我首先在Google地图更新后才能在我的应用中获取当前位置，而如果我不更新Google地图，我的应用无法获取当前位置。这是我的Java代码：
MapsActivity.java
import android.location.Location;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageButton;
import android.widget.Toast;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
public class MapsActivity extends FragmentActivity implements
OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
GoogleMap.OnMarkerDragListener,
GoogleMap.OnMapLongClickListener,
View.OnClickListener{
//Our Map
private GoogleMap mMap;
//To store longitude and latitude from map
private double longitude;
private double latitude;
//Buttons
private ImageButton buttonSave;
private ImageButton buttonCurrent;
private ImageButton buttonView;
//Google ApiClient
private GoogleApiClient googleApiClient;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
// Obtain the SupportMapFragment and get notified when the map is ready to be used.
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
//Initializing googleapi client
googleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
//Initializing views and adding onclick listeners
buttonSave = (ImageButton) findViewById(R.id.buttonSave);
buttonCurrent = (ImageButton) findViewById(R.id.buttonCurrent);
buttonView = (ImageButton) findViewById(R.id.buttonView);
buttonSave.setOnClickListener(this);
buttonCurrent.setOnClickListener(this);
buttonView.setOnClickListener(this);
}
@Override
protected void onStart() {
googleApiClient.connect();
super.onStart();
}
@Override
protected void onStop() {
googleApiClient.disconnect();
super.onStop();
}
//Getting current location
private void getCurrentLocation() {
mMap.clear();
//Creating a location object
Location location = LocationServices.FusedLocationApi.getLastLocation(googleApiClient);
if (location != null) {
//Getting longitude and latitude
longitude = location.getLongitude();
latitude = location.getLatitude();
//moving the map to location
moveMap();
}
}
//Function to move the map
private void moveMap() {
//String to display current latitude and longitude
String msg = latitude + ", "+longitude;
//Creating a LatLng Object to store Coordinates
LatLng latLng = new LatLng(latitude, longitude);
//Adding marker to map
mMap.addMarker(new MarkerOptions()
.position(latLng) //setting position
.draggable(true) //Making the marker draggable
.title("Current Location")); //Adding a title
//Moving the camera
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
//Animating the camera
mMap.animateCamera(CameraUpdateFactory.zoomTo(15));
//Displaying current coordinates in toast
Toast.makeText(this, msg, Toast.LENGTH_LONG).show();
}
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
LatLng latLng = new LatLng(-34, 151);
mMap.addMarker(new MarkerOptions().position(latLng).draggable(true));
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mMap.setOnMarkerDragListener(this);
mMap.setOnMapLongClickListener(this);
}
@Override
public void onConnected(Bundle bundle) {
getCurrentLocation();
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
}
@Override
public void onMapLongClick(LatLng latLng) {
//Clearing all the markers
mMap.clear();
//Adding a new marker to the current pressed position
mMap.addMarker(new MarkerOptions()
.position(latLng)
.draggable(true));
}
@Override
public void onMarkerDragStart(Marker marker) {
}
@Override
public void onMarkerDrag(Marker marker) {
}
@Override
public void onMarkerDragEnd(Marker marker) {
//Getting the coordinates
latitude = marker.getPosition().latitude;
longitude = marker.getPosition().longitude;
//Moving the map
moveMap();
}
@Override
public void onClick(View v) {
if(v == buttonCurrent){
getCurrentLocation();
moveMap();
}}}
这是我的清单。
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.takecare">
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<!--
The API key for Google Maps-based APIs is defined as a string resource.
(See the file "res/values/google_maps_api.xml").
Note that the API key is linked to the encryption key used to sign the APK.
You need a different API key for each encryption key, including the release key that is used to
sign the APK for publishing.
You can define the keys for the debug and release targets in src/debug/ and src/release/.
-->
<meta-data
android:name="com.google.android.geo.API_KEY"
android:value="@string/google_maps_key" />
<activity
android:name=".MapsActivity"
android:label="@string/title_activity_maps">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
这是My App Gradle依赖项
compile 'com.android.support:appcompat-v7:24.1.1'
compile 'com.android.support:design:24.1.1'
compile 'com.android.support:support-v4:24.1.1'
compile 'com.google.android.gms:play-services:9.4.0'
compile 'com.google.android.gms:play-services-location:9.4.0'
答案 0 :(得分：0)
你写错了这些代码行
此代码用于获取当前lat和long数据
longitude = location.getLongitude();
latitude = location.getLatitude();
并将此数据设置为在地图上设置
mMap = googleMap;
LatLng latLng = new LatLng(-34, 151);
mMap.addMarker(new MarkerOptions().position(latLng).draggable(true));
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mMap.setOnMarkerDragListener(this);
mMap.setOnMapLongClickListener(this);
更新您的位置后，您将设置此位置
mMap.addMarker(new MarkerOptions()
.position(latLng)
.draggable(true));
where as your data is on latLng -34, 151
你没有在地图上获得更新数据只是通过使用这些代码行获取最新数据
LatLng latLng = new LatLng(location.getLongitude(),location.getLatitude());
我没有检查你的gradle或清单请检查你的结尾。
可能这段代码会帮助你）;