Question

Maybe I missunderstood JavaFX binding or there is a bug in SimpleStringProperty.

When I run this testcode my changed model value didn’t get the new value. Test testBindingToModel fails. I thought my model should then be updated with the value of the TextField tf. But only the binding value of prop1Binding gets the value “test”.

public class BindingTest {  
    private TextField tf;
    private Model model;
    private ModelBinding mb;

    @Before
    public void prepare() {
        tf = new TextField();
        model = new Model();
        mb = new ModelBinding(model);
        Bindings.bindBidirectional(tf.textProperty(), mb.prop1Binding);
    }

    @Test
    public void testBindingToMB() {
        tf.setText("test");

        assertEquals(tf.getText(), mb.prop1Binding.get());
    }

    @Test
    public void testBindingToModel() {
        tf.setText("test");

        assertEquals(tf.getText(), mb.prop1Binding.get());
        assertEquals(tf.getText(), model.getProp1());
    }

    private static class ModelBinding {
        private final StringProperty prop1Binding;

        public ModelBinding(Model model) {
            prop1Binding = new SimpleStringProperty(model, "prop1");
        }

    }

    private static class Model {
        private String prop1;

        public String getProp1() {
            return prop1;
        }

        public void setProp1(String prop1) {
            this.prop1 = prop1;
        }       
    }
    }

Thanks for your help.

Best regards
Sebastian

EDIT:
With this class I can set the value of the model directly. I will test this class in the next days and comment on this post with my result.

public class MySimpleStringProperty extends SimpleStringProperty {
    public MySimpleStringProperty(Object obj, String name) {
        super(obj, name);
    }

    public MySimpleStringProperty(Object obj, String name, String initVal) {
        super(obj, name, initVal);
    }

    @Override
    public void set(String arg0) {
        super.set(arg0);
        if (this.getBean() != null) {
            try {
                Field f = this.getBean().getClass().getDeclaredField(this.getName());
                f.setAccessible(true);
                f.set(this.getBean(), arg0);
            } catch (NoSuchFieldException e) {
                // logging here
            } catch (SecurityException e) {
                // logging here
            } catch (IllegalArgumentException e) {
                // logging here
            } catch (IllegalAccessException e) {
                // logging here
            }
        }
    }
}

Answer 1

Just figured out that there is provided the class JavaBeanStringProperty, which just fullfill my request.

Using this code I can directly bind the value of my bean to a StringProperty (included setting and getting of my value to / from my Bean).

binding = JavaBeanStringPropertyBuilder.create().beanClass(Model.class).bean(model).name("prop1").build();

The only problem I found is that when you change the value of the model after setting the binding, there is no update e.g. in the TextField.