it there an Android event lister for speed?

I have an app for speed measuring and would to detect when a user goes above or below certa开发者_运维百科in speed. Do I have to constantly monitor the speed or there an event I can create?

You need to monitor for location changes, and when you get an alarm of it, you need to check if the current location hasSpeed()

/**
 *
 */
private void requestUpdates() {
    locMan = (LocationManager) getSystemService(Context.LOCATION_SERVICE);

    // loop through all providers, and register them to send updates
    List<String> providers = locMan.getProviders(false);
    for (String provider : providers) {
        Log.e("birthdroid", "registering provider " + provider);
        long minTimeMs = 5 * 60 * 1000;// 5 minute interval
        float minDistance = Application.LOCATION_HOT_RADIUS_IN_METERS;
        locMan.requestLocationUpdates(provider, minTimeMs, minDistance,
                getIntent());
    }

}

/**
 * convenient method to get pending intent
 * @return
 */
private PendingIntent getIntent() {
    Intent intent = new Intent(this, LocationReceiver.class);
    return PendingIntent.getBroadcast(
            getApplicationContext(), 0, intent, 0);
}

and the Receiver can be

public class LocationReceiver extends BroadcastReceiver {

    /*
     * (non-Javadoc)
     * 
     * @see android.content.BroadcastReceiver#onReceive(android.content.Context,
     * android.content.Intent)
     */
    @Override
    public void onReceive(Context context, Intent intent) {
        try {
            Bundle b = intent.getExtras();
            Location loc = (Location) b
                    .get(android.location.LocationManager.KEY_LOCATION_CHANGED);
            if (loc != null) {


            }

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

There is no event for speed, you'd have to calculate it and sound an "alarm" whenever the speed is above the threshold.