GWT Editor Framework - Show ENUM using ValueListBox in own editor

Question

I have an Enum SupplierCode:

public enum SupplierCode
{       
    BG("British Gas"), CNG("Contract Natural Gas"), COR("Corona Energy");

    private String value;

    SupplierCode(String value)
    {
        if(value != "")
        {
            this.value = value;
        }
    }

    // ... toString() and fromString() omitted for brevity

    // for editor framework (?)
    public String getValue()
    {
        return value;
    }
    public void setValue(String value)
    {
        this.value = value;
    }
}

I display it in my editors using a ValueListBox:

@UiField(provided = true)
ValueListBox<SupplierCode> supplierCode = new ValueListBox<SupplierCode>(new AbstractRenderer<SupplierCode>()
{
    @Override
    public String render(SupplierCode object)
    {
        return object == null ? "" : object.toString();
    }
});

// in the constructor
public ContractEditor()
{
    initWidget(uiBinder.createAndBindUi(this));
    supplierCode.setAcceptableValues(Arrays.asList(SupplierCode.values()));
}

I have to edit this type a few times in my app so I wanted to make an editor for just this dropdown, called SupplierCodeEditor:

public class SupplierCodeEditor extends Composite implements Editor<SupplierCode>
{
    private static SupplierCodeEditorUiBinder uiBinder = GWT.create(SupplierCodeEditorUiBinder.class);

    interface SupplierCodeEditorUiBinder extends UiBinder<Widget, SupplierCodeEditor>
    {
    }

    @UiField(provided = true)
    ValueListBox<SupplierCode> value = new ValueListBox<SupplierCode>(new AbstractRenderer<SupplierCode>()
    {
        @Override
        public String render(SupplierCode object)
        {
            return object == null ? "" : object.toString();
        }
    });

    public SupplierCodeEditor()
    {
        initWidget(uiBinder.createAndBindUi(this));
        value.setAcceptableValues(Arrays.asList(SupplierCode.values()));
    }

}

However, when I use it, although it renders the list ok with the options, it doesn't select the actual value from the list. I thought having the getValue() and setValue() methods would work but seemingly not.

Does anyone know of a way to put this in one editor file? Then I won't have to repeat the code for the renderer and call setAcceptableValues() every place I want to use it.

Answer 1

Use LeafValueEditor<SupplierCode>:

public class SupplierEditor extends Composite implements LeafValueEditor<SupplierCode> {
    interface SupplierEditorUiBinder extends UiBinder<Widget, SupplierEditor> {
    }

    private static SupplierEditorUiBinder uiBinder = GWT.create(SupplierEditorUiBinder.class);

    @UiField(provided = true)
    ValueListBox<SupplierCode> codes;

    public SupplierEditor() {
        codes = new ValueListBox<>(new AbstractRenderer<SupplierCode>() {
            @Override
            public String render(SupplierCode object) {
                return object == null ? "" : object.toString();
            }
        });

        initWidget(uiBinder.createAndBindUi(this));

        codes.setAcceptableValues(Arrays.asList(SupplierCode.values()));
    }

    @Override
    public SupplierCode getValue() {
        return codes.getValue();
    }

    @Override
    public void setValue(SupplierCode value) {
        codes.setValue(value);
    }
}

This way, your widget will be easily pluggable in a Editor hierarchy. And you don't need the get/set methods in your SupplierCode enum.

Answer 2

You have to either:

• use @Editor.Path("") on your child ValueListBox

• make your SupplierCodeEditor implement LeafValueEditor<SupplierCode>, with delegating getValue and setValue to the ValueListBox

• make your SupplierCodeEditor implement IsEditor<LeafValueEditor<SupplierCode>, returning the ValueListBox's asEditor() from your own asEditor().

BTW, you absolutely don't need the getValue and setValue on your enum values.