Name: js5519 Date: 02/09/99


TextLayout always uses the default base direction as specified
by the Unicode algorithm (the direction of the first character
that has a strong direction in the string). Setting the direction
explicitly by calling
AttributedString.addAttribute(TextAttribute.RUN_DIRECTION, TextAttribute.RUN_DIRECTION_RTL /*or RUN_DIRECTION_LTR*/)
has no effect. The default direction will always be used.
I tested this on Windows NT 4.0 Arabic Edition.
In the following test case you'll notice that setting the
direction to LTR or RTL has no effect

Listing of BIDITest.java:
=========================

import java.awt.*;
import java.awt.font.*;
import java.awt.event.*;
import java.applet.*;
import java.text.*;

public class BIDITest extends Applet
{

  private CheckboxGroup cbg;
  private Checkbox cbRTL;
  private Checkbox cbLTR;
  private String s = "Hello, Hello, \u0623\u0647\u0644\u0627 \u0648\u0633\u0647\u0644\u0627";
  private boolean isRTL;

  public BIDITest()
  {
    init();
  }

  public static void main(String[] args)
  {
    BIDITest bidiTest = new BIDITest();
    Frame f = new Frame("BIDI Test");
    f.add(bidiTest);
    f.setSize(600, 400);
    f.addWindowListener( new WindowAdapter()
                              {
                                public void windowClosing(WindowEvent e)
                                {
                                  System.exit(0);
                                }
                              }
                        );
    f.show();
  }

  public void init()
  {
    setLayout(new BorderLayout());
    cbg = new CheckboxGroup();
    cbRTL = new Checkbox("Right to Left", false, cbg);
    cbLTR = new Checkbox("Left to Right", true, cbg);
    cbRTL.addItemListener( new ItemListener()
                              {
                                public void itemStateChanged(ItemEvent e)
                                {
                                  if(cbRTL.getState() == true)
                                    isRTL = true;

                                  repaint();
                                }
                              }
                         );
    cbLTR.addItemListener(new ItemListener()
                              {
                                public void itemStateChanged(ItemEvent e)
                                {
                                  if(cbLTR.getState() == true)
                                    isRTL = false;

                                  repaint();
                                }
                              }
                           );
    Panel p = new Panel();
    p.setLayout(new FlowLayout(FlowLayout.CENTER));
    p.add(cbLTR);
    p.add(cbRTL);
    p.setBackground(Color.gray);
    add(p, BorderLayout.SOUTH);
  }

  public void paint(Graphics g)
  {
    AttributedString as = new AttributedString(s);
    Boolean runDirection = isRTL ? TextAttribute.RUN_DIRECTION_RTL :
                                   TextAttribute.RUN_DIRECTION_LTR;
    as.addAttribute(TextAttribute.RUN_DIRECTION, runDirection);
    as.addAttribute(TextAttribute.FONT, new Font("Lucida Sans Regular", Font.PLAIN, 20));
    TextLayout tl = new TextLayout(as.getIterator(), ((Graphics2D)g).getFontRenderContext());
    tl.draw((Graphics2D)g, 100, 100);
    g.drawString("isRTL="+isRTL, 100, 150);
  }
}
(Review ID: 53958)
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