问力更新多次:Gps定位在3-6秒内。

EN

try{gps_enabled=lm.isProviderEnabled(LocationManager.GPS_PROVIDER);}catch(Exception ex){}
                try{network_enabled=lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);}catch(Exception ex){}

 lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 2000, 0, locationListenerGps);

package Hartford.gps;

import java.math.BigDecimal;

import android.app.Activity;
import android.content.Context;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.TextView;

public class GPSMain extends Activity implements LocationListener {

LocationManager locationManager;
LocationListener locationListener;

//text views to display latitude and longitude
TextView latituteField;
TextView longitudeField;
TextView currentSpeedField;
TextView kmphSpeedField;
TextView avgSpeedField;
TextView avgKmphField;

//objects to store positional information
protected double lat;
protected double lon;

//objects to store values for current and average speed
protected double currentSpeed;
protected double kmphSpeed;
protected double avgSpeed;
protected double avgKmph;
protected double totalSpeed;
protected double totalKmph;

//counter that is incremented every time a new position is received, used to calculate average speed
int counter = 0;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    run();
}

@Override
public void onResume() {
    locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 1, this);
    super.onResume();
}

@Override
public void onPause() {
    locationManager.removeUpdates(this);
    super.onPause();
}

private void run(){

    final Criteria criteria = new Criteria();

    criteria.setAccuracy(Criteria.ACCURACY_FINE);
    criteria.setSpeedRequired(true);
    criteria.setAltitudeRequired(false);
    criteria.setBearingRequired(false);
    criteria.setCostAllowed(true);
    criteria.setPowerRequirement(Criteria.POWER_LOW);
    //Acquire a reference to the system Location Manager

    locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);

    // Define a listener that responds to location updates
    locationListener = new LocationListener() {

        public void onLocationChanged(Location newLocation) {

            counter++;

            //current speed fo the gps device
            currentSpeed = round(newLocation.getSpeed(),3,BigDecimal.ROUND_HALF_UP);
            kmphSpeed = round((currentSpeed*3.6),3,BigDecimal.ROUND_HALF_UP);

            //all speeds added together
            totalSpeed = totalSpeed + currentSpeed;
            totalKmph = totalKmph + kmphSpeed;

            //calculates average speed
            avgSpeed = round(totalSpeed/counter,3,BigDecimal.ROUND_HALF_UP);
            avgKmph = round(totalKmph/counter,3,BigDecimal.ROUND_HALF_UP);

            //gets position
            lat = round(((double) (newLocation.getLatitude())),3,BigDecimal.ROUND_HALF_UP);
            lon = round(((double) (newLocation.getLongitude())),3,BigDecimal.ROUND_HALF_UP);

            latituteField = (TextView) findViewById(R.id.lat);
            longitudeField = (TextView) findViewById(R.id.lon);             
            currentSpeedField = (TextView) findViewById(R.id.speed);
            kmphSpeedField = (TextView) findViewById(R.id.kmph);
            avgSpeedField = (TextView) findViewById(R.id.avgspeed);
            avgKmphField = (TextView) findViewById(R.id.avgkmph);

            latituteField.setText("Current Latitude:        "+String.valueOf(lat));
            longitudeField.setText("Current Longitude:      "+String.valueOf(lon));
            currentSpeedField.setText("Current Speed (m/s):     "+String.valueOf(currentSpeed));
            kmphSpeedField.setText("Cuttent Speed (kmph):       "+String.valueOf(kmphSpeed));
            avgSpeedField.setText("Average Speed (m/s):     "+String.valueOf(avgSpeed));
            avgKmphField.setText("Average Speed (kmph):     "+String.valueOf(avgKmph));

        }

        //not entirely sure what these do yet
        public void onStatusChanged(String provider, int status, Bundle extras) {}
        public void onProviderEnabled(String provider) {}
        public void onProviderDisabled(String provider) {}

    };

    // Register the listener with the Location Manager to receive location updates
    locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 1, locationListener);
}

//Method to round the doubles to a max of 3 decimal places
public static double round(double unrounded, int precision, int roundingMode)
{
    BigDecimal bd = new BigDecimal(unrounded);
    BigDecimal rounded = bd.setScale(precision, roundingMode);
    return rounded.doubleValue();
}


@Override
public void onLocationChanged(Location location) {
    // TODO Auto-generated method stub

}

@Override
public void onProviderDisabled(String provider) {
    // TODO Auto-generated method stub

}

@Override
public void onProviderEnabled(String provider) {
    // TODO Auto-generated method stub

}

@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
    // TODO Auto-generated method stub

}

}

public void requestLocationUpdates (String provider, long minTime, float minDistance, LocationListener listener, Looper looper)