我正在制作一个应用程序，并且正在使用Googlemaps。 下面是我的代码 我尝试了很多不同的代码，但是没有用
我的应用无法正常工作，并不断出现此错误
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.maps.SupportMapFragment.getMapAsync(com.google.android.gms.maps.OnMapReadyCallback)' on a null object reference
at com.example.yoons.honey.Map.onCreate(Map.java:59)
xml代码：
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".Map"
tools:layout_editor_absoluteY="81dp">
<Button android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:id="@+id/button"
android:text="my location"/>
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:map="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/map"
android:name="com.google.android.gms.maps.SupportMapFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.imaadv.leaynik.ClinicFragment"
android:layout_below="@+id/button"/>
/>
活动代码：
public class Map extends AppCompatActivity {
private static final String TAG = "MainActivity";
SupportMapFragment mapFragment;
GoogleMap map;
MarkerOptions myLocationMarker;
private CompassView mCompassView;
private SensorManager mSensorManager;
private boolean mCompassEnabled;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
mapFragment.getMapAsync(new OnMapReadyCallback() { //This is the error I think
@Override
public void onMapReady(GoogleMap googleMap) {
Log.d(TAG, "GoogleMap is ready.");
map = googleMap;
onResume();
map.setMyLocationEnabled(true);
}
});
try {
MapsInitializer.initialize(this);
} catch (Exception e) {
e.printStackTrace();
}
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
requestMyLocation();
}
});
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
boolean sideBottom = true;
mCompassView = new CompassView(this);
mCompassView.setVisibility(View.VISIBLE);
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(
RelativeLayout.LayoutParams.WRAP_CONTENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.ALIGN_PARENT_LEFT);
params.addRule(sideBottom ? RelativeLayout.ALIGN_PARENT_BOTTOM : RelativeLayout.ALIGN_PARENT_TOP);
((ViewGroup) mapFragment.getView()).addView(mCompassView, params);
mCompassEnabled = true;
}
private void requestMyLocation() {
LocationManager manager =
(LocationManager) getSystemService(Context.LOCATION_SERVICE);
try {
long minTime = 10000;
float minDistance = 0;
manager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
minTime,
minDistance,
new LocationListener() {
@Override
public void onLocationChanged(Location location) {
showCurrentLocation(location);
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
}
);
Location lastLocation = manager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (lastLocation != null) {
showCurrentLocation(lastLocation);
}
manager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
minTime,
minDistance,
new LocationListener() {
@Override
public void onLocationChanged(Location location) {
showCurrentLocation(location);
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
}
);
} catch (SecurityException e) {
e.printStackTrace();
}
}
private void showCurrentLocation(Location location) {
LatLng curPoint = new LatLng(location.getLatitude(), location.getLongitude());
map.animateCamera(CameraUpdateFactory.newLatLngZoom(curPoint, 15));
showMyLocationMarker(location);
}
private void showMyLocationMarker(Location location) {
if (myLocationMarker == null) {
myLocationMarker = new MarkerOptions();
myLocationMarker.position(new LatLng(location.getLatitude(), location.getLongitude()));
myLocationMarker.title("�뿈 �궡 �쐞移?n");
myLocationMarker.snippet("�뿈 GPS濡� �솗�씤�븳 �쐞移�");
myLocationMarker.icon(BitmapDescriptorFactory.fromResource(R.mipmap.mylocation));
map.addMarker(myLocationMarker);
} else {
myLocationMarker.position(new LatLng(location.getLatitude(), location.getLongitude()));
}
}
@Override
protected void onPause() {
super.onPause();
if (map != null) {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
map.setMyLocationEnabled(false);
}
if (mCompassEnabled) {
mSensorManager.unregisterListener(mListener);
}
}
@Override
protected void onResume() {
super.onResume();
if (map != null) {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
map.setMyLocationEnabled(true);
}
if(mCompassEnabled) {
mSensorManager.registerListener(mListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ORIENTATION), SensorManager.SENSOR_DELAY_UI);
}
}
private final SensorEventListener mListener = new SensorEventListener() {
private int iOrientation = Surface.ROTATION_0;
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
public void onSensorChanged(SensorEvent event) {
if (iOrientation < 0) {
iOrientation = ((WindowManager) getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay().getRotation();
}
mCompassView.setAzimuth(event.values[0] + 90 * iOrientation);
mCompassView.invalidate();
}
};
}
我浏览了很多这样的问题。 我试图夸大我的观点，但是当我尝试
View view = inflater.inflate(R.layout.map, null, false);
充气机上有一条红线。它说它无法解析符号“充气机”
当我尝试使用getChildFragmentManager而不是getSupportFragmentManager时，我也有一条红线
我想我已经获得了所有用户的许可