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I have a JSF facelets page that displays a table of data depending on which page they are viewing. When I display page 1, I call the view() action method to get the data from the database for both pages and store it as a private member field of the bean (two arrays). I also call conversation.start() on the injected conversation instance in the view() method.
When the user clicks the "next" button (h:commandButton) to go to page 2, I am executing a next() method to update the backing bean to point to array 2 so it will print out its contents. The problem is, array 2 no longer exists. I don't know why I am losing conversation scope. Any ideas?
//tells the object which page we are on, and thus what data to display. private int part = 1; // These arrays are filled with data but conversation scope doesn't // keep them on the next postback. private int[] part1 = new int[15], part2 = new int[15]; 
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You should paste some more code so we can help you better. From what you say i cannot see where you called the method for ending the conversation(You need that too when working with conversation scope).
I will paste here a little example that i think will help you understand how conversation scope works:
This is the start page of a wizard(Conversation scope is great for wizards)
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:ui="http://java.sun.com/jsf/facelets" xmlns:h="http://java.sun.com/jsf/html" xmlns:f="http://java.sun.com/jsf/core"> <h:head> <title>ConversationScoped demo CDI(Component Dependency Injection)</title> </h:head> <h:body> <h3>ConversationScoped demo CDI(Component Dependency Injection)</h3> <p>A conversation scope provides persistence until a goal is reached<br /> In this example the first entered value will remain until the end method is called<br /> in some page.<br /> This is a really useful gadget, for making registration wizards and similar tools...</p> <h:form> <h:outputText value="Type something" /> <h:inputText value="#{ supportBB.someValue}" /> <h:commandButton value="continue" action="#{ supportBB.onClick}" /> </h:form> </h:body> </html> This is the second page of the wizard
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xmlns:ui="http://java.sun.com/jsf/facelets" xmlns:h="http://java.sun.com/jsf/html" xmlns:f="http://java.sun.com/jsf/core"> <h:head> <title>ConversationScoped demo CDI(Component Dependency Injection)</title> </h:head> <h:body> <h3>This is the next page(The value is saved in the conversation)</h3> <h4><h:outputText value="#{ supportBB.someValue}"/></h4> <h:form> <h:commandButton value="Finish conversation" action="#{ supportBB.onKeepGoing}"/> </h:form> </h:body> </html> And this is the page where the scope ends
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xmlns:ui="http://java.sun.com/jsf/facelets" xmlns:h="http://java.sun.com/jsf/html" xmlns:f="http://java.sun.com/jsf/core"> <h:head> <title>ConversationScoped demo CDI(Component Dependency Injection)</title> </h:head> <h:body> <h3>This is the last page.The value still saved in conversation(until the end() method is called)</h3> <h4><h:outputText value="#{ supportBB.someValue}" /></h4> <h:form> <h:outputText value="Click finish to end the conversation(So saved values are disposed)" /> <h:commandButton value="Finish" action="#{ supportBB.onFinish}" /> </h:form> </h:body> </html> Here the @ConversationScoped backing bean that starts and ends the conversation
package backingbeans; import java.io.Serializable; import javax.enterprise.context.Conversation; import javax.enterprise.context.ConversationScoped; import javax.inject.Inject; import javax.inject.Named; @Named() @ConversationScoped() public class SupportBB implements Serializable { private static final long serialVersionUID = 1L; private String someValue; @Inject private Conversation conversation; // Control start and end of conversation public void start() { conversation.begin(); } public void end() { conversation.end(); } // Navigation public String onClick() { if(someValue.equals("") || conversation == null) { return "";//Dont go anywhere if the there was no input the field } start(); return "nextpage?faces-redirect=true"; } public String onKeepGoing() { return "finish?faces-redirect=true"; } public String onFinish() { end();// If triggered when there is no conversation(i.e URL Navigation) // there will be an exception return "index?faces-redirect=true"; } // Getters & Setters public String getSomeValue() { return someValue; } public void setSomeValue(String someValue) { this.someValue = someValue; } } I think this example is very simple and can help you understand how it works. Ask if you don't understand something
NOTE:
I think but i am not sure at 100% but ConversationScope only works if the backing bean is a CDI bean. This mean uses the annotation @Named. Better double check that.
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