Seam's tips for Seam in Action (1)

1) add entity by method-binding
page 18

#{tipAction.add(tip)}


    public void add(GolfTip tip) {
        entityManager.persist(tip);
        activeTip = tip;
        facesMessages.add(
                "Thanks for the tip, #{activeTip.author}!");
        retrieveAllTips();

    }

2) factory component trace
seam's factory component

which did not show in the log,

using following to record the in the log

log.info("Factory for tips called. Retrieving all golf tips...");

3) check empty content

if (tip.getContent().trim().length() == 0) { FacesMessages.instance().add("Please provide a tip from which we may all learn.");
return;
}

4) remove component
Contexts.removeFromAllContexts("tip");
// another option is to outject a null value to the context variable tip

5) find entity / remove entity

activeTip = entityManager.find(GolfTip.class, activeTip.getId());
entityManager.remove(activeTip);


6) display error

<div class="prop">
<h:outputLabel styleClass="name" for="author">Author <span class="required">*</span></h:outputLabel>
<span class="value">
<h:inputText id="author" value="#{tip.author}" required="true" style="width: 150px;"/>
</span>
<span class="error">
<h:graphicImage value="/img/error.gif" rendered="#{not empty facesMessages.getCurrentMessagesForControl('author')}" styleClass="errors"/>
<h:message for="author" styleClass="errors"/>
</span>
</div>

7) set order of entityquery
pg 68
public String getOrder() {
if (super.getOrder() == null) {
setOrder("name asc");
}
return super.getOrder();
}