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 you
  47 must add this line to your application initialization: \verb$wxFileSystem::AddHandler(new wxZipFSHandler);$
  48 or nothing will be shown in your help window.
  49 \end{itemize}
  50
  51 \wxheading{Derived from}
  52
  53 wxHelpControllerBase\\
  54 \helpref{wxObject}{wxobject}
  55
  56 \wxheading{Include files}
  57
  58 <wx/help.h> (wxWindows chooses the appropriate help controller class)\\
  59 <wx/helpbase.h> (wxHelpControllerBase class)\\
  60 <wx/helpwin.h> (Windows Help controller)\\
  61 <wx/msw/helpchm.h> (MS HTML Help controller)\\
  62 <wx/generic/helpext.h> (external HTML browser controller)\\
  63 <wx/html/helpctrl.h> (wxHTML based help controller: wxHtmlHelpController)
  64
  65 \wxheading{See also}
  66
  67 \helpref{wxHtmlHelpController}{wxhtmlhelpcontroller}, \helpref{wxHTML}{wxhtml}
  68
  69 \latexignore{\rtfignore{\wxheading{Members}}}
  70
  71 \membersection{wxHelpController::wxHelpController}
  72
  73 \func{}{wxHelpController}{\void}
  74
  75 Constructs a help instance object, but does not invoke the help viewer.
  76
  77 \membersection{wxHelpController::\destruct{wxHelpController}}
  78
  79 \func{}{\destruct{wxHelpController}}{\void}
  80
  81 Destroys the help instance, closing down the viewer if it is running.
  82
  83 \membersection{wxHelpController::Initialize}\label{wxhelpcontrollerinitialize}
  84
  85 \func{virtual void}{Initialize}{\param{const wxString\& }{file}}
  86
  87 \func{virtual void}{Initialize}{\param{const wxString\& }{file}, \param{int}{ server}}
  88
  89 Initializes the help instance with a help filename, and optionally a server socket
  90 number if using wxHelp (now obsolete). Does not invoke the help viewer.
  91 This must be called directly after the help instance object is created and before
  92 any attempts to communicate with the viewer.
  93
  94 You may omit the file extension and a suitable one will be chosen. For
  95 wxHtmlHelpController, the extensions zip, htb and hhp will be appended while searching for
  96 a suitable file. For WinHelp, the hlp extension is appended.
  97
  98 \membersection{wxHelpController::DisplayBlock}\label{wxhelpcontrollerdisplayblock}
  99
 100 \func{virtual bool}{DisplayBlock}{\param{long}{ blockNo}}
 101
 102 If the help viewer is not running, runs it and displays the file at the given block number.
 103
 104 {\it WinHelp:} Refers to the context number.
 105
 106 {\it MS HTML Help:} Refers to the context number.
 107
 108 {\it External HTML help:} the same as for \helpref{wxHelpController::DisplaySection}{wxhelpcontrollerdisplaysection}.
 109
 110 {\it wxHtmlHelpController:} {\it sectionNo} is an identifier as specified in the {\tt .hhc} file. See \helpref{Help files format}{helpformat}.
 111
 112 This function is for backward compatibility only, and applications should use \helpref{wxHelpController}{wxhelpcontrollerdisplaysection} instead.
 113
 114 \membersection{wxHelpController::DisplayContents}\label{wxhelpcontrollerdisplaycontents}
 115
 116 \func{virtual bool}{DisplayContents}{\void}
 117
 118 If the help viewer is not running, runs it and displays the
 119 contents.
 120
 121 \membersection{wxHelpController::DisplayContextPopup}\label{wxhelpcontrollerdisplaycontextpopup}
 122
 123 \func{virtual bool}{DisplayContextPopup}{\param{int }{contextId}}
 124
 125 Displays the section as a popup window using a context id.
 126
 127 Returns FALSE if unsuccessful or not implemented.
 128
 129 \membersection{wxHelpController::DisplaySection}\label{wxhelpcontrollerdisplaysection}
 130
 131 \func{virtual bool}{DisplaySection}{\param{const wxString\&}{ section}}
 132
 133 If the help viewer is not running, runs it and displays the given section.
 134
 135 The interpretation of {\it section} differs between help viewers. For most viewers,
 136 this call is equivalent to KeywordSearch. For MS HTML Help, wxHTML help and external HTML help,
 137 if {\it section} has a .htm
 138 or .html extension, that HTML file will be displayed; otherwise
 139 a keyword search is done.
 140
 141 \func{virtual bool}{DisplaySection}{\param{int}{ sectionNo}}
 142
 143 If the help viewer is not running, runs it and displays the given section.
 144
 145 {\it WinHelp, MS HTML Help} {\it sectionNo} is a context id.
 146
 147 {\it External HTML help:} wxExtHelpController implements {\it sectionNo} as an id in a map file, which is of the form:
 148
 149 \begin{verbatim}
 150 0  wx.html             ; Index
 151 1  wx34.html#classref  ; Class reference
 152 2  wx204.html          ; Function reference
 153 \end{verbatim}
 154
 155 {\it wxHtmlHelpController:} {\it sectionNo} is an identifier as specified in the {\tt .hhc} file. See \helpref{Help files format}{helpformat}.
 156
 157 See also the help sample for notes on how to specify section numbers for various help file formats.
 158
 159 \membersection{wxHelpController::DisplayTextPopup}\label{wxhelpcontrollerdisplaytextpopup}
 160
 161 \func{virtual bool}{DisplayTextPopup}{\param{const wxString\&}{ text}, \param{const wxPoint\& }{pos}}
 162
 163 Displays the text in a popup window, if possible.
 164
 165 Returns FALSE if unsuccessful or not implemented.
 166
 167 \membersection{wxHelpController::GetFrameParameters}\label{wxhelpcontrollergetframeparameters}
 168
 169 \func{virtual wxFrame *}{GetFrameParameters}{\param{const wxSize * }{size = NULL}, \param{const wxPoint * }{pos = NULL},
 170  \param{bool *}{newFrameEachTime = NULL}}
 171
 172 wxHtmlHelpController returns the frame, size and position.
 173
 174 For all other help controllers, this function does nothing
 175 and just returns NULL.
 176
 177 \wxheading{Parameters}
 178
 179 \docparam{viewer}{This defaults to "netscape" for wxExtHelpController.}
 180
 181 \docparam{flags}{This defaults to wxHELP\_NETSCAPE for wxExtHelpController, indicating
 182 that the viewer is a variant of Netscape Navigator.}
 183
 184 \membersection{wxHelpController::KeywordSearch}\label{wxhelpcontrollerkeywordsearch}
 185
 186 \func{virtual bool}{KeywordSearch}{\param{const wxString\& }{keyWord}}
 187
 188 If the help viewer is not running, runs it, and searches for sections matching the given keyword. If one
 189 match is found, the file is displayed at this section.
 190
 191 {\it WinHelp, MS HTML Help:} If more than one match is found,
 192 the first topic is displayed.
 193
 194 {\it External HTML help, simple wxHTML help:} If more than one match is found,
 195 a choice of topics is displayed.
 196
 197 {\it wxHtmlHelpController:} see \helpref{wxHtmlHelpController::KeywordSearch}{wxhtmlhelpcontrollerkeywordsearch}.
 198
 199 \membersection{wxHelpController::LoadFile}\label{wxhelpcontrollerloadfile}
 200
 201 \func{virtual bool}{LoadFile}{\param{const wxString\& }{file = ""}}
 202
 203 If the help viewer is not running, runs it and loads the given file.
 204 If the filename is not supplied or is
 205 empty, the file specified in {\bf Initialize} is used. If the viewer is
 206 already displaying the specified file, it will not be reloaded. This
 207 member function may be used before each display call in case the user
 208 has opened another file.
 209
 210 wxHtmlHelpController ignores this call.
 211
 212 \membersection{wxHelpController::OnQuit}\label{wxhelpcontrolleronquit}
 213
 214 \func{virtual bool}{OnQuit}{\void}
 215
 216 Overridable member called when this application's viewer is quit by the user.
 217
 218 This does not work for all help controllers.
 219
 220 \membersection{wxHelpController::SetFrameParameters}\label{wxhelpcontrollersetframeparameters}
 221
 222 \func{virtual void}{SetFrameParameters}{\param{const wxString \& }{title},
 223  \param{const wxSize \& }{size}, \param{const wxPoint \& }{pos = wxDefaultPosition},
 224  \param{bool }{newFrameEachTime = FALSE}}
 225
 226 For wxHtmlHelpController, the title is set (again with \%s indicating the
 227 page title) and also the size and position of the frame if the frame is already
 228 open. {\it newFrameEachTime} is ignored.
 229
 230 For all other help controllers this function has no effect.
 231
 232 \membersection{wxHelpController::SetViewer}\label{wxhelpcontrollersetviewer}
 233
 234 \func{virtual void}{SetViewer}{\param{const wxString\& }{viewer}, \param{long}{ flags}}
 235
 236 Sets detailed viewer information. So far this is only relevant to wxExtHelpController.
 237
 238 Some examples of usage:
 239
 240 \begin{verbatim}
 241   m_help.SetViewer("kdehelp");
 242   m_help.SetViewer("gnome-help-browser");
 243   m_help.SetViewer("netscape", wxHELP_NETSCAPE);
 244 \end{verbatim}
 245
 246 \membersection{wxHelpController::Quit}\label{wxhelpcontrollerquit}
 247
 248 \func{virtual bool}{Quit}{\void}
 249
 250 If the viewer is running, quits it by disconnecting.
 251
 252 For Windows Help, the viewer will only close if no other application is using it.
 253