/*******************************************************************************
* Copyright (c) 2000, 2010, 2012 IBM Corporation, Gerhardt Informatics Kft. 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
* Gerhardt Informatics Kft. - GEFGWT port
*******************************************************************************/
package org.eclipse.draw2d.widgets;
import org.eclipse.draw2d.Border;
import org.eclipse.draw2d.ColorConstants;
import org.eclipse.draw2d.FigureCanvas;
import org.eclipse.draw2d.FocusEvent;
import org.eclipse.draw2d.Graphics;
import org.eclipse.draw2d.MarginBorder;
import org.eclipse.draw2d.Viewport;
import org.eclipse.draw2d.geometry.Point;
import org.eclipse.draw2d.text.FlowPage;
import org.eclipse.draw2d.text.TextFlow;
import org.eclipse.swt.SWT;
import org.eclipse.swt.accessibility.ACC;
import org.eclipse.swt.accessibility.AccessibleAdapter;
import org.eclipse.swt.accessibility.AccessibleControlAdapter;
import org.eclipse.swt.accessibility.AccessibleControlEvent;
import org.eclipse.swt.accessibility.AccessibleEvent;
import org.eclipse.swt.events.KeyAdapter;
import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Composite;
/**
* A widget for displaying a multi-line string. The label will have a vertical
* or horizontal scrollbar when needed. Unlike the platform Label, this label is
* focusable and accessible to screen-readers.
*
* @author hudsonr
*/
public final class MultiLineLabel extends FigureCanvas {
private TextFlow textFlow;
static final Border MARGIN = new MarginBorder(2);
private Image image;
class FocusableViewport extends Viewport {
FocusableViewport() {
super(true);
setFocusTraversable(true);
setBorder(MARGIN);
}
public void handleFocusGained(FocusEvent event) {
super.handleFocusGained(event);
repaint();
}
public void handleFocusLost(FocusEvent event) {
super.handleFocusLost(event);
repaint();
}
protected void paintBorder(Graphics graphics) {
super.paintBorder(graphics);
if (hasFocus()) {
graphics.setForegroundColor(ColorConstants.black);
graphics.setBackgroundColor(ColorConstants.white);
graphics.drawFocus(getBounds().getResized(-1, -1));
}
}
}
/**
* Constructs a new MultiLineLabel with the given parent.
*
* @param parent
* the parent
*/
public MultiLineLabel(Composite parent) {
super(parent);
setViewport(new FocusableViewport());
FlowPage page = new FlowPage();
textFlow = new TextFlow();
page.add(textFlow);
setContents(page);
getViewport().setContentsTracksWidth(true);
addAccessibility();
}
private void addAccessibility() {
getAccessible().addAccessibleControlListener(
new AccessibleControlAdapter() {
public void getRole(AccessibleControlEvent e) {
e.detail = ACC.ROLE_LABEL;
}
public void getState(AccessibleControlEvent e) {
e.detail = ACC.STATE_READONLY;
}
});
getAccessible().addAccessibleListener(new AccessibleAdapter() {
public void getName(AccessibleEvent e) {
e.result = getText();
}
});
addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent e) {
Point p = getViewport().getViewLocation();
int dy = getFont().getFontData()[0].getHeight();
int dx = dy * 3 / 2;
boolean mirrored = (e.widget.getStyle() & SWT.MIRRORED) != 0;
if (e.keyCode == SWT.ARROW_DOWN) {
scrollToY(p.y + dy / 2);
scrollToY(p.y + dy);
scrollToY(p.y + dy * 3 / 2);
scrollToY(p.y + dy * 2);
} else if (e.keyCode == SWT.ARROW_UP) {
scrollToY(p.y - dy / 2);
scrollToY(p.y - dy);
scrollToY(p.y - dy * 3 / 2);
scrollToY(p.y - dy * 2);
} else if ((!mirrored && e.keyCode == SWT.ARROW_RIGHT)
|| (mirrored && e.keyCode == SWT.ARROW_LEFT)) {
scrollToX(p.x + dx);
scrollToX(p.x + dx * 2);
scrollToX(p.x + dx * 3);
} else if ((!mirrored && e.keyCode == SWT.ARROW_LEFT)
|| (mirrored && e.keyCode == SWT.ARROW_RIGHT)) {
scrollToX(p.x - dx);
scrollToX(p.x - dx * 2);
scrollToX(p.x - dx * 3);
}
}
});
}
/**
* @see org.eclipse.swt.widgets.Control#setEnabled(boolean)
*/
public void setEnabled(boolean enabled) {
super.setEnabled(enabled);
textFlow.setEnabled(getEnabled());
}
/**
* @return the Image for this label, or <code>null</code> if there is none
* @see #setImage(Image)
*/
public Image getImage() {
return image;
}
/**
* Returns the text in this label.
*
* @return the text
*/
public String getText() {
return textFlow.getText();
}
/**
* @see org.eclipse.swt.widgets.Canvas#setFont(org.eclipse.swt.graphics.Font)
*/
public void setFont(Font font) {
super.setFont(font);
textFlow.revalidate();
}
/**
* @param image
* The <code>Image</code> to be used for this label. It can be
* <code>null</code>.
*/
public void setImage(Image image) {
this.image = image;
if (image != null)
setBorder(new ImageBorder(image));
else
setBorder(null);
}
/**
* Sets the text for this label.
*
* @param text
* the new text
*/
public void setText(String text) {
textFlow.setText(text);
}
}