Allow Non-Stopover Waypoints

[pcoughran]

From https://developers.google.com/maps/documentation/directions/ -->

You can use waypoints to influence your route without adding a stopover by prefixing the waypoint with via:. Waypoints prefixed with via: will not add an additional leg to the route.

Sample Request:

https://maps.googleapis.com/maps/api/directions/json?origin=Boston,MA&destination=Concord,MA&waypoints=Charlestown,MA|via:Lexington,MA&key=API_KEY

[markmcd]

Thanks for the FR. I'm not going to be able to get to this in the next couple of weeks but if anyone else wants to send a pull request through I'd be happy to take a look at it.

[domesticmouse]

@pcoughran could you propose an API interface that would make sense for this use case? I have done a bit thinking of how best to expose this in the API, but would love your thoughts. Thank you!

[gardster]

Javascript API has stopover property to set up a waypoint type. Maybe implement this feature with the same way?

[raulastu]

how do I set up stopover=false in the sample request? I would like duration_in_traffic to be returned in every leg, and via: prefix does not add a leg entry.

[apjanke]

How about this: We currently have String and LatLng waypoint variants in DirectionsApiRequest.

public DirectionsApiRequest waypoints(LatLng... waypoints)
public DirectionsApiRequest waypoints(String... waypoints)

We could add a Waypoint class, and a public DirectionsApiRequest waypoints(Waypoint... waypoints) method. The Waypoint class could have a boolean isStopover flag that defaults to false, and constructors:

Waypoint(String str)
Waypoint(String str, boolean isStopover)
Waypoint(LatLng point)
Waypoint(LatLng point, boolean isStopover)

The DirectionsApiRequest's internal waypoints field could either be converted to Waypoint[], or it could remain String[], and the Waypoint objects converted to String in the waypoints(Waypoint...) method. (I like the former.)

[domesticmouse]

I like your proposal @apjanke. Feel free to put together a PR for your preferred approach if you have time, otherwise I'll loop back and implement when I get a spare moment. Thanks!

[apjanke]

Here's a PR: #468. I made Waypoint a nested class in DirectionsApiRequest, since that seems consistent with the existing design.

NOTE: In my design, the isStopover flag defaults to true, instead of false like I said previously. I misspoke: it should default to true, I think, since that's the current default behavior for String and LatLng waypoint arguments.