Vector Layer

Copy

index.html<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Vector Layer</title>
    <!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
    <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL"></script>
    <style>
      .map {
        width: 100%;
        height:400px;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"></div>
    <div id="info">&nbsp;</div>
    <script src="index.js"></script>
  </body>
</html>

Copy

index.jsimport 'ol/ol.css';
import Map from 'ol/Map';
import View from 'ol/View';
import GeoJSON from 'ol/format/GeoJSON';
import VectorLayer from 'ol/layer/Vector';
import VectorSource from 'ol/source/Vector';
import {Fill, Stroke, Style, Text} from 'ol/style';


var style = new Style({
  fill: new Fill({
    color: 'rgba(255, 255, 255, 0.6)'
  }),
  stroke: new Stroke({
    color: '#319FD3',
    width: 1
  }),
  text: new Text({
    font: '12px Calibri,sans-serif',
    fill: new Fill({
      color: '#000'
    }),
    stroke: new Stroke({
      color: '#fff',
      width: 3
    })
  })
});

var vectorLayer = new VectorLayer({
  source: new VectorSource({
    url: 'data/geojson/countries.geojson',
    format: new GeoJSON()
  }),
  style: function(feature) {
    style.getText().setText(feature.get('name'));
    return style;
  }
});

var map = new Map({
  layers: [vectorLayer],
  target: 'map',
  view: new View({
    center: [0, 0],
    zoom: 1
  })
});

var highlightStyle = new Style({
  stroke: new Stroke({
    color: '#f00',
    width: 1
  }),
  fill: new Fill({
    color: 'rgba(255,0,0,0.1)'
  }),
  text: new Text({
    font: '12px Calibri,sans-serif',
    fill: new Fill({
      color: '#000'
    }),
    stroke: new Stroke({
      color: '#f00',
      width: 3
    })
  })
});

var featureOverlay = new VectorLayer({
  source: new VectorSource(),
  map: map,
  style: function(feature) {
    highlightStyle.getText().setText(feature.get('name'));
    return highlightStyle;
  }
});

var highlight;
var displayFeatureInfo = function(pixel) {

  var feature = map.forEachFeatureAtPixel(pixel, function(feature) {
    return feature;
  });

  var info = document.getElementById('info');
  if (feature) {
    info.innerHTML = feature.getId() + ': ' + feature.get('name');
  } else {
    info.innerHTML = '&nbsp;';
  }

  if (feature !== highlight) {
    if (highlight) {
      featureOverlay.getSource().removeFeature(highlight);
    }
    if (feature) {
      featureOverlay.getSource().addFeature(feature);
    }
    highlight = feature;
  }

};

map.on('pointermove', function(evt) {
  if (evt.dragging) {
    return;
  }
  var pixel = map.getEventPixel(evt.originalEvent);
  displayFeatureInfo(pixel);
});

map.on('click', function(evt) {
  displayFeatureInfo(evt.pixel);
});

Copy

package.json{
  "name": "vector-layer",
  "dependencies": {
    "ol": "6.1.1"
  },
  "devDependencies": {
    "parcel": "1.11.0"
  },
  "scripts": {
    "start": "parcel index.html",
    "build": "parcel build --experimental-scope-hoisting --public-url . index.html"
  }
}