当按下JButton时，如何使JScrollPane设置在底部？

Question

I have a panel in which there is a JScrollPane and a JButton . I want to know how I can set the scroll pane's vertical scroll bar to bottom when I press the button.

I have tried code:-

private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {
    writeClient();
    jScrollPane2.getVerticalScrollBar().setValue(jScrollPane2.getVerticalScrollBar().getMaximum());
}         

But it doesn't lead to extreme bottom - a little space is still left at the bottom.

Answer 1

I am having problems to reproduce you issue. If you can post all the relevant code (and maybe include a screenshot), we can give you better advice. When I run the code below, pressing the button moves the scroll pane all the way down:

public class ScrollPaneBottom {
    public static void main(final String[] args) {
        new ScrollPaneBottom().test();
    }

    private void test() {
    final JFrame frame = new JFrame("Move a scroll pane to the bottom");
    frame.setBounds(100, 100, 800, 110);
    frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    final String[][] data = {{"One", "Hello"}, {"Une", "Bonjour"}, 
        {"Ein", "Hallo"}, {"Uno", "Hola"}, {"Een", "Hallo"}};
    final String[] columnNames = {"Number", "Word"};
    final JTable table = new JTable(new DefaultTableModel(data, columnNames));
    final JScrollPane scrollPane = new JScrollPane(table);
        final JButton button = new JButton("Move to the bottom");
        button.addActionListener(e -> {
            final int maximum = scrollPane.getVerticalScrollBar().getMaximum();
            scrollPane.getVerticalScrollBar().setValue(maximum);
        });
        frame.getContentPane().setLayout(new BorderLayout());
        frame.getContentPane().add(scrollPane, BorderLayout.CENTER);
        frame.getContentPane().add(button, BorderLayout.SOUTH);
        frame.setVisible(true);
    }
}