# Better route detection

Last updated:

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October 18, 2026

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\| 3 minutes read

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Monitor traffic conditions and automatically evaluate alternative routes for optimal navigation. This feature provides real-time route adjustments, reducing travel time and improving efficiency in dynamic traffic environments.

## What you need[​](#what-you-need "Direct link to What you need")

info

**Prerequisites:**

* Route computed with specific `RoutePreferences` settings
* Active traffic data on the route
* Significant time gain (over 5 minutes) for alternative routes

## Step 1: Configure route preferences[​](#step-1-configure-route-preferences "Direct link to Step 1: Configure route preferences")

Configure the `RoutePreferences` object with the following required settings:

* `transportMode` - `RouteTransportMode.car` or `RouteTransportMode.lorry`
* `avoidTraffic` - `TrafficAvoidance.all` or `TrafficAvoidance.roadblocks`
* `routeType` - `RouteType.fastest`

```dart
final routePreferences = RoutePreferences(
  routeType: RouteType.fastest,
  avoidTraffic: TrafficAvoidance.roadblocks,
  transportMode: RouteTransportMode.car,
);

```

Add additional settings to `RoutePreferences` during route calculation, provided they don't conflict with the required preferences above.

### Additional requirements[​](#additional-requirements "Direct link to Additional requirements")

**Traffic data:**<br /><!-- -->Traffic must be present on the active navigation route for callbacks to trigger.

**Time savings threshold:**<br /><!-- -->Alternative routes must offer time savings exceeding five minutes to be considered. This ensures meaningful route adjustments.

warning

❌ Better route detection will not function if the required conditions above are not met.

## Step 2: Register notification callbacks[​](#step-2-register-notification-callbacks "Direct link to Step 2: Register notification callbacks")

Register callbacks using `startSimulation` or `startNavigation` methods from the `NavigationService` class:

* **`onBetterRouteDetected`** - triggered when a better route is identified. Provides the new route, total travel time, traffic-induced delay, and time savings compared to the current route.
* **`onBetterRouteInvalidated`** - triggered when a previously detected better route is no longer valid. Occurs if the user deviates from the shared trunk, a better alternative appears, or traffic conditions change.
* **`onBetterRouteRejected`** - triggered when no suitable alternative route is found during the check.

info

You must manually manage and switch to the recommended route. The navigation service does not automatically switch routes.

```dart
NavigationService.startSimulation(
  route,
  onBetterRouteDetected: (route, travelTime, delay, timeGain) {
    print("Better route detected - travel time: $travelTime s, delay: $delay s, time gain: $timeGain s");
    // Handle the route
  },
  onBetterRouteInvalidated: () {
    print("Previously found better route is no longer valid");
  },
  onBetterRouteRejected: (reason) {
    print("Better route check failed: $reason");
  },
);

```

## Step 3: Trigger manual checks (optional)[​](#step-3-trigger-manual-checks-optional "Direct link to Step 3: Trigger manual checks (optional)")

The system automatically checks for better routes at predefined intervals when all conditions are met.

Manually trigger a check using the `checkBetterRoute` static method from the `Debug` class. The `onBetterRouteDetected` callback is invoked if a better route is found; otherwise, `onBetterRouteRejected` is triggered if no suitable alternative exists.

```dart
Debug.checkBetterRoute();

```

## Relevant examples demonstrating better route features[​](#relevant-examples-demonstrating-better-route-features "Direct link to Relevant examples demonstrating better route features")

* [Better Route Notification](/docs/flutter/examples/routing-navigation/better-route-notification.md)