chartdemo.java

在J2ME开发环境(NETBEANS)上使用LWUIT + J4LChart 实现精美的图表

package com.sun.lwuit.uidemo;
import com.sun.lwuit.Command;
import com.sun.lwuit.Form;
import com.sun.lwuit.events.ActionEvent;
import com.sun.lwuit.events.ActionListener;
import com.java4less.rchart.Chart;
import com.java4less.rchart.ChartLoader;
import com.java4less.rchart.gc.GraphicsProvider;
import com.java4less.rchart.lwuit.ChartViewer;
import com.java4less.rchart.util.Formats;
import com.sun.lwuit.Display;
import com.sun.lwuit.animations.Transition3D;
import com.sun.lwuit.geom.Dimension;
import com.sun.lwuit.layouts.BorderLayout;
import java.util.Date;


public class ChartDemo implements ActionListener {
    public Form form = new Form("J4LChart");
 
  Display display;
  Command nextExample= new Command("Next");
  Command previousExample= new Command("Previous");
  ChartViewer chartCanvas;
  ChartLoader loader;

  String[] examples={"areaChart.txt","areaCurves.txt","axisOnTop.txt","barChart3D.txt","barChart3D.txt","barChart.txt",
  "barImages.txt","bubbleChart.txt","candleStick.txt","combined2Positions.txt","combinedChart.txt","event.txt","linechart3D.txt",
  "linechart.txt","linechartClipping.txt","linechartNULLS.txt","MultiAxis.txt","MultiCharts.txt","patternFilling.txt",
  "piechart3D.txt","PieDrillDown.txt","radarChart.txt","realtime.txt","scatterChart.txt","stackedBar.txt","StackedMultiAxis.txt",
  "subpie1.txt","subpie2.txt","subpie3.txt","targetZones.txt"};

  int currentExample=0;

  /*
   * 初始化Chart,从文本读取chart图结构并显示
   */
    ChartDemo()
    {
        GraphicsProvider.setMode(GraphicsProvider.MODE_LWUIT);

        form.addCommand(previousExample);//上一个
        form.addCommand(nextExample);//下一个

        form.setCommandListener(this);
        chartCanvas=new ChartViewer();//chart视图
        chartCanvas.setPreferredSize(new Dimension(200,200));//设置大小
        loadChartFromFile("/txt/"+examples[currentExample]);//读取文本，设置chart
        form.setLayout(new BorderLayout());
        form.addComponent(BorderLayout.CENTER,chartCanvas);
        form.refreshTheme();
    }

  /*
   * 在读取TXT文件的同时，同时设置Chart里面的数值
   */
    private void createRealtimedata(ChartLoader loader) {

        java.util.Date now=java.util.Calendar.getInstance().getTime();
        loader.setParameter("XAXIS_INITIAL_DATE",Formats.formatDate(now,"dd/MM/yyyy hh:mm:ss"));
        //	create random data based on the time
        java.util.Calendar cal=java.util.Calendar.getInstance();
        String data1="";
        String data2="";
        for (int i=0;i<9;i++) {
                cal.setTime(new Date(cal.getTime().getTime()-2000));
                if (data1.length()>0) data1="|" + data1;
                data1=""+cal.get(java.util.Calendar.SECOND)+ data1;
                if (data2.length()>0) data2="|" + data2;
                data2=""+(cal.get(java.util.Calendar.SECOND)/6)+ data2;
        }

        loader.setParameter("SERIE_DATA_1",data1);
        loader.setParameter("SERIE_DATA_2",data2);

     }
  /*
   * 读取TXT文件并设置chart
   */
    public void loadChartFromFile(String filename) {
        ChartLoader cha=new ChartLoader();
        cha.loadFromFile(this.getClass().getResourceAsStream(filename),true);//读取文本
        //this.loader=cha;
        //********设置Chart数值
        //createRealtimedata(cha);
        //********设置Chart数值
        Chart c=cha.build(false,false);//建立chart
        chartCanvas.setChart(c);
        chartCanvas.getChart().setSize(chartCanvas.getWidth(),chartCanvas.getHeight());
        chartCanvas.repaintChart();
        form.setTitle(filename);
  	}

    public void actionPerformed(ActionEvent arg0) {
        if(arg0.getCommand()==nextExample)//读取上一个chart(TXT文本)
        {
            chartCanvas.getChart().stopUpdater();
            currentExample++;
            if(currentExample>=examples.length-1)
                currentExample=0;
            form.replace(chartCanvas, chartCanvas,Transition3D.createRotation(500, true));
            loadChartFromFile("/txt/"+examples[currentExample]);
            
        }
        else if(arg0.getCommand()==previousExample)//读取下一个chart(TXT文本)
        {
            chartCanvas.getChart().stopUpdater();
            currentExample--;
            if(currentExample<=0)
                currentExample=examples.length-1;
            form.replace(chartCanvas, chartCanvas,Transition3D.createRotation(500, false));
            loadChartFromFile("/txt/"+examples[currentExample]);

        }
    }
}