从页面导航到另一个页面容器google_maps将导致黑屏

Question

我想从我的应用导航至google_maps。但是，当我单击映射到googe_map页面的Iconbutton时，会出现黑屏。

这是Iconbutton的代码段。

                    leading: new IconButton(
                      tooltip: 'Previous choice',
                      icon: const Icon(
                        Icons.location_on,
                        size: 45,
                      ),
                      onPressed: () {
                        print('button clicked');
                        Navigator.pushReplacement(
                            context,
                            MaterialPageRoute(
                              builder: (context) => MapAdd(),
                            ));
                      },
                    ),

编辑：MapAdd（）的代码。当我将此代码作为独立实体运行时，它会运行并显示地图，但是当我将其与其他页面结合使用时，当我通过IconButton导航到该页面时，就会出现空白屏幕。

class MapAdd extends StatefulWidget {
  @override
  _MapAddState createState() => _MapAddState();
}

class _MapAddState extends State<MapAdd> {
  Completer<GoogleMapController> _controller = Completer();

  GoogleMapController mapController;

  static const LatLng _center = const LatLng(27.7172, 85.3240);

  final Set<Marker> _markers = {};

  LatLng _lastMapPosition = _center;

  MapType _currentMapType = MapType.normal;

  @override
  void initState() {
    super.initState();
    PermissionHandler()
        .checkPermissionStatus(PermissionGroup.locationWhenInUse)
        .then(_updateStatus);
  }

  void _onMapTypeButtonPressed() {
    setState(() {
      _currentMapType = _currentMapType == MapType.normal
          ? MapType.satellite
          : MapType.normal;
    });
  }

  void _onAddMarkerButtonPressed() {
    setState(() {
      _markers.add(Marker(
        // This marker id can be anything that uniquely identifies each marker.
        markerId: MarkerId(_lastMapPosition.toString()),
        draggable: true,
        position: _lastMapPosition,

        infoWindow: InfoWindow(
          title: 'Really cool place',
          snippet: '5 Star Rating',
        ),
        icon: BitmapDescriptor.defaultMarker,
      ));
    });
  }

  void _onCameraMove(CameraPosition position) {
    _lastMapPosition = position.target;
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          ),
        ),
        body: Stack(
          children: <Widget>[
            Container(
              child: GoogleMap(
                onMapCreated: (GoogleMapController controller) {
                  mapController = controller;
                },
                initialCameraPosition: CameraPosition(
                  target: _center,
                  zoom: 11.0,
                ),
                mapType: _currentMapType,
                markers: _markers,
                rotateGesturesEnabled: true,
                scrollGesturesEnabled: true,
                tiltGesturesEnabled: true,
                onCameraMove: _onCameraMove,
              ),
            ),
          ],
        ),
      ),
    );
  }
}

编辑：当我删除按钮和文本字段时，导航有效。但是，当我在“ body：Stack”中添加以下部分时，它不起作用：

 Padding(
              padding: const EdgeInsets.all(18.0),
              child: Column(
                children: <Widget>[
                  TextField(
                    textInputAction: TextInputAction.search,
                    decoration: InputDecoration(
                        filled: true,
                        fillColor: Colors.white,
                        hintText: "Select Delivery Address",
                        border: OutlineInputBorder(
                            borderRadius: BorderRadius.circular(25.0)),
                        contentPadding: EdgeInsets.only(left: 15.0, top: 15.0),
                        suffixIcon: IconButton(
                          icon: Icon(Icons.search),
                          onPressed: () {
                            print("Map button clicked");
                          },
                          iconSize: 30.0,
                        )),
                  ),
                  SizedBox(height: 16.0),
                  Row(
                    mainAxisAlignment: MainAxisAlignment.end,
                    children: <Widget>[
                      FloatingActionButton(
                        onPressed: _onMapTypeButtonPressed,
                        materialTapTargetSize: MaterialTapTargetSize.padded,
                        backgroundColor: Colors.green,
                        child: const Icon(Icons.map, size: 36.0),
                      ),
                    ],
                  ),
                  SizedBox(height: 16.0),
                  Row(
                    mainAxisAlignment: MainAxisAlignment.end,
                    children: <Widget>[
                      FloatingActionButton(
                        onPressed: _onAddMarkerButtonPressed,
                        materialTapTargetSize: MaterialTapTargetSize.padded,
                        backgroundColor: Colors.green,
                        child: const Icon(Icons.add_location, size: 36.0),
                      ),
                    ],
                  ),
                ],
              ),
            ),