DataTable: when it is updated, the filter values are set empty. (LazyDataModel + "special" API-usage)

As in the example below, after selecting a value from the selectcheckbox menu, the filter values are lost when the table is updated. It works fine with version 11.

<h:form>
      <p:dataTable var="customer" value="#{dtLazyView.lazyModel}" paginator="true" rows="10"
                   paginatorTemplate="{RowsPerPageDropdown} {FirstPageLink} {PreviousPageLink} {CurrentPageReport} {NextPageLink} {LastPageLink}"
                   rowsPerPageTemplate="5,10,15" selectionMode="single"
                   selection="#{dtLazyView.selectedCustomer}"
                   id="customerTable" widgetVar="_customerTable">

        <p:column headerText="Name" sortBy="#{customer.name}">
          <h:outputText value="#{customer.name}"/>
        </p:column>
        <!-- This filter hides correctly, but is not working when updated -->
        <p:column headerText="country " sortBy="#{customer.country}" filterBy="#{customer.country.name}">
          <f:facet name="filter">
            <p:selectCheckboxMenu id="multiple" value="#{dtFilterView.selectCountries}" style="min-width: 15rem"
                                  multiple="true" scrollHeight="250" updateLabel="true">
              <p:ajax event="change" process="@this" update="@form:customerTable"/>
              <f:selectItems value="#{dtLazyView.countries}"/>
            </p:selectCheckboxMenu>
          </f:facet>
          <h:outputText value="#{customer.country.name}"/>
        </p:column>
      </p:dataTable>

    </h:form>

[christophs78]

Even better - provide a (probably failing) integration test. Use https://github.com/primefaces/primefaces/commit/e7333816c420b260c504f8bc9238ae7059902521 as kind of template. (This way we ensure not to break existing usecases. PrimeFaces, JSF and DataTable allow for so many usecases. Integration tests help us to avoid breaking other existing usecases while trying to fix or enhance other ones.)

[djmj]

Yes that is correct.

Simplified example

Here simple test files i send @mertsincan at PRO support. In this test intentional i show the filterYear property again in the header facet and also use a second component outside the table to double check.

This shows, that the filterYear is correctly pushed to the bean but on update the input component in the filter facet is not updated with that value.

<p:column filterBy="#{car.year}" sortBy="#{car.year}">
	<f:facet name="header">
		<!-- check if filterYear is correctly pushed to bean on change -->
		<h:outputText value="Year: #{testDataTableFilterAjaxBean.filterYear}" />
	</f:facet>
				
	<f:facet name="filter">
		<!-- 1. push filterYear to bean
			2. update table
			3. selectOneMenu looses value and shows 'NONE' but in facet header we see its set -->						
		<p:selectOneMenu id="filterYear" value="#{testDataTableFilterAjaxBean.filterYear}" size="4" > 
			<f:selectItem itemLabel="None" itemValue="#{null}" />
			<f:selectItems value="#{testDataTableFilterAjaxBean.years}" />		
			<p:ajax process="@this" update="@form"/>							
		</p:selectOneMenu>
	</f:facet>
				
	<h:outputText value="#{car.year}" />
</p:column>

test-dataTableFilter-ajax-lost.zip