How to send parameter to fileUploadListener in PrimeFaces fileUpload - file-upload

Question

When I create a model I would like to save images for a model. I am using PrimeFaces fileUpload component. When I save pictures I want to know to which model particular image refers to. That's why I need to send id of a model to backing bean.
Is there any possibility to send id of model to fileUploadListener?
<h:form enctype="multipart/form-data">
<p:panelGrid columns="2">
<h:outputLabel for="hotelName" value="#{msg.hotelName}"/>
<p:inputText value="#{apartmentNew.name}" id="hotelName"/>
<h:outputLabel for="hotelDescription" value="#{msg.hotelDescription}"/>
<p:inputText value="#{apartmentNew.description}" id="hotelDescription"/>
<h:outputLabel for="hotelImages" value="#{msg.hotelImages}"/>
<h:form enctype="multipart/form-data">
<p:fileUpload id="hotelImages"
fileUploadListener="#{apartments.handleImageUpload}"
mode="advanced"
sizeLimit="10000000"
allowTypes="/(\.|\/)(gif|jpe?g|png)$/">
</p:fileUpload>
</h:form>
</p:panelGrid>
<p:commandButton id="saveApartmentButton" value="#{msg.save}" action="save"/>
<p:commandButton id="cancelCreationApartmentButton" value="#{msg.cancel}"
action="cancel"/>
</h:form>

Answer 1

Not via request parameters. You can do so via component attributes.
E.g.
<p:fileUpload ...>
<f:attribute name="foo" value="bar" />
</p:fileUpload>
with
String foo = (String) event.getComponent().getAttributes().get("foo"); // bar

Answer 2

I needed to pass a key parameter along with the uploaded file. I found that fileUploadListener executes during the APPLY_REQUEST_VALUES phase, so I could not use an EL expression in the f:attribute tag. I also tried to find the value using event.getComponent().findComponent("id"), but although the component was present, the value was null. I think a #ViewScoped bean would fix the missing value, but I am stubbornly attempting to keep my beans at #RequestScoped until I have absolutely no other option. Ultimately, I had to use FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap().get("id") which I got from http://forum.primefaces.org/viewtopic.php?f=3&t=6432

Answer 3

Error in types:
String foo = event.getComponent().getAttributes().get("foo");
Instead, do it this way:
Object foo = event.getComponent().getAttributes().get("foo");
Integer foo = (Integer) event.getComponent().getAttributes().get("foo");

Answer 4

You can use:
<div onclick="#{myBean.myMethod(myParam)}" >
<p:fileUpload id="fileUpload" fileUploadListener="#{myBean.onFileUplod}" mode="advanced" dragDropSupport="true"
update=":messages" process="#this" >
</p:fileUpload>
</div>
Method in myBean:
public void myMethod(String myParam) {
selectedMyParam = myParam;
}
Then you can use selectedMyParam in onFileUpload method.