jsf - 传入参数的问题ViewScoped bean 的

Question

我有一个 ViewScoped jsf 页面，其中列出了一组基于 accountId 的事务。当用户导航到页面时，accountId 会在 URL 中传递，例如 transactions_byaccount?accountId=3。这会在 @PostConstruct 循环中为提供的 accountId(bound to #{param.accountId}) 加载交易，并使用 .

在列出的每个事务上，用户还可以通过选择一个下拉菜单并单击一个按钮来更改事务的类别，该按钮调用一个在 EL 方法表达式中传递事务的操作。除了以下情况外，这按预期工作。

进入页面后，还可以使用下拉列表，其中包含其他帐户的列表，下拉值绑定到 accountId。当用户单击重新加载按钮时，将调用该操作以获取与新选择的帐户关联的交易。交易按预期列出。但是，当用户现在为事务选择一个新类别并单击按钮以更新事务时，EL 方法表达式将使用用户用于导航到页面的第一个事务列表中的事务调用该操作。

有人提到如果列表值更改不兼容可能会发生这种情况，但我的getter方法目前是一个非常简单的方法。

非常感激任何的帮助。

jsf在方法表达式中传递参数在ViewScoped bean中失败

完整代码如下

我的 bean 包 applogic.transactions；

import java.sql.Connection;
import java.util.ArrayList;
import java.util.List;

import javax.faces.bean.ManagedBean;
import javax.faces.bean.ManagedProperty;
import javax.faces.bean.RequestScoped;
import javax.faces.bean.ViewScoped;
import javax.faces.context.FacesContext;
import javax.faces.model.SelectItem;

import applogic.Conns;

import finance.bean.TransactionsListBean;
import finance.dao.AccountsDAO;
import finance.dao.TransactionsDAO;
import finance.daobase.BusinessDAO;
import finance.model.Accounts;
import finance.model.Transactions;
import java.io.Serializable;
import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;

@ManagedBean(name = "transactions_byaccount")
@ViewScoped
public class Transactions_Byaccount extends TransactionsListBean implements Serializable {
    List<Transactions> resultList;

    boolean initialized;

    @ManagedProperty("#{param.accountId}")
    private int accountId;

    public SelectItem[] accountsSelections;

    @ManagedProperty("#{param.sortOrder}")
    private int sortOrder;

    public SelectItem[] sortOrderSelections;

    @ManagedProperty("#{param.orderColumn}")
    private int orderColumn;

    public SelectItem[] orderColumnSelections;

    public Transactions_Byaccount() {

    }

    public String updateCategories(String redirectURL) {
        String result = redirectURL;

        Connection cons = Conns.getConFinanceDB();
        for( Transactions temp : (List<Transactions>)this.getPageList() )
            TransactionsDAO.Update(cons, temp);

        resultList = null;

        if( redirectURL != null && redirectURL.length() == 0 )
            redirectURL = null;

        return redirectURL;
    }

    public String updateCategory(String redirectURL, Transactions arg) {
        String result = redirectURL;

        Connection cons = Conns.getConFinanceDB();
        TransactionsDAO.Update(cons, arg);

        resultList = null;

        if( redirectURL != null && redirectURL.length() == 0 )
            redirectURL = null;

        return result;
    }

    @PostConstruct
    public void init() {
        //if (FacesContext.getCurrentInstance().) {
            if(resultList == null || initialized == false) {
                 Connection cons = Conns.getConFinanceDB();
                 List<Accounts> accountsList = AccountsDAO.List(cons);
                 List<SelectItem> listOfAccountsSelectItems = new
                 ArrayList<SelectItem>();

                 for( Accounts temp : accountsList ) {
                     listOfAccountsSelectItems.add(new SelectItem(temp.getId(), temp.getTitle()));
                 }

                 accountsSelections = listOfAccountsSelectItems.toArray(new SelectItem[listOfAccountsSelectItems.size()]);

                 List<SelectItem> sortOrderList = new ArrayList<SelectItem>();
                 sortOrderList.add(new SelectItem(1, "Asc"));
                 sortOrderList.add(new SelectItem(2, "Desc"));       
                 sortOrderSelections = sortOrderList.toArray(new SelectItem[sortOrderList.size()]);

                 List<SelectItem> orderColumnList = new ArrayList<SelectItem>();
                 orderColumnList.add(new SelectItem(1, "Transaction Date"));
                 orderColumnList.add(new SelectItem(2, "Action Date"));      
                 orderColumnList.add(new SelectItem(3, "Reconciled Date"));
                 orderColumnSelections = orderColumnList.toArray(new SelectItem[orderColumnList.size()]);       

                resultList = TransactionsDAO.ListByaccount(cons, accountId, getCurrentPageNo(), getPageSize(), orderColumn, sortOrder);
                initialized = true;
            }
        // }

    }

    public void reload() {
        Connection con = Conns.getConFinanceDB();
        resultList = TransactionsDAO.ListByaccount(con, accountId, getCurrentPageNo(), getPageSize(), orderColumn, sortOrder);
        initialized = true;

    }

    public String reload(String returnUrl) {
        Connection con = Conns.getConFinanceDB();
        resultList = TransactionsDAO.ListByaccount(con, accountId, getCurrentPageNo(), getPageSize(), orderColumn, sortOrder);
        initialized = true;     
        return returnUrl;
    }

    public Object getPageList() {
        return resultList;
    }

    public int getMaxCount() {
        Connection con = Conns.getConFinanceDB();
        int result = TransactionsDAO.CountByaccount(con, accountId);
        return result;
    }

    public int getAccountId() {
        return accountId;
    }

    public void setAccountId(int accountId) {
        this.accountId = accountId;
    }

    public SelectItem[] getAccountsSelections() {
        return accountsSelections;
    }

    public void setAccountsSelections(SelectItem[] accountsSelections) {
        this.accountsSelections = accountsSelections;
    }

    public int getSortOrder() {
        return sortOrder;
    }

    public void setSortOrder(int sortOrder) {
        this.sortOrder = sortOrder;
    }

    public SelectItem[] getSortOrderSelections() {
        return sortOrderSelections;
    }

    public void setSortOrderSelections(SelectItem[] sortOrderSelections) {
        this.sortOrderSelections = sortOrderSelections;
    }

    public int getOrderColumn() {
        return orderColumn;
    }

    public void setOrderColumn(int orderColumn) {
        this.orderColumn = orderColumn;
    }

    public SelectItem[] getOrderColumnSelections() {
        return orderColumnSelections;
    }

    public void setOrderColumnSelections(SelectItem[] orderColumnSelections) {
        this.orderColumnSelections = orderColumnSelections;
    }   

    public boolean isInitialized() {
        return initialized;
    }

    public void setInitialized(boolean initialized) {
        this.initialized = initialized;
    }

    public List<Transactions> getResultList() {
        return resultList;
    }

    public void setResultList(List<Transactions> resultList) {
        this.resultList = resultList;
    }
}

现在我的页面

<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:t="http://myfaces.apache.org/tomahawk"
    xmlns:f="http://java.sun.com/jsf/core" xml:lang="en" lang="en">


<ui:composition template="/WEB-INF/templates/template_main.xhtml">
    <ui:param name="title" value="transactions"></ui:param>
    <f:metadata>
        <f:viewParam name="pageNo" value="#{transactions_byaccount.pageNo}"/>
        <f:viewParam name="accountId" value="#{transactions_byaccount.accountId}"/>
        <f:viewParam name="sortOrder" value="#{transactions_byaccount.sortOrder}"/>
        <f:viewParam name="orderColumn" value="#{transactions_byaccount.orderColumn}"/>
        <f:event type="preRenderView" listener="#{transactions_byaccount.init}" />
    </f:metadata>
    <ui:define name="operationalbar">
        <div>
            <span >
                <h:selectOneMenu value="#{transactions_byaccount.accountId}" >
                    <f:selectItems value="#{transactions_byaccount.accountsSelections}"/>
                </h:selectOneMenu>
            </span>
            <span >
                <h:commandLink action="#{transactions_byaccount.reload('')}">
                    <h:outputText value="Reload"></h:outputText>
                    <f:param name="pageNo" value="1" />
                    <f:param name="accountId" value="#{transactions_byaccount.accountId}" />
                    <f:param name="sortOrder" value="#{transactions_byaccount.sortOrder}" />
                    <f:param name="orderColumn" value="#{transactions_byaccount.orderColumn}" />
                </h:commandLink>
            </span>         
            <span>
                <h:link outcome="transactions_byaccount_header">
                    <h:outputText value="Back to accounts list"></h:outputText>
                </h:link>
            </span>         
            <span>
                <h:commandLink action="#{transactions_byaccount.updateCategories('')}">
                    <h:outputText value="Update Categories"></h:outputText>
                    <f:param name="pageNo" value="#{param.pageNo}" />
                    <f:param name="accountId" value="#{param.accountId}" />
                    <f:param name="sortOrder" value="#{param.sortOrder}" />
                    <f:param name="orderColumn" value="#{param.orderColumn}" />
                </h:commandLink>        
            </span>
            <div></div> 
        </div>
    </ui:define>

    <ui:define name="pagingbar">
        <div>
            <span>
                <h:commandLink title="Go to page first page"  >
                    <h:outputText value="first"></h:outputText>
                        <f:param name="pageNo" value="#{transactions_byaccount.firstPage}" />
                        <f:param name="accountId" value="#{param.accountId}" />
                        <f:param name="sortOrder" value="#{param.sortOrder}" />
                        <f:param name="orderColumn" value="#{param.orderColumn}" />             
                </h:commandLink>
            </span>
            <span>
                <h:commandLink title="Go to page prev page">
                    <h:outputText value="prev"></h:outputText>
                        <f:param name="pageNo" value="#{transactions_byaccount.prevPage}" />
                        <f:param name="accountId" value="#{param.accountId}" />
                        <f:param name="sortOrder" value="#{param.sortOrder}" />
                        <f:param name="orderColumn" value="#{param.orderColumn}" />
                </h:commandLink>

            </span>
                <ui:repeat value="#{transactions_byaccount.pages}" var="itemx">
                    <span style="font-weight: #{itemx == transactions_byaccount.currentPageNo ? 'bold' : 'lighter' }">
                    <h:commandLink>
                        <h:outputText value="#{itemx}"></h:outputText>
                        <f:param name="pageNo" value="#{itemx}" />
                        <f:param name="accountId" value="#{param.accountId}" />
                        <f:param name="sortOrder" value="#{param.sortOrder}" />
                        <f:param name="orderColumn" value="#{param.orderColumn}" />

                    </h:commandLink>
                </span>
            </ui:repeat>                

        <span>
            <h:commandLink title="Go to page next page">
                <h:outputText value="next"></h:outputText>
                    <f:param name="pageNo" value="#{transactions_byaccount.nextPage}" />
                    <f:param name="accountId" value="#{param.accountId}" />
                    <f:param name="sortOrder" value="#{param.sortOrder}" />
                    <f:param name="orderColumn" value="#{param.orderColumn}" />
            </h:commandLink>
        </span>
        <span>
            <h:commandLink title="Go to page last page">
                <h:outputText value="last"></h:outputText>
                    <f:param name="pageNo" value="#{transactions_byaccount.lastPage}" />
                    <f:param name="accountId" value="#{param.accountId}" />
                    <f:param name="sortOrder" value="#{param.sortOrder}" />
                    <f:param name="orderColumn" value="#{param.orderColumn}" />

            </h:commandLink>                
        </span>         
    </div>
    <div class="currentPagerIndex">

    </div>
</ui:define>
<ui:define name="maincontent">
    <table class="datatable">
        <thead>
            <tr class="headRow">
                <td>datetransaction</td>
                <td>description</td>
                <td>amount</td>
                <td>Edit</td>
                <td>Delete</td>
            </tr>
        </thead>
        <ui:repeat value="#{transactions_byaccount.pageList}" var="itmy">
            <tr class="dataRow">
                <td class="dataCell cltdtransactionsdatetransaction">
                      <h:outputText value="#{itmy.datetransaction}" >
                            <f:convertDateTime pattern="EEE dd-MMM-yyyy HH:mm" />
                          </h:outputText>
                </td>
                <td class="dataCell cltdtransactionsdescription">#{itmy.description}</td>
                <td class="dataCell cltdtransactionsamount">#{itmy.amount}</td>
                <td style="width: 45px">
                    <span class="pagerDBspan" style="font-weight: bold;">                   
                        <h:link outcome="transactions_edit" style="font-weight: bold;">
                            <h:outputText value="Edit"></h:outputText>
                            <f:param name="pageNo" value="#{param.pageNo}" />
                            <f:param name="itemId" value="#{itmy.id}" />
                        </h:link>
                    </span>                 
                </td>
                <td style="width: 45px">
                    <span class="pagerDBspan" style="font-weight: bold;">
                        <h:link  outcome="transactions_edit" >
                            <h:outputText value="Delete"></h:outputText>
                            <f:param name="pageNo" value="#{param.pageNo}" />
                            <f:param name="itemId" value="#{itmy.id}" />
                            <f:param name="deleteFlag" value="true" />                                  
                        </h:link>       
                    </span>                 
                </td>
            </tr>
            <tr class="dataRow">
                <td class="dataCell"></td>
                <td class="dataCell" colspan="2">
                    <h:selectOneMenu value="#{itmy.fkCategoriesId}" >
                        <f:selectItems value="#{categories_edit.categories}"/>
                    </h:selectOneMenu>
                </td>
                <td colspan="2">
                    <span class="pagerDBspan" style="font-weight: bold;">
                            <h:commandLink action="#{transactions_byaccount.updateCategory('', itmy)}" >
                                <h:outputText value="Update"></h:outputText>        
                                <f:param name="pageNo" value="#{param.pageNo}" />
                                <f:param name="accountId" value="#{param.accountId}" />
                                <f:param name="sortOrder" value="#{param.sortOrder}" />
                                <f:param name="orderColumn" value="#{param.orderColumn}" />                                                                         
                            </h:commandLink>
                        </span>                                         
                    </td>
                </tr>
                <tr>
                    <td class="cssBottomLine" colspan="0"></td>
                </tr>                   
            </ui:repeat>
        </table>
    </ui:define>

    <ui:define name="bottomoperationalbarhost">
    </ui:define>

</ui:composition>
</html>