我应该在我的应用程序中打开谷歌地图时直接关注当前用户的位置。 通过大量的研究，我找到了正确的方法（避免所有已弃用的功能），但我仍然找不到正确的方法来检查我的权限。这是我的代码：
LocationProvider.class
public class LocationProvider implements
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
public abstract interface LocationCallback {
public void handleNewLocation(Location location);
}
public static final String TAG = LocationProvider.class.getSimpleName();
/*
* Define a request code to send to Google Play services
* This code is returned in Activity.onActivityResult
*/
private final static int CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000;
private LocationCallback mLocationCallback;
private Context mContext;
private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
int
public LocationProvider(Context context, LocationCallback callback) {
mGoogleApiClient = new GoogleApiClient.Builder(context)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mLocationCallback = callback;
// Create the LocationRequest object
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(10 * 1000) // 10 seconds, in milliseconds
.setFastestInterval(1 * 1000); // 1 second, in milliseconds
mContext = context;
}
public void connect() {
mGoogleApiClient.connect();
}
public void disconnect() {
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
mGoogleApiClient.disconnect();
}
}
@Override
public void onConnected(Bundle bundle) {
Log.i(TAG, "Location services connected.");
if(ContextCompat.checkSelfPermission(,Manifest.permission.ACCESS_COARSE_LOCATION)) {
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if (location == null) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
} else {
mLocationCallback.handleNewLocation(location);
}
}
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
/*
* Google Play services can resolve some errors it detects.
* If the error has a resolution, try sending an Intent to
* start a Google Play services activity that can resolve
* error.
*/
if (connectionResult.hasResolution() && mContext instanceof Activity) {
try {
Activity activity = (Activity)mContext;
// Start an Activity that tries to resolve the error
connectionResult.startResolutionForResult(activity, CONNECTION_FAILURE_RESOLUTION_REQUEST);
/*
* Thrown if Google Play services canceled the original
* PendingIntent
*/
} catch (IntentSender.SendIntentException e) {
// Log the error
e.printStackTrace();
}
} else {
/*
* If no resolution is available, display a dialog to the
* user with the error.
*/
Log.i(TAG, "Location services connection failed with code " + connectionResult.getErrorCode());
}
}
@Override
public void onLocationChanged(Location location) {
mLocationCallback.handleNewLocation(location);
}
}
MapsActivity.class
public class MapsActivity extends FragmentActivity implements LocationProvider.LocationCallback {
public static final String TAG = MapsActivity.class.getSimpleName();
private GoogleMap mMap; // Might be null if Google Play services APK is not available.
private LocationProvider mLocationProvider;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
setUpMapIfNeeded();
mLocationProvider = new LocationProvider(this, this);
}
@Override
protected void onResume() {
super.onResume();
setUpMapIfNeeded();
mLocationProvider.connect();
}
@Override
protected void onPause() {
super.onPause();
mLocationProvider.disconnect();
}
/**
* 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();
}
}
}
/**
* 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"));
}
public void handleNewLocation(Location location) {
Log.d(TAG, location.toString());
double currentLatitude = location.getLatitude();
double currentLongitude = location.getLongitude();
LatLng latLng = new LatLng(currentLatitude, currentLongitude);
//mMap.addMarker(new MarkerOptions().position(new LatLng(currentLatitude, currentLongitude)).title("Current Location"));
MarkerOptions options = new MarkerOptions()
.position(latLng)
.title("I am here!");
mMap.addMarker(options);
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
}
}
我尝试检查此处的权限，但我的活动无法识别：
if(ContextCompat.checkSelfPermission(MapsActivity,Manifest.permission.ACCESS_COARSE_LOCATION)) {
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if (location == null) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
} else {
mLocationCallback.handleNewLocation(location);
}
}
目标很简单，只需打开谷歌地图，我当前的GPS位置在中心。但是所有资源和论坛都已过时。
非常感谢你的帮助!!