JSF Ders32 - View Params

Çoğu kaynak bununla ilgili kafa karıştırıcı cümleler ve örnekler içerir. Konunun özeti şudur.

f:viewParams ile gelen request (istek) parametreleri yakalanır
h:link, h:button ile istek parametresi gönderilir.

Bu kadar basit. Çoğu site bu işi zorlaştırmak için midir bilinmez örnekleri karmaşıklaştırıyor, konuyu uzatıyor. İşin özü bu kadardır.

<f:metadata>
<f:viewParam name="..." value="..."/>
<f:viewParam name="..." value="..."/>
</f:metadata>

ViewParamları metadata içine yerleştirerek kullanır. ViewParamları kullanabilmek için ayrıca isim uzaylarına

xmlns:f="http://java.sun.com/jsf/core"

isim uzayını eklenir.

h:link ve h:button yardımıyla parametre gönderilmesi de aşağıdaki şekildedir.

<h:link outcome="sayfa?par1=a&par2=b" value="..."/>

<h:button outcome="sayfa?par1=a&par2=b" value="..."/>

Şimdi örnek programı paylaşalım.

diger.xhtml

<!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:h="http://xmlns.jcp.org/jsf/html"
 xmlns:f="http://java.sun.com/jsf/core">
<h:head>
 <title>diger.xhtml</title>
</h:head>
<h:body>
 <f:metadata>
  <f:viewParam name="ad" />
 </f:metadata>

 <h:outputText value="Direkt urlden giriş : #{ad}" />
 <br />

</h:body>
</html>

index.xhtml

<!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:h="http://xmlns.jcp.org/jsf/html"
 xmlns:ui="http://xmlns.jcp.org/jsf/facelets">
<h:head>
 <title>index.xhtml</title>
</h:head>
<h:body>

 <h:form>
  Ad<br />
  <h:inputText value="#{test.ad}" /><br /><br />
  <h:commandButton value="gonder" action="diger2?faces-redirect=true" />
 </h:form>

</h:body>
</html>

diger2.xhtml

<!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:h="http://xmlns.jcp.org/jsf/html"
 xmlns:f="http://java.sun.com/jsf/core">
<h:head>
 <title>diger2.xhtml</title>
</h:head>
<h:body>
 <f:metadata>
  <f:viewParam name="ad2" value="#{test.ad}" />
 </f:metadata>

 <h:outputText value="formdan giriş : #{test.ad}" />
 <br />


</h:body>
</html>

index2.xhtml

<!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:h="http://xmlns.jcp.org/jsf/html"
 xmlns:ui="http://xmlns.jcp.org/jsf/facelets">
<h:head>
 <title>index2.xhtml</title>
</h:head>
<h:body>

 <h:link outcome="diger3?faces-redirect=true;&amp;ad=enes"   value="diger3 sayfasına parametreyle git."/><br/><br/>
    <h:button outcome="diger4?faces-redirect=true;&amp;ad=enes" value="diger4 sayfasına parametreyle git."/>

</h:body>
</html>

diger3.xhtml

<!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:h="http://xmlns.jcp.org/jsf/html"
 xmlns:f="http://java.sun.com/jsf/core">
<h:head>
 <title>diger3.xhtml</title>
</h:head>
<h:body>
<f:metadata>
 <f:viewParam name="ad"/>
</f:metadata>

<h1>h:link</h1>
<h2>ad : #{ad}</h2>


</h:body>
</html>

diger4.xhtml

<!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:h="http://xmlns.jcp.org/jsf/html"
 xmlns:f="http://java.sun.com/jsf/core">
<h:head>
 <title>diger4.xhtml</title>
</h:head>
<h:body>
<f:metadata>
 <f:viewParam name="ad"/>
</f:metadata>

<h1>h:button</h1>
<h2>ad : #{ad}</h2>


</h:body>
</html>