Question

尝试将地图缩放到某个点时，我遇到了一些问题。以下是我使用Esri基本地图设置地图的方法，其中包含OneMap地图叠加层：

function setMap() {
function init() {
    require(
        [
            "esri/map",
            "dojo/dom-construct",
            "esri/geometry/Point", 
            "esri/symbols/SimpleMarkerSymbol", "esri/symbols/SimpleLineSymbol",
            "esri/graphic", "esri/Color","esri/tasks/ProjectParameters",
            "dojo/domReady!"
        ],
        function 
        (
            Map, domConstruct, Point,
            SimpleMarkerSymbol, SimpleLineSymbol,
            Graphic, Color,ProjectParameters
        ) {
            map = Map("map-canvas",
            {
            });
            map.setZoom(0);
            coreFunctions();
        });
    // Get current location
    map.on("load", getCurrentLoc);
}
dojo.ready(init);
gsvc = new esri.tasks.GeometryService("http://tasks.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer");
}

我添加了一个叠加层：

function addLayersToData() {
    var layer = new esri.layers.ArcGISTiledMapServiceLayer("https://www.onemap.sg/ArcGIS/rest/services/BASEMAP/MapServer");
    mapLayers.push(layer);
}

我的方法是将地图设置为缩放到某个点：

function zoomPostal(postalCode) {
 $.getJSON("http://www.onemap.sg/API/services.svc/basicSearch?token=qo/s2TnSUmfLz+32CvLC4RMVkzEFYjxqyti1KhByvEacEdMWBpCuSSQ+IFRT84QjGPBCuz/cBom8PfSm3GjEsGc8PkdEEOEr&searchVal="
                        + postalCode
                        + "&otptFlds=SEARCHVAL,CATEGORY&returnGeom=0&rset=1", function (data) {

    esriConfig.defaults.geometryService = new esri.tasks.GeometryService("http://tasks.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer");
    var loc = new esri.geometry.Point({ "x": data.SearchResults[1].X, "y": data.SearchResults[1].Y, "spatialReference": { "wkid": 3414 } });           

    var params = new esri.tasks.ProjectParameters();
    params.geometries = [loc.geometry];
    params.outSR = map.spatialReference;
    esri.config.defaults.geometryService.project(params, function (loc) {
        map.centerAndZoom(loc[0],12);
    });

    });
}

到目前为止，我知道使用setZoom将地图缩放到某个级别，但我不知道如何将其缩放到某个点。有任何想法吗？

提前致谢。

Answer 1

正确的方法是使用sebastian建议的centerAndZoom（mapPoint，levelOrFactor）。您得到的错误是几何的空间参考与地图的空间参考不同。因此，只需调用几何服务来首先转换几何体。

https://developers.arcgis.com/javascript/jsapi/geometryservice-amd.html#project

                  require([
                        "esri/tasks/ProjectParameters"
                    ], function (ProjectParameters) {
                        var params = new ProjectParameters();
                        params.geometries = [loc.geometry];
                        params.outSR = map.spatialReference;

                       // params.transformation = transformation;

                            esri.config.defaults.geometryService.project(params, function (projectedPoints) {

                                map.centerAndZoom(projectedPoints[0],levelofyourchoice);

                            });
                    });

如果您没有基准转换，则不需要进行转换。

点击此处：https://developers.arcgis.com/javascript/jsapi/projectparameters-amd.html#transformation

添加此项以实例化几何服务：

require(["esri/tasks/GeometryService"], function(GeometryService) {   esriConfig.defaults.geometryService = new GeometryService("http://tasks.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer");});

Answer 2

答案可能为时已晚，但我找到了适当的方法：

var point = yourPoint;
var offset = 5; // choose your offset for displaying your point
map.setExtent(new esri.geometry.Extent(point.x - offset, point.y - offset, point.x + offset, point.y + offset, new esri.SpatialReference(map.spatialReference));
map.centerAt(point) // it's kind of useless

Esri地图缩放到某个点

2 个答案: