如何从右到左设置JTextArea的方向(在JOptionPane内)

Question

我JScrollPane跟JTextArea里面,我试图从右侧设置的JTextArea的方向向左所以里面的文字就会从右边开始,滚动条会出现在左边

我尝试过以下但是它们并没有影响方向的方向:

txt.applyComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
txt.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
txt.setAlignmentX(JTextArea.RIGHT_ALIGNMENT);

编辑:

两个答案camickr和trashgod提供的工作正常但不在我的程序中我使用我的JTextArea作为对象消息并将其传递给OptionPane.

EDIT2:

我发现,setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);如果我将它应用于JOptionPane内容,则无效.是否有替代方案解决此问题？

与我的代码类似:

import java.awt.*;
import java.util.*;
import javax.swing.*;
public class TextArea extends JPanel
{
    private JTextArea txt = new JTextArea();
    public TextArea()
    {
        setLayout(new GridLayout());
        txt.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
        JScrollPane scroll = new JScrollPane(txt);
        scroll.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
        setPreferredSize(new Dimension(200,200));
        this.add(scroll);
    }
    private void display()
    {
        Object[] options = {this};
        JOptionPane pane = new JOptionPane();
        int option = pane.showOptionDialog(null, null, "Title", JOptionPane.DEFAULT_OPTION, JOptionPane.PLAIN_MESSAGE, null, options, options[0]);
    }
    public static void main(String[] args)
    {
        new TextArea().display();
    }
}

Answer 1

滚动条将在左侧

scrollPane.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);

所以里面的文字将从右边开始

textArea.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);

文本从右侧开始,但在您键入时仍然会附加到末尾,而不是在行的开头插入.

更新:

我不知道为什么它在选项窗格中不起作用.这是一个简单的解决方案:

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

public class Test
{
    public static void main(String args[]) throws Exception
    {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                JTextArea textArea = new JTextArea(4, 20);
                JScrollPane scrollPane = new JScrollPane( textArea );
                JPanel panel = new JPanel();
                panel.add( scrollPane );

                scrollPane.addAncestorListener( new AncestorListener()
                {
                    public void ancestorAdded(AncestorEvent e)
                    {
                        JScrollPane scrollPane = (JScrollPane)e.getComponent();
                        scrollPane.applyComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
                    }

                    public void ancestorMoved(AncestorEvent e) {}
                    public void ancestorRemoved(AncestorEvent e) {}
                });

                JOptionPane.showMessageDialog(null, panel);
            }
        });
    }
}

Answer 2

这似乎有效.

import java.awt.ComponentOrientation;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.util.Locale;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;

/** @see http://stackoverflow.com/questions/6475320 */
public class RTLTextArea extends JPanel {

    private static final String s = "????? ??????";
    private JTextArea jta = new JTextArea(7, 5);
    private Locale arabic = new Locale("ar", "KW");
    private ComponentOrientation arabicOrientation =
        ComponentOrientation.getOrientation(arabic);

    public RTLTextArea() {
        this.setLayout(new GridLayout());
        this.add(new JScrollPane(jta));
        this.applyComponentOrientation(arabicOrientation);
        for (int i = 0; i < 8; i++) {
            jta.append(s + "\n");
        }
    }

    private void display() {
        JFrame f = new JFrame("RTLTextAre");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(this);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

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

            @Override
            public void run() {
                new RTLTextArea().display();
            }
        });
    }
}