4.7.4.2. Categorized Entities

If an entity implements com.haulmont.cuba.core.entity.Categorized interface, you can use com.haulmont.cuba.gui.components.RuntimePropertiesFrame component for displaying dynamic attributes of this entity. This component allows a user to select a category for the particular entity instance and specify values of dynamic attributes of this category.

In order to use the RuntimePropertiesFrame component in an edit screen, do the following:

  • Two datasources should be declared in the dsContext section:

    • runtimePropsDatasource - a specific datasource to load the CategoryAttributeValue instances. The mainDs attribute must refer to the main datasource, which contains the edited entity.

    • A regular collectionDatasource to load the list of categories of this entity type.

    Example:

    <dsContext>
  <datasource id="carDs"
      class="com.company.sample.entity.Car"
      view="carEdit"/>

  <runtimePropsDatasource id="runtimePropsDs"
      mainDs="carDs"/>

  <collectionDatasource id="categories"
      class="com.haulmont.cuba.core.entity.Category"
      view="_local">
    <query>
         select c from sys$Category c where c.entityType='sample$Car'
    </query>
  </collectionDatasource>
</dsContext>

  • Now, the runtimeProperties visual component may be included in the XML-descriptor of the screen:

    <runtimeProperties id="runtimePropsFrame"
  runtimeDs="runtimePropsDs"
  categoriesDs="categories"/>