Plotting more than 8 waypoints in Google Maps v3

问题

Migrating code from Javascript API 2 to 3. I have a list of locations which i need to plot in the form of a driving directions. This was done in v2 using the following code

directions = new GDirections(map);
directions.loadFromWaypoints(waypoints, {preserveViewport: true});  

Here is my attempt at converting this to V3

var request = {
    origin: startLoc,
    destination: endLoc,
    waypoints: waypoints,
    optimizeWaypoints: true,
    travelMode: google.maps.TravelMode.DRIVING
};          

directionsService.route(request, function(response, status) {
    if (status == google.maps.DirectionsStatus.OK) {
        directionsDisplay.setDirections(response);
    } 
});

Not the whole code, but the general idea. Seems to work fine, with one little issue. When there are more than 8 waypoints, the call fails. This is expected since Google Maps API v3 Docs states

The maximum allowed waypoints is 8, plus the origin, and destination. Maps API for Business customers are allowed 23 waypoints, plus the origin, and destination. Waypoints are not supported for transit directions.

Since i didn't run in to this issue in v2, is this a new restriction with v3? I wonder if i am using something that was not designed for what i need. This is a very lightly used applicaton with 2 users, so i am not sure if an expensive business license is worth the return. Emails to Google maps team have not yet been returned. Any workarounds/pointers will be of great help. Thanks.

回答1:

One possible work around (particularly for a lightly used site) is to use multiple DirectionsService requests.

• example 1 (addresses)
• example 2 (coordinates)

回答2:

Use Should need to Use array concept like these...

directionsService[i].route({                                    
                    'origin': start,
                    'destination': end
                    'waypoints': waypts,
                    'travelMode': 'DRIVING'
                       },
                    function (directions, status){              
                                if (status == google.maps.DirectionsStatus.OK) {
                                    directionsDisplay[j].setDirections(directions);
                                }
                            });

in these directionservice and directiondisplay are should be in array logic and using looping concepts use should need to assign start,end and waypoints dynamically and
try sending multiple request means u ll get the route for n number of latlon's ...but the markers ll be repeat with same name after 8 waypoints for that we remove the default markers by using supressmarkers false property...

回答3:

As others said, it's imposable to do it using Google's JavaScript API. However, Google does allow up to 23 waypoints with a server-side request. So using PHP and JavaScript, I was able to make a workaround.

What you have to do is get the "waypoint order" from the server side request and then have JavaScript give you directions between each location.

<?php
  $startLocation = "40.713,-74.0135";
  $endLocation = "40.75773,-73.985708";
  $waypoints = array("40.748433,-73.985656|", "40.689167,-74.044444|");
  $apiKey = "";
  $routeData = json_decode(file_get_contents("https://maps.googleapis.com/maps/api/directions/json?origin=".$startLoc."&destination=".$endLoc."&waypoints=optimize:true|".$waypoints."&key=".$apiKey));
  echo "var waypointsOrder = ". json_encode($routeData->routes[0]->waypoint_order) . ";\n";
?>

var startLocation = {lat: 40.713, lng: -74.0135};
var endLocation = {lat: 40.75773, lng: -73.985708};

//get directions from the origin to the first waypoint
var request = {
    origin: startLocation,
    destination: JSON.parse(places[waypointsOrder[0]][1]),
    travelMode: google.maps.TravelMode.DRIVING
};
directionsService.route(request, function (result, status) {
    if (status == google.maps.DirectionsStatus.OK) {
          renderDirections(result, map);
    }
});

//get directions from the last waypoint to the destination
var request = {
    origin: JSON.parse(places[waypointsOrder[waypointsOrder.length-1]][1]),
    destination: endLocation,
    travelMode: google.maps.TravelMode.DRIVING
};
directionsService.route(request, function (result, status) {
    if (status == google.maps.DirectionsStatus.OK) {
          renderDirections(result, map);
    }
});

//get directions between each waypoint
for (i = 1; i < waypointsOrder.length; i++) {
  var request = {
      origin: JSON.parse(places[waypointsOrder[i-1]][1]),
      destination: JSON.parse(places[waypointsOrder[i]][1]),
      travelMode: google.maps.TravelMode.DRIVING
  };
  directionsService.route(request, function (result, status) {
      if (status == google.maps.DirectionsStatus.OK) {
          renderDirections(result, map);
      }
  });
}

function renderDirections(result, map) {
  var directionsDisplay = new google.maps.DirectionsRenderer ({
    map: map
  });
  directionsDisplay.setMap(map); 
  directionsDisplay.setDirections(result); 
}

来源：https://stackoverflow.com/questions/19848826/plotting-more-than-8-waypoints-in-google-maps-v3