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<TITLE>Enabling an Action (Java Developers Almanac Example)
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<B><A HREF="../javax.swing/pkg.html#Actions">Actions</A></B><font color="#666666" class="xsmall-font">
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<h3>e857. Enabling an Action</h3>
Actions can be bound to many different kinds of
components. When an action is enabled or disabled,
components that are bound to that action may
automatically alter its display to match the enabled state
of the action.
This example creates three components: a button, a text component,
and a menu item - - all bound to the same action.
When the action is disabled, the button and menu item will appear
disabled and the text component will not be able to invoke the action.
<pre> JFrame frame = new JFrame();
// Button
JButton button = new JButton(action);
// Text Component
JTextField textfield = new JTextField();
textfield.getInputMap(JComponent.WHEN_FOCUSED).put(
KeyStroke.getKeyStroke(<font color="#0066ff"><i>"F2"</i></font>), action.getValue(Action.NAME));
textfield.getActionMap().put(action.getValue(Action.NAME), action);
// Menu Item
JMenuBar menuBar = new JMenuBar();
JMenu menu = new JMenu(<font color="#0066ff"><i>"Menu Label"</i></font>);
menu.add(new JMenuItem(action));
menuBar.add(menu);
frame.setJMenuBar(menuBar);
// The action
public Action action = new AbstractAction(<font color="#0066ff"><i>"Action Name"</i></font>) {
public void actionPerformed(ActionEvent evt) {
// Perform action
}
};
</pre>
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<b>Related Examples</b></font></td>
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e855. <a class="eglink" href="CreateAction.html?l=rel">
Creating an Action
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e856. <a class="eglink" href="ListActions.html?l=rel">
Listing the Actions in a Component
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See also:
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JButton">
JButton
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JCheckBox">
JCheckBox
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JComboBox">
JComboBox
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JDesktop%20and%20JInternalFrame">
JDesktop and JInternalFrame
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JFrame,%20JWindow,%20JDialog">
JFrame, JWindow, JDialog
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JLabel">
JLabel
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JList">
JList
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JProgressBar">
JProgressBar
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JRadioButton">
JRadioButton
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JScrollPane">
JScrollPane
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JSlider">
JSlider
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JSpinner">
JSpinner
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JSplitPane">
JSplitPane
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JTabbedPane">
JTabbedPane
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JToolBar">
JToolBar
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#Keystrokes%20and%20Input%20Maps">
Keystrokes and Input Maps
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#Layout">
Layout
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#Look%20and%20Feel">
Look and Feel
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#Menus">
Menus
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#Progress%20Monitor">
Progress Monitor
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#The%20Screen">
The Screen
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#Tool%20Tips">
Tool Tips
</a>
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#UI%20Default%20Values">
UI Default Values
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