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Handle Speed Limit Tightened Alert

Handle speed limit tightened alerts

This tutorial shows how to handle speed limit tightened alerts.

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All speed limit tightened alerts are point alerts, representing that the speed limit changes to lower around the alert location.

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void AlertObserver::onAlertInfoUpdated(const tn::drive::models::v1::AlertInfo& alertInfo)
{
    const auto& aheadAlerts = alertInfo.alerts_ahead;
    for (const auto& alert : aheadAlerts.speed_limit_tightened_alerts)
    {
        // following type is speed limit tightened alert:
        // tn::drive::models::v1::AlertType::SpeedLimitTightened
        const auto type = alert.basic.type;

        // each alert item has a unique identifier, can be used to match alert updates
        const auto id = alert.basic.id;

        // current speed limit
        const auto& currentSpeedLimit = alert.camera_info.current_speed_limit;

        // the tightened speed limit ahead
        const auto& tightenedSpeedLimit = alert.camera_info.tightened_speed_limit;

        showSpeedLimitTightenedIconOnMap(id, currentSpeedLimit, tightenedSpeedLimit, alert.point->location);
    }
}