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<TITLE>Listening for Changes to the Selected Item in a JComboBox Component (Java Developers Almanac Example)
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<h3>e765. Listening for Changes to the Selected Item in a JComboBox Component</h3>
Item events are generated whenever the selected item changes. These
events are generated even while the user is moving through items in
the displayed popup menu. If the combobox is editable, this event
does not indicate whether the new item is taken from the predefined
list or not. If this information is necessary, see
<a href="../javax.swing/combobox_CbActionEvt.html" class="eglink"><b>e766</b> Listening for Action Events from a JComboBox Component</a>.
<pre> // Create an editable combobox
String[] items = {<font color="#0066ff"><i>"item1", "item2"</i></font>};
JComboBox cb = new JComboBox(items);
cb.setEditable(true);
// Create and register listener
MyItemListener actionListener = new MyItemListener();
cb.addItemListener(actionListener);
class MyItemListener implements ItemListener {
// This method is called only if a new item has been selected.
public void itemStateChanged(ItemEvent evt) {
JComboBox cb = (JComboBox)evt.getSource();
// Get the affected item
Object item = evt.getItem();
if (evt.getStateChange() == ItemEvent.SELECTED) {
// Item was just selected
} else if (evt.getStateChange() == ItemEvent.DESELECTED) {
// Item is no longer selected
}
}
}
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<b>Related Examples</b></font></td>
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e756. <a class="eglink" href="combobox_CbRead.html?l=rel">
Creating a JComboBox Component
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e757. <a class="eglink" href="combobox_CbGetCur.html?l=rel">
Getting and Setting the Selected Item in a JComboBox Component
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e758. <a class="eglink" href="combobox_CbGetItems.html?l=rel">
Getting the Items in a JComboBox Component
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e759. <a class="eglink" href="combobox_CbAddItems.html?l=rel">
Adding and Removing an Item in a JComboBox Component
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e760. <a class="eglink" href="combobox_CbMultiKey.html?l=rel">
Selecting an Item in a JComboBox Component with Multiple Keystrokes
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e761. <a class="eglink" href="combobox_CbIsMenu.html?l=rel">
Determining If the Menu of a JComboBox Component Is Visible
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e762. <a class="eglink" href="combobox_CbKeyPopup.html?l=rel">
Displaying the Menu in a JComboBox Component Using a Keystroke
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e763. <a class="eglink" href="combobox_CbIsKeySel.html?l=rel">
Displaying the Menu in a JComboBox Component Using a Keystroke If the Selected Item Is Not Unique
</a>
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e764. <a class="eglink" href="combobox_CbScrollList.html?l=rel">
Setting the Number of Visible Items in the Menu of a JComboBox Component
</a>
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e766. <a class="eglink" href="combobox_CbActionEvt.html?l=rel">
Listening for Action Events from a JComboBox Component
</a>
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e767. <a class="eglink" href="combobox_CbMenuEvt.html?l=rel">
Determining When the Menu of a JComboBox Component Is Displayed
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See also:
<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#Actions">
Actions
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JButton">
JButton
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<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#JDesktop%20and%20JInternalFrame">
JDesktop and JInternalFrame
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JFrame,%20JWindow,%20JDialog">
JFrame, JWindow, JDialog
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JLabel">
JLabel
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JList">
JList
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JProgressBar">
JProgressBar
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JRadioButton">
JRadioButton
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JScrollPane">
JScrollPane
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JSlider">
JSlider
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JSpinner
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JSplitPane
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JTabbedPane">
JTabbedPane
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#JToolBar">
JToolBar
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#Keystrokes%20and%20Input%20Maps">
Keystrokes and Input Maps
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#Layout">
Layout
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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
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<a class="eglink" href="/egs/javax.swing/pkg.html?l=rel#UI%20Default%20Values">
UI Default Values
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