Do not change map center or zoom level when render

问题:

I want to have a large map of berlin from which you see multiple routes. Unfortunately a DirectionsRenderer zooms to the route so you have to manually zoom out again.

How do I avoid this behavior?

var $canvas = document.querySelector('#map');

var map = new google.maps.Map($canvas, {
    center: new google.maps.LatLng(52.46004869999999, 13.37898690),
    mapTypeId: google.maps.MapTypeId.ROADMAP,
    zoom: 14
});

var routes = [
    { 
        origin: new google.maps.LatLng(52.459281, 13.356367),
        destination: new google.maps.LatLng(52.455833, 13.322948),
        travelMode: google.maps.TravelMode.BICYCLING
    },
    {
        origin: new google.maps.LatLng(52.597621, 13.430536),
        destination: new google.maps.LatLng(52.5918799, 13.2832929),
        travelMode: google.maps.TravelMode.BICYCLING
    }
];

routes.forEach(function(route) {
    new google.maps.DirectionsService().route(route, function(body) {
        var display = new google.maps.DirectionsRenderer();

        display.setMap(map);
        display.setDirections(body);
    });
});

http://jsfiddle.net/H3GE3/2/

回答1:

Use the preserveViewport option of the DirectionsRenderer to prevent the automatic zoom to the route, then set the viewport you like.

{preserveViewport: true}

Or if you want, calculate the union of the bounds of the directions responses, and fit the map to that.

var bounds = new google.maps.LatLngBounds();
routes.forEach(function(route) {
    new google.maps.DirectionsService().route(route, function(body) {
        var display = new google.maps.DirectionsRenderer({preserveViewport: true});

        display.setMap(map);
        display.setDirections(body);
        bounds.union(body.routes[0].bounds);
        map.fitBounds(bounds);
    });
});

proof of concept fiddle

code snippet:

var $canvas = document.querySelector('#map');

var map = new google.maps.Map($canvas, {
  center: new google.maps.LatLng(52.46004869999999, 13.37898690),
  mapTypeId: google.maps.MapTypeId.ROADMAP,
  zoom: 14
});

var routes = [{
    origin: new google.maps.LatLng(52.459281, 13.356367),
    destination: new google.maps.LatLng(52.455833, 13.322948),
    travelMode: google.maps.TravelMode.BICYCLING
  },
  {
    origin: new google.maps.LatLng(52.597621, 13.430536),
    destination: new google.maps.LatLng(52.5918799, 13.2832929),
    travelMode: google.maps.TravelMode.BICYCLING
  }
];
var bounds = new google.maps.LatLngBounds();
routes.forEach(function(route) {
  new google.maps.DirectionsService().route(route, function(body) {
    var display = new google.maps.DirectionsRenderer({
      preserveViewport: true
    });

    display.setMap(map);
    display.setDirections(body);
    bounds.union(body.routes[0].bounds);
    map.fitBounds(bounds);
  });
});

html,
body,
div#map {
  height: 100%;
  width: 100%;
  padding: 0px;
  margin: 0px;
}

<div id="map"></div>
<script src="https://maps.googleapis.com/maps/api/js"></script>