错误：MainActivity不是抽象的，并且不会覆盖LocationListener中的抽象方法onLocationChanged（Location）

Question

这是我的MainActivity

    import android.app.Activity;
    import android.app.AlertDialog;
    import android.app.ProgressDialog;
    import android.content.Context;
    import android.content.DialogInterface;
    import android.content.Intent;
    import android.location.Location;
    import android.location.LocationManager;
    import android.os.Bundle;
    import android.util.Log;
    import android.view.MotionEvent;
    import android.view.View;
    import android.widget.TextView;
    import android.widget.Toast;

    import com.google.android.gms.location.LocationListener;
    import com.google.android.gms.location.LocationRequest;



    public class MainActivity extends Activity implements LocationListener {



        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            LocationManager locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
            LocationListener locationListener = new GetCurrentLocation();
            long t = 5000;
            float d = 10;
            locationManager.requestLocationUpdates(
                    LocationManager.GPS_PROVIDER, t, d, locationListener);
    }
}

这是我的GetCurrentLocation.java

import android.app.Activity;
import android.content.Context;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationManager;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Toast;

import com.google.android.gms.location.LocationListener;

import java.io.IOException;
import java.util.List;
import java.util.Locale;

public class GetCurrentLocation extends Activity implements LocationListener {
    String longitude;
    String latitude;
    String cityName;


    @Override
    public void onLocationChanged(Location loc) {
        //editLocation.setText("");
        //pb.setVisibility(View.INVISIBLE);
        longitude = "Longitude: " + loc.getLongitude();
        //Log.v(TAG, longitude);
        latitude = "Latitude: " + loc.getLatitude();
        //Log.v(TAG, latitude);

        /*------- To get city name from coordinates -------- */
        //String cityName = null;
        Geocoder gcd = new Geocoder(getBaseContext(), Locale.getDefault());
        List<Address> addresses;
        try {
            addresses = gcd.getFromLocation(loc.getLatitude(),
                    loc.getLongitude(), 1);
            if (addresses.size() > 0)
                System.out.println(addresses.get(0).getLocality());
            cityName = addresses.get(0).getLocality();
        }
        catch (IOException e) {
            e.printStackTrace();
        }

        //editLocation.setText(s);
    }

    //@Override
    public void onProviderDisabled(String provider) {}

    //@Override
    public void onProviderEnabled(String provider) {}

    //@Override
    public void onStatusChanged(String provider, int status, Bundle extras) {}


}

这些是错误。

Error: MainActivity is not abstract and does not override abstract method onLocationChanged(Location) in LocationListener
Error:(36, 24) error: no suitable method found for requestLocationUpdates(String,long,float,com.google.android.gms.location.LocationListener)
method LocationManager.requestLocationUpdates(long,float,Criteria,PendingIntent) is not applicable
(actual argument String cannot be converted to long by method invocation conversion)
method LocationManager.requestLocationUpdates(String,long,float,PendingIntent) is not applicable
(actual argument com.google.android.gms.location.LocationListener cannot be converted to PendingIntent by method invocation conversion)
method LocationManager.requestLocationUpdates(long,float,Criteria,android.location.LocationListener,Looper) is not applicable
(actual and formal argument lists differ in length)
method LocationManager.requestLocationUpdates(String,long,float,android.location.LocationListener,Looper) is not applicable
(actual and formal argument lists differ in length)
method LocationManager.requestLocationUpdates(String,long,float,android.location.LocationListener) is not applicable
(actual argument com.google.android.gms.location.LocationListener cannot be converted to android.location.LocationListener by method invocation conversion)

基本上两个主要错误是MainActivity不是抽象的，也是请求位置更新。请帮忙。我想要的只是获取当前位置的用户的纬度和经度。