/*******************************************************************************
* Copyright (c) 2006 Sybase, Inc. 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:
* Sybase, Inc. - initial API and implementation
*******************************************************************************/
package org.eclipse.jst.pagedesigner.css2.layout;
import org.eclipse.draw2d.FigureUtilities;
import org.eclipse.draw2d.Graphics;
import org.eclipse.draw2d.Label;
import org.eclipse.draw2d.geometry.Dimension;
import org.eclipse.draw2d.geometry.Rectangle;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.FontMetrics;
/**
* A multi-line label
*
*/
public class MultiLineLabel extends Label {
private static String ELLIPSIS = "..."; //$NON-NLS-1$
protected void paintFigure(Graphics graphics) {
if (isOpaque()) {
graphics.fillRectangle(getBounds());
}
Rectangle bounds1 = getBounds();
graphics.translate(bounds1.x, bounds1.y);
drawText(graphics);
graphics.translate(-bounds1.x, -bounds1.y);
}
private void drawText(Graphics graphics) {
String[] strings = splitString(getText());
int y = 0;
int lineHeight = FigureUtilities.getFontMetrics(getFont()).getHeight();
for (int i = 0; i < strings.length; i++) {
graphics.drawText(getSubStringText(strings[i]), 0, y);
y += lineHeight;
}
}
private String[] splitString(String text) {
String[] lines = new String[1];
int start = 0, pos;
do {
pos = text.indexOf('\n', start);
if (pos == -1) {
lines[lines.length - 1] = text.substring(start);
} else {
boolean crlf = (pos > 0) && (text.charAt(pos - 1) == '\r');
lines[lines.length - 1] = text.substring(start, pos
- (crlf ? 1 : 0));
start = pos + 1;
String[] newLines = new String[lines.length + 1];
System.arraycopy(lines, 0, newLines, 0, lines.length);
lines = newLines;
}
} while (pos != -1);
return lines;
}
/**
* @param text
* @return the substring text
*/
private String getSubStringText(String text) {
String subStringText = text;
Font currentFont = getFont();
int textWidth = FigureUtilities.getTextWidth(text, currentFont);
if (textWidth - getSize().width <= 0) {
return subStringText;
}
Dimension effectiveSize = new Dimension(getSize().width, 0);
int dotsWidth = FigureUtilities.getTextWidth(ELLIPSIS, currentFont);
if (effectiveSize.width < dotsWidth) {
effectiveSize.width = dotsWidth;
}
int subStringLength = getLargestSubstringConfinedTo(text, currentFont,
effectiveSize.width - dotsWidth);
subStringText = new String(text.substring(0, subStringLength)
+ ELLIPSIS);
return subStringText;
}
int getLargestSubstringConfinedTo(String s, Font f, int availableWidth) {
FontMetrics metrics = FigureUtilities.getFontMetrics(f);
int min, max;
float avg = metrics.getAverageCharWidth();
min = 0;
max = s.length() + 1;
// The size of the current guess
int guess = 0, guessSize = 0;
while ((max - min) > 1) {
// Pick a new guess size
// New guess is the last guess plus the missing width in pixels
// divided by the average character size in pixels
guess = guess + (int) ((availableWidth - guessSize) / avg);
if (guess >= max) {
guess = max - 1;
}
if (guess <= min) {
guess = min + 1;
}
// Measure the current guess
guessSize = FigureUtilities
.getTextExtents(s.substring(0, guess), f).width;
if (guessSize < availableWidth) {
// We did not use the available width
min = guess;
} else {
// We exceeded the available width
max = guess;
}
}
return min;
}
}