-1
従業員のID番号に基づいてダイアログ内にコンボボックスを表示しようとしています。ユーザーがIDを選択すると、アプリケーションはこの従業員のデータを表示します。ダイアログ内のJComboBox
byIdItem.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
combo = new JComboBox(idNumbers);
String[] options = { "OK", "Cancel"};
int selection = JOptionPane.showOptionDialog(null, combo, "Search",
JOptionPane.DEFAULT_OPTION, JOptionPane.PLAIN_MESSAGE, null,
options, options[0]);
if (selection > 0) {
System.out.println("selection is: " + options[selection]);
}
currentItem = ((JComboBox)(e.getSource())).getSelectedIndex();
displayDetails(currentItem);}
});
この結果、私はちょうどnull pointer exceptionを持っています。 ありがとうございます！
スタックトレース：
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at javax.swing.DefaultComboBoxModel.<init>(DefaultComboBoxModel.java:53)
at javax.swing.JComboBox.<init>(JComboBox.java:175)
at SearchId.initComponents(SearchId.java:37)
at SearchId.<init>(SearchId.java:26)
at EmployeeMenu$6.actionPerformed(EmployeeMenu.java:255)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2028)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2351)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
at javax.swing.AbstractButton.doClick(AbstractButton.java:389)
at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:809)
at com.apple.laf.AquaMenuItemUI.doClick(AquaMenuItemUI.java:137)
at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:850)
at java.awt.Component.processMouseEvent(Component.java:6414)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3275)
at java.awt.Component.processEvent(Component.java:6179)
at java.awt.Container.processEvent(Container.java:2084)
at java.awt.Component.dispatchEventImpl(Component.java:4776)
at java.awt.Container.dispatchEventImpl(Container.java:2142)
at java.awt.Component.dispatchEvent(Component.java:4604)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4618)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4279)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4209)
at java.awt.Container.dispatchEventImpl(Container.java:2128)
at java.awt.Window.dispatchEventImpl(Window.java:2492)
at java.awt.Component.dispatchEvent(Component.java:4604)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:717)
at java.awt.EventQueue.access$400(EventQueue.java:82)
at java.awt.EventQueue$2.run(EventQueue.java:676)
at java.awt.EventQueue$2.run(EventQueue.java:674)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:86)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:690)
at java.awt.EventQueue$3.run(EventQueue.java:688)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:86)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:687)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:296)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:211)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:196)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:188)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
：ユーザーがあなたのコンボの選択項目が
を変更する項目を選択すると だから一緒に行きますか？ –
'idNumbers'とは何ですか？ –
idNumbersがnullの場合、同様のスタックトレースを取得します。また、currentItem =（（JComboBox）（e.getSource（）））。getSelectedIndex（）;コンボの選択された値のインデックスを含むことはありません。 e.getSource（）は別のオブジェクトです。 – RubioRic