最近公司给我一个任务，就是利用arcgis api for flex实现在地图上点（业务数据）直接显示饼状图以及柱状图的专题图制作，而不是通过点击点显示气泡窗口的形式来实现，这个公司已经实现了。
经过一段时间的摸索，参照一些网上资源，目前大概弄出来了，里面还有待完善的地方的。
效果图如下：
（1）Chart.mxml，主要的展示地图专题图效果的页面
<pre><?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
xmlns:esri="http://www.esri.com/2008/ags"
pageTitle="Charts in infowindow" xmlns:symbols="com.esri.ags.symbols.*">
<fx:Style>
.chartStyle
{
borderThickness: 0;
infoPlacement: center;
backgroundAlpha: 0;
infoOffsetX: 0;
infoOffsetY: 0;
paddingLeft: 0;
paddingRight: 0;
paddingTop: 0;
paddingBottom: 0;
}
</fx:Style>
<fx:Script>
<![CDATA[
import com.esri.ags.geometry.MapPoint;
import com.esri.ags.FeatureSet;
import com.esri.ags.Graphic;
import com.esri.ags.events.MapEvent;
import
com.esri.ags.tasks.QueryTask;
import
com.esri.ags.tasks.supportClasses.Query;
import
mx.collections.ArrayCollection;
import
mx.controls.Alert;
import
mx.events.FlexEvent;
import
mx.rpc.AsyncResponder;
protected
function
myMap_initializeHandler(event:MapEvent):
void
{
var
pie:MapPoint =
new
MapPoint(
113.55185
,
22.82289
);
var
column:MapPoint =
new
MapPoint(
113.59637985600011
,
22.758225999000047
);
var
bar:MapPoint =
new
MapPoint(
113.52757794
,
22.84012158
);
var
gpie:Graphic =
new
Graphic(pie);
var
gcolumn:Graphic =
new
Graphic(column);
var
gbar:Graphic =
new
Graphic(bar);
//g.attributes = new Object();
var
thematic:ArrayCollection =
new
ArrayCollection(
[
{ Name:
"危化品1"
, Rate:
25
},
{ Name:
"危化品2"
, Rate:
15
},
{ Name:
"危化品3"
, Rate:
23
}
]);
//g.attributes.thematic = thematic;
gpie.attributes = thematic;
gcolumn.attributes = thematic;
gbar.attributes = thematic;
this
.myGraphicsLayerpie.add(gpie);
this
.myGraphicsLayercolumn.add(gcolumn);
this
.myGraphicsLayerbar.add(gbar);
}
]]>
</fx:Script>
<fx:Declarations>
<esri:InfoSymbol id=
"infoSymbolpie"
infoRenderer=
"InfoRendererPieChart"
containerStyleName=
"chartStyle"
</esri:InfoSymbol>
<esri:InfoSymbol id=
"infoSymbolcolumn"
infoRenderer=
"InfoRendererColumnChart"
containerStyleName=
"chartStyle"
</esri:InfoSymbol>
<esri:InfoSymbol id=
"infoSymbolbar"
infoRenderer=
"InfoRendererBarChart"
containerStyleName=
"chartStylee"
</esri:InfoSymbol>
</fx:Declarations>
<esri:Map id=
"myMap"
load=
"myMap_initializeHandler(event)"
<esri:extent>
<esri:Extent xmin=
"113.284171273203"
ymin=
"22.6348519473499"
xmax=
"113.774816132605"
ymax=
"22.9103935318251"
<esri:spatialReference>
<esri:SpatialReference wkid=
"4326"
/>
</esri:spatialReference>
</esri:Extent>
</esri:extent>
<esri:ArcGISTiledMapServiceLayer url=
"http://localhost:6080/ArcGIS/rest/services/ns_new/MapServer"
/>
<esri:GraphicsLayer id=
"myGraphicsLayercolumn"
symbol=
"{infoSymbolcolumn}"
</esri:GraphicsLayer>
<esri:GraphicsLayer id=
"myGraphicsLayerpie"
symbol=
"{infoSymbolpie}"
</esri:GraphicsLayer>
<esri:GraphicsLayer id=
"myGraphicsLayerbar"
symbol=
"{infoSymbolbar}"
</esri:GraphicsLayer>
</esri:Map>
</s:Application>
</pre>
（2）InfoRendererBarChart.mxml、InfoRendererColumnChart.mxml、InfoRendererPieChart.mxml，分别是柱状图以及饼状图实现的页面
1.InfoRendererBarChart.mxml
<pre><?xml version=
"1.0"
encoding=
"utf-8"
?>
<s:VGroup xmlns:fx=
"http://ns.adobe.com/mxml/2009"
xmlns:s=
"library://ns.adobe.com/flex/spark"
xmlns:mx=
"library://ns.adobe.com/flex/mx"
clipAndEnableScrolling=
"true"
creationComplete=
"creationCompleteHandler()"
implements
"mx.core.IDataRenderer"
width=
"100"
height=
"100"
<fx:Script>
<![CDATA[
private
var
_data:
Object
;
[Bindable]
// implement IDataRenderer
public
function
get
data():
Object
{
return
_data;
}
public
function
set
data(value:
Object
):
void
{
_data = value;
}
private
function
creationCompleteHandler():
void
{
}
]]>
</fx:Script>
<mx:BarChart id=
"columnChart"
width=
"100%"
height=
"100%"
dataProvider=
"{data}"
showDataTips=
"true"
<mx:series>
<mx:BarSeries id=
"barSeries"
xField=
"Rate"
/>
</mx:series>
<mx:verticalAxis>
<mx:CategoryAxis id=
"barAxis"
categoryField=
"Name"
/>
</mx:verticalAxis>
<mx:verticalAxisRenderers>
<mx:AxisRenderer axis=
"{barAxis}"
showLabels=
"false"
/>
</mx:verticalAxisRenderers>
</mx:BarChart>
</s:VGroup>
</pre>
2.InfoRendererColumnChart.mxml
<pre>
<?xml version=
"1.0"
encoding=
"utf-8"
?>
<s:VGroup xmlns:fx=
"http://ns.adobe.com/mxml/2009"
xmlns:s=
"library://ns.adobe.com/flex/spark"
xmlns:mx=
"library://ns.adobe.com/flex/mx"
clipAndEnableScrolling=
"true"
creationComplete=
"creationCompleteHandler()"
implements
"mx.core.IDataRenderer"
width=
"100"
height=
"100"
<fx:Script>
<![CDATA[
private
var
_data:
Object
;
[Bindable]
// implement IDataRenderer
public
function
get
data():
Object
{
return
_data;
}
public
function
set
data(value:
Object
):
void
{
_data = value;
}
private
function
creationCompleteHandler():
void
{
}
]]>
</fx:Script>
<mx:ColumnChart id=
"columnChart"
width=
"100%"
height=
"100%"
dataProvider=
"{data}"
showDataTips=
"true"
<mx:series>
<mx:ColumnSeries id=
"columnSeries"
yField=
"Rate"
/>
</mx:series>
<mx:horizontalAxis>
<mx:CategoryAxis id=
"columnAxis"
categoryField=
"Name"
/>
</mx:horizontalAxis>
<mx:horizontalAxisRenderers>
<mx:AxisRenderer axis=
"{columnAxis}"
showLabels=
"false"
/>
</mx:horizontalAxisRenderers>
</mx:ColumnChart>
</s:VGroup>
</pre>
3.InfoRendererPieChart.mxml
<pre>
<?xml version=
"1.0"
encoding=
"utf-8"
?>
<s:VGroup xmlns:fx=
"http://ns.adobe.com/mxml/2009"
xmlns:s=
"library://ns.adobe.com/flex/spark"
xmlns:mx=
"library://ns.adobe.com/flex/mx"
clipAndEnableScrolling=
"true"
creationComplete=
"creationCompleteHandler()"
implements
"mx.core.IDataRenderer"
width=
"100"
height=
"100"
<fx:Script>
<![CDATA[
private
var
_data:
Object
;
[Bindable]
// implement IDataRenderer
public
function
get
data():
Object
{
return
_data;
}
public
function
set
data(value:
Object
):
void
{
_data = value;
}
private
function
creationCompleteHandler():
void
{
}
]]>
</fx:Script>
<mx:PieChart id=
"pieChart"
width=
"100%"
height=
"100%"
dataProvider=
"{data}"
showDataTips=
"true"
<mx:series>
<mx:PieSeries field=
"Rate"
labelPosition=
"callout"
nameField=
"Name"
</mx:PieSeries>
</mx:series>
</mx:PieChart>
</s:VGroup>
</pre>
上述的总体实现思路是这样的：核心是InfoSymbol，InfoSymbol自定义infoRenderer绑定专题图的模版，比如InfoRendererBarChart.mxml、InfoRendererColumnChart.mxml、InfoRendererPieChart.mxml；程序初始化的时候生成了一些带有统计信息的Graphic添加到地图上，这些Graphic对象的attributes属性集合来保存各个统计的对象，每个统计的对象包含两个字段：Name表示危化品名称，Rate表示占有比重，下面我们会在InfoSymbol的定义中再次看到这两个字段。当定义好这些Graphic对象以后，我们就可以把它们添加到设置了InfoSymbol符号的GraphicLayer上了。在InfoSymbol的定义中，我们可以看到，在这个InfoSymbol中添加了一个饼图组件PieChart，这个饼图的dataProvider属性绑定的是{data}，它代表的其实就是Graphic对象的attributes属性。你可以简单地这样认为：InfoSymbol中的data代表的就是其对应的Graphic对象的attributes属性。其他的柱状图也是同理的。
既然在InfoSymbol中可以获得Graphic的属性信息，那么根据Graphic的属性信息来绘制不同的专题图就是水到渠成的事情了。
样式代码解析：
<pre>
.chartStyle
{
borderThickness:
0
;
/显示专题图的边框宽度/
infoPlacement: center;
/显示专题图的位置，这里是中心/
backgroundAlpha:
0
;
/显示专题图的背景透明度，这里设置为0，是为了隐藏背景/
infoOffsetX:
0
;
/显示专题图的X偏移，设置0，不然会偏离原始点位置/
infoOffsetY:
0
;
/显示专题图的Y偏移，设置0，不然会偏离原始点位置/
paddingLeft:
0
;
/显示专题图的位置偏移，设置0，不然会偏离原始点位置/
paddingRight:
0
;
/显示专题图的位置偏移，设置0，不然会偏离原始点位置/
paddingTop:
0
;
/显示专题图的位置偏移，设置0，不然会偏离原始点位置/
paddingBottom:
0
;
/显示专题图的位置偏移，设置0，不然会偏离原始点位置/
}
</pre>
需要完善优化之处：目前GraphicsLayer定义了三个（pie，bar，column),然后各自绑定不同的infoSymbol（pie，bar，column)。这样显的有点冗余了，其实只要定义一个GraphicsLayer，然后动态的判断绑定的是哪个infoSymbol。
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