CODEWITHSUNDEEP
javascriptgoogle-mapsgoogle-maps-api-3
Carlos Valencia
Carlos Valencia

Reputation: 7003

Google Maps Api - Do not change map center on Zoom

Is it possible to keep the same map center on the zoom in/out events? whether it is with the scroll wheel, double clicking or with the zoom controls it should behave the same.

I've noticed there is a bias towards the mouse pointer position on the map when zooming in/out with the Scroll Wheel, I haven't found any options on the Docs, but overriding that bias would be ideal.

here is a simple fiddle of how i am initializing my map.

var map = new google.maps.Map(document.getElementById("map_div"), {
    center: new google.maps.LatLng(33.808678, -117.918921),
    zoom: 15,
    disableDefaultUI: true
  });

Upvotes: 1

Views: 1367

Answers (1)

Carlos Valencia
Carlos Valencia

Reputation: 7003

Following @Adam's suggestion on the comments, I disabled the scroll wheel zoom, plus the double click zoom when instantiating the map and added event listeners to handle those events with my own implementation.

Here is a working fiddle and the code explained:

/*
 * declare map as a global variable
 */
var map;
/*
 * use google maps api built-in mechanism to attach dom events
 */
google.maps.event.addDomListener(window, "load", function() {
  var myMap = document.getElementById("map_div");
  /*
   * create map
   */
  var map = new google.maps.Map(myMap, {
    center: new google.maps.LatLng(33.808678, -117.918921),
    zoom: 15,
    disableDefaultUI: true,
    scrollwheel: false,
    disableDoubleClickZoom: true
  });
    //function that will handle the wheelEvent
  function wheelEvent(event) {
    var e = window.event || e; // old IE support
    var delta = Math.max(-1, Math.min(1, (e.wheelDelta || -e.detail))); //to know whether it was wheel up or down
    map.setZoom(map.getZoom() + delta);
  }

  function zoomIn() {
    map.setZoom(map.getZoom() + 1);
  }

  //add a normal event listener on the map container
  myMap.addEventListener('mousewheel', wheelEvent, true);
  myMap.addEventListener('DOMMouseScroll', wheelEvent, true);

  //same with the double click
  myMap.addEventListener('dblclick', zoomIn, true);

  //add center changed listener for testing
  google.maps.event.addListener(map, 'center_changed', function() {
    console.log("this is what i'm trying to avoid");
  });
});

Upvotes: 5

Related Questions