有没有办法正确对齐JCombobox中的文本

Question

我想要一个右对齐的JComboBox.我怎样才能做到这一点？有人说"你可以设置一个渲染器到JComboBox,它可以是一个JLabel有JLabel #setHorizo​​ntalAlignment(JLabel.RIGHT)",但我不知道怎么办呢？

Answer 1

有人说"你可以设置一个渲染器到JComboBox,它可以是一个JLabel,有JLabel#setHorizo​​ntalAlignment(JLabel.RIGHT)"

是的,默认的renederer是JLabel,因此您无需创建自定义渲染器.你可以使用:

((JLabel)comboBox.getRenderer()).setHorizontalAlignment(JLabel.RIGHT);

Answer 2

好吧,你可以使用ListCellRenderer,如下所示:

import java.awt.Component;
import java.awt.ComponentOrientation;
import javax.swing.DefaultListCellRenderer;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.SwingUtilities;

public class ComboboxDemo extends JFrame{
    public ComboboxDemo(){
        JComboBox<String> comboBox = new JComboBox<String>();
        comboBox.setRenderer(new MyListCellRenderer());
        comboBox.addItem("Hi");
        comboBox.addItem("Hello");
        comboBox.addItem("How are you?");

        getContentPane().add(comboBox, "North");
        setSize(400, 300);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
    }

    private static class MyListCellRenderer extends DefaultListCellRenderer {
        @Override
        public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
            Component component = super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
            component.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
            return component;
        }
    }

    public static void main(String [] args){
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new ComboboxDemo().setVisible(true);
            }
        });
    }
}