/*******************************************************************************
* Copyright (c) 2004, 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.ui.forms.widgets;
import org.eclipse.swt.SWT;
import org.eclipse.swt.accessibility.ACC;
import org.eclipse.swt.accessibility.Accessible;
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.graphics.Color;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.forms.FormColors;
import org.eclipse.ui.internal.forms.widgets.FormUtil;
/**
* Hyperlink is a concrete implementation of the abstract base class that draws
* text in the client area. Text can be wrapped and underlined. Hyperlink is
* typically added to the hyperlink group so that certain properties are managed
* for all the hyperlinks that belong to it.
* <p>
* Hyperlink can be extended.
* <p>
* <dl>
* <dt><b>Styles:</b></dt>
* <dd>SWT.WRAP</dd>
* </dl>
*
* @see org.eclipse.ui.forms.HyperlinkGroup
* @since 3.0
*/
public class Hyperlink extends AbstractHyperlink {
private String text;
private static final String ELLIPSIS = "..."; //$NON-NLS-1$
private boolean underlined;
// The tooltip is used for two purposes - the application can set
// a tooltip or the tooltip can be used to display the full text when the
// the text has been truncated due to the label being too short.
// The appToolTip stores the tooltip set by the application. Control.tooltiptext
// contains whatever tooltip is currently being displayed.
private String appToolTipText;
/**
* Creates a new hyperlink control in the provided parent.
*
* @param parent
* the control parent
* @param style
* the widget style
*/
public Hyperlink(Composite parent, int style) {
super(parent, style);
initAccessible();
}
protected void initAccessible() {
Accessible accessible = getAccessible();
accessible.addAccessibleListener(new AccessibleAdapter() {
@Override
public void getName(AccessibleEvent e) {
e.result = getText();
if (e.result == null)
getHelp(e);
}
@Override
public void getHelp(AccessibleEvent e) {
e.result = getToolTipText();
}
});
accessible.addAccessibleControlListener(new AccessibleControlAdapter() {
@Override
public void getChildAtPoint(AccessibleControlEvent e) {
Point pt = toControl(new Point(e.x, e.y));
e.childID = (getBounds().contains(pt)) ? ACC.CHILDID_SELF
: ACC.CHILDID_NONE;
}
@Override
public void getLocation(AccessibleControlEvent e) {
Rectangle location = getBounds();
Point pt = toDisplay(new Point(location.x, location.y));
e.x = pt.x;
e.y = pt.y;
e.width = location.width;
e.height = location.height;
}
@Override
public void getChildCount(AccessibleControlEvent e) {
e.detail = 0;
}
@Override
public void getRole(AccessibleControlEvent e) {
e.detail = ACC.ROLE_LINK;
}
@Override
public void getDefaultAction (AccessibleControlEvent e) {
e.result = SWT.getMessage ("SWT_Press"); //$NON-NLS-1$
}
@Override
public void getState(AccessibleControlEvent e) {
int state = ACC.STATE_NORMAL;
if (Hyperlink.this.getSelection())
state = ACC.STATE_SELECTED | ACC.STATE_FOCUSED;
e.detail = state;
}
});
}
/**
* Sets the underlined state. It is not necessary to call this method when
* in a hyperlink group.
*
* @param underlined
* if <samp>true </samp>, a line will be drawn below the text for
* each wrapped line.
*/
public void setUnderlined(boolean underlined) {
this.underlined = underlined;
redraw();
}
/**
* Returns the underline state of the hyperlink.
*
* @return <samp>true </samp> if text is underlined, <samp>false </samp>
* otherwise.
*/
public boolean isUnderlined() {
return underlined;
}
/**
* Overrides the parent by incorporating the margin.
*/
@Override
public Point computeSize(int wHint, int hHint, boolean changed) {
checkWidget();
int innerWidth = wHint;
if (innerWidth != SWT.DEFAULT) {
innerWidth -= marginWidth * 2;
if (innerWidth < 0)
innerWidth = 0;
}
int innerHeight = hHint;
if (innerHeight != SWT.DEFAULT) {
innerHeight -= marginHeight * 2;
if (innerHeight < 0)
innerHeight = 0;
}
Point textSize = computeTextSize(innerWidth, innerHeight);
int textWidth = textSize.x + 2 * marginWidth;
int textHeight = textSize.y + 2 * marginHeight;
if (wHint != SWT.DEFAULT) {
textWidth = wHint;
}
if (hHint != SWT.DEFAULT) {
textHeight = hHint;
}
Rectangle trim = computeTrim(0, 0, textWidth, textHeight);
return new Point(trim.width, trim.height);
}
/**
* Returns the current hyperlink text.
*
* @return hyperlink text
*/
@Override
public String getText() {
return text;
}
@Override
public String getToolTipText () {
checkWidget();
return appToolTipText;
}
@Override
public void setToolTipText (String string) {
super.setToolTipText (string);
appToolTipText = super.getToolTipText();
}
/**
* Sets the text of this hyperlink.
*
* @param text
* the hyperlink text
*/
public void setText(String text) {
if (text != null)
this.text = text;
else
this.text = ""; //$NON-NLS-1$
redraw();
}
/**
* Paints the hyperlink text.
*
* @param gc
* graphic context
*/
@Override
protected void paintHyperlink(GC gc) {
Rectangle carea = getClientArea();
Rectangle bounds = new Rectangle(marginWidth, marginHeight, carea.width
- marginWidth - marginWidth, carea.height - marginHeight
- marginHeight);
paintText(gc, bounds);
}
/**
* Paints the hyperlink text in provided bounding rectangle.
*
* @param gc
* graphic context
* @param bounds
* the bounding rectangle in which to paint the text
*/
protected void paintText(GC gc, Rectangle bounds) {
gc.setFont(getFont());
Color fg = isEnabled() ? getForeground() : new Color(gc.getDevice(),FormColors.blend(getBackground().getRGB(), getForeground().getRGB(), 70));
try {
gc.setForeground(fg);
if ((getStyle() & SWT.WRAP) != 0) {
FormUtil.paintWrapText(gc, text, bounds, underlined);
} else {
Point totalSize = computeTextSize(SWT.DEFAULT, SWT.DEFAULT);
boolean shortenText =false;
if (bounds.width<totalSize.x) {
// shorten
shortenText=true;
}
int textWidth = Math.min(bounds.width, totalSize.x);
int textHeight = totalSize.y;
String textToDraw = getText();
if (shortenText) {
textToDraw = shortenText(gc, getText(), bounds.width);
if (appToolTipText == null) {
super.setToolTipText(getText());
}
}
else {
super.setToolTipText(appToolTipText);
}
gc.drawText(textToDraw, bounds.x, bounds.y, true);
if (underlined) {
int descent = gc.getFontMetrics().getDescent();
int lineY = bounds.y + textHeight - descent + 1;
gc.drawLine(bounds.x, lineY, bounds.x + textWidth, lineY);
}
}
} finally {
if (!isEnabled() && fg != null)
fg.dispose();
}
}
protected String shortenText(GC gc, String t, int width) {
if (t == null) return null;
int w = gc.textExtent(ELLIPSIS).x;
if (width<=w) return t;
int l = t.length();
int max = l/2;
int min = 0;
int mid = (max+min)/2 - 1;
if (mid <= 0) return t;
while (min < mid && mid < max) {
String s1 = t.substring(0, mid);
String s2 = t.substring(l-mid, l);
int l1 = gc.textExtent(s1).x;
int l2 = gc.textExtent(s2).x;
if (l1+w+l2 > width) {
max = mid;
mid = (max+min)/2;
} else if (l1+w+l2 < width) {
min = mid;
mid = (max+min)/2;
} else {
min = max;
}
}
if (mid == 0) return t;
return t.substring(0, mid)+ELLIPSIS+t.substring(l-mid, l);
}
protected Point computeTextSize(int wHint, int hHint) {
Point extent;
GC gc = new GC(this);
gc.setFont(getFont());
if ((getStyle() & SWT.WRAP) != 0 && wHint != SWT.DEFAULT) {
extent = FormUtil.computeWrapSize(gc, getText(), wHint);
} else {
extent = gc.textExtent(getText());
if ((getStyle() & SWT.WRAP)==0 && wHint!=SWT.DEFAULT)
extent.x = wHint;
}
gc.dispose();
return extent;
}
}