無法在Google地圖中獲取當前位置

Question

我無法通過以下方式獲取當前位置。這些代碼是從Web上的一些教程中學到的，我不知道標記仍然處於相同位置。我是android新手，請幫助T_T

這是MapsActivity.java中的代碼。

import android.content.IntentSender; 
import android.location.Location; 
import android.os.Bundle; 
import android.support.v4.app.FragmentActivity; 
import android.util.Log; 

import com.google.android.gms.common.ConnectionResult; 
import com.google.android.gms.common.api.GoogleApiClient; 
import com.google.android.gms.location.LocationListener; 
import com.google.android.gms.location.LocationRequest; 
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.SupportMapFragment; 
import com.google.android.gms.maps.model.LatLng; 
import com.google.android.gms.maps.model.MarkerOptions; 

public class MapsActivity extends FragmentActivity implements 
    GoogleApiClient.ConnectionCallbacks, 
    GoogleApiClient.OnConnectionFailedListener, 
    LocationListener { 

public static final String TAG = MapsActivity.class.getSimpleName(); 

/* 
* 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; 

private GoogleMap mMap; // Might be null if Google Play services APK is not available. 

private GoogleApiClient mGoogleApiClient; 
private LocationRequest mLocationRequest; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_maps); 
    setUpMapIfNeeded(); 

    if (mGoogleApiClient == null) { 
     mGoogleApiClient = new GoogleApiClient.Builder(this) 
       .addConnectionCallbacks(this) 
       .addOnConnectionFailedListener(this) 
       .addApi(LocationServices.API) 
       .build(); 
    } 

    // Create the LocationRequest object 
    mLocationRequest = LocationRequest.create() 
      .setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY) 
      .setInterval(10 * 1000)  // 10 seconds, in milliseconds 
      .setFastestInterval(1 * 1000); // 1 second, in milliseconds 
} 

@Override 
protected void onResume() { 
    super.onResume(); 
    setUpMapIfNeeded(); 
    mGoogleApiClient.connect(); 
} 

@Override 
protected void onPause() { 
    super.onPause(); 

    if (mGoogleApiClient.isConnected()) { 
     LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this); 
     mGoogleApiClient.disconnect(); 
    } 
} 

/** 
* Sets up the map if it is possible to do so (i.e., the Google Play services APK is correctly 
* installed) and the map has not already been instantiated.. This will ensure that we only ever 
* call {@link #setUpMap()} once when {@link #mMap} is not null. 
* <p/> 
* If it isn't installed {@link SupportMapFragment} (and 
* {@link com.google.android.gms.maps.MapView MapView}) will show a prompt for the user to 
* install/update the Google Play services APK on their device. 
* <p/> 
* A user can return to this FragmentActivity after following the prompt and correctly 
* installing/updating/enabling the Google Play services. Since the FragmentActivity may not 
* have been completely destroyed during this process (it is likely that it would only be 
* stopped or paused), {@link #onCreate(Bundle)} may not be called again so we should call this 
* method in {@link #onResume()} to guarantee that it will be called. 
*/ 
private void setUpMapIfNeeded() { 
    // Do a null check to confirm that we have not already instantiated the map. 
    if (mMap == null) { 
     // Try to obtain the map from the SupportMapFragment. 
     mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)) 
       .getMap(); 
     // Check if we were successful in obtaining the map. 
     if (mMap != null) { 
      setUpMap(); 
     } 
    } 
} 

/** 
* This is where we can add markers or lines, add listeners or move the camera. In this case, we 
* just add a marker near Africa. 
* <p/> 
* This should only be called once and when we are sure that {@link #mMap} is not null. 
*/ 
private void setUpMap() { 
    mMap.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker")); 

} 

private void handleNewLocation(Location location) { 
    Log.d(TAG, location.toString()); 

    double currentLatitude = location.getLatitude(); 
    double currentLongitude = location.getLongitude(); 

    LatLng latLng = new LatLng(currentLatitude, currentLongitude); 

    mMap.addMarker(new MarkerOptions().position(new LatLng(currentLatitude, currentLongitude)).title("Current Location")); 
    MarkerOptions options = new MarkerOptions() 
      .position(latLng) 
      .title("I am here!"); 
    mMap.addMarker(options); 
    mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng)); 
} 

@Override 
public void onConnected(Bundle bundle) { 

    Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient); 
    if (location == null) { 
     LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this); 
    } 
    else { 
     handleNewLocation(location); 
    } 
} 

@Override 
public void onConnectionSuspended(int i) { 
    Log.i(TAG, "Location services suspended. Please reconnect."); 
} 

@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 { 
     /* 
     * If no resolution is available, display a dialog to the 
     * user with the error. 
     */ 
     Log.i(TAG, "Location services connection failed with code " + connectionResult.getErrorCode()); 
    } 
} 

@Override 
public void onLocationChanged(Location location) { 
    handleNewLocation(location); 
} 

}

而且這是在Android清單中的代碼。

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
package="com.example.tanghoiyan.mapapp"> 


<!-- 
    The ACCESS_COARSE/FINE_LOCATION permissions are not required to use 
    Google Maps Android API v2, but you must specify either coarse or fine 
    location permissions for the 'MyLocation' functionality. 
--> 

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> 
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /> 

<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> 
</manifest> 

Answer 1

請在清單中添加

<uses-permission android:name="android.permission.INTERNET" 
<uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" /> 
<permission android:name="com.example.tanghoiyan.mapapp.permission.MAPS_RECEIVE" android:protectionLevel="signature"/> 
<uses-feature android:glEsVersion="0x00020000" android:required="true" /> 

，然後再試一次。

注意：如果您使用Android 6. +您可以實時檢查位置權限。

Answer 2

將.setNumUpdates(1);添加到您的mLocationRequest，因此您只會收到一次位置。
以下代碼檢查GPS位置更新的權限需求，並開始請求您已有的內容。我正在使用按鈕單擊事件上的代碼，它的工作方式與預期相同，當然，第一次使用該位置需要一些時間，但這是GPS。

protected void startLocationUpdates() { 
    if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) 
      == PackageManager.PERMISSION_GRANTED) { 
     LocationServices.FusedLocationApi.requestLocationUpdates(
       mGoogleApiClient, mLocationRequest, this); 
    } 
} 

你檢查，如果你得到一個位置還是空的onConnected功能？