GpsStatus.Listener仅在GPS打开时有效

Question

在我的应用程序中,我有一个GpsStatus.Listener,用于在用户启用或禁用GPS时接收事件.如果在启动应用程序之前启用GPS,一切正常.在这种情况下,每次打开或关闭GPS时,我都会收到GPS_EVENT_STARTED或GPS_EVENT_STOPPED.

问题是如果应用程序启动时GPS已关闭.在这种情况下,如果我打开或关闭GPS,我不会收到任何事件.

有人可以向我解释一下吗？

这是我的代码:

public class GPSTracker implements android.location.GpsStatus.Listener {

    private final Context context;
    private final LocationListener locListener;
    private LocationManager locationManager;
    private boolean isGPSEnabled = false;

    public GPSTracker(Context context, LocationListener locListener) {
            this.context = context;
            this.locListener = locListener; 
            setupGPS();
    }

    private void setupGPS() {
            locationManager = (LocationManager) getContext().getSystemService(Context.LOCATION_SERVICE);                
            locationManager.addGpsStatusListener(this);
            isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
            if(!isGPSEnabled) {
                    Toast.makeText(getContext(), "GPS disabled", Toast.LENGTH_SHORT).show();
            } else {        
                    locationManager.removeUpdates(locListener);
                    locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME, MIN_DISTANCE, locListener);
            }
    }

    @Override
    public void onGpsStatusChanged(int event) {
            Log.e("onGpsStatusChanged", event+""); 
            switch(event) {
            case GpsStatus.GPS_EVENT_STARTED:
                    Log.e("onGpsStatusChanged", "GPS_EVENT_STARTED");
                    break;
            case GpsStatus.GPS_EVENT_STOPPED:
                    Log.e("onGpsStatusChanged", "GPS_EVENT_STOPPED");
                    break;
            }
    }

所以,我的logcat输出是(如果GPS在启动时打开):

• GpsStatusChanged(24638):1 //应用程序启动
• GpsStatusChanged(24638):GPS_EVENT_STARTED
• GpsStatusChanged(24638):4 //搜索修复
• GpsStatusChanged(24638):4
• GpsStatusChanged(24638):2 //关闭GPS
• GpsStatusChanged(24638):GPS_EVENT_STOPED

GPS关机输出:没有.

Answer 1

好吧,LocationListener已经提供:

onProviderDisabled(),onProviderEnabled()并onStatusChanged()出于这样的目的.

GpsStatus.Listener提供有关GPS服务内部运作的信息.它不能用于告知GPS提供商的状态.

LocationListener提供有关提供商的信息 当您LocationListener向位置提供商注册时,会相应地调用onProviderEnabled()/ onProviderDisabled(),并且您的应用程序始终可以告知GPS何时打开或关闭.

试试这个:

public class test extends Activity implements LocationListener{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        lm.requestLocationUpdates(LocationManager.GPS_PROVIDER,1000,10,this);
    }


    @Override
    public void onLocationChanged(Location location) {
    }

    @Override
    public void onStatusChanged(String s, int i, Bundle bundle) {
    }

    @Override
    public void onProviderEnabled(String s) {
        if(LocationManager.GPS_PROVIDER.equals(s)){
            Toast.makeText(this,"GPS on",Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    public void onProviderDisabled(String s) {
        if(LocationManager.GPS_PROVIDER.equals(s)){
            Toast.makeText(this,"GPS off",Toast.LENGTH_SHORT).show();
        }
    }
}