Examples

The following Java code defines an undoable action that changes the unit system used in a drawing editor.

public class SetUnit extends ActionImpl implements Undoable {
	private Unit unit;
	private Unit oldUnit;

	@Override
	public boolean canDo() { // Checks whether the action can be executed
		return unit != null;
	}
	
	@Override
	protected void doActionBody() { // Execution of the action.
		oldUnit = ScaleRuler.getUnit();
		redo();
	}
	
	@Override
	public void undo() { // Undoes the action
		ScaleRuler.setUnit(oldUnit);
	}

	@Override
	public void redo() { // Redoes the action
		ScaleRuler.setUnit(unit);
	}

	@Override
	public String getUndoName() { // Provides a short textual description of this undoable action.
		return "Changing the unit";
	}
    //...
}

This action can be then used in an instrument to be binded to a predefined user interaction and widgets.

// An instrument is a controller/presenter/viewModel/component/etc: 
// it gather events produced by widgets as user interactions into actions that modify the system.
public class PreferencesSetter extends JfxInstrument implements Initializable {
    @FXML private ComboBox<String> unitChoice;
    //...

    @Override
    protected void configureBindings() throws IllegalAccessException, InstantiationException {
        //...
        // Defines an widget binding that binds a combobox to the action SetUnit
        bindComboBox(SetUnit.class,  // The type of the action to produce
            action -> action.setUnit(Unit.getUnit(unitChoice.getSelectionModel().getSelectedItem())), // The initialisation of the action
            unitChoice); // The source widget to listen
    }
}

Implementations

Malai fully supports Java Swing and JavaFX. A TypeScript/Javascript version is in progress.

How to use

As Maven libraries. In your POM file, adds the Malai repositories:

    <repositories>
        <repository>
            <id>mavenInriaSnapshot</id>
            <name>http://maven.inria.fr-snapshots</name>
            <url>http://maven.inria.fr/artifactory/malai-public-snapshot</url>
        </repository>
        <repository>
            <id>mavenInriaRelease</id>
            <name>http://maven.inria.fr-releases</name>
            <url>http://maven.inria.fr/artifactory/malai-public-release</url>
        </repository>
    </repositories>

And adds the dependencies:

        <dependency>
            <groupId>org.malai</groupId>
            <artifactId>malai.core</artifactId>
            <version>3.0-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.malai</groupId>
            <artifactId>malai.javafx</artifactId>
            <version>3.0-SNAPSHOT</version>
        </dependency>

Who uses Malai?

Latexdraw is a vector drawing editors for LaTeX. It is developed on the top of Malai JavaFX.