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 desktop Windows, wxCHMHelpController is used (MS HTML Help).
  22 \item On Windows CE, wxWinceHelpController is used.
  23 \item On all other platforms, wxHtmlHelpController is used if wxHTML is
  24 compiled into wxWidgets; otherwise wxExtHelpController is used (for invoking an external
  25 browser).
  26 \end{itemize}
  27
  28 The remaining help controller classes need to be named
  29 explicitly by an application that wishes to make use of them.
  30
  31 There are currently the following help controller classes defined:
  32
  33 \begin{itemize}\itemsep=0pt
  34 \item wxWinHelpController, for controlling Windows Help.
  35 \item wxCHMHelpController, for controlling MS HTML Help. To use this, you need to set wxUSE\_MS\_HTML\_HELP
  36 to 1 in setup.h and have htmlhelp.h header from Microsoft's HTML Help kit (you don't need
  37 VC++ specific htmlhelp.lib because wxWidgets loads necessary DLL at runtime and so it
  38 works with all compilers).
  39 \item wxBestHelpController, for controlling MS HTML Help or, if Microsoft's runtime is
  40 not available, \helpref{wxHtmlHelpController}{wxhtmlhelpcontroller}. You need to provide
  41 {\bf both} CHM and HTB versions of the help file. For 32bit Windows only.
  42 \item wxExtHelpController, for controlling external browsers under Unix.
  43 The default browser is Netscape Navigator. The 'help' sample shows its use.
  44 \item wxWinceHelpController, for controlling a simple {\tt .htm} help controller for Windows CE applications.
  45 \item \helpref{wxHtmlHelpController}{wxhtmlhelpcontroller}, a 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. Note that if you
  49 use .zip or .htb formats for your books, you
  50 must add this line to your application initialization: {\tt wxFileSystem::AddHandler(new wxZipFSHandler);}
  51 or nothing will be shown in your help window.
  52 \end{itemize}
  53
  54 \wxheading{Derived from}
  55
  56 wxHelpControllerBase\\
  57 \helpref{wxObject}{wxobject}
  58
  59 \wxheading{Include files}
  60
  61 <wx/help.h> (wxWidgets chooses the appropriate help controller class)\\
  62 <wx/helpbase.h> (wxHelpControllerBase class)\\
  63 <wx/helpwin.h> (Windows Help controller)\\
  64 <wx/msw/helpchm.h> (MS HTML Help controller)\\
  65 <wx/generic/helpext.h> (external HTML browser controller)\\
  66 <wx/html/helpctrl.h> (wxHTML based help controller: wxHtmlHelpController)
  67
  68 \wxheading{See also}
  69
  70 \helpref{wxHtmlHelpController}{wxhtmlhelpcontroller}, \helpref{wxHTML}{wxhtml}
  71
  72 \latexignore{\rtfignore{\wxheading{Members}}}
  73
  74 \membersection{wxHelpController::wxHelpController}\label{wxhelpcontrollerctor}
  75
  76 \func{}{wxHelpController}{\param{wxWindow*}{ parentWindow = NULL}}
  77
  78 Constructs a help instance object, but does not invoke the help viewer.
  79
  80 If you provide a window, it will be used by some help controller classes, such as
  81 wxCHMHelpController, wxWinHelpController and wxHtmlHelpController, as the
  82 parent for the help window instead of the value of \helpref{wxApp::GetTopWindow}{wxappgettopwindow}. You can also change the parent window later with
  83 \helpref{wxHelpController::SetParentWindow}{wxhelpcontrollersetparentwindow}.
  84
  85 \membersection{wxHelpController::\destruct{wxHelpController}}\label{wxhelpcontrollerdtor}
  86
  87 \func{}{\destruct{wxHelpController}}{\void}
  88
  89 Destroys the help instance, closing down the viewer if it is running.
  90
  91 \membersection{wxHelpController::Initialize}\label{wxhelpcontrollerinitialize}
  92
  93 \func{virtual bool}{Initialize}{\param{const wxString\& }{file}}
  94
  95 \func{virtual bool}{Initialize}{\param{const wxString\& }{file}, \param{int}{ server}}
  96
  97 Initializes the help instance with a help filename, and optionally a server socket
  98 number if using wxHelp (now obsolete). Does not invoke the help viewer.
  99 This must be called directly after the help instance object is created and before
 100 any attempts to communicate with the viewer.
 101
 102 You may omit the file extension and a suitable one will be chosen. For
 103 wxHtmlHelpController, the extensions zip, htb and hhp will be appended while searching for
 104 a suitable file. For WinHelp, the hlp extension is appended.
 105
 106 \membersection{wxHelpController::DisplayBlock}\label{wxhelpcontrollerdisplayblock}
 107
 108 \func{virtual bool}{DisplayBlock}{\param{long}{ blockNo}}
 109
 110 If the help viewer is not running, runs it and displays the file at the given block number.
 111
 112 {\it WinHelp:} Refers to the context number.
 113
 114 {\it MS HTML Help:} Refers to the context number.
 115
 116 {\it External HTML help:} the same as for \helpref{wxHelpController::DisplaySection}{wxhelpcontrollerdisplaysection}.
 117
 118 {\it wxHtmlHelpController:} {\it sectionNo} is an identifier as specified in the {\tt .hhc} file. See \helpref{Help files format}{helpformat}.
 119
 120 This function is for backward compatibility only, and applications should use \helpref{wxHelpController}{wxhelpcontrollerdisplaysection} instead.
 121
 122 \membersection{wxHelpController::DisplayContents}\label{wxhelpcontrollerdisplaycontents}
 123
 124 \func{virtual bool}{DisplayContents}{\void}
 125
 126 If the help viewer is not running, runs it and displays the
 127 contents.
 128
 129 \membersection{wxHelpController::DisplayContextPopup}\label{wxhelpcontrollerdisplaycontextpopup}
 130
 131 \func{virtual bool}{DisplayContextPopup}{\param{int }{contextId}}
 132
 133 Displays the section as a popup window using a context id.
 134
 135 Returns false if unsuccessful or not implemented.
 136
 137 \membersection{wxHelpController::DisplaySection}\label{wxhelpcontrollerdisplaysection}
 138
 139 \func{virtual bool}{DisplaySection}{\param{const wxString\&}{ section}}
 140
 141 If the help viewer is not running, runs it and displays the given section.
 142
 143 The interpretation of {\it section} differs between help viewers. For most viewers,
 144 this call is equivalent to KeywordSearch. For MS HTML Help, wxHTML help and external HTML help,
 145 if {\it section} has a .htm
 146 or .html extension, that HTML file will be displayed; otherwise
 147 a keyword search is done.
 148
 149 \func{virtual bool}{DisplaySection}{\param{int}{ sectionNo}}
 150
 151 If the help viewer is not running, runs it and displays the given section.
 152
 153 {\it WinHelp, MS HTML Help} {\it sectionNo} is a context id.
 154
 155 {\it External HTML help:} wxExtHelpController implements {\it sectionNo} as an id in a map file, which is of the form:
 156
 157 \begin{verbatim}
 158 0  wx.html             ; Index
 159 1  wx34.html#classref  ; Class reference
 160 2  wx204.html          ; Function reference
 161 \end{verbatim}
 162
 163 {\it wxHtmlHelpController:} {\it sectionNo} is an identifier as specified in the {\tt .hhc} file. See \helpref{Help files format}{helpformat}.
 164
 165 See also the help sample for notes on how to specify section numbers for various help file formats.
 166
 167 \membersection{wxHelpController::DisplayTextPopup}\label{wxhelpcontrollerdisplaytextpopup}
 168
 169 \func{virtual bool}{DisplayTextPopup}{\param{const wxString\&}{ text}, \param{const wxPoint\& }{pos}}
 170
 171 Displays the text in a popup window, if possible.
 172
 173 Returns false if unsuccessful or not implemented.
 174
 175 \membersection{wxHelpController::GetFrameParameters}\label{wxhelpcontrollergetframeparameters}
 176
 177 \func{virtual wxFrame *}{GetFrameParameters}{\param{const wxSize * }{size = NULL}, \param{const wxPoint * }{pos = NULL},
 178  \param{bool *}{newFrameEachTime = NULL}}
 179
 180 wxHtmlHelpController returns the frame, size and position.
 181
 182 For all other help controllers, this function does nothing
 183 and just returns NULL.
 184
 185 \wxheading{Parameters}
 186
 187 \docparam{viewer}{This defaults to "netscape" for wxExtHelpController.}
 188
 189 \docparam{flags}{This defaults to wxHELP\_NETSCAPE for wxExtHelpController, indicating
 190 that the viewer is a variant of Netscape Navigator.}
 191
 192 \membersection{wxHelpController::GetParentWindow}\label{wxhelpcontrollergetparentwindow}
 193
 194 \constfunc{virtual bool}{GetParentWindow}{\void}
 195
 196 Returns the window to be used as the parent for the help window. This window is used
 197 by wxCHMHelpController, wxWinHelpController and wxHtmlHelpController.
 198
 199 \membersection{wxHelpController::KeywordSearch}\label{wxhelpcontrollerkeywordsearch}
 200
 201 \func{virtual bool}{KeywordSearch}{\param{const wxString\& }{keyWord}, \param{wxHelpSearchMode }{mode = wxHELP\_SEARCH\_ALL}}
 202
 203 If the help viewer is not running, runs it, and searches for sections matching
 204 the given keyword. If one match is found, the file is displayed at this
 205 section. The optional parameter allows the search the index
 206 (wxHELP\_SEARCH\_INDEX) but this currently only supported by the
 207 wxHtmlHelpController.
 208
 209 {\it WinHelp, MS HTML Help:} If more than one match is found,
 210 the first topic is displayed.
 211
 212 {\it External HTML help, simple wxHTML help:} If more than one match is found,
 213 a choice of topics is displayed.
 214
 215 {\it wxHtmlHelpController:} see \helpref{wxHtmlHelpController::KeywordSearch}{wxhtmlhelpcontrollerkeywordsearch}.
 216
 217 \membersection{wxHelpController::LoadFile}\label{wxhelpcontrollerloadfile}
 218
 219 \func{virtual bool}{LoadFile}{\param{const wxString\& }{file = ""}}
 220
 221 If the help viewer is not running, runs it and loads the given file.
 222 If the filename is not supplied or is
 223 empty, the file specified in {\bf Initialize} is used. If the viewer is
 224 already displaying the specified file, it will not be reloaded. This
 225 member function may be used before each display call in case the user
 226 has opened another file.
 227
 228 wxHtmlHelpController ignores this call.
 229
 230 \membersection{wxHelpController::OnQuit}\label{wxhelpcontrolleronquit}
 231
 232 \func{virtual bool}{OnQuit}{\void}
 233
 234 Overridable member called when this application's viewer is quit by the user.
 235
 236 This does not work for all help controllers.
 237
 238 \membersection{wxHelpController::SetFrameParameters}\label{wxhelpcontrollersetframeparameters}
 239
 240 \func{virtual void}{SetFrameParameters}{\param{const wxString \& }{title},
 241  \param{const wxSize \& }{size}, \param{const wxPoint \& }{pos = wxDefaultPosition},
 242  \param{bool }{newFrameEachTime = false}}
 243
 244 For wxHtmlHelpController, the title is set (again with \%s indicating the
 245 page title) and also the size and position of the frame if the frame is already
 246 open. {\it newFrameEachTime} is ignored.
 247
 248 For all other help controllers this function has no effect.
 249
 250 \membersection{wxHelpController::SetParentWindow}\label{wxhelpcontrollersetparentwindow}
 251
 252 \func{virtual void}{SetParentWindow}{\param{wxWindow* }{parentWindow}}
 253
 254 Sets the window to be used as the parent for the help window. This is used
 255 by wxCHMHelpController, wxWinHelpController and wxHtmlHelpController.
 256
 257 \membersection{wxHelpController::SetViewer}\label{wxhelpcontrollersetviewer}
 258
 259 \func{virtual void}{SetViewer}{\param{const wxString\& }{viewer}, \param{long}{ flags}}
 260
 261 Sets detailed viewer information. So far this is only relevant to wxExtHelpController.
 262
 263 Some examples of usage:
 264
 265 \begin{verbatim}
 266   m_help.SetViewer("kdehelp");
 267   m_help.SetViewer("gnome-help-browser");
 268   m_help.SetViewer("netscape", wxHELP_NETSCAPE);
 269 \end{verbatim}
 270
 271 \membersection{wxHelpController::Quit}\label{wxhelpcontrollerquit}
 272
 273 \func{virtual bool}{Quit}{\void}
 274
 275 If the viewer is running, quits it by disconnecting.
 276
 277 For Windows Help, the viewer will only close if no other application is using it.
 278