将 SupportMapFragment 添加到 LinearLayout

Question

我需要添加一个使用 AndroidStudio 创建的 SupportMapFragment。使用它的片段活动工作正常。它在悉尼显示带有标记的地图。 但我需要将该地图放在一个 Layout（即 LinearLayout）上以添加按钮并与地图进行交互。

我创建了一个类 MapsActivity.java 及其对应的布局 activity_maps.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Some Text"
        android:id="@+id/textView" />


    <fragment xmlns:map="http://schemas.android.com/apk/res-auto"
        android:id="@+id/map"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:scrollbars="vertical"
        class="com.google.android.gms.maps.SupportMapFragment"/>

</LinearLayout>

既然如此：public class MapsActivity extends AppCompatActivity，在 MainActivity.onCreate() 里面我试过了：

1)

    android.support.v4.app.FragmentManager manager = getSupportFragmentManager();
    SupportMapFragment mapFragment = SupportMapFragment.newInstance();
    manager.beginTransaction().replace(R.id.map, mapFragment).commit();
    setContentView(R.layout.activity_maps);
    GoogleMap mMap = mapFragment.getMap();
    // NOT GOOD: nMap is null.

2)

    FragmentManager manager = getChildFragmentManager();
    [...]
    // NOT GOOD: Cannot resolve method getChildFragmentManager.

3)

    GoogleMap mMap = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();
    // NOT GOOD: nMap is null.

接下来我可以尝试什么？

Answer 1

试试这样。修改第一个

您正在创建新的MapFragment 使用 SupportMapFragment.newInstance(); 而不是从 xml 获取 地图片段

FragmentManager myFragmentManager = getSupportFragmentManager();
    mapFragment = (SupportMapFragment) myFragmentManager
            .findFragmentById(R.id.map);

    map = mapFragment.getMap();

Answer 2

让您的Activity 实现OnMapReadyCallback。例如

public class MapsActivity extends AppCompatActivity implements OnMapReadyCallback {

在onCreate，在setContentView 之后，你做

SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
            .findFragmentById(R.id.map);
mapFragment.getMapAsync(this);

当onMapReady 被调用时，你可以使用googleMap

@Override
public void onMapReady(GoogleMap googleMap) {

GoogleMap 对象准备好供您使用可能需要一段时间，因此 getMapAsync 和 OnMapReadyCallback

Answer 3

我在这里发布了谁会感兴趣的完整答案，我发现它不是那么直观。这使您可以将地图添加到自定义布局中。

public class MapsActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps);

        FragmentManager myFragmentManager = getSupportFragmentManager();
        SupportMapFragment mapFragment = (SupportMapFragment) myFragmentManager.findFragmentById(R.id.map);
        GoogleMap mMap = mapFragment.getMap();

        // Add a marker in Sydney and move the camera
        LatLng sydney = new LatLng(-35, 152);
        mMap.addMarker(new MarkerOptions().position(sydney).title("Marker near Sidney"));
        mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));
    }

}

布局：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Some Text"
        android:id="@+id/textView" />


    <fragment xmlns:map="http://schemas.android.com/apk/res-auto"
        android:id="@+id/map"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:scrollbars="vertical"
        class="com.google.android.gms.maps.SupportMapFragment"/>

</LinearLayout>

Answer 4

这种方式可以在屏幕上显示谷歌地图

<fragment
    android:id="@+id/map"
    class="com.google.android.gms.maps.SupportMapFragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

public class RouteFinderActivity extends AppCompatActivity implements OnMapReadyCallback {

    GoogleMap map;
    Location location;
    Button btn_search_route;
    EditText et_source, et_destination;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_route_finder);
        btn_search_route = findViewById(R.id.btn_search_route);
        et_source = findViewById(R.id.et_source);
        et_destination = findViewById(R.id.et_destination);

        btn_search_route.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String source = et_source.getText().toString();
                String destination = et_destination.getText().toString();

                if (TextUtils.isEmpty(source)) {
                    et_source.setError("Enter Soruce point");
                } else if (TextUtils.isEmpty(destination)) {
                    et_destination.setError("Enter Destination Point");
                } else {
                    String sendstring="http://maps.google.com/maps?saddr=" +
                            source +
                            "&daddr=" +
                            destination;
                    Intent intent = new Intent(android.content.Intent.ACTION_VIEW,
                            Uri.parse(sendstring));
                    startActivity(intent);
                }
            }

        });

        ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)).getMapAsync(this);
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        map = googleMap;
        map.setMapType(1);
        map.setMyLocationEnabled(true);

        LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        Criteria criteria = new Criteria();
        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED
                && ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) == PackageManager.PERMISSION_GRANTED) {

            location = locationManager.getLastKnownLocation(locationManager.getBestProvider(criteria, false));

            if (location != null) {
                //zoom
                CameraPosition cameraPosition = new CameraPosition.Builder()
                        .zoom(17)
                        .target(new LatLng(location.getLatitude(), location.getLongitude()))
                        .bearing(90)
                        .tilt(40)
                        .build();
                map.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
            }
        }
    }
}

清单

<meta-data
    android:name="com.google.android.gms.version"
    android:value="@integer/google_play_services_version" />
<meta-data
    android:name="com.google.android.maps.v2.API_KEY"
    android:value="apikeymap" />