/*******************************************************************************
* Copyright (c) 2012, 2015 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
******************************************************************************/
package org.eclipse.jface.util;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SegmentEvent;
import org.eclipse.swt.events.SegmentListener;
import org.eclipse.swt.widgets.Control;
/**
* Defines the segment listener that enforces Base Text Direction (BTD) support.
*
* @since 3.9
*/
/*package*/ class BaseTextDirectionSegmentListener implements SegmentListener {
private String textDirection;
/**
* Creates a new segment listener that enforces Base Text Direction (BTD) support.
*
* @param textDir the text direction
* Possible values are:
* <ul>
* <li> {@link BidiUtils#LEFT_TO_RIGHT}
* <li> {@link BidiUtils#RIGHT_TO_LEFT}
* <li> {@link BidiUtils#AUTO}
* </ul>
*/
public BaseTextDirectionSegmentListener(String textDir) {
super();
textDirection = textDir;
}
@Override
public void getSegments(SegmentEvent event) {
int length = event.lineText.length();
if (length > 0) {
boolean isRTL = isRTLValue(event.lineText);
if (event.widget instanceof Control && Util.isWindows()) {
if (isRTL) {
((Control) event.widget).setOrientation(SWT.RIGHT_TO_LEFT);
} else {
((Control) event.widget).setOrientation(SWT.LEFT_TO_RIGHT);
}
} else {
event.segments = new int[2];
event.segments[0] = 0;
event.segments[1] = length;
event.segmentsChars = new char[2];
event.segmentsChars[0] = isRTL ? BidiUtils.RLE : BidiUtils.LRE;
event.segmentsChars[1] = BidiUtils.PDF;
}
}
}
protected boolean isRTLValue(String stringValue) {
if (stringValue == null || stringValue.length() == 0 || BidiUtils.LEFT_TO_RIGHT.equals(textDirection))
return false;
if (BidiUtils.RIGHT_TO_LEFT.equals(textDirection))
return true;
for (int i = 0; i < stringValue.length(); i++) {
if (Character.getDirectionality(stringValue.charAt(i)) == Character.DIRECTIONALITY_RIGHT_TO_LEFT
|| Character.getDirectionality(stringValue.charAt(i)) == Character.DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC
|| Character.getDirectionality(stringValue.charAt(i)) == Character.DIRECTIONALITY_ARABIC_NUMBER)
return true;
else if (Character.getDirectionality(stringValue.charAt(i)) == Character.DIRECTIONALITY_LEFT_TO_RIGHT) {
return false;
}
}
return false;
}
}