Skip to main content
GuidesAPI ReferenceExamplesFAQ

Speed warnings

|

This guide explains how to configure speed limit monitoring and receive notifications about speed violations and speed limit changes.

The SDK monitors and notifies you about speed limits and violations. You can configure alerts for when a user exceeds the speed limit, when the speed limit changes on a new road segment, and when the user returns to a normal speed range. You can set customizable thresholds for speed violations, which can be adjusted for both city and non-city areas. These features provide timely speed-related notifications based on the user's location and current speed.

Configure speed limit listeners​

AlarmListener alarmListener = AlarmListener(
    onHighSpeed: (limit, insideCityArea) {
        if (insideCityArea) {
            showSnackbar("Speed limit exceeded while inside city area - limit is $limit m/s");
        } else {
            showSnackbar("Speed limit exceeded while outside city area - limit is $limit m/s");
        }
    },
    onSpeedLimit: (speed, limit, insideCityArea) {
        if (insideCityArea) {
            showSnackbar("New speed limit updated to $limit m/s while inside city area. The current speed is $speed m/s");
        } else {
            showSnackbar("New speed limit updated to $limit m/s while outside city area. The current speed is $speed m/s");
        }
    },
    onNormalSpeed: (limit, insideCityArea) {
        if (insideCityArea) {
            showSnackbar("Normal speed restored while inside city area - limit is $limit m/s");
        } else {
            showSnackbar("Normal speed restored while outside city area - limit is $limit m/s");
        }
    },
);

// Create alarm service based on the previously created listener
AlarmService alarmService = AlarmService(alarmListener);

The onHighSpeed callback continuously sends notifications while the user exceeds the maximum speed limit for the current road section by a given threshold.

The onSpeedLimit callback is triggered when the current road section has a different speed limit than the previous road section.

The onNormalSpeed callback is triggered when the user speed returns within the limit of the maximum speed limit for the current road section.

info

Although the parameter is named insideCityArea, it refers to areas with generally lower speed limits, such as cities, towns, villages, or similar settlements, regardless of their classification.

warning

The limit parameter provided to onSpeedLimit will be 0 if the matched road section does not have a maximum speed limit available or if no road could be found.

Set speed threshold​

The threshold for the maximum speed excess that triggers the onHighSpeed callback can be configured as follows:

// Trigger onHighSpeed when the speed limit is exceeded by 1 m/s inside a city area
alarmService.setOverSpeedThreshold(threshold: 1, insideCityArea: true);    
// Trigger onHighSpeed when the speed limit is exceeded by 3 m/s inside a city area
alarmService.setOverSpeedThreshold(threshold: 3, insideCityArea: true);

Get speed threshold​

To access the configured threshold:

double currentThresholdInsideCity = alarmService.getOverSpeedThreshold(true);
double currentThresholdOutsideCity = alarmService.getOverSpeedThreshold(false);
Last updated on