PathTab.java

/*******************************************************************************
 * Copyright (c) 2006 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.swt.examples.graphics;

import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Device;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Path;
import org.eclipse.swt.graphics.Pattern;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.graphics.Transform;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Menu;

/**
 * This tab demonstrates the use of paths. It allows the user to see the differences between filling, drawing and
 * closing paths.
 */
public class PathTab extends GraphicsTab {

	Button				colorButton, fillButton, drawButton, closeButton;
	GraphicsBackground	fillColor;
	Menu				menu;

	public PathTab(GraphicsExample example) {
		super(example);
	}

	public void createControlPanel(Composite parent) {

		Composite comp;

		// create draw button
		comp = new Composite(parent, SWT.NONE);
		comp.setLayout(new GridLayout());

		drawButton = new Button(comp, SWT.TOGGLE);
		drawButton.setText(GraphicsExample.getResourceString("DrawPath")); //$NON-NLS-1$
		drawButton.addListener(SWT.Selection, new Listener() {
			public void handleEvent(Event event) {
				example.redraw();
			}
		});
		drawButton.setSelection(true);

		// create fill button
		comp = new Composite(parent, SWT.NONE);
		comp.setLayout(new GridLayout());

		fillButton = new Button(comp, SWT.TOGGLE);
		fillButton.setText(GraphicsExample.getResourceString("FillPath")); //$NON-NLS-1$
		fillButton.addListener(SWT.Selection, new Listener() {
			public void handleEvent(Event event) {
				example.redraw();
			}
		});

		// create close button
		comp = new Composite(parent, SWT.NONE);
		comp.setLayout(new GridLayout());

		closeButton = new Button(comp, SWT.TOGGLE);
		closeButton.setText(GraphicsExample.getResourceString("ClosePath")); //$NON-NLS-1$
		closeButton.addListener(SWT.Selection, new Listener() {
			public void handleEvent(Event event) {
				example.redraw();
			}
		});

		// create color button
		comp = new Composite(parent, SWT.NONE);
		comp.setLayout(new GridLayout());

		ColorMenu cm = new ColorMenu();
		cm.setPatternItems(example.checkAdvancedGraphics());
		menu = cm.createMenu(parent.getParent(), new ColorListener() {
			public void setColor(GraphicsBackground gb) {
				fillColor = gb;
				colorButton.setImage(gb.getThumbNail());
				example.redraw();
			}
		});

		// initialize the foreground to the 5th item in the menu (green)
		fillColor = (GraphicsBackground) menu.getItem(3).getData();

		// color button
		colorButton = new Button(comp, SWT.PUSH);
		colorButton.setText(GraphicsExample.getResourceString("FillColor")); //$NON-NLS-1$
		colorButton.setImage(fillColor.getThumbNail());
		colorButton.addListener(SWT.Selection, new Listener() {
			public void handleEvent(Event event) {
				final Button button = (Button) event.widget;
				final Composite parent = button.getParent();
				Rectangle bounds = button.getBounds();
				Point point = parent.toDisplay(new Point(bounds.x, bounds.y));
				menu.setLocation(point.x, point.y + bounds.height);
				menu.setVisible(true);
			}
		});
	}

	public void dispose() {
		if (menu != null) {
			menu.dispose();
			menu = null;
		}
	}

	public String getCategory() {
		return GraphicsExample.getResourceString("Path"); //$NON-NLS-1$
	}

	public String getDescription() {
		return GraphicsExample.getResourceString("PathOperDescription"); //$NON-NLS-1$
	}

	public String getText() {
		return GraphicsExample.getResourceString("PathOper"); //$NON-NLS-1$
	}

	public void paint(GC gc, int width, int height) {
		if (!example.checkAdvancedGraphics())
			return;
		Device device = gc.getDevice();

		Pattern pattern = null;
		if (fillColor.getBgColor1() != null)
			gc.setBackground(fillColor.getBgColor1());
		else if (fillColor.getBgImage() != null) {
			pattern = new Pattern(device, fillColor.getBgImage());
			gc.setBackgroundPattern(pattern);
		}

		gc.setLineWidth(5);
		gc.setForeground(device.getSystemColor(SWT.COLOR_BLACK));

		// arc
		Path path = new Path(device);
		path.addArc((width - 250) / 2, (height - 400) / 2, 500, 400, 90, 180);
		if (closeButton.getSelection())
			path.close();
		if (fillButton.getSelection())
			gc.fillPath(path);
		if (drawButton.getSelection())
			gc.drawPath(path);
		path.dispose();

		// shape on left
		Transform transform = new Transform(device);
		transform.translate((width - 250) / 4, height / 2 - 150);
		gc.setTransform(transform);
		transform.dispose();
		path = new Path(device);
		path.cubicTo(-150, 100, 150, 200, 0, 300);
		if (closeButton.getSelection())
			path.close();
		if (fillButton.getSelection())
			gc.fillPath(path);
		if (drawButton.getSelection())
			gc.drawPath(path);
		path.dispose();
		gc.setTransform(null);

		// shape on right
		path = new Path(device);
		path.moveTo(3 * (width - 250) / 4 - 25 + 250, height / 2);
		path.lineTo(3 * (width - 250) / 4 + 50 + 250, height / 2 - 200);
		path.lineTo(3 * (width - 250) / 4 + 50 + 250, height / 2 + 50);
		path.lineTo(3 * (width - 250) / 4 - 25 + 250, height / 2 + 150);
		path.lineTo(3 * (width - 250) / 4 + 25 + 250, height / 2 + 50);
		if (closeButton.getSelection())
			path.close();
		if (fillButton.getSelection())
			gc.fillPath(path);
		if (drawButton.getSelection())
			gc.drawPath(path);
		path.dispose();

		if (pattern != null)
			pattern.dispose();
	}
}