使用我的 esri 网络地图通过 ArcGIS API 为 JavaScript 创建缓冲区

using my esri webmap to make buffer with ArcGIS API for JavaScript

我可以加载我的 esri web 地图,但缓冲区不起作用。

我使用了来自 developers.arcgis.com/javascript 的示例,来自这条路径:https://developers.arcgis.com/javascript/jssamples/util_buffergraphic.html

并通过添加我的 web 地图 id 进行了修改并进行了一些更改。

<!DOCTYPE html>
<html>
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<!--The viewport meta tag is used to improve the presentation and behavior of the samples 
  on iOS devices-->
<meta name="viewport" content="initial-scale=1, maximum-scale=1,user-scalable=no">
<title>Buffer</title>

<link rel="stylesheet" href="http://js.arcgis.com/3.13/dijit/themes/claro/claro.css">
<link rel="stylesheet" href="http://js.arcgis.com/3.13/esri/css/esri.css">
<style>
   html, body {
    height: 100%;
    width: 100%;
    margin: 0; 
    padding: 0;
    overflow:hidden;
  }
  #leftPane{
    color:#000;
    width:250px;
    padding-bottom:15px;
  }
  #map{
    padding:0;
  }
  .details{
    font-size:14px;
    font-weight:600;
    padding-bottom:20px;
  }

  button{
    margin:2px;
    cursor:pointer;
  }
</style>

<script src="http://js.arcgis.com/3.13/"></script>
<script>
var map, tb,
        webmapId = "62847ab75c1b4f7d829a530b7c4432f2";

require(["dojo/dom",

        "dojo/_base/array",
        "dojo/parser",
        "dojo/query",
        "dojo/on",

        "esri/Color",
        "esri/config",
        "esri/map",
        "esri/arcgis/utils",
        "esri/graphic",

        "esri/geometry/normalizeUtils",
        "esri/tasks/GeometryService",
        "esri/tasks/BufferParameters",
  
        "esri/toolbars/draw",
  
        "esri/symbols/SimpleMarkerSymbol",
        "esri/symbols/SimpleLineSymbol",
        "esri/symbols/SimpleFillSymbol",
        
        "dijit/layout/BorderContainer",
        "dijit/layout/ContentPane",
        "dijit/form/Button", "dojo/domReady!"
        ],
      function(dom, array, parser, query, on, Color, esriConfig, Map, arcgisUtils, Graphic, normalizeUtils, GeometryService, BufferParameters, Draw, SimpleMarkerSymbol, SimpleLineSymbol, SimpleFillSymbol){

        parser.parse();


        esriConfig.defaults.geometryService = new GeometryService("http://tasks.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer");

        esriConfig.defaults.io.proxyUrl = "/proxy/";
        esriConfig.defaults.io.alwaysUseProxy = false;
  
        arcgisUtils.createMap(webmapId, "map").then(function (response) {
        map = response.map;
        });
        map.on("load", initToolbar);

       //Setup button click handlers
        on(dom.byId("clearGraphics"), "click", function(){
          if(map){
            map.graphics.clear();
          }
        });
        //click handler for the draw tool buttons
        query(".tool").on("click", function(evt){
          if(tb){
           tb.activate(evt.target.id);
          }
        });
        

      function initToolbar(evtObj) {
        tb = new Draw(evtObj.map);
        tb.on("draw-end", doBuffer);
      }

      function doBuffer(evtObj) {
        tb.deactivate();
        var geometry = evtObj.geometry, symbol;
        switch (geometry.type) {
           case "point":
             symbol = new SimpleMarkerSymbol(SimpleMarkerSymbol.STYLE_SQUARE, 10, new SimpleLineSymbol(SimpleLineSymbol.STYLE_SOLID, new Color([255,0,0]), 1), new Color([0,255,0,0.25]));
             break;
           case "polyline":
             symbol = new SimpleLineSymbol(SimpleLineSymbol.STYLE_DASH, new Color([255,0,0]), 1);
             break;
           case "polygon":
             symbol = new SimpleFillSymbol(SimpleFillSymbol.STYLE_NONE, new SimpleLineSymbol(SimpleLineSymbol.STYLE_DASHDOT, new Color([255,0,0]), 2), new Color([255,255,0,0.25]));
             break;
        }

          var graphic = new Graphic(geometry, symbol);
          map.graphics.add(graphic);

          //setup the buffer parameters
          var params = new BufferParameters();
          params.distances = [ dom.byId("distance").value ];
          params.outSpatialReference = map.spatialReference;
          params.unit = GeometryService[dom.byId("unit").value];
          //normalize the geometry 

          normalizeUtils.normalizeCentralMeridian([geometry]).then(function(normalizedGeometries){
            var normalizedGeometry = normalizedGeometries[0];
            if (normalizedGeometry.type === "polygon") {
              //if geometry is a polygon then simplify polygon.  This will make the user drawn polygon topologically correct.
              esriConfig.defaults.geometryService.simplify([normalizedGeometry], function(geometries) {
                params.geometries = geometries;
                esriConfig.defaults.geometryService.buffer(params, showBuffer);
              });
            } else {
              params.geometries = [normalizedGeometry];
              esriConfig.defaults.geometryService.buffer(params, showBuffer);
            }

          });
        }

        function showBuffer(bufferedGeometries) {
          var symbol = new SimpleFillSymbol(
            SimpleFillSymbol.STYLE_SOLID,
            new SimpleLineSymbol(
              SimpleLineSymbol.STYLE_SOLID,
              new Color([255,0,0,0.65]), 2
            ),
            new Color([255,0,0,0.35])
          );

          array.forEach(bufferedGeometries, function(geometry) {
            var graphic = new Graphic(geometry, symbol);
            map.graphics.add(graphic);
          });

        }
  });
</script>

</head>

<body class="claro">
<div data-dojo-type="dijit/layout/BorderContainer" 
     data-dojo-props="gutters:'true', design:'sidebar'" 
     style="width:100%;height:100%;">

  <div id="map" 
       data-dojo-type="dijit/layout/ContentPane" 
       data-dojo-props="region:'center'">
  </div>

  <div id="leftPane" 
       data-dojo-type="dijit/layout/ContentPane" 
       data-dojo-props="region:'left'">
    <div class="details">Pick a tool and draw on the map. The drawn graphic will be buffered based on the specified parameters.</div>
    <button type="button" class="tool" id="line">Line</button>
    <button type="button" class="tool" id="polyline">Polyline</button>
    <button type="button" class="tool" id="freehandpolyline">Freehand Polyline</button>
    <br/>
    <button type="button" class="tool" id="polygon">Polygon</button>
    <button type="button" class="tool" id="freehandpolygon">Freehand Polygon</button>
    <br/><hr />
    <div><b>Buffer Parameters</b></div>
    Distance:&nbsp;<input type="text" id="distance" size="5" value="25" />
    <select id="unit" style="width:100px;">
      <option value="UNIT_STATUTE_MILE">Miles</option>
      <option value="UNIT_FOOT">Feet</option>
      <option value="UNIT_KILOMETER">Kilometers</option>
      <option value="UNIT_METER">Meters</option>
      <option value="UNIT_NAUTICAL_MILE">Nautical Miles</option>
      <option value="UNIT_US_NAUTICAL_MILE">US Nautical Miles</option>
      <option value="UNIT_DEGREE">Degrees</option>
    </select><br />
    <button type="button" id="clearGraphics"  type="button">Clear Graphics</button>
  </div>
</div>
</body>
</html>

您正在使用 webmap,并且附加了不需要的 "load" 事件。下面是详细解释:

  1. 您的地图对象未定义,因为在 webmap 响应之前您正在调用地图的 "on" 方法。 (这不是必需的)

  2. 如果您得到 "response.map",则表示您的地图对象已加载。所以需要在 "load"

  3. 上附加事件
  4. 您的地图对象已经加载,所以只需要初始化您的绘图工具栏。

下面是工作代码:

<!DOCTYPE html>
<html>
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<!--The viewport meta tag is used to improve the presentation and behavior of the samples 
  on iOS devices-->
<meta name="viewport" content="initial-scale=1, maximum-scale=1,user-scalable=no">
<title>Buffer</title>

<link rel="stylesheet" href="http://js.arcgis.com/3.13/dijit/themes/claro/claro.css">
<link rel="stylesheet" href="http://js.arcgis.com/3.13/esri/css/esri.css">
<style>
   html, body {
    height: 100%;
    width: 100%;
    margin: 0; 
    padding: 0;
    overflow:hidden;
  }
  #leftPane{
    color:#000;
    width:250px;
    padding-bottom:15px;
  }
  #map{
    padding:0;
  }
  .details{
    font-size:14px;
    font-weight:600;
    padding-bottom:20px;
  }

  button{
    margin:2px;
    cursor:pointer;
  }
</style>

<script src="http://js.arcgis.com/3.13/"></script>
<script>
var map, tb,
        webmapId = "62847ab75c1b4f7d829a530b7c4432f2";

require(["dojo/dom",

        "dojo/_base/array",
        "dojo/parser",
        "dojo/query",
        "dojo/on",

        "esri/Color",
        "esri/config",
        "esri/map",
        "esri/arcgis/utils",
        "esri/graphic",

        "esri/geometry/normalizeUtils",
        "esri/tasks/GeometryService",
        "esri/tasks/BufferParameters",
  
        "esri/toolbars/draw",
  
        "esri/symbols/SimpleMarkerSymbol",
        "esri/symbols/SimpleLineSymbol",
        "esri/symbols/SimpleFillSymbol",
        
        "dijit/layout/BorderContainer",
        "dijit/layout/ContentPane",
        "dijit/form/Button", "dojo/domReady!"
        ],
      function(dom, array, parser, query, on, Color, esriConfig, Map, arcgisUtils, Graphic, normalizeUtils, GeometryService, BufferParameters, Draw, SimpleMarkerSymbol, SimpleLineSymbol, SimpleFillSymbol){

        parser.parse();


        esriConfig.defaults.geometryService = new GeometryService("http://tasks.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer");

        esriConfig.defaults.io.proxyUrl = "/proxy/";
        esriConfig.defaults.io.alwaysUseProxy = false;
  
        arcgisUtils.createMap(webmapId, "map").then(function (response) {
        map = response.map;
         initToolbar(map);
        });
       
       //Setup button click handlers
        on(dom.byId("clearGraphics"), "click", function(){
          if(map){
            map.graphics.clear();
          }
        });
        //click handler for the draw tool buttons
        query(".tool").on("click", function(evt){
          if(tb){
           tb.activate(evt.target.id);
          }
        });
        

      function initToolbar(mapObj) {
        tb = new Draw(mapObj);
        tb.on("draw-end", doBuffer);
      }

      function doBuffer(evtObj) {
        tb.deactivate();
        var geometry = evtObj.geometry, symbol;
        switch (geometry.type) {
           case "point":
             symbol = new SimpleMarkerSymbol(SimpleMarkerSymbol.STYLE_SQUARE, 10, new SimpleLineSymbol(SimpleLineSymbol.STYLE_SOLID, new Color([255,0,0]), 1), new Color([0,255,0,0.25]));
             break;
           case "polyline":
             symbol = new SimpleLineSymbol(SimpleLineSymbol.STYLE_DASH, new Color([255,0,0]), 1);
             break;
           case "polygon":
             symbol = new SimpleFillSymbol(SimpleFillSymbol.STYLE_NONE, new SimpleLineSymbol(SimpleLineSymbol.STYLE_DASHDOT, new Color([255,0,0]), 2), new Color([255,255,0,0.25]));
             break;
        }

          var graphic = new Graphic(geometry, symbol);
          map.graphics.add(graphic);

          //setup the buffer parameters
          var params = new BufferParameters();
          params.distances = [ dom.byId("distance").value ];
          params.outSpatialReference = map.spatialReference;
          params.unit = GeometryService[dom.byId("unit").value];
          //normalize the geometry 

          normalizeUtils.normalizeCentralMeridian([geometry]).then(function(normalizedGeometries){
            var normalizedGeometry = normalizedGeometries[0];
            if (normalizedGeometry.type === "polygon") {
              //if geometry is a polygon then simplify polygon.  This will make the user drawn polygon topologically correct.
              esriConfig.defaults.geometryService.simplify([normalizedGeometry], function(geometries) {
                params.geometries = geometries;
                esriConfig.defaults.geometryService.buffer(params, showBuffer);
              });
            } else {
              params.geometries = [normalizedGeometry];
              esriConfig.defaults.geometryService.buffer(params, showBuffer);
            }

          });
        }

        function showBuffer(bufferedGeometries) {
          var symbol = new SimpleFillSymbol(
            SimpleFillSymbol.STYLE_SOLID,
            new SimpleLineSymbol(
              SimpleLineSymbol.STYLE_SOLID,
              new Color([255,0,0,0.65]), 2
            ),
            new Color([255,0,0,0.35])
          );

          array.forEach(bufferedGeometries, function(geometry) {
            var graphic = new Graphic(geometry, symbol);
            map.graphics.add(graphic);
          });

        }
  });
</script>

</head>

<body class="claro">
<div data-dojo-type="dijit/layout/BorderContainer" 
     data-dojo-props="gutters:'true', design:'sidebar'" 
     style="width:100%;height:100%;">

  <div id="map" 
       data-dojo-type="dijit/layout/ContentPane" 
       data-dojo-props="region:'center'">
  </div>

  <div id="leftPane" 
       data-dojo-type="dijit/layout/ContentPane" 
       data-dojo-props="region:'left'">
    <div class="details">Pick a tool and draw on the map. The drawn graphic will be buffered based on the specified parameters.</div>
    <button type="button" class="tool" id="line">Line</button>
    <button type="button" class="tool" id="polyline">Polyline</button>
    <button type="button" class="tool" id="freehandpolyline">Freehand Polyline</button>
    <br/>
    <button type="button" class="tool" id="polygon">Polygon</button>
    <button type="button" class="tool" id="freehandpolygon">Freehand Polygon</button>
    <br/><hr />
    <div><b>Buffer Parameters</b></div>
    Distance:&nbsp;<input type="text" id="distance" size="5" value="25" />
    <select id="unit" style="width:100px;">
      <option value="UNIT_STATUTE_MILE">Miles</option>
      <option value="UNIT_FOOT">Feet</option>
      <option value="UNIT_KILOMETER">Kilometers</option>
      <option value="UNIT_METER">Meters</option>
      <option value="UNIT_NAUTICAL_MILE">Nautical Miles</option>
      <option value="UNIT_US_NAUTICAL_MILE">US Nautical Miles</option>
      <option value="UNIT_DEGREE">Degrees</option>
    </select><br />
    <button type="button" id="clearGraphics"  type="button">Clear Graphics</button>
  </div>
</div>
</body>
</html>