How to get both label and value from f:selectItems

Question

I am working on a JSF page which has a dropdown based on List:

    <         


        

Answer 1

What if the the value should be Integer and label String and both are needed in backing bean. Using Map in bean doesn't work because JSF interprets the map key as label. Ideally it would be a LinkedHashMap and search the text by a number.

Seems upside down to search number (value) by a text (key). What if some implementation of JSF adds extra space to test or letter case changes for some reason. Then the value is not found from map.

Answer 2

You can't. That's just how HTML works. You know, JSF is a HTML code generator. The JSF <h:selectOneMenu> generates a HTML <select><option> . The HTML <select> element will only send the value attribute of the selected <option> element. It will not send its label.

But that shouldn't be a big issue. You namely already know both the value and label in the server side, inside the #{bean.availableItems}. All you need to do to get the associated label is to get it by the value as key. I suggest to make it a Map which in turn can also be used in f:selectItems.

Basic kickoff example:

public class Bean {
    private String selectedItem; // +getter +setter
    private Map<String, String> availableItems; // +getter

    public Bean() {
        availableItems = new LinkedHashMap<String, String>();
        availableItems.put("value1", "label1");
        availableItems.put("value2", "label2");
        availableItems.put("value3", "label3");
    }

    public void submit() {
        String selectedLabel = availableItems.get(selectedItem);
        // ...
    }
}

with

<h:selectOneMenu value="#{bean.selectedItem}">
    <f:selectItems value="#{bean.availableItems.entrySet()}" var="entry"
        itemValue="#{entry.key}" itemLabel="#{entry.value}" />
</h:selectOneMenu>

and in result

<p>Selected label is #{bean.availableItems[bean.selectedItem]}</p>

An alternative is to wrap both name and value in a javabean object representing an entity and set the whole object as value, via a converter.

See also:

• Our selectOneMenu wiki page
• How to populate options of h:selectOneMenu from database?

Answer 3

Instead of Using Map I tried like this and it's perfectly working for me to get both ItemValue and ItemLabel in the same property by using "ItemValue" attribute in selectItems tag.How ever provided no extra commas in the ItemLabel(@asfas....i had the same problem u mentioned so i selected this approach).

<h:selectOneMenu  value="#{company.issueDesc}"   required="true" onchange="submit()">
     <f:selectItem itemLabel="-- Select a Issue -- " itemValue="0"/>  
     <f:selectItems value="#{company.issueList}" var="model" itemLabel="#{model.IssueDesc}" itemValue="#{model.Code},#{model.IssueDesc}" >
      </f:selectItems>
</h:selectOneMenu>

Basically IssueDesc is String type in Bean Company

    public Class Company{

      private String issueDesc;    // getters and setters
      private int code;  // getters and setters
      private List<T>issueList; // getters and setters.


         public void getLblandVal(){

           String desc=getIssueDesc();
           String[] str_ary=desc.split(",");
           String s1=str_ary[0];
           String s2=str_ary[1];
          // parse **s1** to int;
    }


}

Answer 4

The following approach may also be useful in getting value and label using List <SelectItem>:
Here, facade, statesFacade fetches list of states from database/enterprise bean.

In view (xhtml page):

    <h:selectOneMenu id="statesSelectUi" value="#{applicationBean1.state}">
        <f:selectItems value="#{applicationBean1.stateSelectItems}"/>
        <f:ajax render="selectedItem" event="change" execute="statesSelectUi"/>
    </h:selectOneMenu>
    <br/>
    <br/>
    <h:outputText id="selectedItem" value="#{applicationBean1.selectedState}"/>

In the Managed Bean(applicationBean1.java):

private String state;

/**
     * @return the stateSelectItems
     */
    public List<SelectItem> getStateSelectItemsItems() {
        stateSelectItems.add(new SelectItem("-1","--- Select state ---"));
        int statesCount = statesFacade.count();
        List<StateSelectItems> states;
        states = statesFacade.findAll();
        for (int i = 0; i < statesCount; i++) {
            stateSelectItems.add(new SelectItem(states.get(i).getStateSlNo(), states.get(i).getStateName()));
        }
        return stateSelectItems;
    }


       public String getSelectedState(){
       if("".equals(getState()) || getState() ==null){
        return "";
       }else{
        return "Selected State : " + getStateSelectItems.get(Integer.parseInt(getState())).getValue()+", "++ getStateSelectItems.get(Integer.parseInt(getState())).getLabel();
       }
    }

Answer 5

This will do the trick.

private String getLabel(List<SelectItem> list, String selection) {
    String label = "";
    for (int i = 0; i < list.size(); i++) {
        if(selection.equals((String)list.get(i).getValue())) {
            label = (String)list.get(i).getLabel();
            break;
        }
    }

    return label;
}

In your example, you would pass in the availableItems as 'list' and selectedItem as 'selection'. This method will return the label value corresponding to the selectedItem.