Question

我正在尝试自定义此示例：

http://openlayers.org/en/latest/examples/feature-move-animation.html

var strGeoJson = '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{},"geometry":{"type":"LineString","coordinates":[[25.094146728515625,57.51877294160811],[25.135345458984375,57.55857562213471],[25.11749267578125,57.583614274541404],[25.022735595703125,57.58508660014084],[25.017242431640625,57.633639928856965],[25.11199951171875,57.655688188735766],[25.081787109374996,57.69240553526455],[24.97055053710937,57.68873547372526]]}}]}';

var route =  (
    new ol.format.Polyline({
        factor: 1e6
    }).readFeatures(
        strGeoJson,
        {
            dataProjection: 'EPSG:4326',
            featureProjection: 'EPSG:3857'
        }
    )
);


var routeFeature = new ol.Feature({
    type: 'route',
    geometry: route
});

vectorLayerSource = new ol.source.Vector({
    features: [routeFeature]
});

但是所有的时间：

ol.js?20180608153258:47 Uncaught TypeError: a.addEventListener is not a function
    at y (ol.js?20180608153258:47)
    at Hk.k.Oe (ol.js?20180608153258:302)
    at Hk.b (ol.js?20180608153258:46)
    at Hk.Sc.b (ol.js?20180608153258:49)
    at Yc (ol.js?20180608153258:51)
    at Hk.k.set (ol.js?20180608153258:51)
    at Hk.k.H (ol.js?20180608153258:52)
    at new Hk (ol.js?20180608153258:301)
    at HTMLDocument.<anonymous> (history-map:1372)
    at i (jquery-2.2.3.min.js:2)
    at Object.fireWith [as resolveWith] (jquery-2.2.3.min.js:2)
    at Function.ready (jquery-2.2.3.min.js:2)
    at HTMLDocument.J (jquery-2.2.3.min.js:2)

有人能说出问题出在哪里吗？如何从geojson画一条线。

Answer 1

您的主要问题是您使用的是ol.format.Polyline，而您应该使用ol.format.GeoJSON。

提示是关于以下代码

var route = /** @type {ol.geom.LineString} */ (new ol.format.GeoJSON().readFeature(JSON.parse(strGeoJson).features[0], {
  dataProjection: 'EPSG:4326',
  featureProjection: 'EPSG:3857'
})).getGeometry();

JSON.parse(strGeoJson).features[0]为您提供GeoJSON功能。然后你解析它，然后从中得到ol.geom.LineString（getGeometry()）

您可以在代码中看到a working solution（我已经更改了中心以适合您的样本以及使用OpenStreetMap而不是Bing的背景地图）

从geojson中绘制openlayers折线

1 个答案: