无法通过无线网络从后台服务来访问互联网 [英] Unable to access Internet via WiFi from a Background service
问题描述
我会直接到一些事实/数字我发现请帮助我,如果你面对/解决类似的问题。
I'll get straight onto some facts/figures I discovered pls help me if you've faced/solved a similar problem.
我发回的数据每5分钟到一个服务器,除非用户手动切换它关闭了清醒广播接收器
通过意图帮助服务
。另外,我得到的wifi锁在做之前,(我试过这个已经没有锁;不工作要么)
I send back data every 5 minutes to a server unless the user manually toggles it Off with the help of a wakeful broadcast receiver
through a intent service
. Plus I get wifi locks before doing (I've tried this already without locks; doesnt work either)
现在的设备发回的常规数据的网络数据(2G / 3G / 4G)能正常工作,但对那些连接到WiFi网络莫名其妙地让我一个 getActiveNetworkInfo()
为空
(甚至直接打到网站的URL给出了一个主机名未找到错误
)这确实发生在的HTC One(与v.4.4.2安装)其他设备做做工精细。
Now on devices sending back data from regular data networks (2G/3G/4G) this works fine but on those connected to a wifi network somehow gets me a getActiveNetworkInfo()
as null
(Even directly hitting the web URL gives a hostname not found error
) this surely happens on HTC One (with v.4.4.2 installed) others devices do work fine.
-
我们都知道了previous官方的连接管理器已经在返回即使网络不/提供太多的真/假条件有问题。我很怀疑他们是否已经出现反复,或者只是一些自定义的OEM京爆炸
we all know about the previous official connectivity manager have had issues in returning too much true / false condition even if network was not/available. I highly doubt if they've cropped up again or is just some custom OEM jing-bang
报警被炒鱿鱼>>激发了清醒广播接收器GT;>得到的wifi锁>>睡眠线程内3秒的
onReceive`获得锁,以等待的WiFi恢复连接>>后做了以后我的服务工作。
the alarm gets fired >> fires up the wakeful broadcast receiver >> get wifi locks >> sleep the thread for 3 secs inside the
onReceive` after getting locks in order to wait for wifi to resume connectivity >> do my service work afterwards.
我体重强制使用移动数据连接,而不是无线的可能性。 (通过使用 startUsingNetworkFeature()
)有没有人有相同的解决方案?
am weighing the possibility of forcing use of mobile data connection instead of wifi. (by using startUsingNetworkFeature()
) Does anyone have a solution for the same?
推荐答案
希望我不是太晚了,我有一个问题,就像你的。我的应用程序发送数据(从内部存储文件)服务器在一定的时间间隔(30米/ 1H / 2H / 4H)需要。对于 getActiveNetworkInfo()
给予正确的结果,你需要唤醒的WiFi(因为此前的手机wifi的睡眠5-15分钟关闭)。这给了我很大的麻烦,但这里的如何我的解决方案如下:
Hope I'm not too late, I had a problem just like yours. My app needed to send data (from internal storage file) to server at certain intervals (30m/1h/2h/4h). For getActiveNetworkInfo()
to give proper result, you need to wake the wifi (because after 5-15 min of phone sleep wifi turns off). That gave me a lot of trouble, but here's how my solution works:
首先,我有一个 WakefulBroadcastReceiver
被调用,当我需要唤醒电话:
First, I have a WakefulBroadcastReceiver
that gets called when I need to wake the phone:
/** Receiver for keeping the device awake */
public class WakeUpReceiver extends WakefulBroadcastReceiver {
// Constant to distinguish request
public static final int WAKE_TYPE_UPLOAD = 2;
// AlarmManager to provide access to the system alarm services.
private static AlarmManager alarm;
// Pending intent that is triggered when the alarm fires.
private static PendingIntent pIntent;
/** BroadcastReceiver onReceive() method */
@Override
public void onReceive(Context context, Intent intent) {
// Start appropriate service type
int wakeType = intent.getExtras().getInt("wakeType");
switch (wakeType) {
case WAKE_TYPE_UPLOAD:
Intent newUpload = new Intent(context, UploadService.class);
startWakefulService(context, newUpload);
break;
default:
break;
}
}
/** Sets alarms */
@SuppressLint("NewApi")
public static void setAlarm(Context context, int wakeType, Calendar startTime) {
// Set alarm to start at given time
alarm = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(context, WakeUpReceiver.class);
intent.putExtra("wakeType", wakeType);
pIntent = PendingIntent.getBroadcast(context, wakeType, intent,
PendingIntent.FLAG_UPDATE_CURRENT);
// For android 4.4+ the method is different
if (android.os.Build.VERSION.SDK_INT >=
android.os.Build.VERSION_CODES.KITKAT) {
alarm.setExact(AlarmManager.RTC_WAKEUP,
startTime.getTimeInMillis() + 5000, pIntent);
} else {
alarm.set(AlarmManager.RTC_WAKEUP,
startTime.getTimeInMillis() + 5000, pIntent);
}
// The + 5000 is for adding symbolic 5 seconds to alarm start
}
}
注意公共静态无效setAlarm(背景下,INT,日历)
功能,我使用该功能来设置报警(见主要应用)。
Note the public static void setAlarm(Context, int, Calendar)
function, I use that function to set the alarms (see Main application).
接下来,服务本身并不是一个 IntentService
,只是服务
:
Next, the service itself isn't an IntentService
, just Service
:
/** Service for uploading data to server */
public class UploadService extends Service {
private static final String serverURI = "http://your.server.com/file_on_server.php";
private Looper mServiceLooper;
private ServiceHandler mServiceHandler;
WifiLock wfl;
private Intent currentIntent;
private SharedPreferences sharedPrefs;
private int updateInterval;
private boolean continueService;
/** Service onCreate() method */
@Override
public void onCreate() {
super.onCreate();
// Initialize wifi lock
wfl = null;
// Initialize current Intent
currentIntent = null;
// Create separate HandlerThread
HandlerThread thread = new HandlerThread("SystemService",
Process.THREAD_PRIORITY_BACKGROUND);
thread.start();
// Get the HandlerThread's Looper and use it for our Handler
mServiceLooper = thread.getLooper();
mServiceHandler = new ServiceHandler(mServiceLooper);
// Get shared variables values if set
sharedPrefs = getSharedPreferences("serviceVars", MODE_PRIVATE);
updateInterval = sharedPrefs.getInt("sendInterval", 60); // in your case 5
continueService = sharedPrefs.getBoolean("bgServiceState", false);
}
/** Service onStartCommand() method */
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// If continuing, set new alarm
if (continueService) {
Calendar nextStart = Calendar.getInstance();
nextStart.set(Calendar.SECOND, 0);
// Set alarm to fire after the interval time
nextStart.add(Calendar.MINUTE, updateInterval);
WakeUpReceiver.setAlarm(this, WakeUpReceiver.WAKE_TYPE_UPLOAD,
nextStart);
}
// Get current Intent and save it
currentIntent = intent;
// Acquire a wifi lock to ensure the upload process works
WifiManager wm = (WifiManager) getSystemService(Context.WIFI_SERVICE);
wfl = wm.createWifiLock(WifiManager.WIFI_MODE_FULL, "WifiLock");
if (!wfl.isHeld()) {
wfl.acquire();
}
// For each start request, send a message to start a job and give
// start ID so we know which request we're stopping when we finish
Message msg = mServiceHandler.obtainMessage();
msg.arg1 = startId;
mServiceHandler.sendMessage(msg);
// If service gets killed, it will restart
return START_STICKY;
}
/** Handler that receives messages from the thread */
private final class ServiceHandler extends Handler {
public ServiceHandler(Looper looper) {
super(looper);
}
/** Executes all service operations */
@Override
public void handleMessage(Message msg) {
// First wait for 5 seconds
synchronized (this) {
try {
wait(5 * 1000);
} catch (Exception e) {
e.printStackTrace();
}
}
// Start checking if internet is enabled
boolean hasInternet = false;
long endTime = System.currentTimeMillis() + 55 * 1000;
// Check every second (max 55) if connected
while (System.currentTimeMillis() < endTime) {
if (hasInternet(UploadService.this)) {
hasInternet = true;
break;
}
synchronized (this) {
try {
wait(1000);
} catch (Exception e) {
e.printStackTrace();
}
}
}
// Connected to internet or 60 (5 + 55) seconds passed
if (hasInternet) {
// Connect to server
connectToServer(serverURI, fileName);
} else {
// Can't connect, send message or something
}
// Stop service
stopSelf(msg.arg1);
}
}
/** Checks if phone is connected to Internet */
private boolean hasInternet(Context context) {
ConnectivityManager cm = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo ni = null;
if (cm != null) {
ni = cm.getActiveNetworkInfo();
}
return ni != null && ni.getState() == NetworkInfo.State.CONNECTED;
}
/** Service onDestroy() method */
@Override
public void onDestroy() {
// Release wifi lock
if (wfl != null) {
if (wfl.isHeld()) {
wfl.release();
}
}
// Release wake lock provided by BroadcastReceiver.
WakeUpReceiver.completeWakefulIntent(currentIntent);
super.onDestroy();
}
/** Performs server communication */
private void connectToServer(String serverUri, String dataFileName) {
// this function does my network stuff
}
/** Service onBind() method - Not used */
@Override
public IBinder onBind(Intent intent) {
return null;
}
}
我也有一个启动
的BroadcastReceiver
,因此,如果闹钟设置,然后手机重新启动,就可以运行服务再次:
I also have a BOOT
BroadcastReceiver
, so if alarm is set and then phone is rebooted it will run service again:
/** Receiver for (re)starting alarms on device reboot operations */
public class BootReceiver extends BroadcastReceiver {
WakeUpReceiver alarm = new WakeUpReceiver();
/** BroadcastReceiver onReceive() method */
@Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals("android.intent.action.BOOT_COMPLETED")) {
WakeUpReceiver.setAlarm(context, WakeUpReceiver.WAKE_TYPE_UPLOAD,
Calendar.getInstance());
}
}
}
最后,但并非最不重要的主活动
,我通过启动接收器启动该服务:
Last, but not least in the Main Activity
, I start the service by starting receivers:
// Start upload service now
Calendar timeNow = Calendar.getInstance();
WakeUpReceiver.setAlarm(this, WakeUpReceiver.WAKE_TYPE_UPLOAD, timeNow);
// Enable BootReceiver to (re)start alarm on device restart
getPackageManager().setComponentEnabledSetting(
new ComponentName(this, BootReceiver.class),
PackageManager.COMPONENT_ENABLED_STATE_ENABLED,
PackageManager.DONT_KILL_APP);
当我停止服务,我停止启动
接收器也:
// Disable BootReceiver to (re)start alarm on device restart
getPackageManager().setComponentEnabledSetting(
new ComponentName(this, BootReceiver.class),
PackageManager.COMPONENT_ENABLED_STATE_DISABLED,
PackageManager.DONT_KILL_APP);
此外,不要忘了添加适当的权限和组件来体现:
Additionally, don't forget to add proper permissions and components to manifest:
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<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_WIFI_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<receiver
android:name=".BootReceiver"
android:enabled="false" >
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED" />
</intent-filter>
</receiver>
<receiver android:name=".WakeUpReceiver" />
<service
android:name=".UploadService"
android:enabled="true"
android:label="ServerUpload"
android:launchMode="singleInstance" />
我想我介绍这一切,我会很高兴,如果这有助于任何人解决他们的问题。
I think I covered it all, I'll be glad if this helps anyone solve their problems.
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