为什么onLocationChanged函数对我不起作用?

时间:2015-05-02 08:07:01

标签: android gps

我一直在使用gps传感器编写应用程序以获取您的位置并将地图置于您周围,我一直在使用该功能:

final LocationListener locationListenerFunc = new LocationListener()

但它不能为我工作,我已经去了几个小时,但我仍然没有看到文字的变化(当你进入onLocationChanged方法时我会改变它, 我通过这个例子来做所有事情。

这是我的代码> 问题是什么?

package greenroadproject.greenroadproject2;

import android.content.Context;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.text.format.Time;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.CameraPosition;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;

public class MapsActivity extends FragmentActivity {

    private GoogleMap mMap; // Might be null if Google Play services APK is not available.
    private Button startTrackingButton;
    private Button stopTrackingButton;
    private TextView mainText;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.map_fragment_layout);

        //GPS LOCATION MANAGER
        final LocationManager manager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
        final LocationListener locationListenerFunc = new LocationListener() {

            @Override
            public void onLocationChanged(Location location) {
                /// HERE IS MY PROBLEM HE DOESN'T GO IN HERE
                /// HERE IS MY PROBLEM HE DOESN'T GO IN HERE
                mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(
                        new LatLng(location.getLatitude(), location.getLongitude()), 13));

                CameraPosition cameraPosition = new CameraPosition.Builder()
                        .target(new LatLng(location.getLatitude(), location.getLongitude()))      // Sets the center of the map to location user
                        .zoom(17)                   // Sets the zoom
                        .bearing(90)                // Sets the orientation of the camera to east
                        .tilt(30)                   // Sets the tilt of the camera to 30 degrees
                        .build();                   // Creates a CameraPosition from the builder
                mMap.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));



                Time today = new Time(Time.getCurrentTimezone());
                today.setToNow();

                mainText.setText("gotNew Location at: "+today.format("%k:%M:%S"));
                ///
            }

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

            }

            @Override
            public void onProviderEnabled(String provider) {

            }

            @Override
            public void onProviderDisabled(String provider) {

            }
        };


        //casting to button
        startTrackingButton = (Button) findViewById(R.id.BTStartTracking);
        stopTrackingButton = (Button) findViewById(R.id.BTStopTracking);
        mainText = (TextView) findViewById(R.id.TVMainTextView);

        //setting up map
        setUpMapIfNeeded();

        //start tracking button touch listener
        stopTrackingButton.setOnClickListener(new Button.OnClickListener() {
            public void onClick(View v) {
                //Do stuff here
                centerMapOnMyLocation(); //centers the map on user location
                mainText.setText("user location enabled");

            }
        });

        //stop tracking button touch listener
        startTrackingButton.setOnClickListener(new Button.OnClickListener() {
            public void onClick(View v) {
                //Do stuff here
                Time today = new Time(Time.getCurrentTimezone());
                today.setToNow();

                mainText.setText("first time is:  "+today.format("%k:%M:%S"));

                manager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
                        3000, 0, locationListenerFunc);


            }
        });




    }

    @Override
    protected void onResume() {
        super.onResume();
        setUpMapIfNeeded();
    }

    /**
     * Sets up the map if it is possible to do so (i.e., the Google Play services APK is correctly
     * installed) and the map has not already been instantiated.. This will ensure that we only ever
     * call {@link #setUpMap()} once when {@link #mMap} is not null.
     * <p/>
     * If it isn't installed {@link SupportMapFragment} (and
     * {@link com.google.android.gms.maps.MapView MapView}) will show a prompt for the user to
     * install/update the Google Play services APK on their device.
     * <p/>
     * A user can return to this FragmentActivity after following the prompt and correctly
     * installing/updating/enabling the Google Play services. Since the FragmentActivity may not
     * have been completely destroyed during this process (it is likely that it would only be
     * stopped or paused), {@link #onCreate(Bundle)} may not be called again so we should call this
     * method in {@link #onResume()} to guarantee that it will be called.
     */
    private void setUpMapIfNeeded() {
        // Do a null check to confirm that we have not already instantiated the map.
        if (mMap == null) {
            // Try to obtain the map from the SupportMapFragment.
            mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
                    .getMap();
            // Check if we were successful in obtaining the map.
            if (mMap != null) {
                //setUpMap();
                centerMapOnMyLocation(); //centers the map on user location
            }
        }
    }

    /**
     * This is where we can add markers or lines, add listeners or move the camera. In this case, we
     * just add a marker near Africa.
     * <p/>
     * This should only be called once and when we are sure that {@link #mMap} is not null.
     */
    private void setUpMap() {
        mMap.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker"));
    }



    private void centerMapOnMyLocation() {

        LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        Criteria criteria = new Criteria();

        Location location = locationManager.getLastKnownLocation(locationManager.getBestProvider(criteria, false));

        //sets text >
        double Lad = location.getLatitude();
        double Long = location.getLongitude();
        mainText.setText("lat: "+ String.valueOf(Lad)+", "+ "long: " +String.valueOf(Long));

        if (location != null)
        {
            mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(
                    new LatLng(location.getLatitude(), location.getLongitude()), 13));

            CameraPosition cameraPosition = new CameraPosition.Builder()
                    .target(new LatLng(location.getLatitude(), location.getLongitude()))      // Sets the center of the map to location user
                    .zoom(17)                   // Sets the zoom
                    .bearing(90)                // Sets the orientation of the camera to east
                    .tilt(30)                   // Sets the tilt of the camera to 30 degrees
                    .build();                   // Creates a CameraPosition from the builder
            mMap.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));

        }

    }


}

1 个答案:

答案 0 :(得分:1)

LocationManager.GPS_PROVIDER更改为LocationManager.NETWORK_PROVIDER