List of usage examples for org.eclipse.swt.widgets Canvas isDisposed
public boolean isDisposed()
true if the widget has been disposed, and false otherwise. From source file:org.eclipse.swt.snippets.Snippet275.java
public static void main(String[] args) { final int INTERVAL = 888; final Display display = new Display(); final Image image = new Image(display, 750, 750); GC gc = new GC(image); gc.setBackground(display.getSystemColor(SWT.COLOR_RED)); gc.fillRectangle(image.getBounds()); gc.dispose();//from w w w .j av a 2s . c o m Shell shell = new Shell(display); shell.setText("Snippet 275"); shell.setBounds(10, 10, 790, 790); final Canvas canvas = new Canvas(shell, SWT.NONE); canvas.setBounds(10, 10, 750, 750); canvas.addListener(SWT.Paint, event -> { value = String.valueOf(System.currentTimeMillis()); event.gc.drawImage(image, 0, 0); event.gc.drawString(value, 10, 10, true); }); display.timerExec(INTERVAL, new Runnable() { @Override public void run() { if (canvas.isDisposed()) return; // canvas.redraw (); // <-- bad, damages more than is needed GC gc = new GC(canvas); Point extent = gc.stringExtent(value + '0'); gc.dispose(); canvas.redraw(10, 10, extent.x, extent.y, false); display.timerExec(INTERVAL, this); } }); shell.open(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } image.dispose(); display.dispose(); }
From source file:org.eclipse.swt.snippets.Snippet174.java
public static void main(String[] args) { Display display = new Display(); Shell shell = new Shell(display); shell.setText("OpenGL in SWT"); shell.setLayout(new FillLayout()); final Canvas canvas = new Canvas(shell, SWT.NO_BACKGROUND); canvas.addControlListener(new ControlAdapter() { public void controlResized(ControlEvent e) { resize(canvas);//from ww w. ja v a 2 s . co m } }); final GLContext context = init(canvas); shell.addDisposeListener(new DisposeListener() { public void widgetDisposed(DisposeEvent e) { context.dispose(); } }); new Runnable() { public void run() { if (canvas.isDisposed()) return; render(); context.swapBuffers(); canvas.getDisplay().timerExec(50, this); } }.run(); shell.open(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } display.dispose(); }
From source file:BrowserExample.java
/** * Creates an instance of a ControlExample embedded inside the supplied * parent Composite./* w w w .j av a 2 s.c om*/ * * @param parent * the container of the example */ public BrowserExample(Composite parent) { final Display display = parent.getDisplay(); FormLayout layout = new FormLayout(); parent.setLayout(layout); ToolBar toolbar = new ToolBar(parent, SWT.NONE); final ToolItem itemBack = new ToolItem(toolbar, SWT.PUSH); itemBack.setText(getResourceString("Back")); final ToolItem itemForward = new ToolItem(toolbar, SWT.PUSH); itemForward.setText(getResourceString("Forward")); final ToolItem itemStop = new ToolItem(toolbar, SWT.PUSH); itemStop.setText(getResourceString("Stop")); final ToolItem itemRefresh = new ToolItem(toolbar, SWT.PUSH); itemRefresh.setText(getResourceString("Refresh")); final ToolItem itemGo = new ToolItem(toolbar, SWT.PUSH); itemGo.setText(getResourceString("Go")); location = new Text(parent, SWT.BORDER); images = new Image[] { new Image(display, "java2s.gif") }; final Canvas canvas = new Canvas(parent, SWT.NO_BACKGROUND); final Rectangle rect = images[0].getBounds(); canvas.addListener(SWT.Paint, new Listener() { public void handleEvent(Event e) { Point pt = canvas.getSize(); e.gc.drawImage(images[index], 0, 0, rect.width, rect.height, 0, 0, pt.x, pt.y); } }); canvas.addListener(SWT.MouseDown, new Listener() { public void handleEvent(Event e) { browser.setUrl(getResourceString("Startup")); } }); display.asyncExec(new Runnable() { public void run() { if (canvas.isDisposed()) return; if (busy) { index++; if (index == images.length) index = 0; canvas.redraw(); } display.timerExec(150, this); } }); final Label status = new Label(parent, SWT.NONE); final ProgressBar progressBar = new ProgressBar(parent, SWT.NONE); FormData data = new FormData(); data.top = new FormAttachment(0, 5); toolbar.setLayoutData(data); data = new FormData(); data.left = new FormAttachment(0, 0); data.right = new FormAttachment(100, 0); data.top = new FormAttachment(canvas, 5, SWT.DEFAULT); data.bottom = new FormAttachment(status, -5, SWT.DEFAULT); try { browser = new Browser(parent, SWT.NONE); browser.setLayoutData(data); } catch (SWTError e) { /* Browser widget could not be instantiated */ Label label = new Label(parent, SWT.CENTER | SWT.WRAP); label.setText(getResourceString("BrowserNotCreated")); label.setLayoutData(data); } data = new FormData(); data.width = 24; data.height = 24; data.top = new FormAttachment(0, 5); data.right = new FormAttachment(100, -5); canvas.setLayoutData(data); data = new FormData(); data.top = new FormAttachment(toolbar, 0, SWT.TOP); data.left = new FormAttachment(toolbar, 5, SWT.RIGHT); data.right = new FormAttachment(canvas, -5, SWT.DEFAULT); location.setLayoutData(data); data = new FormData(); data.left = new FormAttachment(0, 5); data.right = new FormAttachment(progressBar, 0, SWT.DEFAULT); data.bottom = new FormAttachment(100, -5); status.setLayoutData(data); data = new FormData(); data.right = new FormAttachment(100, -5); data.bottom = new FormAttachment(100, -5); progressBar.setLayoutData(data); if (browser != null) { itemBack.setEnabled(browser.isBackEnabled()); itemForward.setEnabled(browser.isForwardEnabled()); Listener listener = new Listener() { public void handleEvent(Event event) { ToolItem item = (ToolItem) event.widget; if (item == itemBack) browser.back(); else if (item == itemForward) browser.forward(); else if (item == itemStop) browser.stop(); else if (item == itemRefresh) browser.refresh(); else if (item == itemGo) browser.setUrl(location.getText()); } }; browser.addLocationListener(new LocationListener() { public void changed(LocationEvent event) { busy = true; if (event.top) location.setText(event.location); } public void changing(LocationEvent event) { } }); browser.addProgressListener(new ProgressListener() { public void changed(ProgressEvent event) { if (event.total == 0) return; int ratio = event.current * 100 / event.total; progressBar.setSelection(ratio); busy = event.current != event.total; if (!busy) { index = 0; canvas.redraw(); } } public void completed(ProgressEvent event) { itemBack.setEnabled(browser.isBackEnabled()); itemForward.setEnabled(browser.isForwardEnabled()); progressBar.setSelection(0); busy = false; index = 0; canvas.redraw(); } }); browser.addStatusTextListener(new StatusTextListener() { public void changed(StatusTextEvent event) { status.setText(event.text); } }); if (parent instanceof Shell) { final Shell shell = (Shell) parent; browser.addTitleListener(new TitleListener() { public void changed(TitleEvent event) { shell.setText(event.title + " - " + getResourceString("window.title")); } }); } itemBack.addListener(SWT.Selection, listener); itemForward.addListener(SWT.Selection, listener); itemStop.addListener(SWT.Selection, listener); itemRefresh.addListener(SWT.Selection, listener); itemGo.addListener(SWT.Selection, listener); location.addListener(SWT.DefaultSelection, new Listener() { public void handleEvent(Event e) { browser.setUrl(location.getText()); } }); initialize(display, browser); browser.setUrl(getResourceString("Startup")); } }