Android 向动态谷歌地图添加标记
我正在开发一个应用程序,显示具有指定LatLng值的地图。 映射片段是动态的(不是R.id.map) 当我试图将一个标记添加到指定的位置(从GooglePlacesAPI JSON请求中获取)时,我得到的是一个空指针 代码如下:Android 向动态谷歌地图添加标记,android,google-maps,google-play-services,marker,supportmapfragment,Android,Google Maps,Google Play Services,Marker,Supportmapfragment,我正在开发一个应用程序,显示具有指定LatLng值的地图。 映射片段是动态的(不是R.id.map) 当我试图将一个标记添加到指定的位置(从GooglePlacesAPI JSON请求中获取)时,我得到的是一个空指针 代码如下: @Override public void initMap(int position, long id, ListView listView) { Cursor cursor = (Cursor) listView.getItemAtPositi
@Override
public void initMap(int position, long id, ListView listView) {
Cursor cursor = (Cursor) listView.getItemAtPosition(position);
String lat = cursor.getString(cursor.getColumnIndexOrThrow(PlacesContract.Places.LAT));
String lng = cursor.getString(cursor.getColumnIndexOrThrow(PlacesContract.Places.LNG));
String name = cursor.getString(cursor.getColumnIndexOrThrow(PlacesContract.Places.NAME));
LatLng latLng = new LatLng(Double.parseDouble(lat), Double.parseDouble(lng));
GoogleMapOptions options = new GoogleMapOptions();
options.mapType(GoogleMap.MAP_TYPE_HYBRID);
options.camera(CameraPosition.fromLatLngZoom(latLng, 15));
mapFragment = GoogleMapFragment.newInstance(options);
mUIGoogleMap.addMarker(new MarkerOptions().position(latLng).title(name));
if (findViewById(R.id.map_container) != null) {
getSupportFragmentManager().beginTransaction().replace(R.id.map_container, mapFragment).addToBackStack(null).commit();
} else {
getSupportFragmentManager().beginTransaction().replace(R.id.listview_container, mapFragment).addToBackStack(null).commit();
}
}
GoogleMapFragment类=
public class GoogleMapFragment extends SupportMapFragment {
private static final String SUPPORT_MAP_BUNDLE_KEY = "MapOptions";
public static interface OnGoogleMapFragmentListener {
void onMapReady(GoogleMap map);
}
public static GoogleMapFragment newInstance() {
GoogleMapFragment fragment = new GoogleMapFragment();
return fragment;
}
public static GoogleMapFragment newInstance(GoogleMapOptions options) {
Bundle arguments = new Bundle();
arguments.putParcelable(SUPPORT_MAP_BUNDLE_KEY, options);
GoogleMapFragment fragment = new GoogleMapFragment();
fragment.setArguments(arguments);
return fragment;
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
try {
mCallback = (OnGoogleMapFragmentListener) getActivity();
} catch (ClassCastException e) {
throw new ClassCastException(getActivity().getClass().getName() + " must implement OnGoogleMapFragmentListener");
}
}
@Override
public View onCreateView(LayoutInflater arg0, ViewGroup arg1, Bundle arg2) {
View v = super.onCreateView(arg0, arg1, arg2);
Fragment fragment = getParentFragment();
return v;
}
private OnGoogleMapFragmentListener mCallback;
}
错误日志:
03-01 13:40:36.069 17720-17720/com.fragments.ofir.nearby E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.fragments.ofir.nearby, PID: 17720
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.fragments.ofir.nearby.MainActivity.initMap(MainActivity.java:184)
at com.fragments.ofir.nearby.fragments.ResultsFragment.onItemClick(ResultsFragment.java:113)
at android.widget.AdapterView.performItemClick(AdapterView.java:300)
at android.widget.AbsListView.performItemClick(AbsListView.java:1186)
at android.widget.AbsListView$PerformClick.run(AbsListView.java:3095)
at android.widget.AbsListView$3.run(AbsListView.java:4038)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5274)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
您应该尝试扩展SupportMapFragment类,而不是创建SupportMapFragment的新实例。检查。您是否正确地获得了latLng(非空)?你能发布你的错误日志吗?@Sadiq我已经将错误日志添加到了问题中,是的,我得到了正确的LatLng,没有addmarker()方法,地图工作得很好。@如果这样,你能告诉我哪一行是184吗?mapFragment.getMap().addmarker(新的MarkerOptions().position(LatLng))@Arshdeep\u somalStill获取空指针。。所有的工作都完成了。我在原始问题中添加了GoogleMapFragment自定义类,通过使用全局变量,并在OnMapReady回调中添加标记,我成功地做到了这一点。没有更好的办法了吗?