• JavaScript
  • HTML
                  
                  
/**
 * Restricts a moveable map to a given rectangle.
 *
 * @param {H.Map} map   A HERE Map instance within the application
 *
 */
function restrictMap(map){

  var bounds = new H.geo.Rect(37.829, -122.426, 37.824, -122.42);

  map.getViewModel().addEventListener('sync', function() {
    var center = map.getCenter();

    if (!bounds.containsPoint(center)) {
      if (center.lat > bounds.getTop()) {
        center.lat = bounds.getTop();
      } else if (center.lat < bounds.getBottom()) {
        center.lat = bounds.getBottom();
      }
      if (center.lng < bounds.getLeft()) {
        center.lng = bounds.getLeft();
      } else if (center.lng > bounds.getRight()) {
        center.lng = bounds.getRight();
      }
      map.setCenter(center);
    }
  });

  //Debug code to visualize where your restriction is
  map.addObject(new H.map.Rect(bounds, {
    style: {
        fillColor: 'rgba(55, 85, 170, 0.1)',
        strokeColor: 'rgba(55, 85, 170, 0.6)',
        lineWidth: 8
      }
    }
  ));
}

/**
 * Boilerplate map initialization code starts below:
 */

//Step 1: initialize communication with the platform
var platform = new H.service.Platform({
  app_id: window.app_id,
  app_code: window.app_code,
  useHTTPS: true
});
var pixelRatio = window.devicePixelRatio || 1;
var defaultLayers = platform.createDefaultLayers({
  tileSize: pixelRatio === 1 ? 256 : 512,
  ppi: pixelRatio === 1 ? undefined : 320
});

//Step 2: initialize a map - this map is centered over Alcatraz Island
var map = new H.Map(document.getElementById('map'),
  defaultLayers.normal.map,{
  center: {lat:37.82667, lng:-122.423333},
  zoom: 16,
  pixelRatio: pixelRatio
});
// add a resize listener to make sure that the map occupies the whole container
window.addEventListener('resize', () => map.getViewPort().resize());

map.setBaseLayer(defaultLayers.satellite.map);

//Step 3: make the map interactive
// MapEvents enables the event system
// Behavior implements default interactions for pan/zoom (also on mobile touch environments)
var behavior = new H.mapevents.Behavior(new H.mapevents.MapEvents(map));

// Step 4: Create the default UI:
var ui = H.ui.UI.createDefault(map, defaultLayers, 'en-US');

restrictMap(map);                  
                
                  
                  
<!DOCTYPE html>
<html>
  <head>
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=yes">
    <meta http-equiv="Content-type" content="text/html;charset=UTF-8">
    
    <title>Restrict Map Movement</title>
    <link rel="stylesheet" type="text/css" href="https://js.api.here.com/v3/3.0/mapsjs-ui.css" />
    <link rel="stylesheet" type="text/css" href="demo.css" />
    <link rel="stylesheet" type="text/css" href="styles.css" />
    <link rel="stylesheet" type="text/css" href="../template.css" />
    <script type="text/javascript" src='../test-credentials.js'></script>
    <script type="text/javascript" src="https://js.api.here.com/v3/3.0/mapsjs-core.js"></script>
    <script type="text/javascript" src="https://js.api.here.com/v3/3.0/mapsjs-service.js"></script>
    <script type="text/javascript" src="https://js.api.here.com/v3/3.0/mapsjs-ui.js"></script>
    <script type="text/javascript" src="https://js.api.here.com/v3/3.0/mapsjs-mapevents.js"></script>
  <script type="text/javascript" src='../js-examples-rendering-helpers/iframe-height.js'></script></head>
  <body id="markers-on-the-map">

    <div class="page-header">
        <h1>Restrict Map Movement</h1>
        <p>Restrict a moveable map to a given rectangular area</p>
    </div>
    <p>This example displays a moveable map of <b>Alcatraz Island</b>. Even though the map can still be panned and zoomed, 
      the center of the map cannot be moved outside of the marked area</p>
    <div id="map"></div>
    <h3>Code</h3>
    <p>The <code>H.map.ViewModel</code> represents the position of the map. The <code>sync</code> event is fired whenever 
      the rendered map is synchronized with the view-model data. By listening to the sync event the value of the <code>map.center</code> can be restricted to a certain range.</p>
    <script type="text/javascript" src='demo.js'></script>
  </body>
</html>