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在AlarmManager中设置每隔一小时周期发送广播,设置后能在adb shell中看到。但一般在经过一个周期之后,再次adb shell中查看,就发现alarmmanager中已经没有装订好的广播了。难道是被os自行取消了?我的手机os是miui7 5.10.8开发版 android 5.1。
装订后,在adb shell看到的形式一般如下,
RTC #2: Alarm{3a928873 type 1 when 1446138667081 com.example.weathertrack}
tag=*alarm*:com.example.weather.WAKEUP
operation=PendingIntent{b5186f4: PendingIntentRecord{3d8cfe1d com.example.weathertrack broadcastIntent}}
u0a233:com.example.weathertrack +1s109ms running, 0 wakeups:
+1s109ms 0 wakes 2 alarms: *alarm*:com.example.weather.WAKEUP
设置alarmmanager的代码如下,
public static void sendBroadcast(Context context) {
AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
long setTime = 1000 * 3600;
Intent intent = new Intent(context, WakeUpApp.class);
intent.addFlags(Intent.FLAG_INCLUDE_STOPPED_PACKAGES);
intent.setAction("com.example.weather.WAKEUP");
PendingIntent pendingIntent = PendingIntent
.getBroadcast(context, 1562, intent, PendingIntent.FLAG_UPDATE_CURRENT);
manager.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + 1000 * 60, setTime, pendingIntent);
}
在AndroidManifest中receiver的定义如下,
<receiver android:name=".receiver.WakeUpApp">
<intent-filter>
<action android:name="com.example.weather.WAKEUP"/>
</intent-filter>
</receiver>
ADD 1:
我在开发者选项中设置了不锁定屏幕,这样在充电中手机就不会休眠。从中午开始到现在,可以发现AlarmManager运行良好,并没有出现定时广播消失的情况…………看来只能明早起来再看,手机在休眠状态下,定时广播是不是会消失。另外,我已经严重怀疑这是miui的锅,在这过程中我大概找到了另一个让人莫名其妙的bug的出现原因。
ADD2
上午再次在adb shell中查看,定时广播果然没了……看来只要待机时间一长,定时广播就会被取消,实在让人费解。
ADD3
让人帮忙在别的手机上试下,定时更新数据正常,看来这是miui的坑了。
另外还有一个坑。在我app中,本来是想定时发送广播唤起后台服务,然后下载数据。我发现即使AlarmManager正常工作,唤醒后台服务之后,下载必然会报错,
10-30 13:46:37.929 26642-26673/com.example.weathertrack W/System.err: java.net.ConnectException: failed to connect to api.thinkpage.cn/115.29.232.24 (port 443) after 10000ms: isConnected failed: ECONNREFUSED (Connection refused)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at libcore.io.IoBridge.isConnected(IoBridge.java:238)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at libcore.io.IoBridge.connectErrno(IoBridge.java:171)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at libcore.io.IoBridge.connect(IoBridge.java:122)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:183)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:456)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at java.net.Socket.connect(Socket.java:882)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.internal.Platform$Android.connectSocket(Platform.java:190)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.Connection.connectSocket(Connection.java:196)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.Connection.connect(Connection.java:172)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.Connection.connectAndSetOwner(Connection.java:367)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.OkHttpClient$1.connectAndSetOwner(OkHttpClient.java:128)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:328)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:245)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.Call.getResponse(Call.java:267)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.Call$ApplicationInterceptorChain.proceed(Call.java:224)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.Call.getResponseWithInterceptorChain(Call.java:195)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.Call.access$100(Call.java:34)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.Call$AsyncCall.execute(Call.java:162)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at com.squareup.okhttp.internal.NamedRunnable.run(NamedRunnable.java:33)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at java.lang.Thread.run(Thread.java:818)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: Caused by: android.system.ErrnoException: isConnected failed: ECONNREFUSED (Connection refused)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: at libcore.io.IoBridge.isConnected(IoBridge.java:223)
10-30 13:46:37.939 26642-26673/com.example.weathertrack W/System.err: ... 21 more
看日志第一行,我查过之后发现这个错误一般是因为服务器端出错造成的。但是在我这个例子中肯定不是网站服务器的问题,每次只要我在打开app的情况下手动更新数据,就能正常下载数据。另外,今天下午别人的测试反馈也是软件定时更新数据正常。
我在adb shell中查看了logcat,发现只要开始网络连接,小米内置的网络助手就会监控,
10-30 13:46:37.929 I/XiaomiFirewall(10262): firewall pkgName:com.example.weathertrack, result:0
但是无法确认是不是小米网络助手的问题,因为即使正常连接,也会返回如上日志。
伊谢尔伦2017-04-17 14:45:16
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