我有一个应用程序,我有一个级联下拉列表,一个简单的下拉列表和一个提交命令按钮.我希望通过从下拉列表中选择各种标准来显示数据表中的报告.一切正常,除非我想从儿童下拉菜单中选择标准.它没有与托管bean中的值绑定(通过调试发现).这是我的代码:
XHTML:
XHTML:
<h:outputText value="Exchange"/>
<p:selectOneMenu style="width: 150px" value="#{reportBean.exchange}">
<f:selectItem itemLabel="--select--" itemValue="--select--"/>
<f:selectItem itemLabel="NSE" itemValue="nse"/>
<f:selectItem itemLabel="BSE" itemValue="bse"/>
<p:ajax update="sym" listener="#{reportBean.wow}"/>
</p:selectOneMenu>
<h:outputText value="Scrip Symbol :"/>
<p:selectOneMenu value="#{reportBean.scripID}" id="sym" style="width: 100px">
<f:selectItem itemLabel="All" itemValue="0"/>
<f:selectItems var="scrip" value="#{reportBean.sl}" itemLabel="#{scrip.scripSymbol}" itemValue="#{scrip.scripID}"/>
</p:selectOneMenu>
<h:outputText value="Order Type :"/>
<p:selectOneMenu style="width: 100px" value="#{reportBean.orderType}">
<f:selectItem itemLabel="All" itemValue="All"/>
<f:selectItem itemLabel="Buy" itemValue="B"/>
<f:selectItem itemLabel="Sell" itemValue="S"/>
</p:selectOneMenu>
<p:commandButton ajax="true" update="dt" value="Submit" action="#{reportBean.getTradeByUserName()}" type="submit"/>
</h:panelGrid>
<p:dataTable id="dt" var="Trade" widgetvar="scripTab"
emptyMessage="No Trade found with given criteria"
value="#{reportBean.TradeList}"
paginator="true" paginatorTemplate="{CurrentPageReport} {FirstPageLink} {PrevIoUsPageLink} {PageLinks} {NextPageLink} {LastPageLink}"
rowsPerPageTemplate="3,5,10" rows="3" >
<p:column>....
托管bean代码:
public void wow()
{
sl=getAllScripByExchange(exchange);
}
public Integer getScripID() {
return scripID;
}
public void setScripID(Integer scripID) {
MasterScrip sm =getScripByID(scripID);
if(sm!=null)
this.scripSymbol=sm.getScripSymbol();
this.scripID = scripID;
}
public List<TradeStock> getTradeList() {
return TradeList;
}
public void setTradeList(List<TradeStock> TradeList) {
this.TradeList = TradeList;
}
public List<service.TradeStock> getTradeByUserName()
{
HttpServletRequest request = (HttpServletRequest)FacesContext.getCurrentInstance().getExternalContext().getRequest();
HttpSession session = request.getSession(true);
String uname = session.getAttribute("uname").toString();
TradeList= getTradeReport(scripID,uname,exchange,orderType);
return TradeList;
}
豆方法:
@Override
public Collection<TradeStock> getTradeReport(Integer scripID,String uname,String exchange,String TradeType) {
String strQuery = null;
strQuery = "Select t from TradeStock t where t.userName.userName = :userName ";
if(! exchange.equalsIgnoreCase("All"))
{
strQuery += " and t.scripID.exchange = '" + exchange + "'";
}
if(scripID>0)
{
strQuery += " and t.scripID.scripID = " + scripID;
}
if(! TradeType.equalsIgnoreCase("All"))
{
strQuery += " and t.orderID.buySell = '" + TradeType + "'";
}
Collection<TradeStock> c = em.createquery(strQuery).setParameter("userName",uname).getResultList();
return c;
}
为什么值不绑定到bean道具?我如何解决它?(我关心的问题是昨天相同的代码工作,但今天当我运行相同的代码时,它开始困扰我).
编辑:面-配置
<faces-config version="2.0"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-facesconfig_2_0.xsd">
<managed-bean>
<managed-bean-name>userReportBean</managed-bean-name>
<managed-bean-class>UserReportBean</managed-bean-class>
<managed-bean-scope>request</managed-bean-scope>
</managed-bean>
<navigation-rule>
<from-view-id>/adminpages/editScrip.xhtml</from-view-id>
<navigation-case>
<from-action>#{manageScrip.updateScrip}</from-action>
<from-outcome>success</from-outcome>
<to-view-id>/adminpages/manageScrip.xhtml</to-view-id>
</navigation-case>
</navigation-rule>
<navigation-rule>
<from-view-id>/adminpages/addScrip.xhtml</from-view-id>
<navigation-case>
<from-action>#{manageScrip.addScrip}</from-action>
<from-outcome>success</from-outcome>
<to-view-id>/adminpages/manageScrip.xhtml</to-view-id>
</navigation-case>
</navigation-rule>
<navigation-rule>
<from-view-id>/adminpages/manageScrip.xhtml</from-view-id>
<navigation-case>
<from-action>#{manageScrip.returnEdit}</from-action>
<from-outcome>success</from-outcome>
<to-view-id>/adminpages/editScrip.xhtml</to-view-id>
</navigation-case>
</navigation-rule>
<managed-bean>
<managed-bean-name>equityBean</managed-bean-name>
<managed-bean-class>beans.equityBean</managed-bean-class>
<managed-bean-scope>request</managed-bean-scope>
</managed-bean>
<managed-bean>
<managed-bean-name>reportBean</managed-bean-name>
<managed-bean-class>beans.reportBean</managed-bean-class>
<managed-bean-scope>request</managed-bean-scope>
</managed-bean>
</faces-config>
如果托管bean被@RequestScoped放置在请求范围内,则会发生这种情况.每个HTTP请求(包括Ajax请求)都会创建一个全新的bean实例,所有属性都设置为default.这样< f:selectItems> list变为空,因此在模型中没有设置值.
通过@ViewScoped将bean放在视图范围中应该可以解决这个问题.
也可以看看:
> How to choose the right bean scope?
更新:你应该删除那些< managed-bean> faces-config.xml中的定义.这是旧JSF 1.x注册bean的方式的遗留问题.它们只会覆盖@ManagedBean配置的JSF 2.x方式.
与您的具体问题没有直接关系,但那些< navigation-case> JSF 2.x中的条目是多余的.也许您错误地阅读了旧的JSF 1.x书籍/教程/资源而不是JSF 2.x的书籍/教程/资源?
与具体问题无关,你在getTradeReport()方法中认真对待SQL injection attack hole.您永远不应该在sql / JPQL字符串中串联连接用户控制的变量.使用参数化查询代替setParameter().另见CSRF,XSS and SQL Injection attack prevention in JSF.