PrimeFaces PieChart无法正常工作

Question

im having trouble getting the basic primefaces pie chart working. im using primefaces 4.0, eclipse kepler and glassfish 4.0 The error im getting is:

java.lang.ClassCastException: java.lang.String cannot be cast to org.primefaces.model.chart.PieChartModel

xhtml:

<p:pieChart value="chart.model" legendPosition="w" />

Java:

package server;

import org.primefaces.model.chart.PieChartModel;
import javax.annotation.PostConstruct;
import java.io.Serializable;
import javax.faces.bean.ManagedBean;

public class Chart  implements Serializable
{

    private static final long serialVersionUID = 1L;

    private PieChartModel model;
    public Chart()
    {
        model = new PieChartModel();
        model.set("Brand1", 540);
        model.set("Brand2", 325);
        model.set("Brand3", 702);
        model.set("Brand4", 421);       
    }
    public PieChartModel getModel()
    {
        return model;
    }
}

Any ideas what I am doing wrong? Thanks

Answer 1

Your error comes from this:

<p:pieChart value="chart.model" legendPosition="w" />

Your value should be: value="#{chartBean.chart.model}"

Where chartBean is an annotated ManagedBean.

@ManagedBean(name="chartBean")
@YOURSCOPE (might be Request, Session etc...)
public class ChartBean implements Serializable{
  Chart chart;

  //you should initialize your bean in the constructor, or somewhere in the class, like
  public ChartBean(){
    ...
    Chart = new Chart();
    ...
  }

  public Chart getChart(){
    return this.chart;
  }
}