How to update the table value in the valuechange event?

Question

I have an input field in the datatable with the valueChangeListener
<rich:dataTable id="cart" value="#{cart.cartList}" var="item">
<h:inputText value="#{item.cost}" id="qty" valueChangeListener="#{items.updateCost}" onchange="submit()">
<h:outputText value="#{item.errorMsg}"> </h:outputText>
in the backing bean
     Item item = (Item) model.getRowData();
// do some update, if the cost too larger, change to max_cost
     item.setCost(max_cost);
     item.setErrorMsg("Error Msg");
After calling the valuechange method, the screen output doesn't update the cost.
How to update the table value in the valuechange event?

Answer 1

As you're misusing the valueChangeListener to set another input field, you need to skip the update model values phase. Otherwise the value set in the valueChangeListener will be overridden by the submitted value. You can do this by calling the FacesContext#renderResponse() inside the valueChangeListener method. This will shift the current phase immediately to the render response phase, hereby skipping the update model values and invoke application phases.