Question

我正在用Google地图制作搜索栏。如果我尝试在某处搜索，该应用将关闭这是我得到的错误

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'com.google.android.gms.maps.model.Marker com.google.android.gms.maps.GoogleMap.addMarker(com.google.android.gms.maps.model.MarkerOptions)' on a null object reference
                  at com.example.yoons.honey.RealMap.onMapSearch(RealMap.java:71)

map.java

public class RealMap extends AppCompatActivity implements OnMapReadyCallback {

private Button searchButton;
GoogleMap mMap;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.real_map);
    SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
    mapFragment.getMapAsync((OnMapReadyCallback) this);

    searchButton = new Button(this);
    searchButton.setOnClickListener(search);
}


@Override
public void onMapReady(GoogleMap googleMap) {
    LatLng sydney = new LatLng(-33.852, 151.211);
    googleMap.addMarker(new MarkerOptions().position(sydney)
            .title("Marker in Sydney"));
    googleMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));
}

private  View.OnClickListener search=new View.OnClickListener(){
    public void onClick(View v){
        onMapSearch(v);
    }
};

public void onMapSearch(View view) {
    EditText locationSearch = (EditText) findViewById(R.id.editText);
    String location = locationSearch.getText().toString();
    List<Address> addressList = null;
    if (location != null || !location.equals("")) {
        Geocoder geocoder = new Geocoder(this);
        try {
            addressList = geocoder.getFromLocationName(location, 1);

        } catch (IOException e) {
            e.printStackTrace();
        }


        if (addressList != null && addressList.size() != 0) {
            Address address = addressList.get(0);
            LatLng latLng = new LatLng(address.getLatitude(), address.getLongitude());
            mMap.addMarker(new MarkerOptions().position(latLng).title("Marker"));
            mMap.animateCamera(CameraUpdateFactory.newLatLng(latLng));
        } else {
            Toast.makeText(getApplicationContext(), "location not found", Toast.LENGTH_SHORT).show();
        }

    }


}

}

我不知道我的代码为什么不起作用我在互联网上复制了大部分代码这是我认为最常见的搜索条形码，但对我不起作用

Answer 1

将googleMap引用传递给您的变量mMap为：-

public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;
    LatLng sydney = new LatLng(-33.852, 151.211);
    googleMap.addMarker(new MarkerOptions().position(sydney)
            .title("Marker in Sydney"));
    googleMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));
}

Android Google Maps Marker空指针错误

1 个答案: