examples/org.eclipse.swt.examples/src/org/eclipse/swt/examples/graphics/GraphicsExample.java - platform/eclipse.platform.swt - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2005 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 java.io.IOException;
 import java.io.InputStream;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.MissingResourceException;
 import java.util.ResourceBundle;
 import java.util.Vector;

 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
 import org.eclipse.swt.layout.*;
 import org.eclipse.swt.widgets.*;

 public class GraphicsExample {

 	Composite parent;
 	GraphicsTab[] tabs;
 	GraphicsTab tab;
 	Object[] tabBackground;

 	boolean animate;

 	Listener redrawListener;

 	ToolBar toolBar;
 	Tree tabList;
 	Canvas canvas;
 	Composite controlPanel, tabPanel;
 	ToolItem playItem, pauseItem, backItem, dbItem;
 	Spinner timerSpinner;

 	Menu backMenu;
 	MenuItem customMI;
 	Image customImage;
 	Color customColor;

 	Vector images;

 	static boolean advanceGraphics, advanceGraphicsInit;

 	static final int TIMER = 30;
 	static final ResourceBundle RESOURCE_BUNDLE = ResourceBundle.getBundle("examples_graphics"); //$NON-NLS-1$

 public GraphicsExample(final Composite parent) {
 	this.parent = parent;
 	redrawListener = new Listener() {
 		public void handleEvent(Event e) {
 			redraw();
 		}
 	};
 	GridData data;
 	GridLayout layout = new GridLayout(3, false);
 	layout.horizontalSpacing = 1;
 	parent.setLayout(layout);
 	tabs = createTabs();
 	images = new Vector();
 	createToolBar(parent);
 	createTabList(parent);
 	final Sash sash = new Sash(parent, SWT.VERTICAL);
 	createTabPanel(parent);
 	data = new GridData(SWT.FILL, SWT.CENTER, true, false);
 	data.horizontalSpan = 3;
 	toolBar.setLayoutData(data);
 	data = new GridData(SWT.CENTER, SWT.FILL, false, true);
 	data.widthHint = tabList.computeSize(SWT.DEFAULT, SWT.DEFAULT).x + 50;
 	tabList.setLayoutData(data);
 	data = new GridData(SWT.CENTER, SWT.FILL, false, true);
 	sash.setLayoutData(data);
 	data = new GridData(SWT.FILL, SWT.FILL, true, true);
 	tabPanel.setLayoutData(data);
 	sash.addListener(SWT.Selection, new Listener() {
 		public void handleEvent(Event event) {
 			if (event.detail != SWT.DRAG) {
 				GridData data = (GridData)tabList.getLayoutData();
 				data.widthHint = event.x - tabList.computeTrim(0, 0, 0, 0).width;
 				parent.layout(true);
 				animate = pauseItem.getEnabled();
 			} else {
 				animate = false;
 			}
 		}
 	});
 	setTab(tab);
 	startAnimationTimer();
 }

 boolean checkAdvancedGraphics() {
 	if (advanceGraphicsInit) return advanceGraphics;
 	advanceGraphicsInit = true;
 	Display display = Display.getCurrent();
 	try {
 		Path path = new Path(display);
 		path.dispose();
 	} catch (SWTException e) {
 		Shell shell = display.getActiveShell(), newShell = null;
 		if (shell == null) shell = newShell = new Shell(display);
 		MessageBox dialog = new MessageBox(shell, SWT.ICON_WARNING | SWT.OK);
 		dialog.setText(RESOURCE_BUNDLE.getString("Warning")); //$NON-NLS-1$
 		dialog.setMessage(RESOURCE_BUNDLE.getString("LibNotFound")); //$NON-NLS-1$
 		dialog.open();
 		if (newShell != null) newShell.dispose();
 		return false;
 	}
 	return advanceGraphics = true;
 }

 void createCanvas(Composite parent) {
 	canvas = new Canvas(parent, SWT.NO_BACKGROUND);
 	canvas.addListener(SWT.Paint, new Listener() {
 		public void handleEvent(Event event) {
 			GC gc;
 			Rectangle rect = canvas.getClientArea();
 			Image buffer = null;
 			if (dbItem.getSelection()) {
 				buffer = new Image(canvas.getDisplay(), rect);
 				gc = new GC(buffer);
 			} else {
 				gc = event.gc;
 			}
 			paintBackground(gc, rect);
 			GraphicsTab tab = getTab();
 			if (tab != null) tab.paint(gc, rect.width, rect.height);
 			if (gc != event.gc) gc.dispose();
 			if (buffer != null) {
 				event.gc.drawImage(buffer, 0, 0);
 				buffer.dispose();
 			}
 		}
 	});
 }

 void createControlPanel(Composite parent) {
 	Group group;
 	controlPanel = group = new Group(parent, SWT.NONE);
 	group.setText(getResourceString("Settings")); //$NON-NLS-1$
 	controlPanel.setLayout(new RowLayout());
 }

 void createTabPanel(Composite parent) {
 	tabPanel = new Composite(parent, SWT.NONE);
 	GridData data;
 	GridLayout layout = new GridLayout(1, false);
 	layout.marginHeight = layout.marginWidth = 0;
 	tabPanel.setLayout(layout);
 	createCanvas(tabPanel);
 	createControlPanel(tabPanel);
 	data = new GridData(SWT.FILL, SWT.FILL, true, true);
 	canvas.setLayoutData(data);
 	data = new GridData(SWT.FILL, SWT.CENTER, true, false);
 	controlPanel.setLayoutData(data);
 }

 void createToolBar(final Composite parent) {
 	final Display display = parent.getDisplay();

 	toolBar = new ToolBar(parent, SWT.FLAT);
 	Listener toolBarListener = new Listener() {
 		public void handleEvent(Event event) {
 			switch (event.type) {
 				case SWT.Selection: {
 					if (event.widget == playItem) {
 						animate = true;
 						playItem.setEnabled(!animate);
 						pauseItem.setEnabled(animate);
 					} else if (event.widget == pauseItem) {
 						animate = false;
 						playItem.setEnabled(!animate);
 						pauseItem.setEnabled(animate);
 					} else if (event.widget == backItem) {
 						final ToolItem toolItem = (ToolItem) event.widget;
 						final ToolBar  toolBar = toolItem.getParent();
 						Rectangle toolItemBounds = toolItem.getBounds();
 						Point point = toolBar.toDisplay(new Point(toolItemBounds.x, toolItemBounds.y));
 						backMenu.setLocation(point.x, point.y + toolItemBounds.height);
 						backMenu.setVisible(true);
 					}
 				}
 				break;
 			}
 		}
 	};

 	playItem = new ToolItem(toolBar, SWT.PUSH);
 	playItem.setText(getResourceString("Play")); //$NON-NLS-1$
 	playItem.setImage(loadImage(display, "play.gif")); //$NON-NLS-1$
 	playItem.addListener(SWT.Selection, toolBarListener);

 	pauseItem = new ToolItem(toolBar, SWT.PUSH);
 	pauseItem.setText(getResourceString("Pause")); //$NON-NLS-1$
 	pauseItem.setImage(loadImage(display, "pause.gif")); //$NON-NLS-1$
 	pauseItem.addListener(SWT.Selection, toolBarListener);

 	backItem = new ToolItem(toolBar, SWT.PUSH);
 	backItem.setText(getResourceString("Background")); //$NON-NLS-1$
 	backItem.addListener(SWT.Selection, toolBarListener);
 	String[] names = new String[]{
 		getResourceString("White"), //$NON-NLS-1$
 		getResourceString("Black"), //$NON-NLS-1$
 		getResourceString("Red"), //$NON-NLS-1$
 		getResourceString("Green"), //$NON-NLS-1$
 		getResourceString("Blue"), //$NON-NLS-1$
 		getResourceString("CustomColor"), //$NON-NLS-1$
 	};
 	Color[] colors = new Color[]{
 		display.getSystemColor(SWT.COLOR_WHITE),
 		display.getSystemColor(SWT.COLOR_BLACK),
 		display.getSystemColor(SWT.COLOR_RED),
 		display.getSystemColor(SWT.COLOR_GREEN),
 		display.getSystemColor(SWT.COLOR_BLUE),
 		null,
 	};
 	backMenu = new Menu(parent);
 	Listener listener = new Listener() {
 		public void handleEvent(Event event) {
 			MenuItem item = (MenuItem)event.widget;
 			if (customMI == item) {
 				ColorDialog dialog = new ColorDialog(parent.getShell());
 				RGB rgb = dialog.open();
 				if (rgb == null) return;
 				if (customColor != null) customColor.dispose();
 				customColor = new Color(display, rgb);
 				if (customImage != null) customImage.dispose();
 				customImage = createImage(display, customColor);
 				item.setData(new Object[]{customColor, customImage});
 				item.setImage(customImage);
 			}
 			tabBackground = (Object[])item.getData();
 			backItem.setImage((Image)tabBackground[1]);
 			canvas.redraw();
 		}
 	};
 	for (int i = 0; i < names.length; i++) {
 		MenuItem item = new MenuItem(backMenu, SWT.NONE);
 		item.setText(names[i]);
 		item.addListener(SWT.Selection, listener);
 		Image image = null;
 		if (colors[i] != null) {
 			image = createImage(display, colors[i]);
 			images.addElement(image);
 			item.setImage(image);
 		} else {
 			// custom menu item
 			customMI = item;
 		}
 		item.setData(new Object[]{colors[i], image});
 		if (tabBackground == null) {
 			tabBackground = (Object[])item.getData();
 			backItem.setImage((Image)tabBackground[1]);
 		}
 	}

 	dbItem = new ToolItem(toolBar, SWT.CHECK);
 	dbItem.setText(getResourceString("DoubleBuffer")); //$NON-NLS-1$
 	dbItem.setImage(loadImage(display, "db.gif")); //$NON-NLS-1$

 	ToolItem separator = new ToolItem(toolBar, SWT.SEPARATOR);
 	Composite comp = new Composite(toolBar, SWT.NONE);
 	GridData data;
 	GridLayout layout = new GridLayout(1, false);
 	layout.verticalSpacing = 0;
 	layout.marginWidth = layout.marginHeight = 3;
 	comp.setLayout(layout);
 	timerSpinner = new Spinner(comp, SWT.BORDER | SWT.WRAP);
 	data = new GridData(SWT.CENTER, SWT.CENTER, false, false);
 	timerSpinner.setLayoutData(data);
 	Label label = new Label(comp, SWT.NONE);
 	label.setText(getResourceString("Animation")); //$NON-NLS-1$
 	data = new GridData(SWT.CENTER, SWT.CENTER, false, false);
 	label.setLayoutData(data);
 	timerSpinner.setMaximum(1000);
 	timerSpinner.setSelection(TIMER);
 	timerSpinner.setSelection(TIMER);
 	separator.setControl(comp);
 	separator.setWidth(comp.computeSize(SWT.DEFAULT, SWT.DEFAULT).x);
 }

 Image createImage(Display display, Color color) {
 	Image image = new Image(display, 16, 16);
 	GC gc = new GC(image);
 	gc.setBackground(color);
 	Rectangle rect = image.getBounds();
 	gc.fillRectangle(rect);
 	if (color.equals(display.getSystemColor(SWT.COLOR_BLACK))) {
 		gc.setForeground(display.getSystemColor(SWT.COLOR_WHITE));
 	}
 	gc.drawRectangle(rect.x, rect.y, rect.width - 1, rect.height - 1);
 	gc.dispose();
 	return image;
 }

 void createTabList(Composite parent) {
 	tabList = new Tree(parent, SWT.SINGLE | SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
 	HashSet set = new HashSet();
 	for (int i = 0; i < tabs.length; i++) {
 		GraphicsTab tab = tabs[i];
 		set.add(tab.getCategory());
 	}
 	for (Iterator iter = set.iterator(); iter.hasNext();) {
 		String text = (String) iter.next();
 		TreeItem item = new TreeItem(tabList, SWT.NONE);
 		item.setText(text);
 	}
 	TreeItem[] items = tabList.getItems();
 	for (int i = 0; i < items.length; i++) {
 		TreeItem item = items[i];
 		for (int j = 0; j < tabs.length; j++) {
 			GraphicsTab tab = tabs[j];
 			if (item.getText().equals(tab.getCategory())) {
 				TreeItem item1 = new TreeItem(item, SWT.NONE);
 				item1.setText(tab.getText());
 				item1.setData(tab);
 			}
 		}
 	}
 	tabList.addListener(SWT.Selection, new Listener() {
 		public void handleEvent(Event event) {
 			TreeItem item = (TreeItem)event.item;
 			if (item != null) {
 				setTab((GraphicsTab)item.getData());
 			}
 		}
 	});
 }

 GraphicsTab[] createTabs() {
 	return new GraphicsTab[] {
 		new LineTab(this),
 		new StarPolyTab(this),
 		tab = new IntroTab(this),
 		new BlackHoleTab(this),
 	};
 }

 /**
  * Disposes all resources created by the receiver.
  */
 public void dispose() {
 	if (tabs != null) {
 		for (int i = 0; i < tabs.length; i++) {
 			GraphicsTab tab = tabs[i];
 			tab.dispose();
 		}
 	}
 	tabs = null;
 	if (images != null) {
 		for (int i = 0; i < images.size(); i++) {
 			((Image)images.elementAt(i)).dispose();
 		}
 	}
 	images = null;
 	if (customColor != null) customColor.dispose();
 	customColor = null;
 	if (customImage != null) customImage.dispose();
 	customImage = null;
 }

 TreeItem findItemByData(TreeItem[] items, Object data) {
 	for (int i = 0; i < items.length; i++) {
 		TreeItem item = items[i];
 		if (item.getData() == data) return item;
 		item = findItemByData(item.getItems(), data);
 		if (item != null) return item;
 	}
 	return null;
 }

 /**
  * Gets the current tab.
  */
 public GraphicsTab getTab() {
 	return tab;
 }

 Listener getRedrawListener() {
 	return redrawListener;
 }

 /**
  * Gets a string from the resource bundle.
  * We don't want to crash because of a missing String.
  * Returns the key if not found.
  */
 static String getResourceString(String key) {
 	try {
 		return RESOURCE_BUNDLE.getString(key);
 	} catch (MissingResourceException e) {
 		return key;
 	} catch (NullPointerException e) {
 		return "!" + key + "!"; //$NON-NLS-1$ //$NON-NLS-2$
 	}
 }

 static Image loadImage (Display display, Class clazz, String string) {
 	InputStream stream = clazz.getResourceAsStream (string);
 	if (stream == null) return null;
 	Image image = null;
 	try {
 		image = new Image (display, stream);
 	} catch (SWTException ex) {
 	} finally {
 		try {
 			stream.close ();
 		} catch (IOException ex) {}
 	}
 	return image;
 }

 Image loadImage(Display display, String name) {
 	Image image = loadImage(display, GraphicsExample.class, name);
 	if (image != null) images.addElement(image);
 	return image;
 }

 void paintBackground(GC gc, Rectangle rect) {
 	gc.setBackground((Color)tabBackground[0]);
 	gc.fillRectangle(rect);
 }

 /**
  * Redraws the current tab.
  */
 public void redraw() {
 	canvas.redraw();
 }

 /**
  * Grabs input focus.
  */
 public void setFocus() {
 	tabList.setFocus();
 }

 /**
  * Sets the current tab.
  */
 public void setTab(GraphicsTab tab) {
 	this.tab = tab;
 	Control[] children = controlPanel.getChildren();
 	for (int i = 0; i < children.length; i++) {
 		Control control = children[i];
 		control.dispose();
 	}
 	if (tab != null) {
 		tab.createControlPanel(controlPanel);
 		animate = tab.isAnimated();
 	}
 	playItem.setEnabled(!animate);
 	pauseItem.setEnabled(animate);
 	GridData data = (GridData)controlPanel.getLayoutData();
 	children = controlPanel.getChildren();
 	data.exclude = children.length == 0;
 	controlPanel.setVisible(!data.exclude);
 	if (data.exclude) {
 		tabPanel.layout();
 	} else {
 		tabPanel.layout(children);
 	}
 	if (tab != null) {
 		TreeItem[] selection = tabList.getSelection();
 		if (selection.length == 0 || selection[0].getData() != tab) {
 			TreeItem item = findItemByData(tabList.getItems(), tab);
 			if (item != null) tabList.setSelection(new TreeItem[]{item});
 		}
 	}
 	canvas.redraw();
 }

 void startAnimationTimer() {
 	final Display display = Display.getCurrent();
 	display.timerExec(timerSpinner.getSelection(), new Runnable() {
 		public void run() {
 			if (canvas.isDisposed()) return;
 			if (animate) {
 				GraphicsTab tab = getTab();
 				if (tab != null && tab.isAnimated()) {
 					Rectangle rect = canvas.getClientArea();
 					tab.next(rect.width, rect.height);
 					canvas.redraw();
 					canvas.update();
 				}
 			}
 			display.timerExec(timerSpinner.getSelection(), this);
 		}
 	});
 }

 public static void main(String[] args) {
 	Display display = new Display();
 	Shell shell = new Shell(display);
 	shell.setText(getResourceString("SWTGraphics")); //$NON-NLS-1$
 	final GraphicsExample example = new GraphicsExample(shell);
 	shell.addListener(SWT.Close, new Listener() {
 		public void handleEvent(Event event) {
 			example.dispose();
 		}
 	});
 	shell.open();
 	while (!shell.isDisposed()) {
 		if (!display.readAndDispatch()) display.sleep();
 	}
 }
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2005 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 java.io.IOException;
	import java.io.InputStream;
	import java.util.HashSet;
	import java.util.Iterator;
	import java.util.MissingResourceException;
	import java.util.ResourceBundle;
	import java.util.Vector;

	import org.eclipse.swt.*;
	import org.eclipse.swt.graphics.*;
	import org.eclipse.swt.layout.*;
	import org.eclipse.swt.widgets.*;

	public class GraphicsExample {

	Composite parent;
	GraphicsTab[] tabs;
	GraphicsTab tab;
	Object[] tabBackground;

	boolean animate;

	Listener redrawListener;

	ToolBar toolBar;
	Tree tabList;
	Canvas canvas;
	Composite controlPanel, tabPanel;
	ToolItem playItem, pauseItem, backItem, dbItem;
	Spinner timerSpinner;

	Menu backMenu;
	MenuItem customMI;
	Image customImage;
	Color customColor;

	Vector images;

	static boolean advanceGraphics, advanceGraphicsInit;

	static final int TIMER = 30;
	static final ResourceBundle RESOURCE_BUNDLE = ResourceBundle.getBundle("examples_graphics"); //$NON-NLS-1$

	public GraphicsExample(final Composite parent) {
	this.parent = parent;
	redrawListener = new Listener() {
	public void handleEvent(Event e) {
	redraw();
	}
	};
	GridData data;
	GridLayout layout = new GridLayout(3, false);
	layout.horizontalSpacing = 1;
	parent.setLayout(layout);
	tabs = createTabs();
	images = new Vector();
	createToolBar(parent);
	createTabList(parent);
	final Sash sash = new Sash(parent, SWT.VERTICAL);
	createTabPanel(parent);
	data = new GridData(SWT.FILL, SWT.CENTER, true, false);
	data.horizontalSpan = 3;
	toolBar.setLayoutData(data);
	data = new GridData(SWT.CENTER, SWT.FILL, false, true);
	data.widthHint = tabList.computeSize(SWT.DEFAULT, SWT.DEFAULT).x + 50;
	tabList.setLayoutData(data);
	data = new GridData(SWT.CENTER, SWT.FILL, false, true);
	sash.setLayoutData(data);
	data = new GridData(SWT.FILL, SWT.FILL, true, true);
	tabPanel.setLayoutData(data);
	sash.addListener(SWT.Selection, new Listener() {
	public void handleEvent(Event event) {
	if (event.detail != SWT.DRAG) {
	GridData data = (GridData)tabList.getLayoutData();
	data.widthHint = event.x - tabList.computeTrim(0, 0, 0, 0).width;
	parent.layout(true);
	animate = pauseItem.getEnabled();
	} else {
	animate = false;
	}
	}
	});
	setTab(tab);
	startAnimationTimer();
	}

	boolean checkAdvancedGraphics() {
	if (advanceGraphicsInit) return advanceGraphics;
	advanceGraphicsInit = true;
	Display display = Display.getCurrent();
	try {
	Path path = new Path(display);
	path.dispose();
	} catch (SWTException e) {
	Shell shell = display.getActiveShell(), newShell = null;
	if (shell == null) shell = newShell = new Shell(display);
	MessageBox dialog = new MessageBox(shell, SWT.ICON_WARNING \| SWT.OK);
	dialog.setText(RESOURCE_BUNDLE.getString("Warning")); //$NON-NLS-1$
	dialog.setMessage(RESOURCE_BUNDLE.getString("LibNotFound")); //$NON-NLS-1$
	dialog.open();
	if (newShell != null) newShell.dispose();
	return false;
	}
	return advanceGraphics = true;
	}

	void createCanvas(Composite parent) {
	canvas = new Canvas(parent, SWT.NO_BACKGROUND);
	canvas.addListener(SWT.Paint, new Listener() {
	public void handleEvent(Event event) {
	GC gc;
	Rectangle rect = canvas.getClientArea();
	Image buffer = null;
	if (dbItem.getSelection()) {
	buffer = new Image(canvas.getDisplay(), rect);
	gc = new GC(buffer);
	} else {
	gc = event.gc;
	}
	paintBackground(gc, rect);
	GraphicsTab tab = getTab();
	if (tab != null) tab.paint(gc, rect.width, rect.height);
	if (gc != event.gc) gc.dispose();
	if (buffer != null) {
	event.gc.drawImage(buffer, 0, 0);
	buffer.dispose();
	}
	}
	});
	}

	void createControlPanel(Composite parent) {
	Group group;
	controlPanel = group = new Group(parent, SWT.NONE);
	group.setText(getResourceString("Settings")); //$NON-NLS-1$
	controlPanel.setLayout(new RowLayout());
	}

	void createTabPanel(Composite parent) {
	tabPanel = new Composite(parent, SWT.NONE);
	GridData data;
	GridLayout layout = new GridLayout(1, false);
	layout.marginHeight = layout.marginWidth = 0;
	tabPanel.setLayout(layout);
	createCanvas(tabPanel);
	createControlPanel(tabPanel);
	data = new GridData(SWT.FILL, SWT.FILL, true, true);
	canvas.setLayoutData(data);
	data = new GridData(SWT.FILL, SWT.CENTER, true, false);
	controlPanel.setLayoutData(data);
	}

	void createToolBar(final Composite parent) {
	final Display display = parent.getDisplay();

	toolBar = new ToolBar(parent, SWT.FLAT);
	Listener toolBarListener = new Listener() {
	public void handleEvent(Event event) {
	switch (event.type) {
	case SWT.Selection: {
	if (event.widget == playItem) {
	animate = true;
	playItem.setEnabled(!animate);
	pauseItem.setEnabled(animate);
	} else if (event.widget == pauseItem) {
	animate = false;
	playItem.setEnabled(!animate);
	pauseItem.setEnabled(animate);
	} else if (event.widget == backItem) {
	final ToolItem toolItem = (ToolItem) event.widget;
	final ToolBar toolBar = toolItem.getParent();
	Rectangle toolItemBounds = toolItem.getBounds();
	Point point = toolBar.toDisplay(new Point(toolItemBounds.x, toolItemBounds.y));
	backMenu.setLocation(point.x, point.y + toolItemBounds.height);
	backMenu.setVisible(true);
	}
	}
	break;
	}
	}
	};

	playItem = new ToolItem(toolBar, SWT.PUSH);
	playItem.setText(getResourceString("Play")); //$NON-NLS-1$
	playItem.setImage(loadImage(display, "play.gif")); //$NON-NLS-1$
	playItem.addListener(SWT.Selection, toolBarListener);

	pauseItem = new ToolItem(toolBar, SWT.PUSH);
	pauseItem.setText(getResourceString("Pause")); //$NON-NLS-1$
	pauseItem.setImage(loadImage(display, "pause.gif")); //$NON-NLS-1$
	pauseItem.addListener(SWT.Selection, toolBarListener);

	backItem = new ToolItem(toolBar, SWT.PUSH);
	backItem.setText(getResourceString("Background")); //$NON-NLS-1$
	backItem.addListener(SWT.Selection, toolBarListener);
	String[] names = new String[]{
	getResourceString("White"), //$NON-NLS-1$
	getResourceString("Black"), //$NON-NLS-1$
	getResourceString("Red"), //$NON-NLS-1$
	getResourceString("Green"), //$NON-NLS-1$
	getResourceString("Blue"), //$NON-NLS-1$
	getResourceString("CustomColor"), //$NON-NLS-1$
	};
	Color[] colors = new Color[]{
	display.getSystemColor(SWT.COLOR_WHITE),
	display.getSystemColor(SWT.COLOR_BLACK),
	display.getSystemColor(SWT.COLOR_RED),
	display.getSystemColor(SWT.COLOR_GREEN),
	display.getSystemColor(SWT.COLOR_BLUE),
	null,
	};
	backMenu = new Menu(parent);
	Listener listener = new Listener() {
	public void handleEvent(Event event) {
	MenuItem item = (MenuItem)event.widget;
	if (customMI == item) {
	ColorDialog dialog = new ColorDialog(parent.getShell());
	RGB rgb = dialog.open();
	if (rgb == null) return;
	if (customColor != null) customColor.dispose();
	customColor = new Color(display, rgb);
	if (customImage != null) customImage.dispose();
	customImage = createImage(display, customColor);
	item.setData(new Object[]{customColor, customImage});
	item.setImage(customImage);
	}
	tabBackground = (Object[])item.getData();
	backItem.setImage((Image)tabBackground[1]);
	canvas.redraw();
	}
	};
	for (int i = 0; i < names.length; i++) {
	MenuItem item = new MenuItem(backMenu, SWT.NONE);
	item.setText(names[i]);
	item.addListener(SWT.Selection, listener);
	Image image = null;
	if (colors[i] != null) {
	image = createImage(display, colors[i]);
	images.addElement(image);
	item.setImage(image);
	} else {
	// custom menu item
	customMI = item;
	}
	item.setData(new Object[]{colors[i], image});
	if (tabBackground == null) {
	tabBackground = (Object[])item.getData();
	backItem.setImage((Image)tabBackground[1]);
	}
	}

	dbItem = new ToolItem(toolBar, SWT.CHECK);
	dbItem.setText(getResourceString("DoubleBuffer")); //$NON-NLS-1$
	dbItem.setImage(loadImage(display, "db.gif")); //$NON-NLS-1$

	ToolItem separator = new ToolItem(toolBar, SWT.SEPARATOR);
	Composite comp = new Composite(toolBar, SWT.NONE);
	GridData data;
	GridLayout layout = new GridLayout(1, false);
	layout.verticalSpacing = 0;
	layout.marginWidth = layout.marginHeight = 3;
	comp.setLayout(layout);
	timerSpinner = new Spinner(comp, SWT.BORDER \| SWT.WRAP);
	data = new GridData(SWT.CENTER, SWT.CENTER, false, false);
	timerSpinner.setLayoutData(data);
	Label label = new Label(comp, SWT.NONE);
	label.setText(getResourceString("Animation")); //$NON-NLS-1$
	data = new GridData(SWT.CENTER, SWT.CENTER, false, false);
	label.setLayoutData(data);
	timerSpinner.setMaximum(1000);
	timerSpinner.setSelection(TIMER);
	timerSpinner.setSelection(TIMER);
	separator.setControl(comp);
	separator.setWidth(comp.computeSize(SWT.DEFAULT, SWT.DEFAULT).x);
	}

	Image createImage(Display display, Color color) {
	Image image = new Image(display, 16, 16);
	GC gc = new GC(image);
	gc.setBackground(color);
	Rectangle rect = image.getBounds();
	gc.fillRectangle(rect);
	if (color.equals(display.getSystemColor(SWT.COLOR_BLACK))) {
	gc.setForeground(display.getSystemColor(SWT.COLOR_WHITE));
	}
	gc.drawRectangle(rect.x, rect.y, rect.width - 1, rect.height - 1);
	gc.dispose();
	return image;
	}

	void createTabList(Composite parent) {
	tabList = new Tree(parent, SWT.SINGLE \| SWT.H_SCROLL \| SWT.V_SCROLL \| SWT.BORDER);
	HashSet set = new HashSet();
	for (int i = 0; i < tabs.length; i++) {
	GraphicsTab tab = tabs[i];
	set.add(tab.getCategory());
	}
	for (Iterator iter = set.iterator(); iter.hasNext();) {
	String text = (String) iter.next();
	TreeItem item = new TreeItem(tabList, SWT.NONE);
	item.setText(text);
	}
	TreeItem[] items = tabList.getItems();
	for (int i = 0; i < items.length; i++) {
	TreeItem item = items[i];
	for (int j = 0; j < tabs.length; j++) {
	GraphicsTab tab = tabs[j];
	if (item.getText().equals(tab.getCategory())) {
	TreeItem item1 = new TreeItem(item, SWT.NONE);
	item1.setText(tab.getText());
	item1.setData(tab);
	}
	}
	}
	tabList.addListener(SWT.Selection, new Listener() {
	public void handleEvent(Event event) {
	TreeItem item = (TreeItem)event.item;
	if (item != null) {
	setTab((GraphicsTab)item.getData());
	}
	}
	});
	}

	GraphicsTab[] createTabs() {
	return new GraphicsTab[] {
	new LineTab(this),
	new StarPolyTab(this),
	tab = new IntroTab(this),
	new BlackHoleTab(this),
	};
	}

	/**
	* Disposes all resources created by the receiver.
	*/
	public void dispose() {
	if (tabs != null) {
	for (int i = 0; i < tabs.length; i++) {
	GraphicsTab tab = tabs[i];
	tab.dispose();
	}
	}
	tabs = null;
	if (images != null) {
	for (int i = 0; i < images.size(); i++) {
	((Image)images.elementAt(i)).dispose();
	}
	}
	images = null;
	if (customColor != null) customColor.dispose();
	customColor = null;
	if (customImage != null) customImage.dispose();
	customImage = null;
	}

	TreeItem findItemByData(TreeItem[] items, Object data) {
	for (int i = 0; i < items.length; i++) {
	TreeItem item = items[i];
	if (item.getData() == data) return item;
	item = findItemByData(item.getItems(), data);
	if (item != null) return item;
	}
	return null;
	}

	/**
	* Gets the current tab.
	*/
	public GraphicsTab getTab() {
	return tab;
	}

	Listener getRedrawListener() {
	return redrawListener;
	}

	/**
	* Gets a string from the resource bundle.
	* We don't want to crash because of a missing String.
	* Returns the key if not found.
	*/
	static String getResourceString(String key) {
	try {
	return RESOURCE_BUNDLE.getString(key);
	} catch (MissingResourceException e) {
	return key;
	} catch (NullPointerException e) {
	return "!" + key + "!"; //$NON-NLS-1$ //$NON-NLS-2$
	}
	}

	static Image loadImage (Display display, Class clazz, String string) {
	InputStream stream = clazz.getResourceAsStream (string);
	if (stream == null) return null;
	Image image = null;
	try {
	image = new Image (display, stream);
	} catch (SWTException ex) {
	} finally {
	try {
	stream.close ();
	} catch (IOException ex) {}
	}
	return image;
	}

	Image loadImage(Display display, String name) {
	Image image = loadImage(display, GraphicsExample.class, name);
	if (image != null) images.addElement(image);
	return image;
	}

	void paintBackground(GC gc, Rectangle rect) {
	gc.setBackground((Color)tabBackground[0]);
	gc.fillRectangle(rect);
	}

	/**
	* Redraws the current tab.
	*/
	public void redraw() {
	canvas.redraw();
	}

	/**
	* Grabs input focus.
	*/
	public void setFocus() {
	tabList.setFocus();
	}

	/**
	* Sets the current tab.
	*/
	public void setTab(GraphicsTab tab) {
	this.tab = tab;
	Control[] children = controlPanel.getChildren();
	for (int i = 0; i < children.length; i++) {
	Control control = children[i];
	control.dispose();
	}
	if (tab != null) {
	tab.createControlPanel(controlPanel);
	animate = tab.isAnimated();
	}
	playItem.setEnabled(!animate);
	pauseItem.setEnabled(animate);
	GridData data = (GridData)controlPanel.getLayoutData();
	children = controlPanel.getChildren();
	data.exclude = children.length == 0;
	controlPanel.setVisible(!data.exclude);
	if (data.exclude) {
	tabPanel.layout();
	} else {
	tabPanel.layout(children);
	}
	if (tab != null) {
	TreeItem[] selection = tabList.getSelection();
	if (selection.length == 0 \|\| selection[0].getData() != tab) {
	TreeItem item = findItemByData(tabList.getItems(), tab);
	if (item != null) tabList.setSelection(new TreeItem[]{item});
	}
	}
	canvas.redraw();
	}

	void startAnimationTimer() {
	final Display display = Display.getCurrent();
	display.timerExec(timerSpinner.getSelection(), new Runnable() {
	public void run() {
	if (canvas.isDisposed()) return;
	if (animate) {
	GraphicsTab tab = getTab();
	if (tab != null && tab.isAnimated()) {
	Rectangle rect = canvas.getClientArea();
	tab.next(rect.width, rect.height);
	canvas.redraw();
	canvas.update();
	}
	}
	display.timerExec(timerSpinner.getSelection(), this);
	}
	});
	}

	public static void main(String[] args) {
	Display display = new Display();
	Shell shell = new Shell(display);
	shell.setText(getResourceString("SWTGraphics")); //$NON-NLS-1$
	final GraphicsExample example = new GraphicsExample(shell);
	shell.addListener(SWT.Close, new Listener() {
	public void handleEvent(Event event) {
	example.dispose();
	}
	});
	shell.open();
	while (!shell.isDisposed()) {
	if (!display.readAndDispatch()) display.sleep();
	}
	}
	}