位置按钮不起作用GoogleMaps v2

Question

    public class MapsActivity extends FragmentActivity implements
        OnMapReadyCallback{
private GoogleMap mMap;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_maps);
    // Obtain the SupportMapFragment and get notified when the map is ready to be used.
    SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
            .findFragmentById(R.id.map);
    mapFragment.getMapAsync(this);
}

@Override
public void onMapReady(GoogleMap map) {
    mMap = map;

    LatLng sydney = new LatLng(-34, 151);
    mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));
    mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));
    if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
            == PackageManager.PERMISSION_GRANTED) {
        mMap.setMyLocationEnabled(true);
    } else {
        // Show rationale and request permission.
    }

}
在清单文件中：
提前感谢…
                

Answer 1

在api级别23中，您需要以编程方式检查权限。您正在检查位置权限，如果已授予，则将位置设置为启用。如果未授予许可，您可以请求许可。

if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
        == PackageManager.PERMISSION_GRANTED) {
    mMap.setMyLocationEnabled(true);
} else {
    ActivityCompat.requestPermissions(MapActivity.this,
                new String[]{Manifest.permission.ACCESS_FINE_LOCATION},REQUEST_CODE);
}

然后可以通过重写此方法来处理结果。

@Override
public void onRequestPermissionsResult(int requestCode,
                                       String permissions[], int[] grantResults) {
    switch (requestCode) {
        case REQUEST_CODE: {
            if (grantResults.length > 0
                    && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                //do something
            } else {
                finish();
            }
            break;
        }
    }
}

此外，您还可以从模拟器的设置中为应用程序授予权限。

final GoogleMap mMap = map; 
map.setOnMyLocationButtonClickListener(new GoogleMap.OnMyLocationButtonClickListener() {
        @Override
        public boolean onMyLocationButtonClick() {
            LatLng loc = new LatLng(mMap.getMyLocation().getLatitude(),mMap.getMyLocation().getLongitude());
            mMap.moveCamera(CameraUpdateFactory.newLatLng(loc));
            return true;
        }
    });