第二篇 arcgis api for js 根據座標生成點
阿新 • • 發佈：2019-02-19
要點
1、生成點要素
2、地圖載入順序及map.on事件順序；
3、分析兩種不同圖層載入方式對點生成的影響；
可執行程式碼：
</pre><pre><%-- Created by IntelliJ IDEA. User: neil Date: 2015/8/16 Time: 18:48 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <meta name="viewport" content="initial-scale=1, maximum-scale=1,user-scalable=no"> <title>SimpleMarkerSymbol with SVG Path - Simplified</title> <link rel="stylesheet" href="http://js.arcgis.com/3.14/dijit/themes/claro/claro.css"> <link rel="stylesheet" href="http://js.arcgis.com/3.14/dojox/widget/ColorPicker/ColorPicker.css"> <link rel="stylesheet" href="http://js.arcgis.com/3.14/esri/css/esri.css"> <style> html, body, #map { height: 100%; width: 100%; margin: 0; padding: 0; } </style> <script src="http://js.arcgis.com/3.14/"></script> <script> var map; require([ "esri/map", "esri/geometry/Point", "esri/SpatialReference", "esri/symbols/SimpleMarkerSymbol", "esri/graphic" ], function(Map, Point, SpatialReference, SimpleMarkerSymbol, Graphic) { map = new Map("map", { basemap: "topo", center: [113, 37], zoom: 13 }); map.on("load", function() { ShowLocation(113,37); }); function ShowLocation(x, y) { var point = new Point(x, y, new SpatialReference({wkid:4326})); var simpleMarkerSymbol = new SimpleMarkerSymbol(); var graphic = new Graphic(point, simpleMarkerSymbol); map.graphics.add(graphic); }; }); </script> </head> <div id="map"></div> </body> </html>
注意，只有當map.on事件緊跟map=new Map(...);之後，才能正常顯示點；
下面換成另一種方式載入瓦片圖層，將上面方法程式碼替換如下：
function(Map, Tiled,Point, SpatialReference, SimpleMarkerSymbol, Graphic) { map = new Map("map"); map.on("load", function() { ShowLocation(113,37); }); var tiled = new Tiled("http://server.arcgisonline.com/arcgis/rest/services/World_Topo_Map/MapServer"); map.addLayer(tiled); function ShowLocation(x, y) { var point = new Point(x, y, new SpatialReference({wkid:4326})); var simpleMarkerSymbol = new SimpleMarkerSymbol(); var graphic = new Graphic(point, simpleMarkerSymbol); map.graphics.add(graphic); };
採用第二種方式同樣可以生成點。下面採用第三種方式，待續……