Avoid creation of bean instance multiple times.

Question

Hi,
The Managed Bean/ Backing Bean is getting instantiated for each action. How do I avoid this?
I tried setting the scope of the bean to 'session' or 'application', in the faces_config.xml, but the result is the same.
Am I missing something here. Each time an action is performed the bean is getting instantiated.
For Ex:
I have two ListBoxes: selectManyListbox1 , selectManyListbox2.
and an OK button.
The functionality is to move the selectedItems of selectManyListbox1 to selectManyListbox2, when OK btn is clicked.
I have added valueChangeListener to selectManyListbox1, so that each time the checkbox inside selectManyListbox1 is selected I am capturing the value(selected Item) and assigning it to the global variable of the bean (say: String strSelectedValues - by default it's null). So in valueChangeListener method of the bean this string strSelectedValue is getting initialized with selected values from selectManyListbox1.
It's all fine till here.
Now when I click on Ok button, the correponding action method is called, here strSelectedValues is back to null. It means the bean is getting instantiated again.
How do I retain the value in strSelectedValues , so that I can move it to selectManyListbox2 on 'Ok' btn click.
Any help on this would be greatly appreciated.
Regards,

Answer 1

Hi,
I have cross checked the same. All declaration looks fine but it's not working.
This is the declaration in faces-config.xml:
<managed-bean>
<managed-bean-name>backingBeanScope.backing_TestList</managed-bean-name>
<managed-bean-class>com.hfm.view.backing.TestList</managed-bean-class>
<managed-bean-scope>session</managed-bean-scope>
</managed-bean>
</faces-config>
In jspx this is the code for ListBox1 and btn:
<af:selectManyListbox label="Label 1" autoSubmit="true" valuePassThru="true" valueChangeListener="#{backingBeanScope.backing_TestList.valueChangeListener}"
binding="#{backingBeanScope.backing_TestList.selectManyListbox1}"
id="selectManyListbox1">
<af:selectItem label="test1" value="test1"
binding="#{backingBeanScope.backing_TestList.selectItem1}"
id="selectItem1"/>
<af:selectItem label="test2" value="test2"
binding="#{backingBeanScope.backing_TestList.selectItem2}"
id="selectItem2"/>
<af:selectItem label="test3" value="test3"
binding="#{backingBeanScope.backing_TestList.selectItem3}"
id="selectItem3"/>
</af:selectManyListbox>
<af:commandButton text="Ok"
binding="#{backingBeanScope.backing_TestList.commandButton1}"
id="commandButton1"
action="#{backingBeanScope.backing_TestList.commandButton1_action}" />
In the backing bean:
private String strValue ; -Class level variable
public void valueChangeListener(ValueChangeEvent event) {
String colDefs = event.getNewValue().toString();
System.out.println("colDefs>>"+colDefs);
strValue = colDefs;
public String commandButton1_action() {
System.out.println("***********strValue*************"+strValue);
return null;
Here strValue is null.
Please let me know if I am missing something.
Regards,