JComboBox更改下拉弹出窗口

Question

基本上是弹出用于JComboBox中显示其衍生的JTextField下面，如何从怒吼取向为JcomboBox的弹出改变方向并在顶/显示JcomboBox的弹出超过该

编辑：基本JComboBox的代码示例

import java.awt.Dimension;
import javax.swing.*;
import javax.swing.plaf.basic.BasicComboBoxRenderer;

public class HighRowCombo {

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                new HighRowCombo().makeUI();
            }
        });
    }

    public void makeUI() {
        Object[] data = {"One", "Two with text", "Three with long text, with long text,with long text "};
        JComboBox comboBox = new JComboBox(data);
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLocationRelativeTo(null);
        frame.add(comboBox);
        frame.pack();
        BasicComboBoxRenderer renderer = (BasicComboBoxRenderer) comboBox.getRenderer();
        Dimension size = renderer.getPreferredSize();
        size.height += 50;
        renderer.setPreferredSize(size);
        frame.setVisible(true);
    }
}

编辑第二。MacOX的代码

import java.awt.*;
import javax.swing.*;

public class TestHighRow {

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel("com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel");
                } catch (Exception e) {
                    e.printStackTrace();
                }
                new TestHighRow().makeUI();
            }
        });
    }

    public void makeUI() {
        Object[] data = {"One", "Two", "Three"};
        JComboBox comboBox = new JComboBox(data);
        comboBox.setPreferredSize(comboBox.getPreferredSize());
        comboBox.setRenderer(new HighRowRenderer(comboBox.getRenderer()));
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        frame.getContentPane().add(comboBox);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static class HighRowRenderer implements ListCellRenderer {

        private final ListCellRenderer delegate;
        private int height = -1;

        public HighRowRenderer(ListCellRenderer delegate) {
            this.delegate = delegate;
        }

        @Override
        public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
            Component component = delegate.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
            Dimension size = component.getPreferredSize();
            if (height == -1) {
                height = size.height + 50;
            }
            size.height = height;
            component.setPreferredSize(size);
            if (component instanceof JLabel) {
                ((JLabel) component).setHorizontalTextPosition(JLabel.CENTER);
            }
            return component;
        }
    }
}

Answer 1

尝试在“ 组合框弹出”中找到的setPopupAbove（）方法。