Question

is it possible sort primefaces datagrid data? as i’m aware it’s possible in data table.if it is not possible by default,is there any other way to do it? Thanks

Answer 1

Primefaces datagrid does not provide sorting nor filtering, and it seems that there are no plans for implementing it anytime soon.
I’ve implemented sorting in a datagrid using a p:selectOneMenu just above the datagrid with sorting options like “Date”, “Price (highest first)”, “Price (lowest first)”, etc. When the selected value changes, I use an ajax event to invoke a method that reloads the collection from database using the appropiate ORDER BY.

Example:

<h:form>
    <h:outputLabel value="Sort by: " />
    <p:selectOneMenu value="#{bean.selectedField}" >
        <f:selectItems value="#{bean.sortingFields}" />
        <p:ajax event="change" update="grid" />
    </p:selectOneMenu>

    <p:dataGrid id="grid" value="#{bean.collection}" var="item" >
            <!-- contents of datagrid here -->
    </p:dataGrid>
</h:form>

And in the managed bean:

private List<SelectItem> sortingFieds;
private String selectedField, currentSortField;
private boolean asc;
private List<YourEntity> collection;
@EJB private YourEJB yourEjb;

public void init() {
    // load sortingFields with list of fields to order by
    // set default value for currentSortField
    asc = true;
    collection = yourEjb.loadCollection(sortField, asc);
}

public void sortCollection() {
    if(currentSortField.equals(selectedField) {
        asc = !asc;
    } else {
        currentSortField = selectedField;
        asc = true;
    }
    collection = yourEjb.loadCollection(sortField, asc);
}

And in your ejb

public List<YourEntity> loadCollection(String sortfield, boolean asc) {
    String q = "SELECT e FROM YourEntity e ORDER BY " + sortfield + " ";
    if(asc) {
       q += "ASC";
     } else {
       q += "DESC";
    }
    Query query = entityManager.createQuery(q);
    return query.getResultList();
}