我在通过java素数面生成直方图时遇到了问题。我有这个xhtml文件。
<!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:ui="http://java.sun.com/jsf/facelets"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:p="http://primefaces.org/ui">
<ui:define name="content">
<h1 class="title ui-widget-header ui-corner-all">Charts - Bar</h1>
<div class="entry">
<p>BarChart displays a CartesianChartModel.</p>
<p:barChart id="basic" value="#{ChartBean.categoryModel}" legendPosition="ne"
title="Basic Bar Chart" min="0" max="200" style="height:300px"/>
</div>
</ui:define>
</html>
我还有这个ChartBean.java文件，上面定义了ChartBean.categoryModel
package exmpl;
//package org.primefaces.examples.view;
import java.io.Serializable;
import java.util.ArrayList;
import exmpl.controller.QueryBean;
import org.primefaces.model.chart.CartesianChartModel;
import org.primefaces.model.chart.ChartSeries;
public class ChartBean implements Serializable {
private CartesianChartModel categoryModel;
public ChartBean() {
System.out.print("Inside constructir");
createCategoryModel();
}
public CartesianChartModel getCategoryModel() {
return categoryModel;
}
private void createCategoryModel() {
System.out.print("Inside Function Category Model");
QueryBean obj = new QueryBean();
ArrayList<Integer> employeeage = obj.employeeAge();
System.out.print("After accessing QueryBean");
ArrayList<Integer> grp1 = new ArrayList<Integer>();
ArrayList<Integer> grp2 = new ArrayList<Integer>();
ArrayList<Integer> grp3 = new ArrayList<Integer>();
ArrayList<Integer> grp4 = new ArrayList<Integer>();
ArrayList<Integer> grp5 = new ArrayList<Integer>();
ArrayList<Integer> grp6 = new ArrayList<Integer>();
ArrayList<Integer> grp7 = new ArrayList<Integer>();
for(Integer i : employeeage)
{
if(i.intValue() > 0 && i.intValue() <= 20 )
{
grp1.add(i);
}
else if(i.intValue() > 20 && i.intValue() <= 40 )
{
grp2.add(i);
}
else if(i.intValue() > 40 && i.intValue() <= 50 )
{
grp3.add(i);
}
else if(i.intValue() > 50 && i.intValue() <= 60 )
{
grp4.add(i);
}
else if(i.intValue() > 60 && i.intValue() <= 70 )
{
grp5.add(i);
}
else if(i.intValue() > 70 && i.intValue() <= 80 )
{
grp6.add(i);
}
else
{
grp7.add(i);
}
}
int size1 = grp1.size();
int size2 = grp2.size();
int size3 = grp3.size();
int size4 = grp4.size();
int size5 = grp5.size();
int size6 = grp6.size();
int size7 = grp7.size();
categoryModel = new CartesianChartModel();
ChartSeries employee = new ChartSeries();
patient.setLabel("Employees");
employee.set("0-20", size1);
employee.set("21-40", size2);
employee.set("41-50", size3);
employee.set("51-60", size4);
employee.set("61-70", size5);
employee.set("71-80", size6);
employee.set("80+", size7);
categoryModel.addSeries(employee);
}
}
所以第一个xhtml中的ui.xhtml模板看起来像这个
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:p="http://primefaces.org/ui">
<f:view contentType="text/html">
<h:head>
<f:facet name="first">
<meta http-equiv="X-UA-Compatible" content="IE=Edge"/>
<meta content='text/html; charset=UTF-8' http-equiv="Content-Type"/>
<title>PrimeFaces - ShowCase</title>
<!-- <link rel="shortcut icon" type="image/png" href="#{request.contextPath}/images/favicon.png" /> -->
</f:facet>
<link type="text/css" rel="stylesheet" href="#{request.contextPath}/css/default.css" />
<link type="text/css" rel="stylesheet" href="#{request.contextPath}/css/syntaxhighlighter/syntaxhighlighter.css" />
<ui:insert name="head"></ui:insert>
<script type="text/javascript">
$(function() {$('.sidebar a').hover(function() {$(this).toggleClass('ui-state-hover');})});
</script>
<script type="text/javascript">
var _gaq = _gaq || [];
_gaq.push(['_setAccount', 'UA-12200033-3']);
_gaq.push(['_trackPageview']);
(function() {
var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);
})();
</script>
</h:head>
<h:body>
<div id="header" class="ui-widget ui-widget-header">
<div id="logo">
<img src="#{request.contextPath}/images/logo.png" alt="Logo"/>
</div>
</div>
<div id="page" class="ui-widget">
<div id="sidebar" class="ui-widget-content ui-corner-bottom ui-helper-clearfix ui-shadow">
<h3 class="ui-widget ui-widget-header ui-corner-all submenu-title ui-state-highlight">Charts</h3>
<div class="submenu-content">
<table>
<tr>
<td style="width:33%">
<ul>
<li><a href="#{request.contextPath}/ui/barChart.jsf">Bar</a></li>
</ul>
</td>
<td style="width:33%">
<ul>
</ul>
</td>
</tr>
</table>
</div>
</div>
<div id="content">
<div class="post">
<ui:insert name="content">...</ui:insert>
</div>
</div>
<div style="clear: both;"></div>
</div>
<ui:insert name="footer">
<div id="footer" class="ui-widget ui-widget-header ui-corner-all">
<p class="copyright">Running #{build.primefacesVersion} on #{build.jsfVersion}</p>
</div>
</ui:insert>
<ui:insert name="status">
<p:ajaxStatus style="width:64px;height:64px;position:fixed;right:5px;bottom:5px">
<f:facet name="start">
<p:graphicImage value="/images/loading.gif" />
</f:facet>
<f:facet name="complete">
<h:outputText value="" />
</f:facet>
</p:ajaxStatus>
</ui:insert>
<ui:insert name="highlight">
<script language="javascript" src="#{request.contextPath}/syntaxhighlighter/scripts/sh.js"></script>
<script language="javascript">
SyntaxHighlighter.all();
</script>
</ui:insert>
</h:body>
</f:view>
</html>
现在的问题是，当我运行上述文件时，什么都不会发生，也看不到任何显示。我是新手，因此无法指出我在哪里犯了错误。有人能帮我吗？
更新：当我在xhtml文件上运行时，我甚至看不到控制台上打印的inside constructor，它是在ChartBean()构造函数上写的
当然，您看不到构造函数的输出，因为它实际上从未使用所提供的代码进行过调用。要使您的bean在xhtml页面中可访问，您必须使用@Named或@ManagedBean注释。当您这样做时，当您在xhtml中引用bean（基于其作用域）时，将创建bean的实例。
@ManagedBean
@ViewScoped
public class ChartBean implements Serializable {
...
}
然后你可以在xhtml中使用它，如下所示：
#{chartBean.categoryModel}