2

Using JSF 2.1.29

In list.xhtml

<p:commandLink id="ownerViewLinkId" value="#{petOwner.firstName} #{petOwner.lastName} " 
action="#{ownerAndPetListBean.viewPetOwnerFrmList(petOwner.id,petOwner.userId,0)}"
        onclick="PF('progrees_db').show()"
        oncomplete="PF('progrees_db').hide()"
        style="color:#0080FF;">
</p:commandLink>

In listBean (viewscoped),

public void viewPetOwnerFrmList(String ownerIdStr, String userIdStr,
            String petIdStr) {
    try {
        FacesContext.getCurrentInstance().getExternalContext().getFlash().put("ownerId",ownerIdStr);
            FacesContext.getCurrentInstance().getExternalContext().getFlash().put("userId",userIdStr);
            FacesContext.getCurrentInstance().getExternalContext().getFlash().put("petId",petIdStr);

            FacesContext.getCurrentInstance().getExternalContext()
                    .redirect("/ownerandpets/view");

    } catch (Exception e) {
            log.warn("FL Warning", e);
    }
}

pretty-config.xml

  <url-mapping id="ownerandpetsview"> 
      <pattern value="/ownerandpets/view" />          
      <view-id value="/WEB-INF/views/ownerAndPet/OwnerAndPetsView.xhtml" />
      <action onPostback="false">#{ownerAndPetViewBean.fillPage}</action> 
  </url-mapping>

In viewbean (viewscoped),

String petIdStr;
String userIdStr;
String ownerIdStr;
String firstName;
//include getters and setters
public void fillPage() {

    petIdStr = (String) FacesContext.getCurrentInstance().getExternalContext().getFlash().get("petId");
    userIdStr = (String) FacesContext.getCurrentInstance().getExternalContext().getFlash().get("userId");
    ownerIdStr = (String) FacesContext.getCurrentInstance().getExternalContext().getFlash().get("ownerId");

    System.out.println(ownerIdStr+" "+userIdStr+" "+petIdStr);
    firstName = getFromDBByOwnerId(ownerIdStr); 
}

In view page,

<h:outputText value="#{ownerAndPetViewBean.firstName}"/>

firstName is displayed after redirect. On refreshing the view page (by pressing f5), the string firstName becomes null and id strings printed in viewBean's fillPage is null. What i need is on refresh, i need to refetch firstName for which the ids must not be null. Had gone through this link Anyway to persist the flash data in request?

Tried the below but was not successful :

1.

FacesContext.getCurrentInstance().getExternalContext()
                    .redirect("/ownerandpets/view?faces-redirect=true");

2. 

FacesContext.getCurrentInstance()
    .getExternalContext().getFlash().keep("ownerId");
FacesContext.getCurrentInstance()
    .getExternalContext().getFlash().keep("userId");
FacesContext.getCurrentInstance()
    .getExternalContext().getFlash().keep("petId");

3. 

FacesContext.getCurrentInstance().getExternalContext()
    .getFlash().setKeepMessages(true);
FacesContext.getCurrentInstance().getExternalContext()
    .getFlash().setRedirect(true);

On Refresh debugging, the ids are there in the flash scope map on watching FacesContext.getCurrentInstance().getExternalContext().getFlash() , but the same is not displayed in watching FacesContext.getCurrentInstance().getExternalContext().getFlash().get("petId"); (see fig 2).

Values in Flash Map on Refresh - Fig 1 Fig 2

Update 1 (Answer):

As suggested by Xtreme Biker, added preRenderView to the view page.

<f:event type="preRenderView" listener="#{ownerAndPetViewBean.fillPage}"/> .

From the pretty-config.xml, remove or comment

<action onPostback="false">#{ownerAndPetViewBean.fillPage}</action>

Put a not postback checking in fillPage method and added flash.keep in managed bean. 

FacesContext.getCurrentInstance().getExternalContext().getFlash().keep("ownerId");

The above method will not work with pretty-faces action tag (if used instead of preRenderview) and we will get page with no values.

4

1 回答 1

1

prettyfaces 动作可能超出了当前 flash 状态的范围。不知道 pretty 动作的具体工作原理，但您需要flash.keep在执行重定向的同一请求周期中进行设置（如果使用 pretty，则由POST-REDIRECT-GET模式完成）。

无论如何，由于漂亮动作的文档示例显示了一个@RequestScopedbean，因此不知道它与 View Scope 和 flash 状态的兼容性。如果您仍在 JSF 2.1 中，我个人更喜欢使用f:event='preRenderView' 回发检查。如果是 JSF 2.2，请使用f:viewAction，而无需检查回发。

也可以看看：

于 2015-10-01T09:39:22.203 回答