Question

Does anybody have a solution to why I would be saving nulls to a OneToMany List on a server entity through a GXT Grid that contains a ListStoreEditor sub-editor?

I’ve followed the Sencha Example, GridBindingExample to a tee.
http://www.sencha.com/examples/#ExamplePlace:gridbinding

public class MyEditor implements IsWidget, Editor<FooProxy> {
    interface Binder extends UiBinder<Widget, MyEditor> {}
    private static Binder uiBinder = GWT.create(Binder.class);

    public interface Driver extends SimpleBeanEditorDriver<MyProxy, MyEditor> {}    
    private Driver driver = GWT.create(Driver.class);

    private ListStore<BarProxy> store;
    ListStoreEditor<BarProxy> items;

    @Ignore
    @UiField(provided = true)
    Grid<BarProxy> grid;

    @Ignore
    @UiField
    ChildEditor childEditor;

    @Override
    public Widget asWidget() {
        MyProperties props = GWT.create(MyProperties.class);
        this.store = new ListStore<BarProxy>(props.key());

        List<ColumnConfig<BarProxy, ?>> columns = new ArrayList<ColumnConfig<BarProxy, ?>>();
        columns.add(new ColumnConfig<BarProxy, String>(props.itemName(), 300, "MyColumn"));

        this.grid = new Grid<BarProxy>(store,new ColumnModel<BarProxy>(columns));
        items = new ListStoreEditor<BarProxy>(store);

        Widget widget = uiBinder.createAndBindUi(this);
        driver.initialize(childEditor);

        childEditor.getCreateButton().addSelectHandler(new SelectHandler() {
            @Override
            public void onSelect(SelectEvent event) {
                RequestContext context = factoryProvider.get().barRequest();
                BarProxy entity = context.create(BarProxy.class);

                entity.setName("Eugene Qtest");
                entity.setAge(45);

                driver.edit(entity);
                store.add(driver.flush());  
            }       
        });

        return widget;  
    }
}

public class ChildEditor implements IsWidget, Editor<BarProxy> {
    interface Binder extends UiBinder<Widget, ChildEditor> {}
    private static Binder uiBinder = GWT.create(Binder.class);

    @UiField
    TextButton createButton;

    @Override
    public Widget asWidget() {
        return uiBinder.createAndBindUi(this);
    }

    public TextButton getCreateButton() {
        return createButton;
    }
}

On an upper level presenter in my code, I am calling:

RequestContext req = editorPresenter.getDriver().flush();
req.fire();

This does save all data elements that the GWT Editor captures. In my database it does create the row for the grid in the above code, but all the values are null, so when the RequestContext fires, the persist brings back an empty row within the grid. So there is no foreign key to associate the entity in the OneToMany relationship back to its parent entity.

Also, I’ve looked at the JSON request and response to the server and it doesn’t look like any of the values are being sent in the entity. It may be obfuscated, but it looks as though the other values are in plain text, so I don’t think the proxy entity values are even being passed.

Any help would be great! Thanks

Answer 1

This took me days to figure out, with the help of Colin in the above comments, Thanks!

The reason the grid was populating, but when you flushed the main editor on save, the values disappeared and a blank row was inserted into the grid, was because you have to implement the HasRequestContext interface on the editor to maintain the same RequestContext session. Below is my amended code.

public class MyEditor implements IsWidget, Editor<FooProxy>, HasRequestContext<FooProxy> {
    interface Binder extends UiBinder<Widget, MyEditor> {}
    private static Binder uiBinder = GWT.create(Binder.class);

    private RequestContext ctx;    

    private ListStore<BarProxy> store;
    ListStoreEditor<BarProxy> items;

    @Ignore
    @UiField(provided = true)
    Grid<BarProxy> grid;

    @Ignore
    @UiField
    ChildEditor childEditor;

    @Override
    public Widget asWidget() {
        MyProperties props = GWT.create(MyProperties.class);
        this.store = new ListStore<BarProxy>(props.key());

        List<ColumnConfig<BarProxy, ?>> columns = new ArrayList<ColumnConfig<BarProxy, ?>>();
        columns.add(new ColumnConfig<BarProxy, String>(props.itemName(), 300, "MyColumn"));

        this.grid = new Grid<BarProxy>(store,new ColumnModel<BarProxy>(columns));
        items = new ListStoreEditor<BarProxy>(store);

        Widget widget = uiBinder.createAndBindUi(this);
        driver.initialize(childEditor);

        childEditor.getCreateButton().addSelectHandler(new SelectHandler() {
            @Override
            public void onSelect(SelectEvent event) {
                RequestContext context = ctx.barRequest();
                BarProxy entity = context.create(BarProxy.class);

                entity.setName("Eugene Qtest");
                entity.setAge(45);

                ctx.edit(entity);
                store.add(entity);  
            }       
        });

        return widget;  
    }

    @Override
    public void setRequestContext(RequestContext ctx) {
        this.ctx = ctx;     
    }
}