Command components inside a p:carousel wrapped by a p:dataGrid using LazyDataModel<T> do not invoke action(Listener)s, when the bean is request scoped

Question

Example :

<p:dataGrid var="dRow" value="#{testBean}" lazy="true" rows="1" columns="1">
    <p:carousel var="cRow" value="#{dRow.subCategories}" headerText="#{dRow.catName}" itemStyle="width : 300px">
        <!--Show images but that part is excluded for brevity.-->
        <p:commandLink process="@this" value="#{cRow.subCatName}" actionListener="#{testBean.action(cRow)}"/>
    </p:carousel>
</p:dataGrid>

The managed bean :

@Named
@RequestScoped
public class TestBean extends LazyDataModel<Category> {

    @Inject
    private DataStore dataStore;
    private List<Category> categories;

    public TestBean() {}

    @PostConstruct
    private void init() {
        categories = dataStore.getCategories();
    }

    @Override
    public List<Category> load(int first, int pageSize, String sortField, SortOrder sortOrder, Map<String, Object> filters) {
        List<Category> list = dataStore.getCategories();
        setRowCount(list.size());
        return list;
    }

    public List<Category> getCategories() {
        return categories;
    }

    public void action(SubCategory subCategory) {
        System.out.println("action() invoked : " + subCategory.getSubCatName());
    }
}

The bean is decorated with @RequestScoped. DataStore is an application scoped bean where the List<Category> is created and stored.

The given command link does not trigger the action listener method (action()) in the managed bean unless either the bean is decorated with @ViewScoped (or wider) or the lazy data model is removed.

Thus, changing,

<p:dataGrid var="dRow" value="#{testBean}" .../>

to

<p:dataGrid var="dRow" value="#{testBean.categories}" .../>

will work i.e. the <p:commandLink> will invoke the action listener given (The lazy data model is excluded here. The given <p:dataGrid> is directly populated by a List<Category> from the backing bean).

Another alternative is to use a wider scoped bean like a view scoped bean as stated earlier.

Is it possible to use a request scoped bean along with a lazy data model in the given situation so that command components inside those components can work? I have many such view scoped beans just because of <p:commandLink>s inside a <p:carousel> wrapped by a <p:dataGrid> which could otherwise have simply been declared request scoped.

---

In case the application scoped bean where the list is maintained and the domain model classes are needed.

The application scoped bean :

@Named
@ApplicationScoped
public class DataStore {

    private List<Category> categories;

    public DataStore() {}

    @PostConstruct
    private void init() {
        categories = new ArrayList<>();

        Category category = new Category();
        category.setCatId(1L);
        category.setCatName("Animals");
        categories.add(category);

        List<SubCategory> subCategories = category.getSubCategories();

        SubCategory subCategory = new SubCategory();
        subCategory.setSubCatId(1L);
        subCategory.setSubCatName("Aquatic");
        subCategory.setCategory(category);
        subCategories.add(subCategory);

        subCategory = new SubCategory();
        subCategory.setSubCatId(2L);
        subCategory.setSubCatName("Aerial");
        subCategory.setCategory(category);
        subCategories.add(subCategory);

        subCategory = new SubCategory();
        subCategory.setSubCatId(3L);
        subCategory.setSubCatName("Mammals");
        subCategory.setCategory(category);
        subCategories.add(subCategory);
    }

    public List<Category> getCategories() {
        return categories;
    }
}

The domain class Category :

public class Category implements Serializable {

    private Long catId;
    private String catName;
    private List<SubCategory> subCategories = new ArrayList<>();
    private static final long serialVersionUID = 1L;

    public Category() {}

    public Long getCatId() {
        return catId;
    }

    public void setCatId(Long catId) {
        this.catId = catId;
    }

    public String getCatName() {
        return catName;
    }

    public void setCatName(String catName) {
        this.catName = catName;
    }

    public List<SubCategory> getSubCategories() {
        return subCategories;
    }

    public void setSubCategories(List<SubCategory> subCategories) {
        this.subCategories = subCategories;
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 47 * hash + Objects.hashCode(getCatId());
        return hash;
    }

    @Override
    public boolean equals(Object that) {
        if (!(that instanceof Category)) {
            return false;
        }

        return this == that || Objects.equals(getCatId(), ((Category) that).getCatId());
    }

    @Override
    public String toString() {
        return String.format("%s[catId=%d]", getClass().getCanonicalName(), getCatId());
    }
}

The domain class SubCategory :

public class SubCategory implements Serializable {

    private Long subCatId;
    private String subCatName;
    private Category category;
    private static final long serialVersionUID = 1L;

    public SubCategory() {}

    public Long getSubCatId() {
        return subCatId;
    }

    public void setSubCatId(Long subCatId) {
        this.subCatId = subCatId;
    }

    public String getSubCatName() {
        return subCatName;
    }

    public void setSubCatName(String subCatName) {
        this.subCatName = subCatName;
    }

    public Category getCategory() {
        return category;
    }

    public void setCategory(Category category) {
        this.category = category;
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 47 * hash + Objects.hashCode(getSubCatId());
        return hash;
    }

    @Override
    public boolean equals(Object that) {
        if (!(that instanceof SubCategory)) {
            return false;
        }

        return this == that || Objects.equals(getSubCatId(), ((SubCategory) that).getSubCatId());
    }

    @Override
    public String toString() {
        return String.format("%s[subCatId=%d]", getClass().getCanonicalName(), getSubCatId());
    }
}