JSF访问Bean类中的html元素值

Question

I have a JSF application in which I have a combo box.

<h:selectOneMenu id="collectorType"
                           value="#{activityDataSource.object.type}"
                           rendered="#{empty activityDataSource.object.id}"
                           disabled="#{!sp:hasRight(facesContext, 'ManageApplication')}"
                           readonly="#{!sp:hasRight(facesContext, 'ManageApplication')}"
                           onchange="$('editForm:selectTypeButton').click();">
             <f:ajax event="change" 
                    execute="@this" 
                    render="dsTransformationRule dsCorrelationRule"
                    listener="#{activityDataSource.handleCollectorTypeChange}" />
            <f:selectItem itemValue="" itemLabel="#{msgs.select_collector_type}"/>
            <f:selectItems value="#{activityDataSource.collectorTypes}"/>
          </h:selectOneMenu>

And I am getting selected value of that combo box in bean class like:

public void setSelectedTransformationRule(String transformationRule)
        throws GeneralException {
    String collectorType = (String) getRequestParam().get("editForm:collectorType");
}

And I am successful in doing so. I am calling this method through ajax onchage event of combobox.

But if I try to get same combo box value in a different method i get null value.

public void handleCollectorTypeChange() throws GeneralException {
    String collectorType = (String) getRequestParam().get("editForm:collectorType");
}

Any help !

Answer 1

Because Process Events happens before Update Model Values you can retrieve the value from the component, from the UIViewRoot like this:

HtmlSelectOneMenu collectorTypeSelectMenu = (HtmlSelectOneMenu) FacesContext.getCurrentInstance().getViewRoot().findComponent("editForm:collectorType");
String collectorType = (String) collectorTypeSelectMenu.getValue();

Answer 2

try put the attributes process and partialSubmit in your ajax call with the values you need process like this:

<f:ajax event="change" 
   execute="@this" 
   render="dsTransformationRule dsCorrelationRule"
   process="@this, collectorType"
   partialSubmit="true"
   listener="#{activityDataSource.handleCollectorTypeChange}" />

In the process atrribute you can put all ids you need to process with the updated values (like you see in the screen.