/*******************************************************************************
* Copyright (c) 2000, 2008 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.texteditor;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.DisposeEvent;
import org.eclipse.swt.events.DisposeListener;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.PaletteData;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.jface.text.source.Annotation;
import org.eclipse.jface.text.source.IAnnotationPresentation;
/**
* Specialized annotation to indicate a particular range of text lines.
* <p>
* This class may be instantiated; it is not intended to be subclassed.
* This class is instantiated automatically by <code>AbstractTextEditor</code>.
* </p>
* @noextend This class is not intended to be subclassed by clients.
*/
public class DefaultRangeIndicator extends Annotation implements IAnnotationPresentation {
/** The color palette data of this range indicator */
private static PaletteData fgPaletteData;
/** The image of this range indicator */
private Image fImage;
/**
* Creates a new range indicator.
*/
public DefaultRangeIndicator() {
}
/*
* @see org.eclipse.jface.text.source.IAnnotationPresentation#paint(org.eclipse.swt.graphics.GC, org.eclipse.swt.widgets.Canvas, org.eclipse.swt.graphics.Rectangle)
*/
public void paint(GC gc, Canvas canvas, Rectangle bounds) {
Point canvasSize= canvas.getSize();
int x= 0;
int y= bounds.y;
int w= canvasSize.x;
int h= bounds.height;
int b= 1;
if (y + h > canvasSize.y)
h= canvasSize.y - y;
if (y < 0) {
h= h + y;
y= 0;
}
if (h <= 0)
return;
Image image = getImage(canvas);
gc.drawImage(image, 0, 0, w, h, x, y, w, h);
gc.setBackground(canvas.getDisplay().getSystemColor(SWT.COLOR_LIST_SELECTION));
gc.fillRectangle(x, bounds.y, w, b);
gc.fillRectangle(x, bounds.y + bounds.height - b, w, b);
}
/*
* @see org.eclipse.jface.text.source.IAnnotationPresentation#getLayer()
*/
public int getLayer() {
return IAnnotationPresentation.DEFAULT_LAYER;
}
/**
* Returns the image of this range indicator.
*
* @param control the control
* @return an image
*/
private Image getImage(Control control) {
if (fImage == null) {
fImage= createImage(control.getDisplay(), control.getSize());
control.addDisposeListener(new DisposeListener() {
public void widgetDisposed(DisposeEvent e) {
if (fImage != null && !fImage.isDisposed()) {
fImage.dispose();
fImage= null;
}
}
});
} else {
Rectangle imageRectangle= fImage.getBounds();
Point controlSize= control.getSize();
if (imageRectangle.width < controlSize.x || imageRectangle.height < controlSize.y) {
fImage.dispose();
fImage= createImage(control.getDisplay(), controlSize);
}
}
return fImage;
}
/**
* Creates and returns a new SWT image with the given size on
* the given display which is used as this range indicator's image.
*
* @param display the display on which to create the image
* @param size the image size
* @return a new image
*/
private static Image createImage(Display display, Point size) {
int width= size.x;
int height= size.y;
if (fgPaletteData == null)
fgPaletteData= createPalette(display);
ImageData imageData= new ImageData(width, height, 1, fgPaletteData);
for (int y= 0; y < height; y++)
for (int x= 0; x < width; x++)
imageData.setPixel(x, y, (x + y) % 2);
return new Image(display, imageData);
}
/**
* Creates and returns a new color palette data.
*
* @param display the display
* @return the new color palette data
*/
private static PaletteData createPalette(Display display) {
Color c1;
Color c2;
c1= display.getSystemColor(SWT.COLOR_LIST_SELECTION);
c2= display.getSystemColor(SWT.COLOR_WIDGET_BACKGROUND);
RGB rgbs[]= new RGB[] {
new RGB(c1.getRed(), c1.getGreen(), c1.getBlue()),
new RGB(c2.getRed(), c2.getGreen(), c2.getBlue())};
return new PaletteData(rgbs);
}
}