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The java::bind Command
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The java::bind Command
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Usage:
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<DD><B>java::bind </B><I>javaObj</I>
<DD><B>java::bind </B><I>javaObj eventName</I>
<DD><B>java::bind </B><I>javaObj eventName script</I>
<P>
The <B>java::bind</B> command is used to associate scripts with events
fired by Java objects. The <I>javaObj</I> argument specifies a Java
object. The <I>eventName</I> argument identifies an event fired by the
object.
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The events fired by Java objects are divided into <I>event
interfaces</I>. Each event is represented by an <I>event method</I> in
an event interface. For example, objects of the <B>java.awt.Button</B>
class can fire events in the <B>ActionListener</B>,
<B>ComponentListener</B>, <B>FocusListener</B>, <B>KeyListener</B>,
<B>MouseListener</B> and <B>MouseMotionListener</B> interfaces (all
these interfaces are defined in the JDK package <B>java.awt.event</B>.)
The <B>KeyListener</B> interface in turn contains the event methods
<B>keyPressed</B>, <B>keyReleased</B> and <B>keyTyped</B>. To find out
what events are fired by different Java classes, please consult their
API documentation.
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The <I>eventName</I> argument for the <B>java::bind</B> command is the
full or abbreviated name of the event. The full event name is the name
of an event interface, followed by the character "<B>.</B>", followed
by the name of the event method. For example,
<B>java.awt.event.KeyListener.keyTyped</B>. The abbreviated event name
is just the name of the event method. For example, <B>keyTyped</B>.
Abbreviated event names may be used only if the event method name
appears in exactly one of the event interfaces of the object.
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If the <I>script</I> argument is given, it specifies a <I>callback
script</I> to to be executed when the given event is fired in the
<I>javaObj</I>. If a callback script already exists for the given event
in <I>javaObj</I>, it will be replaced by <I>script</I>. If <I>script</I>
is the empty string, any previously installed callback
scripts for the given event in <I>javaObj</I> will be removed.
See the <A HREF="JavaEventScripts.html">Event Scripts</A> section for
more information.
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If the <I>script</I> argument is not given, the <B>java::bind</B>
command returns the current callback script, if any, for the given
event in <I>javaObj</I>.
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If the <I>eventName</I> and <I>script</I> arguments are both omitted,
the <B>java::bind</B> command returns a Tcl list of the full names
of all the events that are currently associated with
callback scripts for the given <I>javaObj</I>.
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Example:
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<DD>
This example creates a frame containing a single button widget. It then
uses the <B>java::bind</B> command to associate a Tcl script that will
be invoked when the <B>ActionListener.actionPerformed</B> interface method
is invoked. When the user presses the button, the Tcl script will be
evaluated inside the interpreter.
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<code>
<pre>
package require JBlend
java::import -package java.awt Frame Button
set f [java::new Frame]
set b [java::new Button "Hi"]
$f setSize 70 70
$f add $b
$f show
java::bind $b actionPerformed {
puts "Hi there"
}
</pre>
</code>
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<PRE>
<A HREF="../license.html">Copyright</A> © 1997-1998 Sun Microsystems, Inc.
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