@c Copyright (C) 2012 Rik Wehbring
@c
@c This file is part of Octave.
@c
@c Octave is free software; you can redistribute it and/or modify it
@c under the terms of the GNU General Public License as published by the
@c Free Software Foundation; either version 3 of the License, or (at
@c your option) any later version.
@c 
@c Octave is distributed in the hope that it will be useful, but WITHOUT
@c ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
@c FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
@c for more details.
@c 
@c You should have received a copy of the GNU General Public License
@c along with Octave; see the file COPYING.  If not, see
@c <http://www.gnu.org/licenses/>.

@node GUI Development
@chapter GUI Development

Octave is principally a batch or command-line language.  However, it does
offer some limited features for constructing graphical interfaces for
interacting with users.

The GUI elements available are I/O dialogs and a progress bar.  For example,
rather than hardcoding a filename for output results a script can open a dialog
box and allow the user to choose a file.  Similarly, if a calculation is
expected to take a long time a script can display a progress bar.

Several utility functions make it possible to store private data for use with
a GUI which will not pollute the user's variable space.

Finally, a program written in Octave might want to have long term storage of
preferences or state variables.  This can be done with user-defined
preferences.

@menu
* I/O Dialogs::       
* Progress Bar::       
* GUI Utility Functions::       
* User-Defined Preferences::       
@end menu

@node I/O Dialogs
@section I/O Dialogs

Simple dialog menus are available for choosing directories or files.  They
return a string variable which can then be used with any command requiring
a file name.

@DOCSTRING(uigetdir)

@DOCSTRING(uigetfile)

@DOCSTRING(uiputfile)

@node Progress Bar
@section Progress Bar
@cindex Progress Bar

@DOCSTRING(waitbar)

@node GUI Utility Functions
@section GUI Utility Functions

These functions do not implement a GUI element but are useful when developing
programs that do.  @strong{Warning:} The functions @code{uiwait},
@code{uiresume}, and @code{waitfor} are only available for the FLTK tooolkit.

@DOCSTRING(guidata)

@DOCSTRING(guihandles)

@DOCSTRING(uiwait)

@DOCSTRING(uiresume)

@DOCSTRING(waitfor)

@node User-Defined Preferences
@section User-Defined Preferences

@DOCSTRING(addpref)

@DOCSTRING(getpref)

@DOCSTRING(ispref)

@DOCSTRING(rmpref)

@DOCSTRING(setpref)