How to set a converter dynamically for a PrimeFaces component? - primefaces

Question

I am using p:autoComplete inside column of a data table. And I am setting
converter by using variable assigned to the data table converter="#{fieldVar.possibleValues}"
but, it throws :
converter="#{fieldVar.possibleValues}": java.lang.IllegalArgumentException: Cannot convert userConverter of type class java.lang.String to interface javax.faces.convert.Converter
possibleValues is a string
If this is not possible then how we can change the converter dynamically.
<p:dataTable var="fieldVar" value="#{dynamicReportBean.screenMetadataDTOs}" id="edit_meta_data_datatable">
<p:column headerText="Filter Names">
<h:outputText value="#{fieldVar.filedName}"/>
</p:column>
<p:column headerText="Filter Values">
<p:inputText value ="#{fieldVar.filedValue}"
placeholder="#{fieldVar.filedName}"
rendered="#{dynamicReportBean.canRenderFieldType(fieldVar.fieldId, 'TEXTFIELD')}" style="width: 220px">
</p:inputText>
<p:selectOneMenu value="#{fieldVar.filedValue}"
rendered="#{dynamicReportBean.canRenderFieldType(fieldVar.fieldId, 'DROPDOWN')}" style="width: 220px">
<f:selectItems value="#{dynamicReportBean.retrievePossibleDropDownValues(fieldVar.fieldId, fieldVar.fieldType, fieldVar.possibleValues)}"/>
</p:selectOneMenu>
<p:selectManyMenu value="#{fieldVar.filedValue}"
style="width: 220px"
showCheckbox="true"
rendered="#{dynamicReportBean.canRenderFieldType(fieldVar.fieldId, 'SELECT_MANY_CHECKBOX')}">
<f:selectItems value="#{dynamicReportBean.retrievePossibleDropDownValues(fieldVar.fieldId, fieldVar.fieldType, fieldVar.possibleValues)}"/>
</p:selectManyMenu>
<p:autoComplete value="#{fieldVar.filedValue}"
style="width: 220px"
placeholder="autocomplete"
completeMethod="#{dynamicReportBean.getAutoCompleteMethod}"
rendered="#{dynamicReportBean.canRenderFieldType(fieldVar.fieldId, 'AUTOCOMPLETE')}"
scrollHeight="300"
converter="#{fieldVar.possibleValues}"
size="25">
<f:attribute name="converterName" value="#{fieldVar.possibleValues}" />
<p:ajax event="itemSelect" listener="#{dynamicReportBean.onHandleSelect}"/>
</p:autoComplete>
</p:column>
</p:dataTable>
if I pass converter = "userConverter" It works fine but instead of that I want converter values come dynamically
public class UserConverter implements Converter {
#Override
public Object getAsObject(FacesContext context, UIComponent component,
String value) {
UserLOVBean lOVBean = null;
try {
UserService service = new UserServiceImpl();
UserFilterDTO filterDTO = new UserFilterDTO();
UserContext userContext
= (UserContext) context.getExternalContext().getSessionMap().
get("USER_CONTEXT");
filterDTO.setCmpCode(userContext.getCmpCode());
filterDTO.setOrgCode(userContext.getOrgCode());
if (value != null) {
filterDTO.setUserId(value);
}
for (UserLOVDTO lOVDTO : service.retrieveUserForAutoComplete(
filterDTO)) {
if (value.equals(lOVDTO.getUserId())) {
lOVBean = new UserLOVBean();
CopyUtil.copyValues(lOVDTO, lOVBean);
}
}
} catch (Exception ex) {
ex.printStackTrace();
Logger.getLogger(UserConverter.class.getName()).log(Level.SEVERE,
null, ex);
}
return lOVBean;
}
#Override
public String getAsString(FacesContext context, UIComponent component,
Object value) {
return String.valueOf(((UserLOVBean) value).getUserId());
}
}

Answer 1

Setting a converter for p:autoComplete (and any other PrimeFaces component) using the converter attribute is documented as:
An EL expression or a literal text that defines a converter for the component. When it's an EL expression, it's resolved to a converter instance. In case it's a static text, it must refer to a converter id.
So, if you want to use an EL expression, it must point to an instance of a converter. In your bean you could simply add:
public UserConverter getUserConverter() {
return new UserConverter();
}
And then, in your XHTML, use:
<p:anyComponent converter="#{myBean.userConverter}"/>