0.2.1 - Grid<MyBean> columns in design file

Recommended way to add columns to a vaadin-grid element is to add a custom attribute data-columns and then provide a space-separated list of property names, for example:

<vaadin-grid data-columns="property anotherProperty someOtherProperty"></vaadin-grid>

Those properties will be called with server-side Grid.addColumn(propertyName).