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<html><head><title>The Optionmenu Widget (Perl in a Nutshell, 2nd Edition)</title><link rel="stylesheet" type="text/css" href="../style/style1.css" /><meta name="DC.Creator" content="Stephen Spainhour" /><meta name="DC.Format" content="text/xml" scheme="MIME" /><meta name="DC.Language" content="en-US" /><meta name="DC.Publisher" content="O'Reilly & Associates, Inc." /><meta name="DC.Source" scheme="ISBN" content="0596002416L" /><meta name="DC.Subject.Keyword" content="stuff" /><meta name="DC.Title" content="Perl in a Nutshell, 2nd Edition" /><meta name="DC.Type" content="Text.Monograph" /></head><body bgcolor="#ffffff"><img src="gifs/smbanner.gif" usemap="#banner-map" border="0" alt="Book Home" /><map name="banner-map"><area shape="rect" coords="1,-2,616,66" href="index.htm" alt="Java and XSLT" /><area shape="rect" coords="629,-11,726,25" href="jobjects/fsearch.htm" alt="Search this book" /></map><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch21_15.htm"><img src="../gifs/txtpreva.gif" alt="Previous" border="0" /></a></td><td align="center" valign="top" width="228" /><td align="right" valign="top" width="228"><a href="ch21_17.htm"><img src="../gifs/txtnexta.gif" alt="Next" border="0" /></a></td></tr></table></div><h2 class="sect1">21.16. The Optionmenu Widget</h2><p><a name="INDEX-3111" /><a name="INDEX-3112" /><a name="INDEX-3113" />Use the <tt class="literal">Optionmenu</tt>method to create an option menu, in which the selected item is thevalue displayed. For example:</p><blockquote><pre class="code">$mainwindow->OptionMenu(-textvariable => \$platform, -options => [ [ "UNIX", "unix" ], [ "Windows NT", "winnt" ], [ "Macintosh", "mac" ] ]) -> pack;</pre></blockquote><p><a name="INDEX-3114" />The<tt class="literal">-options</tt> argument takes a list of menu items. Ifthe descriptions of the menu items displayed are different from thoseof the values stored, the menu items are themselves written astwo-item lists.</p><p>The standard configuration options that apply to<tt class="literal">Optionmenu</tt> are:<tt class="literal">-activeback</tt>-<tt class="literal">ground</tt>,<tt class="literal">-activeforeground</tt>, <tt class="literal">-background</tt>,<tt class="literal">-bg</tt>, <tt class="literal">-bitmap</tt>,<tt class="literal">-borderwidth</tt>, <tt class="literal">-bw</tt>,<tt class="literal">-cursor</tt>, <tt class="literal">-disabledforeground</tt>,<tt class="literal">-font</tt>, <tt class="literal">-foreground</tt>,<tt class="literal">-fg</tt>, <tt class="literal">-highlightbackground</tt>,<tt class="literal">-highlight</tt>-<tt class="literal">color</tt>,<tt class="literal">-highlightthickness</tt>, <tt class="literal">-image</tt>,<tt class="literal">-justify</tt>, <tt class="literal">-relief</tt>,<tt class="literal">-state</tt>, <tt class="literal">-takefocus</tt>,<tt class="literal">-un</tt>-<tt class="literal">derline</tt>,<tt class="literal">-width</tt>, and <tt class="literal">-wraplength</tt>.</p><p>Other options are:</p><dl><dt><b><tt class="literal">-command =></tt> <em class="replaceable">callback</em></b></dt><dd><a name="INDEX-3115" />The command to execute when a selectionis made. Its arguments are the values of the<tt class="literal">-textvariable</tt> and <tt class="literal">-variable</tt>options.</p></dd><dt><b><tt class="literal">-indicatoron =></tt> <em class="replaceable">boolean</em></b></dt><dd><a name="INDEX-3116" />Determines whether to display anindicator.</p></dd><dt><b><tt class="literal">-menu =></tt> <tt class="literal">$</tt><em class="replaceable">menu</em></b></dt><dd><a name="INDEX-3117" />Displays the menu associated with<tt class="literal">$</tt><em class="replaceable"><tt>menu</tt></em>.</p></dd><dt><b><tt class="literal">-options =></tt> <em class="replaceable">list</em></b></dt><dd>Lists the menu options, as described above.</p></dd><dt><b><tt class="literal">-tearoff =></tt> <em class="replaceable">boolean</em></b></dt><dd><a name="INDEX-3118" />Whether to allow the menu to be"torn off." Default is<tt class="literal">1</tt>.</p></dd><dt><b><tt class="literal">-text =></tt> <em class="replaceable">string</em></b></dt><dd><a name="INDEX-3119" />Specifies the text to display as alabel for the option menu.</p></dd><dt><b><tt class="literal">-textvariable =></tt> <tt class="literal">\$</tt><em class="replaceable">variable</em></b></dt><dd><a name="INDEX-3120" />Points to the variable containing textto be displayed in the option menu.</p></dd><dt><b><tt class="literal">-variable =></tt> <tt class="literal">\$</tt><em class="replaceable">variable</em></b></dt><dd><a name="INDEX-3121" />Points to a variable containing astored value, distinct from the value shown in the option menu.</p></dd></dl><hr width="684" align="left" /><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch21_15.htm"><img src="../gifs/txtpreva.gif" alt="Previous" border="0" /></a></td><td align="center" valign="top" width="228"><a href="index.htm"><img src="../gifs/txthome.gif" alt="Home" border="0" /></a></td><td align="right" valign="top" width="228"><a href="ch21_17.htm"><img src="../gifs/txtnexta.gif" alt="Next" border="0" /></a></td></tr><tr><td align="left" valign="top" width="228">21.15. The Menu Widget</td><td align="center" valign="top" width="228"><a href="index/index.htm"><img src="../gifs/index.gif" alt="Book Index" border="0" /></a></td><td align="right" valign="top" width="228">21.17. The Frame Widget</td></tr></table></div><hr width="684" align="left" /><img src="../gifs/navbar.gif" usemap="#library-map" border="0" alt="Library Navigation Links" /><p><p><font size="-1"><a href="copyrght.htm">Copyright © 2002</a> O'Reilly & Associates. 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