Removing Polylines

This example adds a UI control that allows the user to remove the polyline from the map.

Read the documentation.

TypeScript

// This example adds a UI control allowing users to remove the polyline from the
// map.

let flightPath: google.maps.Polyline;
let map: google.maps.Map;

function initMap(): void {
  map = new google.maps.Map(document.getElementById("map") as HTMLElement, {
    zoom: 3,
    center: { lat: 0, lng: -180 },
    mapTypeId: "terrain",
  });

  const flightPathCoordinates: google.maps.LatLngLiteral[] = [
    { lat: 37.772, lng: -122.214 },
    { lat: 21.291, lng: -157.821 },
    { lat: -18.142, lng: 178.431 },
    { lat: -27.467, lng: 153.027 },
  ];

  flightPath = new google.maps.Polyline({
    path: flightPathCoordinates,
    strokeColor: "#FF0000",
    strokeOpacity: 1.0,
    strokeWeight: 2,
  });

  // add event listener for click event
  document.getElementById("add-line")!.addEventListener("click", addLine);
  document.getElementById("remove-line")!.addEventListener("click", removeLine);

  // initialize with line
  addLine();
}

function addLine(): void {
  flightPath.setMap(map);
}

function removeLine(): void {
  flightPath.setMap(null);
}

declare global {
  interface Window {
    initMap: () => void;
  }
}
window.initMap = initMap;
index.ts

JavaScript

// This example adds a UI control allowing users to remove the polyline from the
// map.
let flightPath;
let map;

function initMap() {
  map = new google.maps.Map(document.getElementById("map"), {
    zoom: 3,
    center: { lat: 0, lng: -180 },
    mapTypeId: "terrain",
  });

  const flightPathCoordinates = [
    { lat: 37.772, lng: -122.214 },
    { lat: 21.291, lng: -157.821 },
    { lat: -18.142, lng: 178.431 },
    { lat: -27.467, lng: 153.027 },
  ];

  flightPath = new google.maps.Polyline({
    path: flightPathCoordinates,
    strokeColor: "#FF0000",
    strokeOpacity: 1.0,
    strokeWeight: 2,
  });
  // add event listener for click event
  document.getElementById("add-line").addEventListener("click", addLine);
  document.getElementById("remove-line").addEventListener("click", removeLine);
  // initialize with line
  addLine();
}

function addLine() {
  flightPath.setMap(map);
}

function removeLine() {
  flightPath.setMap(null);
}

window.initMap = initMap;
index.js

CSS

/* 
 * Always set the map height explicitly to define the size of the div element
 * that contains the map. 
 */
#map {
  height: 100%;
}

/* 
 * Optional: Makes the sample page fill the window. 
 */
html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
}

#floating-panel {
  position: absolute;
  top: 10px;
  left: 25%;
  z-index: 5;
  background-color: #fff;
  padding: 5px;
  border: 1px solid #999;
  text-align: center;
  font-family: "Roboto", "sans-serif";
  line-height: 30px;
  padding-left: 10px;
}

style.css

HTML

<html>
  <head>
    <title>Removing Polylines</title>

    <link rel="stylesheet" type="text/css" href="./style.css" />
    <script type="module" src="./index.js"></script>
  </head>
  <body>
    <div id="floating-panel">
      <input id="remove-line" type="button" value="Remove line" />
      <input id="add-line" type="button" value="Restore line" />
    </div>
    <div id="map"></div>

    <!-- 
      The `defer` attribute causes the script to execute after the full HTML
      document has been parsed. For non-blocking uses, avoiding race conditions,
      and consistent behavior across browsers, consider loading using Promises. See
      https://developers.google.com/maps/documentation/javascript/load-maps-js-api
      for more information.
      -->
    <script
      src="https://maps.googleapis.com/maps/api/js?key=AIzaSyB41DRUbKWJHPxaFjMAwdrzWzbVKartNGg&callback=initMap&v=weekly"
      defer
    ></script>
  </body>
</html>
index.html

Try Sample

Clone Sample

Git and Node.js are required to run this sample locally. Follow these instructions to install Node.js and NPM. The following commands clone, install dependencies and start the sample application. 

  git clone -b sample-polyline-remove https://github.com/googlemaps/js-samples.git
  cd js-samples
  npm i
  npm start

Other samples can be tried by switching to any branch beginning with sample-SAMPLE_NAME. 

  git checkout sample-SAMPLE_NAME
  npm i
  npm start