我正在使用Android中的位置服务进行测试,我严格遵循开发人员的说明(此处:Google dev. link)了解如何执行此操作,但没有运气。在我的布局中,我只有两个TextView来显示Location对象的纬度和经度。我应该提一下,我正在使用启用了GPS的Genymotion VM。
这是我在MainActivity中的代码:
package criminalintent.android.bignerdranch.com.testgetlocation;
import android.app.Activity;
import android.location.Location;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.drive.Drive;
import com.google.android.gms.location.LocationServices;
public class MainActivity extends Activity implements
GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener {
GoogleApiClient mGoogleApiClient;
private TextView mLatitudeText;
private TextView mLongitudeText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mLatitudeText= (TextView) findViewById(R.id.latitudeTextView);
mLongitudeText = (TextView) findViewById(R.id.longitudeTextView);
buildGoogleApiClient();
}
protected synchronized void buildGoogleApiClient() {
Toast.makeText(this,"buildGoogleApiClient",Toast.LENGTH_SHORT).show();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
@Override
public void onConnected(Bundle bundle) {
Toast.makeText(this,"onConnected",Toast.LENGTH_SHORT).show();
Location mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
if (mLastLocation != null) {
mLatitudeText.setText(String.valueOf(mLastLocation.getLatitude()));
mLongitudeText.setText(String.valueOf(mLastLocation.getLongitude()));
}
}
@Override
public void onConnectionSuspended(int i) {
Toast.makeText(this,"onConnectionSuspended",Toast.LENGTH_SHORT).show();
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
Toast.makeText(this,"onConnectionFailed",Toast.LENGTH_SHORT).show();
}
}
我已添加了在清单文件中获取位置服务的权限:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="criminalintent.android.bignerdranch.com.testgetlocation" >
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
这是我的模块build.gradle文件代码:
apply plugin: 'com.android.application'
android {
compileSdkVersion 22
buildToolsVersion "21.1.2"
defaultConfig {
applicationId "criminalintent.android.bignerdranch.com.testgetlocation"
minSdkVersion 14
targetSdkVersion 22
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:appcompat-v7:22.1.1'
compile 'com.google.android.gms:play-services:7.3.0'
}
答案 0 :(得分:2)
你错过了连接电话。
致电connect()
后,在onCreate()
中将来电添加到buildGoogleApiClient()
:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mLatitudeText= (TextView) findViewById(R.id.latitudeTextView);
mLongitudeText = (TextView) findViewById(R.id.longitudeTextView);
buildGoogleApiClient();
mGoogleApiClient.connect(); //add this here
}
请注意,即使使用此修复程序,对getLastLocation()
的调用也会很有可能为您提供空位。
如果你得到一个空位,我建议你注册一个监听器,看看this answer有关如何做到这一点的信息。
编辑:由于我已经运行了代码,因此我继续添加了一个位置监听器。请注意,在此代码中,我在第一次removeLocationUpdates()
回调发生后立即添加了对onLocationChanged()
的调用,仅作为示例:
import android.os.Bundle;
import android.app.Activity;
import android.location.Location;
import android.widget.TextView;
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.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.location.LocationListener;
public class MainActivity extends Activity implements
GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
LocationRequest mLocationRequest;
GoogleApiClient mGoogleApiClient;
private TextView mLatitudeText;
private TextView mLongitudeText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mLatitudeText= (TextView) findViewById(R.id.latitudeTextView);
mLongitudeText = (TextView) findViewById(R.id.longitudeTextView);
buildGoogleApiClient();
mGoogleApiClient.connect(); //add this here
}
protected synchronized void buildGoogleApiClient() {
Toast.makeText(this,"buildGoogleApiClient",Toast.LENGTH_SHORT).show();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
@Override
public void onConnected(Bundle bundle) {
Toast.makeText(this,"onConnected",Toast.LENGTH_SHORT).show();
Location mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
if (mLastLocation != null) {
mLatitudeText.setText(String.valueOf(mLastLocation.getLatitude()));
mLongitudeText.setText(String.valueOf(mLastLocation.getLongitude()));
}
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(10000); //10 seconds
mLocationRequest.setFastestInterval(5000); //5 seconds
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
mLocationRequest.setSmallestDisplacement(1); //1 meter
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
@Override
public void onConnectionSuspended(int i) {
Toast.makeText(this,"onConnectionSuspended",Toast.LENGTH_SHORT).show();
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
Toast.makeText(this,"onConnectionFailed",Toast.LENGTH_SHORT).show();
}
@Override
public void onLocationChanged(Location location) {
Toast.makeText(this,"Location Changed",Toast.LENGTH_SHORT).show();
mLatitudeText.setText(String.valueOf(location.getLatitude()));
mLongitudeText.setText(String.valueOf(location.getLongitude()));
//If you only need one location, unregister the listener
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
}
另请注意,您应将此添加到应用程序标记内的AndroidManifest.xml中:
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />