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- android - 无法解析导入android.support.v7.app
- UNIX 域套接字与共享内存(映射文件)
我希望谷歌地图显示用户的位置。我试过这段代码,但它在 Android 6 上不起作用。
private GoogleMap map;
LocationManager lm;
LocationListener ll;
Location l;
LatLng pos;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.start_layout);
lm = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
ll = new LocationListener() {
@Override
public void onLocationChanged(Location location) {
l = (Location) location;
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {}
@Override
public void onProviderEnabled(String provider) {}
@Override
public void onProviderDisabled(String provider) {}
};
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.nMap);
mapFragment.getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap googleMap) {
map = googleMap;
if(ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
lm.requestLocationUpdates(lm.NETWORK_PROVIDER, 0, 0, ll);
}
pos = new LatLng(l.getLatitude(), l.getLongitude());
// Add a marker in Sydney and move the camera
map.setMyLocationEnabled(true);
map.addMarker(new MarkerOptions().position(pos).title("Marker in Sydney"));
map.moveCamera(CameraUpdateFactory.newLatLng(pos));
}
这是我设置的权限:
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
最佳答案
将 FusedLocationProviderClient 与 Google Play Services 11 及更高版本一起使用:
请看这里: How to get current Location in GoogleMap using FusedLocationProviderClient
用于使用(现已弃用)FusedLocationProviderApi:
如果您的项目使用 Google Play Services 10 或更低版本,则使用 FusedLocationProviderApi 是最佳选择。
FusedLocationProviderApi提供比旧的开源 LocationManager API 更少的电池消耗。此外,如果您已经在使用 Google Play Services for Google Maps,那么没有理由不使用它。
这是一个完整的 Activity 类,它在当前位置放置一个 Marker,并将相机移动到当前位置。
它还会在运行时检查 Android 6 及更高版本(Marshmallow、Nougat、Oreo)的位置权限。为了正确处理 Android M/Android 6 及更高版本所需的位置权限运行时检查,您需要确保用户在调用 mGoogleMap.setMyLocationEnabled(true)
之前已授予您的应用程序位置权限> 以及在请求位置更新之前。
public class MapLocationActivity extends AppCompatActivity
implements OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
GoogleMap mGoogleMap;
SupportMapFragment mapFrag;
LocationRequest mLocationRequest;
GoogleApiClient mGoogleApiClient;
Location mLastLocation;
Marker mCurrLocationMarker;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getSupportActionBar().setTitle("Map Location Activity");
mapFrag = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
mapFrag.getMapAsync(this);
}
@Override
public void onPause() {
super.onPause();
//stop location updates when Activity is no longer active
if (mGoogleApiClient != null) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
}
@Override
public void onMapReady(GoogleMap googleMap)
{
mGoogleMap=googleMap;
mGoogleMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
//Initialize Google Play Services
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
//Location Permission already granted
buildGoogleApiClient();
mGoogleMap.setMyLocationEnabled(true);
} else {
//Request Location Permission
checkLocationPermission();
}
}
else {
buildGoogleApiClient();
mGoogleMap.setMyLocationEnabled(true);
}
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
@Override
public void onConnected(Bundle bundle) {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(1000);
mLocationRequest.setFastestInterval(1000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
}
@Override
public void onConnectionSuspended(int i) {}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {}
@Override
public void onLocationChanged(Location location)
{
mLastLocation = location;
if (mCurrLocationMarker != null) {
mCurrLocationMarker.remove();
}
//Place current location marker
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position");
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
mCurrLocationMarker = mGoogleMap.addMarker(markerOptions);
//move map camera
mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng,11));
}
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
private void checkLocationPermission() {
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.ACCESS_FINE_LOCATION)) {
// Show an explanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
new AlertDialog.Builder(this)
.setTitle("Location Permission Needed")
.setMessage("This app needs the Location permission, please accept to use location functionality")
.setPositiveButton("OK", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
//Prompt the user once explanation has been shown
ActivityCompat.requestPermissions(MapLocationActivity.this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION );
}
})
.create()
.show();
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION );
}
}
}
@Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted, yay! Do the
// location-related task you need to do.
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
if (mGoogleApiClient == null) {
buildGoogleApiClient();
}
mGoogleMap.setMyLocationEnabled(true);
}
} else {
// permission denied, boo! Disable the
// functionality that depends on this permission.
Toast.makeText(this, "permission denied", Toast.LENGTH_LONG).show();
}
return;
}
// other 'case' lines to check for other
// permissions this app might request
}
}
}
activity_main.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">
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:map="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/map"
tools:context=".MapLocationActivity"
android:name="com.google.android.gms.maps.SupportMapFragment"/>
</LinearLayout>
结果:
如果需要,使用 AlertDialog 显示权限说明(如果用户拒绝权限请求,或授予权限,然后在设置中撤销它,则会发生这种情况):
通过调用ActivityCompat.requestPermissions()
提示用户位置权限:
在授予位置权限后将相机移动到当前位置并放置标记:
关于android - 如何在 Android Marshmallow 上的 Google map 上显示当前位置?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/34582370/
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