'edit' object through datatable page

[trouby]

Hey,

I have a simple question regarding object editing,

I have a page containing a 'datatable' tag which fetches several objects via an EJB3,

I want two simple actions: delete per row/ edit per row,

by adding tag per row:

'<h:commandButton value="delete" action="#{myEjbBean.deleteObject}" />'

as it seems, the object gets injected into the bean fine (this is only working with h:commandButton tag, injection does not work when I use 's:link' tag.

so this process seems to be straight forward, but what about editing an object?

editing required two steps:
1) showing a form with the current object data (edit)
2) submitting the new edited data and persist it (update)

if the selected row object is already injected by seam, can I bypass the 'edit' action and re-direct to another page and have the selected object already accessible there? WITHOUT having an actionListener on the way? if so? how do I do that?

I tried the following:

<s:link view="/some_new_page.xhtml" value="edit">
<f:param name="id" value="#{myvar.id}"/>
</s:link>

but appearntly 'some_new_page.xhtml' does not have 'myvar' accessible, so I assume 's:link' tag does not inject the object...


Note (as I mentioned), when I Tried to use 's:link' tag with delete, the object was not injected as well,


Am I missing something? or I must use an actionListener method to inject the object for the 'edit' process and then use another method for the 'update' as well?

Thanks a lot,
Asaf

[gavin.king]

Way too vague:

What does "injected" mean? @DataModelSelection? Something else?

What scope is myEjbBean? What scope is the object that backs the edit page? etc...

Please show your actual code.

[trouby]

Eh, I'm sorry, here are some more details:

"injected" means 'DataModelSelection'

my 'DataModelSelection' object code (the intersting part)

@Scope(ScopeType.EVENT)
@Name("role")

@Table(name="ROLE")
@Entity
public class Role implements Serializable {
 private long roleId;
 private String name;
 private String description;

 public void setRoleId(long roleId) {
 this.roleId = roleId;
 }

 @Id
 @GeneratedValue(strategy = GenerationType.IDENTITY)
 @Column(name="ROLE_ID")
 public long getRoleId() {
 return roleId;
 }

 public void setName(String name) {
 this.name = name;
 }

 @Length(min=3, max=40) @NotNull //seam
 @Column(name="NAME", nullable=false)
 public String getName() {
 return name;
 }

 ....

}

My ejb3 used for actions:

@Stateless()
@Name("roleManager")
@Interceptors( {org.jboss.seam.ejb.SeamInterceptor.class} )
public class RoleBean implements RoleManagerLocal,RoleManagerRemote {

 //For insertions
 @In(create=true) @Valid
 Role role;

 @DataModel
 private List<Role> roleList;
 @DataModelSelection
 @Out(required=false)
 private Role selectedRole;

/**
 * Injected entity manager
 */
 //@PersistenceContext
 @PersistenceContext
 public EntityManager em;

....

here's the 'listRoles.xhtml' with the datatable of the DataModel (roleList) with the actions edit/delete I explained in the first post,

<t:dataTable id="rolesDataTableList"
 styleClass="scrollerTable"
 headerClass="standardTable_Header"
 footerClass="standardTable_Header"
 rowClasses="standardTable_Row1,standardTable_Row2"
 columnClasses="standardTable_Column,standardTable_ColumnCentered,standardTable_Column"
 var="role"
 value="#{roleList}"
 preserveDataModel="false"
 rows="10"
 >
 <h:column>
 <f:facet name="header">
 <h:outputText value="#{msgs.id}" />
 </f:facet>
 <h:outputText value="#{role.roleId}" />
 </h:column>

 <h:column>
 <f:facet name="header">
 <h:outputText value="#{msgs.name}" />
 </f:facet>
 <h:outputText value="#{role.name}" />
 </h:column>

 <h:column>
 <f:facet name="header">
 <h:outputText value="#{msgs.description}" />
 </f:facet>
 <h:outputText value="#{role.description}" />
 </h:column>
 <h:column>
 <f:facet name="header">
 <h:outputText value="#{msgs.actions}" />
 </f:facet>
 <f:facet name="header"><h:outputText value="#{msgs.actions}" /></f:facet>
 <h:outputLink value="roleEdit.seam">Edit
 <f:param name="roleId" value="#{role.roleId}"/>
 </h:outputLink>
 </h:column>
 </t:dataTable>

clicking on 'edit' link redirects to the page but 'role' seems to be empty.

Thanks a lot.

[gavin.king]

You still didn't show the code for roleEdit.

[trouby]

Hey again,

It is actually almost empty, I just added one input tag to see if the selected 'role' from last page is accessible...

<div class="entry">
 <div class="label"><h:outputLabel for="description">#{msgs.description}</h:outputLabel></div>
 <div class="input">
 <h:inputText id="description" value="#{role.description}" required="true"/><br/>
 <span class="errors"><h:message for="description" /></span>
 </div>
</div>

in order to see if it's injected into role entity...


the plan was add an action for the whole form which merge the updated entity...

Thanks.

[gavin.king]

Actually, your roleManager class looks broken, but its hard to say for sure.

It's a stateless component, hence the @DataModel scope defaults to EVENT, which means that the @DataModelSelection will always be null.

I have no idea what "@In(create=true) @Valid Role role" is for, but since you decided not to post all the code for that class, I can't tell if its right or wrong.

As a first step, you need to use @DataModel(scope=SESSION) to ensure that the @DataModelSelection will work.

In future, if I ask you to post code, please post _all_ of it, TIA.

[gavin.king]

"trouby" wrote:
It is actually almost empty, I just added one input tag to see if the selected 'role' from last page is accessible...

The Java code.

[trouby]

Hey again,

'@In(create=true) @Valid Role role' is irrelevant for this,
I have another page named 'roleAdd.xhtml' which its data is submitted to this entity, I hope it is valid...

I did post the code for that class... see above, it is the class with the @entity / @name("role"); annotations.

regarding the stateless context of 'roleManager', it must be stateful in order to keep the state of the 'DataModelSelection' entity?

I do not need the entity to be accessible for the whole session, just for the next page for editing...


Thanks a lot :)

[gavin.king]

Oh OK, I see what you've tried to do.

No, that will definitely not work. You never outject the value of the @DataModelSelection into the context variable named "role".

Seriously, you would be much better off taking a look at how the booking demo and the blog demo handle navigation from a list. They each use a different approach (booking demo uses @DataModelSelection, blog demo uses @RequestParameter). There are several variations upon both approaches.

[trouby]

yeah,
I see the problem...

Well, I looked at both examples,
blog example has two actions, delete/select, both use an action at the backend and make a usage of the 'DataModelSelection' object,
I couldnt find any example that links from a datatable selected row to another page without passing through an action... :(

Thanks a lot.

[trouby]

yeah,
I see the problem...

Well, I looked at both examples,
I couldnt find any example that links from a datatable selected row to another page without passing through an action... :-/

Thanks a lot.

[gavin.king]

It is *totally* possible to do this in pull-MVC style, without using an action.

Perhaps the easiest way for you us to use an @Factory method.

[gavin.king]

ie. an @Factory method that outjects the Role, after either getting its id from a request parameter, or calling back to the other component to get the @DataModelSelection.

[trouby]

Cool,

that what I'm looking for, it's really a waste of an action / navigation-rule for raising an 'edit' form for the selected @DataObjectSelection entity,

Are there any examples for this? it'll be nice to see a simple CRUD app,


I appriciate your help.

[trouby]

Hey,

back to this, if someone is interested, I found two options (as directed by Gavin)

1) using factory method for outjecting the selected entity, but since I already have too much factory methods I passed away
2) outjecting the selected object by handling the ID of the selected object as a parameter:

1) in the datatable list, add an '<f:param> tag, specifying the ID of the entity"
2) add under META-INF/pages.xml file the view-id of the page related for editing/handling the selected entity with an action on a bean to outject the selected entity by using '@RequestParameter("paramName')

The 'blog' sample works with an MVC style and makes a usage of pages.xml and parameters, so you can take a look at it.


Cheers.