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我想获得定期(比如每 2 分钟)的当前位置更新我正在关注官方文档,我编写了这段代码,但即使在我传递的 LocationRequest 对象中指定,它也没有每两分钟提供一次当前位置更新在 requestLocationUpdates() 中,代码如下:
public class MapsActivity extends FragmentActivity implements OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener{
private FusedLocationProviderClient FusedLocationClient;
private GoogleApiClient mGoogleApiClient;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
if (mGoogleApiClient == null) {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
SupportMapFragment map =
getSupportFragmentManager().findFragmentById(R.id.map));
map.getMapAsync(this);
FusedLocationClient LocationServices.getFusedLocationProviderClient(this);
}
@Override
public void onConnected(Bundle bundle) {
FusedLocationClient.getLastLocation()
.addOnSuccessListener(this, new OnSuccessListener<Location>() {
@Override
public void onSuccess(Location location) {
if (location != null) {
Log.i("MainActivity ", "" + location.getLongitude())
}
}
});
FusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
FusedLocationClient.requestLocationUpdates(requestLocation(),
new LocationCallback(){
@Override
public void onLocationResult(LocationResult locationResult) {
for (Location location : locationResult.getLocations()) {
Log.i("MainActivity ", "" + location.getLongitude());
//not getting current location updates every 2 minutes
}
};
},null);
}
@Override
public void onConnectionSuspended(int i) {}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {}
最佳答案
这类似于我的 other answer here , 更新为使用最近推出的 FusedLocationProviderClient类。
为了将 FusedLocationProviderClient 与 Google map 结合使用:
等待 Google map 准备就绪
如果需要,在运行时请求位置权限
在授予权限后请求位置更新
获取用户位置后更新谷歌地图
首先确保您使用的是至少版本 11 的 Google Play 服务,因为旧版本没有 FusedLocationProviderClient 类(新版本也可以使用):
dependencies {
implementation 'com.google.android.gms:play-services-maps:17.0.0'
implementation 'com.google.android.gms:play-services-location:17.0.0'
//........
}
请注意,FusedLocationProviderClient 存在于版本 11.0.2 中,但由于初始实现中的错误,建议您仅在 11.6.0 及更高版本上使用此类。来自文档:
Note: It's recommended to use Google Play services version 11.6.0 or higher, which includes bug fixes for this class.
在 AndroidManifest.xml 文件中,manifest
标签内和 application
标签外添加位置权限:
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
将 API key 添加到 application
标记内的 AndroidManifest.xml:
<meta-data
android:name="com.google.android.geo.API_KEY"
android:value="AIza___YOUR_KEY_HERE______"/>
Kotlin
这是 Kotlin 中完整的 Activity 类:
class MapsActivity : AppCompatActivity(), OnMapReadyCallback {
lateinit var mGoogleMap: GoogleMap
var mapFrag: SupportMapFragment? = null
lateinit var mLocationRequest: LocationRequest
var mLastLocation: Location? = null
internal var mCurrLocationMarker: Marker? = null
internal var mFusedLocationClient: FusedLocationProviderClient? = null
internal var mLocationCallback: LocationCallback = object : LocationCallback() {
override fun onLocationResult(locationResult: LocationResult) {
val locationList = locationResult.locations
if (locationList.isNotEmpty()) {
//The last location in the list is the newest
val location = locationList.last()
Log.i("MapsActivity", "Location: " + location.getLatitude() + " " + location.getLongitude())
mLastLocation = location
if (mCurrLocationMarker != null) {
mCurrLocationMarker?.remove()
}
//Place current location marker
val latLng = LatLng(location.latitude, location.longitude)
val markerOptions = 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, 11.0F))
}
}
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_maps)
supportActionBar?.title = "Map Location Activity"
mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this)
mapFrag = supportFragmentManager.findFragmentById(R.id.map) as SupportMapFragment?
mapFrag?.getMapAsync(this)
}
public override fun onPause() {
super.onPause()
//stop location updates when Activity is no longer active
mFusedLocationClient?.removeLocationUpdates(mLocationCallback)
}
override fun onMapReady(googleMap: GoogleMap) {
mGoogleMap = googleMap
mGoogleMap.mapType = GoogleMap.MAP_TYPE_HYBRID
mLocationRequest = LocationRequest()
mLocationRequest.interval = 120000 // two minute interval
mLocationRequest.fastestInterval = 120000
mLocationRequest.priority = LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(
this,
Manifest.permission.ACCESS_FINE_LOCATION
) == PackageManager.PERMISSION_GRANTED
) {
//Location Permission already granted
mFusedLocationClient?.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper())
mGoogleMap.isMyLocationEnabled = true
} else {
//Request Location Permission
checkLocationPermission()
}
} else {
mFusedLocationClient?.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper())
mGoogleMap.isMyLocationEnabled = true
}
}
private fun checkLocationPermission() {
if (ActivityCompat.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.
AlertDialog.Builder(this)
.setTitle("Location Permission Needed")
.setMessage("This app needs the Location permission, please accept to use location functionality")
.setPositiveButton(
"OK"
) { _, _ ->
//Prompt the user once explanation has been shown
ActivityCompat.requestPermissions(
this@MapsActivity,
arrayOf(Manifest.permission.ACCESS_FINE_LOCATION),
MY_PERMISSIONS_REQUEST_LOCATION
)
}
.create()
.show()
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(
this,
arrayOf(Manifest.permission.ACCESS_FINE_LOCATION),
MY_PERMISSIONS_REQUEST_LOCATION
)
}
}
}
override fun onRequestPermissionsResult(
requestCode: Int,
permissions: Array<String>, grantResults: IntArray
) {
when (requestCode) {
MY_PERMISSIONS_REQUEST_LOCATION -> {
// If request is cancelled, the result arrays are empty.
if (grantResults.isNotEmpty() && 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
) {
mFusedLocationClient?.requestLocationUpdates(
mLocationRequest,
mLocationCallback,
Looper.myLooper()
)
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
}
companion object {
val MY_PERMISSIONS_REQUEST_LOCATION = 99
}
}
Java
这是完整的 Java Activity 类:
public class MapsActivity extends AppCompatActivity
implements OnMapReadyCallback {
GoogleMap mGoogleMap;
SupportMapFragment mapFrag;
LocationRequest mLocationRequest;
Location mLastLocation;
Marker mCurrLocationMarker;
FusedLocationProviderClient mFusedLocationClient;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
getSupportActionBar().setTitle("Map Location Activity");
mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
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 (mFusedLocationClient != null) {
mFusedLocationClient.removeLocationUpdates(mLocationCallback);
}
}
@Override
public void onMapReady(GoogleMap googleMap) {
mGoogleMap = googleMap;
mGoogleMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(120000); // two minute interval
mLocationRequest.setFastestInterval(120000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
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
mFusedLocationClient.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper());
mGoogleMap.setMyLocationEnabled(true);
} else {
//Request Location Permission
checkLocationPermission();
}
}
else {
mFusedLocationClient.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper());
mGoogleMap.setMyLocationEnabled(true);
}
}
LocationCallback mLocationCallback = new LocationCallback() {
@Override
public void onLocationResult(LocationResult locationResult) {
List<Location> locationList = locationResult.getLocations();
if (locationList.size() > 0) {
//The last location in the list is the newest
Location location = locationList.get(locationList.size() - 1);
Log.i("MapsActivity", "Location: " + location.getLatitude() + " " + location.getLongitude());
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(MapsActivity.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) {
mFusedLocationClient.requestLocationUpdates(mLocationRequest, mLocationCallback, Looper.myLooper());
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_maps.xml:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".map.MapsActivity">
<fragment android:id="@+id/map"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".map.MapsActivity"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
android:name="com.google.android.gms.maps.SupportMapFragment"/>
</androidx.constraintlayout.widget.ConstraintLayout>
将提示用户接受位置权限:
位置将在应用启动时更新,每两分钟更新一次:
关于 AndroidX 的额外说明
如果您使用的是 AndroidX,you might need to add these lines到您的 gradle.properties
文件中(参见 here 了解更多信息):
android.useAndroidX=true
android.enableJetifier=true
关于java - 如何使用 FusedLocationProviderClient 在 GoogleMap 中获取当前位置,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/44992014/
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