SWT is a cross-platform GUI library for JVM based desktop applications. The best known SWT-based application is Eclipse.
For more information about SWT, visit the official SWT page.
SWT comes with platform-specific jar files. Download them from https://download.eclipse.org/eclipse/downloads and add the jar file to your classpath.
import org.eclipse.swt.SWT; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Text; public class HelloWorld { public static void main(String[] args) { final Display display = new Display(); final Shell shell = new Shell(display); shell.setText("Hello World"); shell.setLayout(new GridLayout(2, false)); final Label label = new Label(shell, SWT.LEFT); label.setText("Your &Name:"); label.setLayoutData(new GridData(SWT.FILL, SWT.CENTER, false, false)); final Text text = new Text(shell, SWT.BORDER | SWT.SINGLE); final GridData data = new GridData(SWT.FILL, SWT.CENTER, true, false); data.minimumWidth = 120; text.setLayoutData(data); final Button button = new Button(shell, SWT.PUSH); button.setText("Say Hello"); shell.setDefaultButton(button); button.setLayoutData(new GridData(SWT.END, SWT.CENTER, false, false, 2, 1)); final Label output = new Label(shell, SWT.CENTER); output.setLayoutData(new GridData(SWT.FILL, SWT.CENTER, true, false, 2, 1)); button.addListener(SWT.Selection, event -> { String name = text.getText().trim(); if (name.length() == 0) { name = "world"; } output.setText("Hello " + name + "!"); }); shell.setSize(shell.computeSize(SWT.DEFAULT, SWT.DEFAULT)); shell.open(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) { display.sleep(); } } display.dispose(); } }
First, a Display is created which is something like the central place of all GUI-related code.
Then a Shell is created which in our example is a top-level window.
Then all child controls and listeners are created, including their layout information.
Finally, we set the window's size determines by its child controls and open the window.
The while-loop processes all GUI related events until the shell is disposed which happens when closing.
Before exiting, any claimed GUI resources needs to be freed.
Thanks for your interest in this project.
For information about contributing to Eclipse Platform in general, see the general CONTRIBUTING page.
The SWT source code is stored in this Git repository.
This repository uses the Git Large File Storage (LFS) extension to host also the precompiled SWT native binaries, which is therefore required unless binaries are compiled locally.
When using Git from the CLI follow the Git LFS installation and setup instructions:
When using EGit from within Eclipse follow the EGit user guide on GIT LFS Support:
Note:
Changes to the binary artifacts must not be committed, as the binaries are compiled only in the Eclipse infrastructure.
To build all SWT artifacts and to run all tests, execute at the CLI from the repository root:
mvn clean verify
To build only the artifacts, without testing, run
mvn clean verify -DskipTests
For instructions on building the native binaries of SWT see the section Building native binaries.
See the following description for how to contribute a feature or a bug fix to SWT.
Information regarding source code management, builds, coding standards, and more can be found under the following link.
Also see in the SWT section of the Eclipse FAQ for more background information about SWT.
Before your contribution can be accepted by the project, you need to create and electronically sign the Eclipse Foundation Contributor License Agreement (CLA).
Contact the project developers via GitHub:
- GitHub Discussions - For questions and general discussions
- GitHub Issues - For bug reports and feature requests
You can register bugs and feature requests in the GitHub Issue Tracker. Remember that contributions are always welcome!
Please bear in mind that this project is almost entirely developed by volunteers. If you do not provide the implementation yourself (or pay someone to do it for you), the bug might never get fixed. If it is a serious bug, other people than you might care enough to provide a fix.
Note: SWT used to track ongoing development and issues in Bugzilla, but we now use GitHub Issues and Discussions.
In project Initiative 31 an evaluation on the feasibility of implementing SWT in an OS-agnostic way based on a cross-platform graphics/widgets library has been conducted. The goal was to assess if the existing three implementations could eventually be replaced by an OS-agnostic one in order to reduce maintenance efforts, enable highly customizable look and feel, and improve configurability. A demonstrator based on the graphics library Skia was implemented and multiple prototypes for mitigating risks have been implemented, such that bringing that to a production-ready implementation is a matter of effort but not of conceptual or technical/technological risk.
The actual prototyping work has started on four technologies: Skia with Visual Class Library (VCL), Skia with custom-implemented widgets, GTK, and Swing
All those prototypes can be found in the according GitHub organization: https://github.com/swt-initiative31
The work finally focused on the Skia graphics library with custom-implemented widgets: https://github.com/swt-initiative31/prototype-skija
The project concluded with the feasibility demonstration and a report summarizing the results. Given sufficient resources, a follow-up project could convert the demonstrator into a production-ready state.