Speed warnings

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The SDK provides features for monitoring and notifying users about speed limits and violations. You can configure alerts for when a user exceeds the speed limit, when the speed limit changes on the new road segment with respect to the previous, and when the user returns to a normal speed range (onNormalSpeed). The SDK also allows you to set customizable thresholds for speed violations, which can be adjusted for both city and non-city areas. These features help provide timely and relevant speed-related notifications based on the user's location and current speed.

Configure the 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 will continuously send notifications while the user exceeds with a given threshold the maximum speed limit for the current road section. The onSpeedLimit will be triggered once the current road section has a different speed than the previous road section. The onNormalSpeed will be triggered once the user speed becomes within the limit of the maximum speed limit for the current road section.

note

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.

Set the threshold for speed

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 the threshold for the speed

The configured threshold can be accessed as follows:

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