List box initialization through managed bean

[Akhilesh Trivedi]

Its like this, a bean with String array say "numbers".
I have a jsp with selectOneMenu tag. Further i have written code for initializing the numbers array as list-entry with values(1,2,3). I am not able to associate this array with my listbox (or selectOneMenu) tag, imean the tag and value. I have tried replacing selectOneMenu with dataTable with its value set as "bean.numbers" var="row" and outputting it in a column using outputText value="#{row}" (it works, that is list-entries value are being set).
Instead of dataTable i want to use selectOneMenu, how do I achieve the same?

[Franz van Betteraey]

Hi Akhilesh,

I would suggest better to generate a Map whose entries represent the labels and values of a SelectItem, eg.

private Map<String, String> numbers = new TreeMap<String, String>();

You can fill the list in your faces-config.xml (or by code):

<managed-bean>
<description>some bean</description>
<managed-bean-name>someBean</managed-bean-name>
<managed-bean-class>SomeBean</managed-bean-class>
<managed-bean-scope>session</managed-bean-scope>
<managed-property>
<description>predifined list of numbers</description>
<property-name>numbers</property-name>
<map-entries>
<key-class>java.lang.String</key-class>
<value-class>java.lang.String</value-class>
<map-entry>
<key>1</key>
<value>1</value>
</map-entry>
<map-entry>
<key>2</key>
<value>2</value>
</map-entry>
<map-entry>
<key>3</key>
<value>3</value>
</map-entry>
</map-entries>
</managed-property>
</managed-bean>


than include a method getNumbers in your bean code


public Map<String, String> getNumbers() {
return numbers;
}

and use the selectItems Tag to fill the selectOneMenu Component

<h:selectOneMenu value="#{bean.number}">
<f:selectItems value="#{bean.numbers}" />
</h:selectOneMenu></td>

(Also declare a bean property "number" to store the number to be post)

Hope this works.

Regards
Klaus

[Akhilesh Trivedi]

Thanks Klaus, i tried it. I dont know where I could initialize the Map. I just declared it and provided corresponding getters and setters.
when I run my JSP I get exception,

"javax.servlet.jsp.JspException: Conversion Error setting value ''{0}'' for ''{1}''. "

[Franz van Betteraey]

Maybe the Declaration of your Map (Generics?) does not fit to the configuration of your managed bean (<map-entries>/<key-class>/<value-class>).
It would be helpfull if you post some parts of your code (faces-config.xml, Bean and JSP).

Good Luck

[Akhilesh Trivedi]

Okay!

Here is portion of bean declation, (it is by name UserBean)

    
    
   private Map <String,String> numbers;
   String number;
   //following are getters and setters
   public void setNumber(String number) {
        this.number = number;
    }
 
    public String getNumber() {
        return number;
    }
 
    public void setNumbers(Map <String, String > numbers) {
        this.numbers = numbers;
    }
 
    public Map <String, String> getNumbers() {
        return numbers;
    }  

Following is the code in faces-config,

   
<property-name>numbers</property-name>
    <map-entries>
    <key-class>java.lang.String</key-class>
    <value-class>java.lang.String</value-class>
    <map-entry>
        <key>1</key>
        <value>1</value>
    </map-entry>
    <map-entry>
        <key>2</key>
        <value>2</value>
    </map-entry>
    <map-entry>
        <key>3</key>
        <value>3</value>
    </map-entry>       
    </map-entries>
</managed-property>
 

Code in JSP

   
 <h:selectOneMenu value="#{UserBean.number}">            
               <f:selectItem value="#{UserBean.numbers}"/>           
 </h:selectOneMenu>
            

[Akhilesh Trivedi]

For the face-config.xml I dont know if the code before property name would be interest to you, anyways, i snap it right from managed-bean tag itself...

 
<managed-bean>
<managed-bean-name>UserBean </managed-bean-name>
<managed-bean-class>
    com.jsfcompref.register.UserBean
</managed-bean-class>
<managed-bean-scope>session</managed-bean-scope>
<managed-property>
<property-name>firstName</property-name>
<value>Akhilesh</value>
</managed-property>
<managed-property>
<property-name>numbers</property-name>
    <map-entries>
    <key-class>java.lang.String</key-class>
    <value-class>java.lang.String</value-class>
    <map-entry>
        <key>1</key>
        <value>1</value>
    </map-entry>
    <map-entry>
        <key>2</key>
        <value>2</value>
    </map-entry>
    <map-entry>
        <key>3</key>
        <value>3</value>
    </map-entry>       
    </map-entries>
</managed-property>
</managed-bean>
   

[Franz van Betteraey]

it must be selectItems (with s at the end)

<h:selectOneMenu value="#{UserBean.number}">            
  <f:selectItems value="#{UserBean.numbers}"/>           
</h:selectOneMenu>

I'm always smiling. To look sad I have to perfom a headstand normally,.....

[Akhilesh Trivedi]

...and... and... and....... it worked! !! Thanks a lotttt Klaus. Not so important but still just one query, the list-box always gets filled up in a 3-2-1 fashion, irrespective of order map-entry tags in faces-config, any ideas why?
[ June 22, 2007: Message edited by: Akhilesh Trivedi ]

[Franz van Betteraey]

Use a sorted Map to influence the order.

private Map<String, String> numbers = new TreeMap<String, String>();

I do not know (better I do not believe) if the order of the map-entries in faces-config is secure.

Use other Types than String to sort numbers :-)

Have fun!