h:commandButton inside h:dataTable [duplicate] - jsf

Question

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How can I pass selected row to commandLink inside dataTable or ui:repeat?
(4 answers)
Closed 7 years ago.
I am using a JSF data table. One of the columns in the table is a Command button.
When this button is clicked I need to pass few parameters (like a value of the selected row) using the Expression language. This paramaters need to be passed to the JSF managed bean which can execute methods on them.
I have used the following snippet of code but the value i am getting on the JSF bean is always null.
<h:column>
<f:facet name="header">
<h:outputText value="Follow"/>
</f:facet>
<h:commandButton id="FollwDoc" action="#{usermanager.followDoctor}" value="Follow" />
<h:inputHidden id="id1" value="#{doc.doctorid}" />
</h:column>
Bean Method:
public void followDoctor() {
FacesContext context = FacesContext.getCurrentInstance();
Map requestMap = context.getExternalContext().getRequestParameterMap();
String value = (String)requestMap.get("id1");
System.out.println("Doctor Added to patient List"+ value);
}
How can I pass values to the JSF managed bean with a commandbutton?

Answer 1

Use DataModel#getRowData() to obtain the current row in action method.
#ManagedBean
#ViewScoped
public class Usermanager {
private List<Doctor> doctors;
private DataModel<Doctor> doctorModel;
#PostConstruct
public void init() {
doctors = getItSomehow();
doctorModel = new ListDataModel<Doctor>(doctors);
}
public void followDoctor() {
Doctor selectedDoctor = doctorModel.getRowData();
// ...
}
// ...
}
Use it in the datatable instead.
<h:dataTable value="#{usermanager.doctorModel}" var="doc">
And get rid of that h:inputHidden next to the h:commandButton in the view.
An -less elegant- alternative is to use f:setPropertyActionListener.
public class Usermanager {
private Long doctorId;
public void followDoctor() {
Doctor selectedDoctor = getItSomehowBy(doctorId);
// ...
}
// ...
}
With the following button:
<h:commandButton action="#{usermanager.followDoctor}" value="Follow">
<f:setPropertyActionListener target="#{usermanager.doctorId}" value="#{doc.doctorId}" />
</h:commandButton>
Related:
The benefits and pitfalls of #ViewScoped - Contains CRUD example using DataModel<E>.