graphicsexample.java

一个简单的UNCODE 码生成程序

			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();
	}
}
}