Java Tutorial/SWT/ProgressBar — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
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Версия 20:44, 31 мая 2010
Содержание
Introducing ProgressBar
Progress bars display incremental progress. ProgressBar Styles:
StyleDescriptionSWT.SMOOTHCreates a progress bar that displays a continuous bar as its indicator. The default is to display a distinctly divided bar.SWT.HORIZONTALCreates a horizontal progress bar.SWT.VERTICALCreates a vertical progress bar.SWT.INDETERMINATECreates a progress bar that constantly cycles, indicating continuous work.
Update a progress bar from another thread
<source lang="java">
/*******************************************************************************
* Copyright (c) 2000, 2004 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 *******************************************************************************/
import org.eclipse.swt.SWT; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.ProgressBar; import org.eclipse.swt.widgets.Shell; public class ProgressBarUpdateAnotherThread {
public static void main(String[] args) { final Display display = new Display(); Shell shell = new Shell(display); final ProgressBar bar = new ProgressBar(shell, SWT.SMOOTH); bar.setBounds(10, 10, 200, 32); shell.open(); final int maximum = bar.getMaximum(); new Thread() { public void run() { for (final int[] i = new int[1]; i[0] <= maximum; i[0]++) { try { Thread.sleep(100); } catch (Throwable th) { } if (display.isDisposed()) return; display.asyncExec(new Runnable() { public void run() { if (bar.isDisposed()) return; bar.setSelection(i[0]); } }); } } }.start(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } display.dispose(); }
}</source>
Update a progress bar from the UI thread
<source lang="java">
import org.eclipse.swt.SWT; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.ProgressBar; import org.eclipse.swt.widgets.Shell; public class ProgressBarUpdateUIThread {
public static void main(String[] args) { Display display = new Display(); Shell shell = new Shell(display); ProgressBar bar = new ProgressBar(shell, SWT.SMOOTH); bar.setBounds(10, 10, 200, 32); shell.open(); for (int i = 0; i <= bar.getMaximum(); i++) { try { Thread.sleep(100); } catch (Throwable th) { } bar.setSelection(i); } while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } display.dispose(); }
}</source>
Using the SWT.INDETERMINATE style: the operation is happening but doesn"t know when it"ll finish.
<source lang="java">
import org.eclipse.swt.SWT; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.ProgressBar; import org.eclipse.swt.widgets.Shell; public class ProgressBarExample {
public static void main(String[] args) { Display display = new Display(); Shell shell = new Shell(display); shell.setLayout(new GridLayout()); // Create an indeterminate ProgressBar ProgressBar pb2 = new ProgressBar(shell, SWT.HORIZONTAL | SWT.INDETERMINATE); pb2.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
shell.open(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) { display.sleep(); } } }
}</source>
Using Thread to update ProgressBar value
<source lang="java">
import org.eclipse.swt.SWT; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.ProgressBar; import org.eclipse.swt.widgets.Shell; public class ProgressBarExample {
public static void main(String[] args) { Display display = new Display(); Shell shell = new Shell(display); shell.setLayout(new GridLayout()); // Create a smooth ProgressBar ProgressBar pb1 = new ProgressBar(shell, SWT.HORIZONTAL | SWT.SMOOTH); pb1.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); pb1.setMinimum(0); pb1.setMaximum(30); // Start the first ProgressBar new LongRunningOperation(display, pb1).start(); shell.open(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) { display.sleep(); } } }
} class LongRunningOperation extends Thread {
private Display display; private ProgressBar progressBar; public LongRunningOperation(Display display, ProgressBar progressBar) { this.display = display; this.progressBar = progressBar; } public void run() { for (int i = 0; i < 30; i++) { try { Thread.sleep(1000); } catch (InterruptedException e) { } display.asyncExec(new Runnable() { public void run() { if (progressBar.isDisposed()) return; progressBar.setSelection(progressBar.getSelection() + 1); } }); } }
}</source>