java - JTabbedPane ArrayIndexOutOfBoundsException : 0

Question

我试图在我的 Java Swing 应用程序中创建一个选项卡式 Pane ，但它不起作用。

将 JTabbedPane 设置为 contentpane 时，一切正常。一旦我尝试添加一个选项卡，我就会收到一个 ArrayIndexOutOfBoundsException: 0。

尽管如此，组件还是被添加到了 Pane 中，只是抛出了这个错误。我的代码和错误在下面。

代码:

// This all happens in a class which extends JFrame

private JTabbedPane contentPane;

/**
 * Launch the application.
 */
public static void main(String[] args) {
    SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            try {
                ConfigBuilderWindow frame = new ConfigBuilderWindow();
                frame.setVisible(true);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    });
}

/**
 * Create the frame.
 */
public ConfigBuilderWindow() {
    setTitle("Config Builder");
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setBounds(100, 100, 916, 617);
    contentPane = new JTabbedPane();
    contentPane.setBorder(new LineBorder(Color.BLUE, 4));
    contentPane.setLayout(new BorderLayout(0, 0));

    contentPane.addTab("Test1", new JButton("Test1"));
    contentPane.addTab("Test2", new JButton("Test2"));

    setContentPane(contentPane);
}

错误:

Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: 0
at javax.swing.plaf.basic.BasicTabbedPaneUI.paintTabArea(Unknown Source)
at javax.swing.plaf.basic.BasicTabbedPaneUI.paint(Unknown Source)
at javax.swing.plaf.metal.MetalTabbedPaneUI.paint(Unknown Source)
at javax.swing.plaf.metal.MetalTabbedPaneUI.update(Unknown Source)
at javax.swing.JComponent.paintComponent(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JLayeredPane.paint(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.paintToOffscreen(Unknown Source)
at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(Unknown Source)
at javax.swing.RepaintManager$PaintManager.paint(Unknown Source)
at javax.swing.RepaintManager.paint(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at java.awt.GraphicsCallback$PaintCallback.run(Unknown Source)
at sun.awt.SunGraphicsCallback.runOneComponent(Unknown Source)
at sun.awt.SunGraphicsCallback.runComponents(Unknown Source)
at java.awt.Container.paint(Unknown Source)
at java.awt.Window.paint(Unknown Source)
at javax.swing.RepaintManager$4.run(Unknown Source)
at javax.swing.RepaintManager$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at javax.swing.RepaintManager.paintDirtyRegions(Unknown Source)
at javax.swing.RepaintManager.paintDirtyRegions(Unknown Source)
at javax.swing.RepaintManager.prePaintDirtyRegions(Unknown Source)
at javax.swing.RepaintManager.access$1200(Unknown Source)
at javax.swing.RepaintManager$ProcessingRunnable.run(Unknown Source)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$500(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)

我希望任何人都知道发生了什么。

Answer 1

我不确定为什么要为 contentPane 设置 BorderLayout，我建议您将变量名称更改为 tabbedPane并删除这一行:

tabbedPane.setLayout(new BorderLayout(0, 0));

这修复了错误。

如果您想编辑选项卡的布局，请使用该布局创建一个 JPanel 并将其作为参数而不是您的 JButton 传递。

要注意的另一件事不是调用 setBounds 而是调用 pack() 和 setLocation() 或 setLocationRelativeTo 或setLocationByPlatform() 方法代替

现在，作为旁注，不要扩展 JFrame，参见 The use of multiple JFrames, Good / Bad practice? (普遍认为这是一种不好的做法)。另见 Extends JFrame vs creating it inside of class