Route calculations (including rerouting) return the route that takes the least amount of time to navigate as the default best route. But you can change the routing strategy so that the shorter of the route alternatives is returned instead.
The term shorter means the route that is the shortest among optimal routes based on our default cost model. The shorter route might not be the absolute shortest route, since that option might be a poor alternative. For example, if the absolute shortest route is 10 km and takes 50 minutes to navigate and another route is 15 km, but only takes 20 minutes to navigate, the second choice is optimal, because spending 30 mins to reduce five km isn't a good trade-off.
Once you set the routing strategy for a trip, it won't change until the trip completes. To change the routing strategy for an existing trip, you must clear the destinations and reset them again with the new routing strategy.
Getting route details
To determine which route strategy is the optimal choice for a given
waypoint, call getRouteInfo()
to get route details for both the
default best route and the absolute shorter route. Details include the duration
and the distance to a destination waypoint.
These details come from RouteInfo
, and are returned in a
ListenableResultFuture
.
Example
The following code example demonstrates how to get route details for each of the two routing strategies.
ListenableResultFuture<RouteInfo> routeInfoFuture =
navigator.getRouteInfo(waypoint, routingOptions);
Setting the routing strategy
You can configure the routing strategy by setting
RoutingOptions.routingStrategy
when you call setDestinations()
.
RoutingOptions.routingStrategy
takes one of the following enumeration
values:
Enumeration Value | Description |
---|---|
RoutingStrategy.DEFAULT_BEST | Ranks routes by the Navigation SDK's default cost model. This is the default routing strategy. |
RoutingStrategy.SHORTER | Ranks routes by distance. The highest ranking route is the shortest of those returned. |
Example
The following code example demonstrates how to set the shorter route preference.
RoutingOptions routingOptions = new RoutingOptions();
routingOptions.routingStrategy(RoutingStrategy.SHORTER);
navigator.setDestinations(destinations, routingOptions, displayOptions);
Routes that include ferries
By default, the NavSDK excludes routes that include ferries. If
you prefer to include ferry options as part of your routes, you can adjust
this routing preference to expose the trip to ferry segments by setting
avoidFerries
to false
.
Example
RoutingOptions routingOptions = new RoutingOptions().avoidFerries(true);
// Add additional routing preferences
navigator.setDestination(destination, routingOptions);
The route callout format
Under the shorter route preference, callouts along the route display distance details. But you can use the ETA callouts instead.
Configuring the route callout format
You can change the route callout format by calling setRouteCalloutInfoFormat
in NavigationView
(or in NavigationFragment
). setRouteCalloutInfoFormat
takes one of the following enumeration values:
Enumeration Value | Description |
---|---|
RouteCalloutInfoFormat.DEFAULT | Displays time remaining when using the default best route routing strategy. Displays distance remaining when using the shorter route routing strategy. |
RouteCalloutInfoFormat.TIME | Displays time remaining. |
RouteCalloutInfoFormat.DISTANCE | Displays distance remaining. |
Example
The following code example demonstrates how to configure the route callout format.
mNavFragment.setRouteCalloutInfoFormat(RouteCalloutInfoFormat.TIME);