如何在Google Maps Android API v2中直接将相机移到当前位置？
没有点击任何button，如何直接获取当前位置，并将相机移动到它。
另外，我发现地图右上方有一个button。 当点击它，它会去当前的位置。 点击该button时如何获取返回的位置？
确保你有这些权限：
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/> <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/> 然后进行一些活动并注册一个LocationListener
package com.example.location; import android.content.Context; import android.location.Location; import android.location.LocationListener; import android.location.LocationManager; import android.os.Bundle; import android.view.View; import com.actionbarsherlock.app.SherlockFragmentActivity; import com.google.android.gms.maps.CameraUpdate; import com.google.android.gms.maps.CameraUpdateFactory; import com.google.android.gms.maps.GoogleMap; import com.google.android.gms.maps.SupportMapFragment; import com.google.android.gms.maps.model.LatLng; public class LocationActivity extends SherlockFragmentActivity implements LocationListener { private GoogleMap map; private LocationManager locationManager; private static final long MIN_TIME = 400; private static final float MIN_DISTANCE = 1000; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.map); map = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)).getMap(); locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, MIN_TIME, MIN_DISTANCE, this); //You can also use LocationManager.GPS_PROVIDER and LocationManager.PASSIVE_PROVIDER } @Override public void onLocationChanged(Location location) { LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude()); CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(latLng, 10); map.animateCamera(cameraUpdate); locationManager.removeUpdates(this); } @Override public void onStatusChanged(String provider, int status, Bundle extras) { } @Override public void onProviderEnabled(String provider) { } @Override public void onProviderDisabled(String provider) { } }
map.xml
<?xml version="1.0" encoding="utf-8"?> <fragment xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/map" android:layout_width="match_parent" android:layout_height="match_parent" class="com.google.android.gms.maps.SupportMapFragment"/>
上面的答案不是根据谷歌文档在Google API a v2中提到的位置跟踪。
我只是按照正式的教程，结束了这个课程，获取当前的位置，并在地图上居中。
您可以扩展此类以使LocationReciever具有定期位置更新。 我只是在api 7级上执行这个代码
http://developer.android.com/training/location/retrieve-current.html
在这里。
import android.app.Activity; import android.app.Dialog; import android.content.Intent; import android.content.IntentSender; import android.location.Location; import android.os.Bundle; import android.support.v4.app.DialogFragment; import android.support.v4.app.FragmentActivity; import android.util.Log; import android.widget.Toast; import com.google.android.gms.common.ConnectionResult; import com.google.android.gms.common.GooglePlayServicesClient; import com.google.android.gms.common.GooglePlayServicesUtil; import com.google.android.gms.location.LocationClient; import com.google.android.gms.maps.CameraUpdate; import com.google.android.gms.maps.CameraUpdateFactory; import com.google.android.gms.maps.GoogleMap; import com.google.android.gms.maps.GoogleMap.OnMapLongClickListener; import com.google.android.gms.maps.SupportMapFragment; import com.google.android.gms.maps.model.LatLng; public class MainActivity extends FragmentActivity implements GooglePlayServicesClient.ConnectionCallbacks, GooglePlayServicesClient.OnConnectionFailedListener{ private SupportMapFragment mapFragment; private GoogleMap map; private LocationClient mLocationClient; /* * Define a request code to send to Google Play services * This code is returned in Activity.onActivityResult */ private final static int CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000; // Define a DialogFragment that displays the error dialog public static class ErrorDialogFragment extends DialogFragment { // Global field to contain the error dialog private Dialog mDialog; // Default constructor. Sets the dialog field to null public ErrorDialogFragment() { super(); mDialog = null; } // Set the dialog to display public void setDialog(Dialog dialog) { mDialog = dialog; } // Return a Dialog to the DialogFragment. @Override public Dialog onCreateDialog(Bundle savedInstanceState) { return mDialog; } } @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main_activity); mLocationClient = new LocationClient(this, this, this); mapFragment = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)); map = mapFragment.getMap(); map.setMyLocationEnabled(true); } /* * Called when the Activity becomes visible. */ @Override protected void onStart() { super.onStart(); // Connect the client. if(isGooglePlayServicesAvailable()){ mLocationClient.connect(); } } /* * Called when the Activity is no longer visible. */ @Override protected void onStop() { // Disconnecting the client invalidates it. mLocationClient.disconnect(); super.onStop(); } /* * Handle results returned to the FragmentActivity * by Google Play services */ @Override protected void onActivityResult( int requestCode, int resultCode, Intent data) { // Decide what to do based on the original request code switch (requestCode) { case CONNECTION_FAILURE_RESOLUTION_REQUEST: /* * If the result code is Activity.RESULT_OK, try * to connect again */ switch (resultCode) { case Activity.RESULT_OK: mLocationClient.connect(); break; } } } private boolean isGooglePlayServicesAvailable() { // Check that Google Play services is available int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this); // If Google Play services is available if (ConnectionResult.SUCCESS == resultCode) { // In debug mode, log the status Log.d("Location Updates", "Google Play services is available."); return true; } else { // Get the error dialog from Google Play services Dialog errorDialog = GooglePlayServicesUtil.getErrorDialog( resultCode, this, CONNECTION_FAILURE_RESOLUTION_REQUEST); // If Google Play services can provide an error dialog if (errorDialog != null) { // Create a new DialogFragment for the error dialog ErrorDialogFragment errorFragment = new ErrorDialogFragment(); errorFragment.setDialog(errorDialog); errorFragment.show(getSupportFragmentManager(), "Location Updates"); } return false; } } /* * Called by Location Services when the request to connect the * client finishes successfully. At this point, you can * request the current location or start periodic updates */ @Override public void onConnected(Bundle dataBundle) { // Display the connection status Toast.makeText(this, "Connected", Toast.LENGTH_SHORT).show(); Location location = mLocationClient.getLastLocation(); LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude()); CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(latLng, 17); map.animateCamera(cameraUpdate); } /* * Called by Location Services if the connection to the * location client drops because of an error. */ @Override public void onDisconnected() { // Display the connection status Toast.makeText(this, "Disconnected. Please re-connect.", Toast.LENGTH_SHORT).show(); } /* * Called by Location Services if the attempt to * Location Services fails. */ @Override public void onConnectionFailed(ConnectionResult connectionResult) { /* * Google Play services can resolve some errors it detects. * If the error has a resolution, try sending an Intent to * start a Google Play services activity that can resolve * error. */ if (connectionResult.hasResolution()) { try { // Start an Activity that tries to resolve the error connectionResult.startResolutionForResult( this, CONNECTION_FAILURE_RESOLUTION_REQUEST); /* * Thrown if Google Play services canceled the original * PendingIntent */ } catch (IntentSender.SendIntentException e) { // Log the error e.printStackTrace(); } } else { Toast.makeText(getApplicationContext(), "Sorry. Location services not available to you", Toast.LENGTH_LONG).show(); } } }
我正在解释如何获取当前位置，并假设已经实现了map-v2，直接移动到相机到当前位置。 有关更多详情，请参阅官方文档 。
在gradle中添加位置服务
implementation "com.google.android.gms:play-services-location:11.0.1"
在清单文件中添加位置权限
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
确保你要求RunTimePermission。 我正在使用Ask-Permission 。 它易于使用。
现在引用下面的代码来获取当前位置并将其显示在地图上。
private FusedLocationProviderClient mFusedLocationProviderClient; @Override public void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); mFusedLocationProviderClient = LocationServices .getFusedLocationProviderClient(getActivity()); } private void getDeviceLocation() { try { if (mLocationPermissionGranted) { Task<Location> locationResult = mFusedLocationProviderClient.getLastLocation(); locationResult.addOnCompleteListener(new OnCompleteListener<Location>() { @Override public void onComplete(@NonNull Task<Location> task) { if (task.isSuccessful()) { // Set the map's camera position to the current location of the device. Location location = task.getResult(); LatLng currentLatLng = new LatLng(location.getLatitude(), location.getLongitude()); CameraUpdate update = CameraUpdateFactory.newLatLngZoom(currentLatLng, DEFAULT_ZOOM); googleMap.moveCamera(update); } } }); } } catch (SecurityException e) { Log.e("Exception: %s", e.getMessage()); } }
当用户授予以上getDeviceLocation()方法的位置权限调用
private void updateLocationUI() { if (googleMap == null) { return; } try { if (mLocationPermissionGranted) { googleMap.setMyLocationEnabled(true); googleMap.getUiSettings().setMyLocationButtonEnabled(true); getDeviceLocation(); } else { googleMap.setMyLocationEnabled(false); googleMap.getUiSettings().setMyLocationButtonEnabled(false); } } catch (SecurityException e) { Log.e("Exception: %s", e.getMessage()); } }
