柱状专题图实现例子

柱状专题图实现例子

原文：http://bbs.esrichina-bj.cn/esri/viewthread.php?tid=7613
//得到制作专题图的图层ID
  。。。。。。。。。。
  int  layerID=3;
 
//得到专题图分析元素的属性名称列表
String[]  fieldName=new String[2];
fieldName[0]="POP1990";
fieldName[1]="POP1999";


//得到专题图分析的图层对象（FeatureLayer）
AGSLocalMapResource res = (AGSLocalMapResource) this.webContext
     .getResources().get("ags0");
   MapServer mapServer = res.getLocalMapServer();
    ILayer fiLayer = mapServer.getLayer(mapServer.getMapName(0),  layerID);
   FeatureLayer fLayer = (FeatureLayer) fiLayer;


//创建ChartRenderer对象  注意：在web adf中创建AO对象用AGSLocalMapResource对象的createArcObject（String）方法
   ChartRenderer chartRender = (ChartRenderer) res
     .createArcObject(ChartRenderer.getClsid());
 
//在IRendererFileds中指定柱状图各列显示字段值   
   IRendererFields rendererFields = chartRender;
   rendererFields.addField(fieldName[0], null);
   rendererFields.setFieldAlias(0, rendererFields.getField(0));
    rendererFields.addFieldfieldName[1], null);
   rendererFields.setFieldAlias(1, rendererFields.getField(1));

//查出各元素指定属性最大值  必须的
QueryFilter queryFilter = (QueryFilter) res
     .createArcObject(QueryFilter.getClsid());
   queryFilter.addField(fieldName[0]);
    queryFilter.addField(fieldName[1]);
   ICursor cursor = fLayer.ITable_search(queryFilter, true);
   int numFields = 2; //柱状图列的个数
   int[] fieldIndecies = new int[numFields];
   fieldIndecies[0] = fLayer.findField(fieldName[0]);
    fieldIndecies[1] = fLayer.findField(fieldName[1]);
   double maxValue = 0;
     boolean firstValue = true;
   IRowBuffer row = cursor.nextRow();
   while (row != null) {
    String fieldvalue = "";
    for (int fieldIndex = 0; fieldIndex < numFields; fieldIndex++) {
     double fieldValue = Double.parseDouble(row.getValue(
       fieldIndecies[fieldIndex]).toString());
     if (firstValue) {
      maxValue = fieldValue;
           firstValue = false;
     }
     if (fieldValue > maxValue)
      maxValue = fieldValue;
         }
    row = cursor.nextRow();
   }
 

//实例化图表对象
  BarChartSymbol barChartSymbol = (BarChartSymbol) res.createArcObject(BarChartSymbol.getClsid());
    
   IChartSymbol chartSymbol = barChartSymbol;
   barChartSymbol.setWidth(10);
  IMarkerSymbol markerSymbol =  barChartSymbol;
   chartSymbol.setMaxValue(maxValue);
   markerSymbol.setSize(60);
   

//设置柱状图每列填充颜色及线颜色

   ISymbolArray symbolArray = barChartSymbol;
   SimpleFillSymbol   fillSymbol1 = (SimpleFillSymbol) res.createArcObject(SimpleFillSymbol.getClsid());
   IRgbColor   rgbColor1 = (RgbColor) res.createArcObject(RgbColor .getClsid());
   
   rgbColor1.setRed(255);
   rgbColor1.setGreen(0);
   rgbColor1.setBlue(0);
   rgbColor1.setUseWindowsDithering(true);
   
   ILineSymbol ilinesym1 = (ILineSymbol) res.createArcObject(SimpleLineSymbol.getClsid());
   ilinesym1.setColor(rgbColor1);
   ilinesym1.setWidth(1);
   fillSymbol1.setOutline(ilinesym1);
   
   fillSymbol1.setColor(rgbColor1);
   barChartSymbol.addSymbol(fillSymbol1);
   
   SimpleFillSymbol fillSymbol2 = (SimpleFillSymbol) res .createArcObject(SimpleFillSymbol.getClsid());
   
   IRgbColor rgbColor2 = (RgbColor) res.createArcObject(RgbColor .getClsid());
   
   rgbColor2.setRed(238);
   rgbColor2.setGreen(195);
   rgbColor2.setBlue(235);
   rgbColor2.setUseWindowsDithering(true);
   
   ILineSymbol ilinesym2 = (ILineSymbol) res.createArcObject(SimpleLineSymbol.getClsid());
   ilinesym2.setColor(rgbColor2);
   ilinesym2.setWidth(1);
   fillSymbol2.setOutline(ilinesym2);
   fillSymbol2.setColor(rgbColor2);
   barChartSymbol.addSymbol(fillSymbol2);
 
    chartRender.setChartSymbolByRef(chartSymbol);
    chartRender.setUseOverposter(false);
  //设置FeatureRenderer ChartRenderer对象
  fLayer.setRendererByRef(chartRender);
   
  //刷新地图显示图表
   map1.refresh();
   this.webContext.refresh();