Doc/mac/libmacui.tex

   1 \section{\module{EasyDialogs} ---
   2          Basic Macintosh dialogs}
   3
   4 \declaremodule{standard}{EasyDialogs}
   5   \platform{Mac}
   6 \modulesynopsis{Basic Macintosh dialogs.}
   7
   8 The \module{EasyDialogs} module contains some simple dialogs for the
   9 Macintosh. All routines take an optional resource ID parameter \var{id}
  10 with which one can override the \constant{DLOG} resource used for the
  11 dialog, provided that the dialog items correspond (both type and item
  12 number) to those in the default \constant{DLOG} resource. See source
  13 code for details.
  14
  15 The \module{EasyDialogs} module defines the following functions:
  16
  17
  18 \begin{funcdesc}{Message}{str\optional{, id\optional{, ok=None}}}
  19 Displays a modal dialog with the message text \var{str}, which should be
  20 at most 255 characters long. The button text defaults to ``OK'', but is
  21 set to the string argument \var{ok} if the latter is supplied. Control
  22 is returned when the user clicks the ``OK'' button.
  23 \end{funcdesc}
  24
  25
  26 \begin{funcdesc}{AskString}{prompt\optional{, default\optional{,
  27     id\optional{, ok\optional{, cancel}}}}}
  28 Asks the user to input a string value via a modal dialog. \var{prompt}
  29 is the prompt message, and the optional \var{default} supplies the
  30 initial value for the string (otherwise \code{""} is used). The text of
  31 the ``OK'' and ``Cancel'' buttons can be changed with the \var{ok} and
  32 \var{cancel} arguments. All strings can be at most 255 bytes long.
  33 \function{AskString()} returns the string entered or \code{None} in case
  34 the user cancelled.
  35 \end{funcdesc}
  36
  37
  38 \begin{funcdesc}{AskPassword}{prompt\optional{, default\optional{,
  39     id\optional{, ok\optional{, cancel}}}}}
  40 Asks the user to input a string value via a modal dialog. Like
  41 \function{AskString()}, but with the text shown as bullets. The
  42 arguments have the same meaning as for \function{AskString()}.
  43 \end{funcdesc}
  44
  45
  46 \begin{funcdesc}{AskYesNoCancel}{question\optional{, default\optional{,
  47     yes\optional{, no\optional{, cancel\optional{, id}}}}}}
  48 Presents a dialog with prompt \var{question} and three buttons labelled
  49 ``Yes'', ``No'', and ``Cancel''. Returns \code{1} for ``Yes'', \code{0}
  50 for ``No'' and \code{-1} for ``Cancel''. The value of \var{default} (or
  51 \code{0} if \var{default} is not supplied) is returned when the
  52 \kbd{RETURN} key is pressed. The text of the buttons can be changed with
  53 the \var{yes}, \var{no}, and \var{cancel} arguments; to prevent a button
  54 from appearing, supply \code{""} for the corresponding argument.
  55 \end{funcdesc}
  56
  57
  58 \begin{funcdesc}{ProgressBar}{\optional{title\optional{, maxval\optional{,
  59     label\optional{, id}}}}}
  60 Displays a modeless progress-bar dialog. This is the constructor for the
  61 \class{ProgressBar} class described below. \var{title} is the text
  62 string displayed (default ``Working...''), \var{maxval} is the value at
  63 which progress is complete (default \code{0}, indicating that an
  64 indeterminate amount of work remains to be done), and \var{label} is
  65 the text that is displayed above the progress bar itself.
  66 \end{funcdesc}
  67
  68
  69 \begin{funcdesc}{GetArgv}{\optional{optionlist\optional{
  70     commandlist\optional{, addoldfile\optional{, addnewfile\optional{,
  71     addfolder\optional{, id}}}}}}}
  72 Displays a dialog which aids the user in constructing a command-line
  73 argument list.  Returns the list in \code{sys.argv} format, suitable for
  74 passing as an argument to \function{getopt.getopt()}.  \var{addoldfile},
  75 \var{addnewfile}, and \var{addfolder} are boolean arguments.  When
  76 nonzero, they enable the user to insert into the command line paths to
  77 an existing file, a (possibly) not-yet-existent file, and a folder,
  78 respectively.  (Note: Option arguments must appear in the command line
  79 before file and folder arguments in order to be recognized by
  80 \function{getopt.getopt()}.)  Arguments containing spaces can be
  81 specified by enclosing them within single or double quotes.  A
  82 \exception{SystemExit} exception is raised if the user presses the
  83 ``Cancel'' button.
  84
  85 \var{optionlist} is a list that determines a popup menu from which the
  86 allowed options are selected.  Its items can take one of two forms:
  87 \var{optstr} or \code{(\var{optstr}, \var{descr})}.  When present,
  88 \var{descr} is a short descriptive string that is displayed in the
  89 dialog while this option is selected in the popup menu.  The
  90 correspondence between \var{optstr}s and command-line arguments is:
  91
  92 \begin{tableii}{l|l}{textrm}{\var{optstr} format}{Command-line format}
  93 \lineii{\code{x}}
  94        {\programopt{-x} (short option)}
  95 \lineii{\code{x:} or \code{x=}}
  96        {\programopt{-x} (short option with value)}
  97 \lineii{\code{xyz}}
  98        {\longprogramopt{xyz} (long option)}
  99 \lineii{\code{xyz:} or \code{xyz=}}
 100        {\longprogramopt{xyz} (long option with value)}
 101 \end{tableii}
 102
 103 \var{commandlist} is a list of items of the form \var{cmdstr} or
 104 \code{(\var{cmdstr}, \var{descr})}, where \var{descr} is as above.  The
 105 \var{cmdstr}s will appear in a popup menu.  When chosen, the text of
 106 \var{cmdstr} will be appended to the command line as is, except that a
 107 trailing \character{:} or \character{=} (if present) will be trimmed
 108 off.
 109
 110 \versionadded{2.0}
 111 \end{funcdesc}
 112
 113
 114
 115 \subsection{ProgressBar Objects \label{progressbar-objects}}
 116
 117 \class{ProgressBar} objects provide support for modeless progress-bar
 118 dialogs.  Both determinate (thermometer style) and indeterminate
 119 (barber-pole style) progress bars are supported.  The bar will be
 120 determinate if its maximum value is greater than zero; otherwise it
 121 will be indeterminate.
 122 \versionchanged[Support for indeterminate-style progress bars was
 123                 added]{2.2}
 124
 125 The dialog is displayed immediately after creation. If the dialog's
 126 ``Cancel'' button is pressed, or if \kbd{Cmd-.} or \kbd{ESC} is typed,
 127 the dialog window is hidden and \exception{KeyboardInterrupt} is
 128 raised (but note that this response does not occur until the progress
 129 bar is next updated, typically via a call to \method{inc()} or
 130 \method{set()}).  Otherwise, the bar remains visible until the
 131 \class{ProgressBar} object is discarded.
 132
 133 \class{ProgressBar} objects possess the following attributes and
 134 methods:
 135
 136 \begin{memberdesc}[ProgressBar]{curval}
 137 The current value (of type integer or long integer) of the progress
 138 bar.  The normal access methods coerce \member{curval} between
 139 \code{0} and \member{maxval}.  This attribute should not be altered
 140 directly.
 141 \end{memberdesc}
 142
 143 \begin{memberdesc}[ProgressBar]{maxval}
 144 The maximum value (of type integer or long integer) of the progress
 145 bar; the progress bar (thermometer style) is full when \member{curval}
 146 equals \member{maxval}.  If \member{maxval} is \code{0}, the bar will
 147 be indeterminate (barber-pole).  This attribute should not be altered
 148 directly.
 149 \end{memberdesc}
 150
 151 \begin{methoddesc}[ProgressBar]{title}{\optional{newstr}}
 152 Sets the text in the title bar of the progress dialog to
 153 \var{newstr}.
 154 \end{methoddesc}
 155
 156 \begin{methoddesc}[ProgressBar]{label}{\optional{newstr}}
 157 Sets the text in the progress box of the progress dialog to
 158 \var{newstr}.
 159 \end{methoddesc}
 160
 161 \begin{methoddesc}[ProgressBar]{set}{value\optional{, max}}
 162 Sets the progress bar's \member{curval} to \var{value}, and also
 163 \member{maxval} to \var{max} if the latter is provided.  \var{value}
 164 is first coerced between 0 and \member{maxval}.  The thermometer bar
 165 is updated to reflect the changes, including a change from
 166 indeterminate to determinate or vice versa.
 167 \end{methoddesc}
 168
 169 \begin{methoddesc}[ProgressBar]{inc}{\optional{n}}
 170 Increments the progress bar's \member{curval} by \var{n}, or by \code{1}
 171 if \var{n} is not provided.  (Note that \var{n} may be negative, in
 172 which case the effect is a decrement.)  The progress bar is updated to
 173 reflect the change.  If the bar is indeterminate, this causes one
 174 ``spin'' of the barber pole.  The resulting \member{curval} is coerced
 175 between 0 and \member{maxval} if incrementing causes it to fall
 176 outside this range.
 177 \end{methoddesc}