android谷歌地图标记空指针错误

Question

我正在用谷歌地图制作一个搜索栏。 如果我尝试在某个地方搜索应用程序将关闭 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();
        }

    }


}

}

我不知道为什么我的代码不起作用 我复制了互联网上的大部分代码 这是我认为最常见的搜索条形码，但它对我不起作用

Answer 1

将 googleMap 引用传递给您的变量 mMap：-

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));
}