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44 lines
2.5 KiB
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<TITLE> Variables<A NAME=6121> </A></TITLE>
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<HR> <A NAME=tex2html1134 HREF=subsubsectionstar3_8_1_4.html><IMG ALIGN=MIDDLE SRC="../gif/icons/next_motif.gif"></A> <A NAME=tex2html1132 HREF=subsection3_8_1.html><IMG ALIGN=MIDDLE SRC="../gif/icons/up_motif.gif"></A> <A NAME=tex2html1126 HREF=subsubsection3_8_1_2.html><IMG ALIGN=MIDDLE SRC="../gif/icons/previous_motif.gif"></A> <A NAME=tex2html1136 HREF=tableofcontents3_1.html><IMG ALIGN=MIDDLE SRC="../gif/icons/contents_motif.gif"></A> <BR>
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<B> Next:</B> <A NAME=tex2html1135 HREF=subsubsectionstar3_8_1_4.html> Methods</A>
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<B>Up:</B> <A NAME=tex2html1133 HREF=subsection3_8_1.html> Introduction to Tix </A>
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<B> Previous:</B> <A NAME=tex2html1127 HREF=subsubsection3_8_1_2.html> What is in </A>
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<A NAME=Contents> </A><H3><A NAME=SECTION00081300000000000000> Variables<A NAME=6121> </A></A></H3>
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<P>
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Each widget instance is associated with a set of variables. In the
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example of an instance of the TixArrowButton class, we may use a
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variable to store the direction to which the arrow is pointing
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to. We may also use a variable to count how many times the user has
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pressed the button.
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<P>
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Each variable can be public or private. Public variables may be
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accessed by the application programmer (usually via <tt>configure</tt>
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or cget <tt>methods</tt>) and their names usually start with a dash
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(<tt>-</tt>). They usually are used to represent some user-configurable
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options of the widget instance. Private variables, on the other
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hand, cannot be accessed by the application programmer. They are
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usually used to store information about the widget instance that are
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of interests only to the widget writer.
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<P>
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All the variables of an instance are stored in a global array that
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has the same name as the instance. For example, the variables of the
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instance <tt>.up</tt> are stored in the global array <tt>.up:</tt>. The
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public variable <tt>-direction</tt>, which records the direction to
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which the arrow is pointing to, is stored in <tt>.up(-direction)</tt>.
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The private variable <tt>count</tt>, which counts how many times the
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user has pressed the button, is stored in <tt>.up(count)</tt>. In
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comparison, the same variables of the <tt>.down</tt> instance are
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stored in <tt>.down(-direction)</tt> and <tt>.down(count)</tt>.
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<P><ADDRESS>
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<A HREF=http://tix.sourceforge.net>http://tix.sourceforge.net</A><BR>
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