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, wxHelpControllerHtml 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 classess 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 neccessary 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 wxHelpControllerHtml, using \helpref{wxHTML}{wxhtml} to display help. See {\tt wx/helpwxht.h} for
  44 details of use.
  45 \item \helpref{wxHtmlHelpController}{wxhtmlhelpcontroller}, a more sophisticated help controller using \helpref{wxHTML}{wxhtml}, in
  46 a similar style to the Microsoft HTML Help viewer and using some of the same files.
  47 Although it has an API compatible with other help controllers, it has more advanced features, so it is
  48 recommended that you use the specific API for this class instead.
  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/generic/helpwxht.h> (simple wxHTML-based help controller)\\
  64 <wx/html/helpctrl.h> (advanced 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. For wxHelpControllerHtml (the
  98 standard HTML help controller), the filename is assumed to be a directory containing
  99 the HTML files.
 100
 101 \membersection{wxHelpController::DisplayBlock}\label{wxhelpcontrollerdisplayblock}
 102
 103 \func{virtual bool}{DisplayBlock}{\param{long}{ blockNo}}
 104
 105 If the help viewer is not running, runs it and displays the file at the given block number.
 106
 107 {\it WinHelp:} Refers to the context number.
 108
 109 {\it MS HTML Help:} Refers to the context number.
 110
 111 {\it External HTML help:} the same as for \helpref{wxHelpController::DisplaySection}{wxhelpcontrollerdisplaysection}.
 112
 113 {\it wxHtmlHelpController:} {\it sectionNo} is an identifier as specified in the {\tt .hhc} file. See \helpref{Help files format}{helpformat}.
 114
 115 This function is for backward compatibility only, and applications should use \helpref{wxHelpController}{wxhelpcontrollerdisplaysection} instead.
 116
 117 \membersection{wxHelpController::DisplayContents}\label{wxhelpcontrollerdisplaycontents}
 118
 119 \func{virtual bool}{DisplayContents}{\void}
 120
 121 If the help viewer is not running, runs it and displays the
 122 contents.
 123
 124 \membersection{wxHelpController::DisplayContextPopup}\label{wxhelpcontrollerdisplaycontextpopup}
 125
 126 \func{virtual bool}{DisplayContextPopup}{\param{int }{contextId}}
 127
 128 Displays the section as a popup window using a context id.
 129
 130 Returns FALSE if unsuccessful or not implemented.
 131
 132 \membersection{wxHelpController::DisplaySection}\label{wxhelpcontrollerdisplaysection}
 133
 134 \func{virtual bool}{DisplaySection}{\param{const wxString\&}{ section}}
 135
 136 If the help viewer is not running, runs it and displays the given section.
 137
 138 The interpretation of {\it section} differs between help viewers. For most viewers,
 139 this call is equivalent to KeywordSearch. For MS HTML Help, external HTML help
 140 and simple wxHTML help, if {\it section} has a .htm
 141 or .html extension, that HTML file will be displayed; otherwise
 142 a keyword search is done.
 143
 144 \func{virtual bool}{DisplaySection}{\param{int}{ sectionNo}}
 145
 146 If the help viewer is not running, runs it and displays the given section.
 147
 148 {\it WinHelp, MS HTML Help:} {\it sectionNo} is a context id.
 149
 150 {\it External HTML help/simple wxHTML help:} wxExtHelpController and wxHelpControllerHtml implement {\it sectionNo} as an id in a map file, which is of the form:
 151
 152 \begin{verbatim}
 153 0  wx.html             ; Index
 154 1  wx34.html#classref  ; Class reference
 155 2  wx204.html          ; Function reference
 156 \end{verbatim}
 157
 158 {\it wxHtmlHelpController:} {\it sectionNo} is an identifier as specified in the {\tt .hhc} file. See \helpref{Help files format}{helpformat}.
 159
 160 See also the help sample for notes on how to specify section numbers for various help file formats.
 161
 162 \membersection{wxHelpController::DisplayTextPopup}\label{wxhelpcontrollerdisplaytextpopup}
 163
 164 \func{virtual bool}{DisplayTextPopup}{\param{const wxString\&}{ text}, \param{const wxPoint\& }{pos}}
 165
 166 Displays the text in a popup window, if possible.
 167
 168 Returns FALSE if unsuccessful or not implemented.
 169
 170 \membersection{wxHelpController::GetFrameParameters}\label{wxhelpcontrollergetframeparameters}
 171
 172 \func{virtual wxFrame *}{GetFrameParameters}{\param{const wxSize * }{size = NULL}, \param{const wxPoint * }{pos = NULL},
 173  \param{bool *}{newFrameEachTime = NULL}}
 174
 175 This reads the current settings for the help frame in the case of the
 176 wxHelpControllerHtml, setting the frame size, position and
 177 the newFrameEachTime parameters to the last values used. It also
 178 returns the pointer to the last opened help frame. This can be used
 179 for example, to automatically close the help frame on program
 180 shutdown.
 181
 182 wxHtmlHelpController returns the frame,
 183 size and position.
 184
 185 For all other help controllers, this function does nothing
 186 and just returns NULL.
 187
 188 \wxheading{Parameters}
 189
 190 \docparam{viewer}{This defaults to "netscape" for wxExtHelpController.}
 191
 192 \docparam{flags}{This defaults to wxHELP\_NETSCAPE for wxExtHelpController, indicating
 193 that the viewer is a variant of Netscape Navigator.}
 194
 195 \membersection{wxHelpController::KeywordSearch}\label{wxhelpcontrollerkeywordsearch}
 196
 197 \func{virtual bool}{KeywordSearch}{\param{const wxString\& }{keyWord}}
 198
 199 If the help viewer is not running, runs it, and searches for sections matching the given keyword. If one
 200 match is found, the file is displayed at this section.
 201
 202 {\it WinHelp, MS HTML Help:} If more than one match is found,
 203 the first topic is displayed.
 204
 205 {\it External HTML help, simple wxHTML help:} If more than one match is found,
 206 a choice of topics is displayed.
 207
 208 {\it wxHtmlHelpController:} see \helpref{wxHtmlHelpController::KeywordSearch}{wxhtmlhelpcontrollerkeywordsearch}.
 209
 210 \membersection{wxHelpController::LoadFile}\label{wxhelpcontrollerloadfile}
 211
 212 \func{virtual bool}{LoadFile}{\param{const wxString\& }{file = ""}}
 213
 214 If the help viewer is not running, runs it and loads the given file.
 215 If the filename is not supplied or is
 216 empty, the file specified in {\bf Initialize} is used. If the viewer is
 217 already displaying the specified file, it will not be reloaded. This
 218 member function may be used before each display call in case the user
 219 has opened another file.
 220
 221 wxHtmlHelpController ignores this call.
 222
 223 \membersection{wxHelpController::OnQuit}\label{wxhelpcontrolleronquit}
 224
 225 \func{virtual bool}{OnQuit}{\void}
 226
 227 Overridable member called when this application's viewer is quit by the user.
 228
 229 This does not work for all help controllers.
 230
 231 \membersection{wxHelpController::SetFrameParameters}\label{wxhelpcontrollersetframeparameters}
 232
 233 \func{virtual void}{SetFrameParameters}{\param{const wxString \& }{title},
 234  \param{const wxSize \& }{size}, \param{const wxPoint \& }{pos = wxDefaultPosition},
 235  \param{bool }{newFrameEachTime = FALSE}}
 236
 237 For wxHelpControllerHtml, this allows the application to set the
 238 default frame title, size and position for the frame. If the title
 239 contains \%s, this will be replaced with the page title. If the
 240 parameter newFrameEachTime is set, the controller will open a new
 241 help frame each time it is called.
 242
 243 For wxHtmlHelpController, the title is set (again with \%s indicating the
 244 page title) and also the size and position of the frame if the frame is already
 245 open. {\it newFrameEachTime} is ignored.
 246
 247 For all other help controllers this function has no effect.
 248
 249 \membersection{wxHelpController::SetViewer}\label{wxhelpcontrollersetviewer}
 250
 251 \func{virtual void}{SetViewer}{\param{const wxString\& }{viewer}, \param{long}{ flags}}
 252
 253 Sets detailed viewer information. So far this is only relevant to wxExtHelpController.
 254
 255 Some examples of usage:
 256
 257 \begin{verbatim}
 258   m_help.SetViewer("kdehelp");
 259   m_help.SetViewer("gnome-help-browser");
 260   m_help.SetViewer("netscape", wxHELP_NETSCAPE);
 261 \end{verbatim}
 262
 263 \membersection{wxHelpController::Quit}\label{wxhelpcontrollerquit}
 264
 265 \func{virtual bool}{Quit}{\void}
 266
 267 If the viewer is running, quits it by disconnecting.
 268
 269 For Windows Help, the viewer will only close if no other application is using it.
 270