Create a widget for selecting columns

    public final Property<List<String>> selectColumnIds = newStringList("selectColumnIds"); //this would hold the selected columns ids

    public void setupProperties() {
        super.setupProperties();
        //setup  possible values
        selectColumnIds.setPossibleValues(new NamedThing[]{
            new NamedThing("col1","Surname"),
            new NamedThing("col2","Name"),
            new NamedThing("col3","Phone"));
        //may setup default selected column like this
        selectColumnIds.setValue(selectColumnIds.getPossbileValues().get(0));
    }
    public void setupLayout() {
        super.setupLayout();
        Form mainForm = new Form(this, Form.MAIN);
        Widget tableSelectionWidget = widget(selectColumnIds).setWidgetType(MULTIPLE_VALUE_SELECTOR_WIDGET_TYPE);
        mainForm.addRow(tableSelectionWidget);
    }

{
  "jsonSchema": {
    "title": "Main form",
    "type": "object",
    "properties": {
      "selectColumnIds": {
          "type": "array",
          "items": {
              "type": "string",
              "enum": ["col1", "col2", "col3"],
              "enumNames": ["Surname","Name","Phone" ]
          },
          "uniqueItems": true
      },
    }
  },
  "uiSchema": {
    "selectColumnIds": {
      "ui:widget":"listview"
    }
  },
  "properties": {
      "selectColumnIds":["col1"]
  }
}