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POJComboBox Item Listener Selected Item
 

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    <p>I am creating a combo box and it keeps giving me an error with the item listener that I don't understand. If you could also explain your answer that would be nice. Thanks in advance: </p> <p>Here's the item listeners for the combo boxes:</p> <pre><code>combo1.addItemListener(new ItemListener(){ @Override public void itemStateChanged(ItemEvent e){ if(e.getStateChange() == ItemEvent.SELECTED){ JComboBox localCombo = (JComboBox)e.getSource(); ic1[0] = localCombo.getSelectedItem().toString(); } } }); combo2.addItemListener(new ItemListener(){ @Override public void itemStateChanged(ItemEvent e){ if(e.getStateChange() == ItemEvent.SELECTED){ JComboBox localCombo = (JComboBox)e.getSource(); ic1[1] = localCombo.getSelectedItem().toString(); } } }); </code></pre> <p>The error says it is on the .getSelectedItem()... lines. It only gives me the error when I run the program and select a word in the box. Thanks!</p> <p>Here's the error in the run (line 61 is the .getSelectedItem()... line):</p> <pre><code> run: Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at thisprogramisforfun.guiClasses.guiClassConversions$1.itemStateChanged(guiClassConversions.java:61) at javax.swing.JComboBox.fireItemStateChanged(JComboBox.java:1225) at javax.swing.JComboBox.selectedItemChanged(JComboBox.java:1282) at javax.swing.JComboBox.contentsChanged(JComboBox.java:1329) at javax.swing.AbstractListModel.fireContentsChanged(AbstractListModel.java:118) at javax.swing.DefaultComboBoxModel.setSelectedItem(DefaultComboBoxModel.java:93) at javax.swing.JComboBox.setSelectedItem(JComboBox.java:578) at javax.swing.JComboBox.setSelectedIndex(JComboBox.java:624) at javax.swing.plaf.basic.BasicComboPopup$Handler.mouseReleased(BasicComboPopup.java:835) at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:290) at java.awt.Component.processMouseEvent(Component.java:6505) at javax.swing.JComponent.processMouseEvent(JComponent.java:3320) at javax.swing.plaf.basic.BasicComboPopup$1.processMouseEvent(BasicComboPopup.java:499) at java.awt.Component.processEvent(Component.java:6270) at java.awt.Container.processEvent(Container.java:2229) at java.awt.Component.dispatchEventImpl(Component.java:4861) at java.awt.Container.dispatchEventImpl(Container.java:2287) at java.awt.Component.dispatchEvent(Component.java:4687) at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832) at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492) at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422) at java.awt.Container.dispatchEventImpl(Container.java:2273) at java.awt.Window.dispatchEventImpl(Window.java:2719) at java.awt.Component.dispatchEvent(Component.java:4687) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:735) at java.awt.EventQueue.access$200(EventQueue.java:103) at java.awt.EventQueue$3.run(EventQueue.java:694) at java.awt.EventQueue$3.run(EventQueue.java:692) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87) at java.awt.EventQueue$4.run(EventQueue.java:708) at java.awt.EventQueue$4.run(EventQueue.java:706) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.awt.EventQueue.dispatchEvent(EventQueue.java:705) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138) at java.awt.EventDispatchThread.run(EventDispatchThread.java:91) </code></pre>
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