java - Android Fragment中的位置权限

Question

我希望这将是一个简单的修复，并且有人可以帮助我。

我有一个应用程序需要用户位置，以便使用纬度和经度来获取他们所在位置的天气。在选择允许权限后，我能够获取用户位置，保留 fragment ，然后再次返回。问题在于当我在弹出窗口中选择允许时。我需要立即获取位置。希望我的代码是不言自明的。

我冒昧地删除了与我的问题无关的所有代码。此外，我尝试调用 onStart() 但没有成功。

public class FragmentLocalWeather extends Fragment implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener {

private static final int PERMISSION_ACCESS_COARSE_LOCATION = 0;
private GoogleApiClient googleApiClient;

public FragmentLocalWeather() {
    // Required empty public constructor
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.local_weather_fragment, container, false);

    googleApiClient = new GoogleApiClient.Builder(this.getActivity(), this, this).addApi(LocationServices.API).build();

    if (ContextCompat.checkSelfPermission(this.getActivity(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
        ActivityCompat.requestPermissions(this.getActivity(), new String[]{Manifest.permission.ACCESS_COARSE_LOCATION},
                PERMISSION_ACCESS_COARSE_LOCATION);
    }

    setHasOptionsMenu(true);

    return view;
}

@Override
public void onStart() {
    super.onStart();
    if (googleApiClient != null) {
        googleApiClient.connect();
    }
}

@Override
public void onStop() {
    googleApiClient.disconnect();
    super.onStop();

}

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    switch (requestCode) {
        case PERMISSION_ACCESS_COARSE_LOCATION:
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                // ********** problem Area **********
                // Need to user location here.
            } else {
                Toast.makeText(this.getActivity(), "Need your location!", Toast.LENGTH_SHORT).show();
            }
            break;
    }
}

@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
    inflater.inflate(R.menu.menu_local_weather, menu);
    super.onCreateOptionsMenu(menu, inflater);
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();

    switch (id) {
        case R.id.action_settings: {

        }
        case R.id.action_refresh: {
            onStart();
        }
    }

    return true;
}

@Override
public void onConnected(@Nullable Bundle bundle) {
    if (ContextCompat.checkSelfPermission(this.getActivity(), Manifest.permission.ACCESS_COARSE_LOCATION)
            == PackageManager.PERMISSION_GRANTED) {
        Location lastLocation = LocationServices.FusedLocationApi.getLastLocation(googleApiClient);

        double lat = lastLocation.getLatitude(), lon = lastLocation.getLongitude();
        Log.d("dozer74", "===========================>>>>>>>>>>>>> " + lat + " : " + lon);
    }
}

@Override
public void onConnectionSuspended(int i) {

}

@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

}

Answer 1

除了 Marcin 的建议(在问题区域中调用 googleApiClient.connect())之外，我认为您需要在 fragment 中使用 requestPermissions 方法而不是 ActivityCompat.requestPermissions。

fragment 中的 requestPermissions 方法将调用您在 fragment 中定义的 onRequestPermissionsResult，而您当前使用的方法将调用 Activity 内部的 onRequestPermissionsResult() (我猜您尚未重写)。

因此你的 onCreate 看起来更像是:

   if (ContextCompat.checkSelfPermission(this.getActivity(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
    requestPermissions(new String[]{Manifest.permission.ACCESS_COARSE_LOCATION},
            PERMISSION_ACCESS_COARSE_LOCATION);
}