我在android应用程序中实现了地理围栏。我跟着this https://developer.android.com/training/location/geofencing.html在应用程序中实施“地理围栏”的链接。我正在使用“Retrofit”库来调用“HTTP”请求。
应用程序具有以下权限：
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
这是我的“IntentService”代码：
public class GeofenceService extends IntentService
{
private static final String TAG = GeofenceService.class.getName();
public static final int GEOFENCE_NOTIFICATION_ID = 0;
public GeofenceService() {
super(TAG);
}
@Override
protected void onHandleIntent(Intent intent) {
// Retrieve the Geofencing intent
GeofencingEvent geofencingEvent = GeofencingEvent.fromIntent(intent);
createLoggerFile();
// Handling errors
if ( geofencingEvent.hasError() ) {
String errorMsg = getErrorString(geofencingEvent.getErrorCode() );
Logger.Important(true, TAG, "onHandleIntent() :: errorMessage : "+errorMsg );
return;
}
// Retrieve GeofenceTrasition
int geoFenceTransition = geofencingEvent.getGeofenceTransition();
// Check if the transition type
if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_ENTER ||
geoFenceTransition == Geofence.GEOFENCE_TRANSITION_EXIT ||
geoFenceTransition == Geofence.GEOFENCE_TRANSITION_DWELL)
{
Log.d(TAG, "onHandleIntent() :: geoFenceTransition : " + geoFenceTransition);
// Get the geofence that were triggered
List<Geofence> triggeringGeofences = geofencingEvent.getTriggeringGeofences();
// Create a detail message with Geofences received
String geofenceTransitionDetails = getGeofenceTrasitionDetails(geoFenceTransition, triggeringGeofences );
// Send notification details as a String
sendNotification( geofenceTransitionDetails );
}
}
// Create a detail message with Geofences received
private String getGeofenceTrasitionDetails(int geoFenceTransition, List<Geofence> triggeringGeofences) {
// get the ID of each geofence triggered
ArrayList<String> triggeringGeofencesList = new ArrayList<>();
for ( Geofence geofence : triggeringGeofences ) {
triggeringGeofencesList.add( geofence.getRequestId() );
pingGoogle(); // here is I am pinging google
callingHttpRequest(); // calling Http request. Also I called this request through application class, but still it is not worked in background.
}
String status = null;
if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_ENTER )
status = "Entering ";
else if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_EXIT )
status = "Exiting ";
else if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_DWELL )
status = "Staying ";
return status + TextUtils.join( ", ", triggeringGeofencesList);
}
// Send a notification
private void sendNotification( String msg ) {
Log.d( TAG, "sendNotification: " + msg );
// Intent to start the main Activity
Intent notificationIntent = new Intent(getApplicationContext(), DrawerActivity.class);;
TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
stackBuilder.addParentStack(DrawerActivity.class);
stackBuilder.addNextIntent(notificationIntent);
PendingIntent notificationPendingIntent = stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);
// Creating and sending Notification
NotificationManager notificatioMng =
(NotificationManager) getSystemService( Context.NOTIFICATION_SERVICE );
notificatioMng.notify(
GEOFENCE_NOTIFICATION_ID,
createNotification(msg, notificationPendingIntent));
}
// Create a notification
private Notification createNotification(String msg, PendingIntent notificationPendingIntent) {
NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this);
notificationBuilder
.setSmallIcon(R.drawable.ic_phi_notification_logo)
.setLargeIcon(BitmapFactory.decodeResource(getResources(), R.drawable.geo))
.setColor(Converter.getColor(getApplicationContext(), R.color.default_pure_cyan))
.setContentTitle(JsonKey.TRIGGER)
.setContentText(msg)
.setContentIntent(notificationPendingIntent)
.setDefaults(Notification.DEFAULT_LIGHTS | Notification.DEFAULT_VIBRATE | Notification.DEFAULT_SOUND)
.setAutoCancel(true);
return notificationBuilder.build();
}
// Handle errors
private static String getErrorString(int errorCode) {
switch (errorCode) {
case GeofenceStatusCodes.GEOFENCE_NOT_AVAILABLE:
return "GeoFence not available";
case GeofenceStatusCodes.GEOFENCE_TOO_MANY_GEOFENCES:
return "Too many GeoFences";
case GeofenceStatusCodes.GEOFENCE_TOO_MANY_PENDING_INTENTS:
return "Too many pending intents";
default:
return "Unknown error.";
}
}
private void callingHttpRequest() {
HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
OkHttpClient client = new OkHttpClient.Builder()
.addInterceptor(interceptor)
.readTimeout(10, TimeUnit.SECONDS)
.connectTimeout(10 / 2, TimeUnit.SECONDS)
.sslSocketFactory(sslSocketFactory().getSocketFactory())
.build();
Gson gson = new GsonBuilder()
.setLenient()
.create();
Retrofit retrofit = new Retrofit.Builder()
.baseUrl(url)
.client(client)
.addConverterFactory(GsonConverterFactory.create(gson))
.build();
API api = retrofit.create(***.class);
Call<ResponseBody> req = api.callGeofencingTrigger(***);
req.enqueue(new Callback<ResponseBody>() {
@Override
public void onResponse(Call<ResponseBody> call, retrofit2.Response<ResponseBody> response) {
try {
String string = response.body().string();
Log.d (TAG, "onResponse() :: success");
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public void onFailure(Call<ResponseBody> call, Throwable t) {
t.printStackTrace();
Log.d (TAG, "onFailure() :: t : "t.getMessage());
}
});
}
}
每当设备触发地理围栏时，它都会正常工作，并在应用程序处于后台或前台（进入/停留/离开）时或即使用户从最近的任务中杀死应用程序时发出适当的触发通知。当我调用 HTTP 请求时，当应用程序位于前台时，它可以正常工作并在日志上打印成功。
onResponse() :: success
但是，当应用程序从最近的任务中终止并且设备收到任何地理围栏触发器（进入/停留/离开）时，HTTP 请求将无法正确执行。它给 ：
onFailure() :: t :
</br>java.net.UnknownHostException: Unable to resolve host
"host_name": No address associated with hostname
其中 host_name 是服务器地址。
I ping google http://www.google.com或来自后台服务的 8.8.8.8 ip。仍然面临同样的问题。当应用程序位于前台时，这件事也可以正常工作，但在杀死应用程序后，它就不起作用了。
那么，为什么会出现这个错误呢？当应用程序不在最近的任务中时，网络通信是否不会调用？
我尝试了以下事情。从@Xavier 和@Stevensen 得到答案后
我在用firebase-jobscheduler https://github.com/firebase/firebase-jobdispatcher-android在我的通话申请中HTTP要求。这是我的代码：
在我的清单中，我添加了以下服务：
<service
android:exported="false"
android:name="com.****.service.TriggerJobService">
<intent-filter>
<action android:name="com.firebase.jobdispatcher.ACTION_EXECUTE"/>
</intent-filter>
</service>
这是我修改后的 GeofenceService 类。我刚刚删除了callingHttpRequest()并通过调用添加了计划作业scheduleJob()函数于getGeofenceTrasitionDetails()功能。并且代码与原样相同。
public class GeofenceService extends IntentService
{
private static final String TAG = GeofenceService.class.getName();
public static final int GEOFENCE_NOTIFICATION_ID = 0;
public GeofenceService() {
super(TAG);
}
@Override
protected void onHandleIntent(Intent intent) {
// Retrieve the Geofencing intent
GeofencingEvent geofencingEvent = GeofencingEvent.fromIntent(intent);
createLoggerFile();
// Handling errors
if ( geofencingEvent.hasError() ) {
String errorMsg = getErrorString(geofencingEvent.getErrorCode() );
Logger.Important(true, TAG, "onHandleIntent() :: errorMessage : "+errorMsg );
return;
}
// Retrieve GeofenceTrasition
int geoFenceTransition = geofencingEvent.getGeofenceTransition();
// Check if the transition type
if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_ENTER ||
geoFenceTransition == Geofence.GEOFENCE_TRANSITION_EXIT ||
geoFenceTransition == Geofence.GEOFENCE_TRANSITION_DWELL)
{
Log.d(TAG, "onHandleIntent() :: geoFenceTransition : " + geoFenceTransition);
// Get the geofence that were triggered
List<Geofence> triggeringGeofences = geofencingEvent.getTriggeringGeofences();
// Create a detail message with Geofences received
String geofenceTransitionDetails = getGeofenceTrasitionDetails(geoFenceTransition, triggeringGeofences );
// Send notification details as a String
sendNotification( geofenceTransitionDetails );
}
}
// Create a detail message with Geofences received
private String getGeofenceTrasitionDetails(int geoFenceTransition, List<Geofence> triggeringGeofences) {
// get the ID of each geofence triggered
ArrayList<String> triggeringGeofencesList = new ArrayList<>();
for ( Geofence geofence : triggeringGeofences ) {
triggeringGeofencesList.add( geofence.getRequestId() );
scheduleJob(); // <code>**Here I schedule job**</code>
}
String status = null;
if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_ENTER )
status = "Entering ";
else if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_EXIT )
status = "Exiting ";
else if ( geoFenceTransition == Geofence.GEOFENCE_TRANSITION_DWELL )
status = "Staying ";
return status + TextUtils.join( ", ", triggeringGeofencesList);
}
// Send a notification
private void sendNotification( String msg ) {
Log.d( TAG, "sendNotification: " + msg );
// Intent to start the main Activity
Intent notificationIntent = new Intent(getApplicationContext(), DrawerActivity.class);;
TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
stackBuilder.addParentStack(DrawerActivity.class);
stackBuilder.addNextIntent(notificationIntent);
PendingIntent notificationPendingIntent = stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);
// Creating and sending Notification
NotificationManager notificatioMng =
(NotificationManager) getSystemService( Context.NOTIFICATION_SERVICE );
notificatioMng.notify(
GEOFENCE_NOTIFICATION_ID,
createNotification(msg, notificationPendingIntent));
}
// Create a notification
private Notification createNotification(String msg, PendingIntent notificationPendingIntent) {
NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this);
notificationBuilder
.setSmallIcon(R.drawable.ic_phi_notification_logo)
.setLargeIcon(BitmapFactory.decodeResource(getResources(), R.drawable.geo))
.setColor(Converter.getColor(getApplicationContext(), R.color.default_pure_cyan))
.setContentTitle(JsonKey.TRIGGER)
.setContentText(msg)
.setContentIntent(notificationPendingIntent)
.setDefaults(Notification.DEFAULT_LIGHTS | Notification.DEFAULT_VIBRATE | Notification.DEFAULT_SOUND)
.setAutoCancel(true);
return notificationBuilder.build();
}
// Handle errors
private static String getErrorString(int errorCode) {
switch (errorCode) {
case GeofenceStatusCodes.GEOFENCE_NOT_AVAILABLE:
return "GeoFence not available";
case GeofenceStatusCodes.GEOFENCE_TOO_MANY_GEOFENCES:
return "Too many GeoFences";
case GeofenceStatusCodes.GEOFENCE_TOO_MANY_PENDING_INTENTS:
return "Too many pending intents";
default:
return "Unknown error.";
}
}
private void scheduleJob()
{
Bundle bundle = new Bundle();
FirebaseJobDispatcher dispatcher = new FirebaseJobDispatcher(new GooglePlayDriver(getApplicationContext()));
Job.Builder builder = dispatcher.newJobBuilder();
builder.setExtras(bundle);
builder.setTag(requestId);
builder.setService(TriggerJobService.class);
builder.setTrigger(Trigger.executionWindow(10, 30));
builder.setReplaceCurrent(true);
builder.addConstraint(Constraint.DEVICE_CHARGING);
builder.addConstraint(Constraint.ON_ANY_NETWORK);
builder.addConstraint(Constraint.ON_UNMETERED_NETWORK);
dispatcher.mustSchedule(builder.build());
}
}
这是我的 TriggerJobService 代码：
public class TriggerJobService extends JobService
{
private static final String TAG = TriggerJobService.class.getName();
private int count;
@Override
public boolean onStartJob(JobParameters job)
{
Log.d(TAG, "onStartJob() :: " + job.getTag());
// Return true as there's more work to be done with this job.
//TODO have to send request to cloud
Bundle bundle = job.getExtras();
callingHttpRequest(); // here is I am calling 'HTTP' request
return true;
}
@Override
public boolean onStopJob(JobParameters job)
{
Log.d(TAG, "onStopJob() :: " + job.getTag());
// Return false to drop the job.
return false;
}
private void callingHttpRequest() {
HttpLoggingInterceptor interceptor = new HttpLoggingInterceptor();
interceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
OkHttpClient client = new OkHttpClient.Builder()
.addInterceptor(interceptor)
.readTimeout(10, TimeUnit.SECONDS)
.connectTimeout(10 / 2, TimeUnit.SECONDS)
.sslSocketFactory(sslSocketFactory().getSocketFactory())
.build();
Gson gson = new GsonBuilder()
.setLenient()
.create();
Retrofit retrofit = new Retrofit.Builder()
.baseUrl(url)
.client(client)
.addConverterFactory(GsonConverterFactory.create(gson))
.build();
API api = retrofit.create(***.class);
Call<ResponseBody> req = api.callGeofencingTrigger(***);
req.enqueue(new Callback<ResponseBody>() {
@Override
public void onResponse(Call<ResponseBody> call, retrofit2.Response<ResponseBody> response) {
try {
String string = response.body().string();
Log.d (TAG, "onResponse() :: success");
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public void onFailure(Call<ResponseBody> call, Throwable t) {
t.printStackTrace();
Log.d (TAG, "onFailure() :: t : "t.getMessage());
}
});
}
}
它再次调用相同的。当应用程序处于后台或前台（进入/停留/离开）时，或者即使用户从最近的任务中杀死应用程序时，它工作正常并给出适当的触发通知。它还正在安排适当的工作。并打电话HTTP请求，当应用程序位于前台时，它工作正常，并且在日志上打印成功。
onResponse() :: success
但是，当应用程序从最近的任务中终止并且设备收到任何地理围栏触发器（进入/停留/离开）时，应用程序会安排作业并调用HTTP请求未正确执行。它给 ：
onFailure() :: t :
</br>java.net.UnknownHostException: Unable to resolve host
"host_name": No address associated with hostname
因此，根据 @Xavier 和 @Stevensen 的回答，如果我的应用程序因最近的任务而终止，则它不会唤醒网络。我尝试过firbase-JobSchedule但仍然面临同样的上述错误。应用是否需要特殊permission打电话HTTP当应用程序从最近的任务中杀死时请求？或者是FCM是更好的选择。但仍然有同样的问题是否FCM即使应用程序因最近的任务而被杀死也会工作吗？做FCM会唤醒网络从客户端向服务器发送消息吗？
