
  63 <wx/generic/helpext.h> (external HTML browser controller)\\
  64 <wx/html/helpctrl.h> (wxHTML based help controller: wxHtmlHelpController)
  65
  66 \wxheading{See also}
  67
  68 \helpref{wxHtmlHelpController}{wxhtmlhelpcontroller}, \helpref{wxHTML}{wxhtml}
  69
  70 \latexignore{\rtfignore{\wxheading{Members}}}
  71
  72 \membersection{wxHelpController::wxHelpController}
  73
  74 \func{}{wxHelpController}{\void}
  75
  76 Constructs a help instance object, but does not invoke the help viewer.
  77
  78 \membersection{wxHelpController::\destruct{wxHelpController}}
  79
  80 \func{}{\destruct{wxHelpController}}{\void}
  81
  82 Destroys the help instance, closing down the viewer if it is running.
  83
  84 \membersection{wxHelpController::Initialize}\label{wxhelpcontrollerinitialize}
  85
  86 \func{virtual void}{Initialize}{\param{const wxString\& }{file}}
  87
  88 \func{virtual void}{Initialize}{\param{const wxString\& }{file}, \param{int}{ server}}
  89
  90 Initializes the help instance with a help filename, and optionally a server socket
  91 number if using wxHelp (now obsolete). Does not invoke the help viewer.
  92 This must be called directly after the help instance object is created and before
  93 any attempts to communicate with the viewer.
  94
  95 You may omit the file extension and a suitable one will be chosen. For
  96 wxHtmlHelpController, the extensions zip, htb and hhp will be appended while searching for
  97 a suitable file. For WinHelp, the hlp extension is appended.
  98
  99 \membersection{wxHelpController::DisplayBlock}\label{wxhelpcontrollerdisplayblock}
 100
 101 \func{virtual bool}{DisplayBlock}{\param{long}{ blockNo}}
 102
 103 If the help viewer is not running, runs it and displays the file at the given block number.
 104
 105 {\it WinHelp:} Refers to the context number.
 106
 107 {\it MS HTML Help:} Refers to the context number.
 108
 109 {\it External HTML help:} the same as for \helpref{wxHelpController::DisplaySection}{wxhelpcontrollerdisplaysection}.
 110
 111 {\it wxHtmlHelpController:} {\it sectionNo} is an identifier as specified in the {\tt .hhc} file. See \helpref{Help files format}{helpformat}.
 112
 113 This function is for backward compatibility only, and applications should use \helpref{wxHelpController}{wxhelpcontrollerdisplaysection} instead.
 114
 115 \membersection{wxHelpController::DisplayContents}\label{wxhelpcontrollerdisplaycontents}
 116
 117 \func{virtual bool}{DisplayContents}{\void}
 118
 119 If the help viewer is not running, runs it and displays the
 120 contents.
 121
 122 \membersection{wxHelpController::DisplayContextPopup}\label{wxhelpcontrollerdisplaycontextpopup}
 123
 124 \func{virtual bool}{DisplayContextPopup}{\param{int }{contextId}}
 125
 126 Displays the section as a popup window using a context id.
 127
 128 Returns false if unsuccessful or not implemented.
 129
 130 \membersection{wxHelpController::DisplaySection}\label{wxhelpcontrollerdisplaysection}
 131
 132 \func{virtual bool}{DisplaySection}{\param{const wxString\&}{ section}}
 133
 134 If the help viewer is not running, runs it and displays the given section.
 135
 136 The interpretation of {\it section} differs between help viewers. For most viewers,
 137 this call is equivalent to KeywordSearch. For MS HTML Help, wxHTML help and external HTML help,
 138 if {\it section} has a .htm
 139 or .html extension, that HTML file will be displayed; otherwise
 140 a keyword search is done.
 141
 142 \func{virtual bool}{DisplaySection}{\param{int}{ sectionNo}}
 143
 144 If the help viewer is not running, runs it and displays the given section.
 145
 146 {\it WinHelp, MS HTML Help} {\it sectionNo} is a context id.
 147
 148 {\it External HTML help:} wxExtHelpController implements {\it sectionNo} as an id in a map file, which is of the form:
 149
 150 \begin{verbatim}
 151 0  wx.html             ; Index
 152 1  wx34.html#classref  ; Class reference
 153 2  wx204.html          ; Function reference
 154 \end{verbatim}
 155
 156 {\it wxHtmlHelpController:} {\it sectionNo} is an identifier as specified in the {\tt .hhc} file. See \helpref{Help files format}{helpformat}.
 157
 158 See also the help sample for notes on how to specify section numbers for various help file formats.
 159
 160 \membersection{wxHelpController::DisplayTextPopup}\label{wxhelpcontrollerdisplaytextpopup}
 161
 162 \func{virtual bool}{DisplayTextPopup}{\param{const wxString\&}{ text}, \param{const wxPoint\& }{pos}}
 163
 164 Displays the text in a popup window, if possible.
 165
 166 Returns false if unsuccessful or not implemented.
 167
 168 \membersection{wxHelpController::GetFrameParameters}\label{wxhelpcontrollergetframeparameters}
 169
 170 \func{virtual wxFrame *}{GetFrameParameters}{\param{const wxSize * }{size = NULL}, \param{const wxPoint * }{pos = NULL},
 171  \param{bool *}{newFrameEachTime = NULL}}
 172
 173 wxHtmlHelpController returns the frame, size and position.
 174
 175 For all other help controllers, this function does nothing
 176 and just returns NULL.
 177
 178 \wxheading{Parameters}
 179
 180 \docparam{viewer}{This defaults to "netscape" for wxExtHelpController.}
 181
 182 \docparam{flags}{This defaults to wxHELP\_NETSCAPE for wxExtHelpController, indicating
 183 that the viewer is a variant of Netscape Navigator.}
 184
 185 \membersection{wxHelpController::KeywordSearch}\label{wxhelpcontrollerkeywordsearch}
 186
 187 \func{virtual bool}{KeywordSearch}{\param{const wxString\& }{keyWord}}
 188
 189 If the help viewer is not running, runs it, and searches for sections matching the given keyword. If one
 190 match is found, the file is displayed at this section.
 191
 192 {\it WinHelp, MS HTML Help:} If more than one match is found,
 193 the first topic is displayed.
 194
 195 {\it External HTML help, simple wxHTML help:} If more than one match is found,
 196 a choice of topics is displayed.
 197
 198 {\it wxHtmlHelpController:} see \helpref{wxHtmlHelpController::KeywordSearch}{wxhtmlhelpcontrollerkeywordsearch}.
 199
 200 \membersection{wxHelpController::LoadFile}\label{wxhelpcontrollerloadfile}
 201
 202 \func{virtual bool}{LoadFile}{\param{const wxString\& }{file = ""}}
 203
 204 If the help viewer is not running, runs it and loads the given file.
 205 If the filename is not supplied or is
 206 empty, the file specified in {\bf Initialize} is used. If the viewer is
 207 already displaying the specified file, it will not be reloaded. This
 208 member function may be used before each display call in case the user
 209 has opened another file.
 210
 211 wxHtmlHelpController ignores this call.
 212
 213 \membersection{wxHelpController::OnQuit}\label{wxhelpcontrolleronquit}
 214
 215 \func{virtual bool}{OnQuit}{\void}
 216
 217 Overridable member called when this application's viewer is quit by the user.
 218
 219 This does not work for all help controllers.
 220
 221 \membersection{wxHelpController::SetFrameParameters}\label{wxhelpcontrollersetframeparameters}
 222
 223 \func{virtual void}{SetFrameParameters}{\param{const wxString \& }{title},
 224  \param{const wxSize \& }{size}, \param{const wxPoint \& }{pos = wxDefaultPosition},
 225  \param{bool }{newFrameEachTime = false}}
 226
 227 For wxHtmlHelpController, the title is set (again with \%s indicating the
 228 page title) and also the size and position of the frame if the frame is already
 229 open. {\it newFrameEachTime} is ignored.
 230
 231 For all other help controllers this function has no effect.
 232
 233 \membersection{wxHelpController::SetViewer}\label{wxhelpcontrollersetviewer}
 234
 235 \func{virtual void}{SetViewer}{\param{const wxString\& }{viewer}, \param{long}{ flags}}
 236
 237 Sets detailed viewer information. So far this is only relevant to wxExtHelpController.
 238
 239 Some examples of usage:
 240
 241 \begin{verbatim}
 242   m_help.SetViewer("kdehelp");
 243   m_help.SetViewer("gnome-help-browser");
 244   m_help.SetViewer("netscape", wxHELP_NETSCAPE);
 245 \end{verbatim}
 246
 247 \membersection{wxHelpController::Quit}\label{wxhelpcontrollerquit}
 248
 249 \func{virtual bool}{Quit}{\void}
 250
 251 If the viewer is running, quits it by disconnecting.
 252
 253 For Windows Help, the viewer will only close if no other application is using it.
 254