8

我遇到了 AlarmManager 的问题。

简而言之，我计划了一个 alarmManager ：

Intent intent = new Intent(context, MyActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);
AlarmManager alarmManager = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
alarmManager.setExact(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime() + delayInMs, pendingIntent);

并且活动 MyActivity 在指定时间出现。就在设备插入时。当它放在我的口袋里或延迟几分钟时，它也可以工作。但是当我在晚上之前设置 alarmManager 时，它不会在早上工作。但是，只要我拿起手机或解锁屏幕，它就会起作用。

所以，我想这是由于设备的睡眠模式，但如何解决呢？

1）我在myActivity的每个方法中都添加了一个日志，我确信在我手动唤醒设备之前没有人被调用。2）我尝试了 PowerManagement 的唤醒锁（在清单中使用 WAKE_LOCK 权限），但没有任何改变：

alarmManager.setExact(.........);
wakeLock = ((PowerManager)contexte.getSystemService(Context.POWER_SERVICE)).newWakeLock(PowerManager.PROXIMITY_SCREEN_OFF_WAKE_LOCK, "MyActivity");
wakeLock.acquire();

请帮忙 ！我确定我已经很接近了...

编辑 2016 年 12 月 4 日：感谢 Nick Friskel 和 Vikram Rao，我将初始代码更改为调用广播接收器并在 onReceive 中获取我的唤醒锁。不幸的是，它似乎不起作用。当手机插上电源或计划在 35 分钟后发出警报时，它可以完美运行，但是对于整个晚上，onReceive 甚至都没有被调用。那天晚上我尝试了，计划在上午 9:00 发出警报，但 onReceive 仅在上午 9:46 执行，这意味着我解锁设备的那一刻。这是我的新代码：

Intent intent = new Intent("com.blah.something.ALARM_RECEIVED");
PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_ONE_SHOT);
AlarmManager alarmManager = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
alarmManager.cancel(pendingIntent);
alarmManager.setExact(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime() + delayInMs, pendingIntent);

也就是说，出于某种原因，我的日志写“onReceive 的开始”并不是真正在侦听器的开头。我只是设法把它放在真正的开头，所以我会看看是否调用了监听器。

编辑 2016 年 12 月 5 日：所以，我在 onReceive 的顶部更改了日志写入，并且发生了同样的问题：一旦我手动唤醒设备，就会调用 onReceive 的开始。我可以实现wakefulBroadcastReceiver，但我担心它不会解决任何问题。如果我理解正确，wakefulBroadcastReceiver 有助于防止设备在 onReceive 和活动或服务启动之间休眠。但是如果 onReceive 甚至没有被调用呢？我有点绝望……也许我应该直接问索尼。此外，我的手机有耐力模式，但它没有被激活。

编辑 2016 年 12 月 11 日： 所以，通过更多测试，我现在确定我什么都不懂......我设置了一个每 5 分钟激活一次的广播接收器（onReceive 会在 5 分钟后重置警报管理器），我可以看到它是完美的工作......有时。它可以持续几个小时，然后睡两个小时，然后可以睡30分钟，然后再睡。（当我的手机打开、拔掉电源并闲置时，所有这些）。我将删除所有代码，但我们感兴趣的是什么。这将更容易理解，我将能够在这里编写所有活动代码。

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.par.hasard.mysimpleapplication">
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <receiver android:name="com.par.hasard.mysimpleapplication.MySimpleReceiver">
            <intent-filter android:priority="1">
                <action android:name="com.par.hasard.mysimpleapplication.REGULAR_ALARM" />
            </intent-filter>
        </receiver>
    </application>
</manifest>

MainActivity.java

package com.par.hasard.mysimpleapplication;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button button = (Button)findViewById(R.id.myExportButton);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                MyLogManager.copyLogToClipboard(view.getContext());
                MyLogManager.emptyLogFile(view.getContext());
            }
        });
        try {
            MyLogManager.createLogFile(this);
            MyLogManager.write(this, "Application launched\n");
            MyAlarmPlanner.planAlarm(this);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

MySimpleReceiver.java

package com.par.hasard.mysimpleapplication;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;

public class MySimpleReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        try {
            MyLogManager.write(context, "Beginning of onReceive\n");
            MyAlarmPlanner.planAlarm(context);
            MyLogManager.write(context, "End of onReceive\n");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

MyAlarmPlanner.java

package com.par.hasard.mysimpleapplication;

import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.os.SystemClock;
import java.io.IOException;

public class MyAlarmPlanner {
    public static void planAlarm(Context context) throws IOException {
        MyLogManager.write(context, "Beginning of alarm planning\n");
        AlarmManager alarmManager = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
        Intent intent = new Intent("com.par.hasard.mysimpleapplication.REGULAR_ALARM");
        PendingIntent pendingIntent =  PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_CANCEL_CURRENT);
        alarmManager.cancel(pendingIntent);
        alarmManager.setExact(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime() + 300000, pendingIntent);
        MyLogManager.write(context, "End of alarm planning\n");
    }
}

我不认为 MyLogManager.java 有用，它只是无聊的文件管理方法。

长时间空闲后的日志文件内容：

12/12 15h33m23s380 => Beginning of onReceive
12/12 15h33m23s381 => Beginning of alarm planning
12/12 15h33m23s383 => End of alarm planning
12/12 15h33m23s384 => End of onReceive
12/12 15h38m24s337 => Beginning of onReceive
12/12 15h38m24s339 => Beginning of alarm planning
12/12 15h38m24s375 => End of alarm planning
12/12 15h38m24s376 => End of onReceive
12/12 15h43m24s375 => Beginning of onReceive
12/12 15h43m24s376 => Beginning of alarm planning
12/12 15h43m24s380 => End of alarm planning
12/12 15h43m24s381 => End of onReceive
12/12 15h48m25s301 => Beginning of onReceive
12/12 15h48m25s304 => Beginning of alarm planning
12/12 15h48m25s307 => End of alarm planning
12/12 15h48m25s308 => End of onReceive
12/12 15h53m25s316 => Beginning of onReceive
12/12 15h53m25s318 => Beginning of alarm planning
12/12 15h53m25s328 => End of alarm planning
12/12 15h53m25s329 => End of onReceive
12/12 15h58m25s328 => Beginning of onReceive
12/12 15h58m25s329 => Beginning of alarm planning
12/12 15h58m25s331 => End of alarm planning
12/12 15h58m25s333 => End of onReceive
12/12 16h3m26s336 => Beginning of onReceive
12/12 16h3m26s351 => Beginning of alarm planning
12/12 16h3m26s379 => End of alarm planning
12/12 16h3m26s380 => End of onReceive
12/12 16h8m26s397 => Beginning of onReceive
12/12 16h8m26s401 => Beginning of alarm planning
12/12 16h8m26s404 => End of alarm planning
12/12 16h8m26s405 => End of onReceive
12/12 16h13m26s406 => Beginning of onReceive
12/12 16h13m26s407 => Beginning of alarm planning
12/12 16h13m26s410 => End of alarm planning
12/12 16h13m26s411 => End of onReceive
12/12 16h18m27s328 => Beginning of onReceive
12/12 16h18m27s329 => Beginning of alarm planning
12/12 16h18m27s346 => End of alarm planning
12/12 16h18m27s348 => End of onReceive
12/12 16h23m28s298 => Beginning of onReceive
12/12 16h23m28s299 => Beginning of alarm planning
12/12 16h23m28s303 => End of alarm planning
12/12 16h23m28s304 => End of onReceive
12/12 16h28m29s308 => Beginning of onReceive
12/12 16h28m29s310 => Beginning of alarm planning
12/12 16h28m29s323 => End of alarm planning
12/12 16h28m29s324 => End of onReceive
12/12 16h33m29s339 => Beginning of onReceive
12/12 16h33m29s340 => Beginning of alarm planning
12/12 16h33m29s355 => End of alarm planning
12/12 16h33m29s361 => End of onReceive
12/12 16h38m29s356 => Beginning of onReceive
12/12 16h38m29s357 => Beginning of alarm planning
12/12 16h38m29s360 => End of alarm planning
12/12 16h38m29s361 => End of onReceive
12/12 16h43m29s364 => Beginning of onReceive
12/12 16h43m29s365 => Beginning of alarm planning
12/12 16h43m29s367 => End of alarm planning
12/12 16h43m29s369 => End of onReceive
12/12 16h48m29s376 => Beginning of onReceive
12/12 16h48m29s380 => Beginning of alarm planning
12/12 16h48m29s390 => End of alarm planning
12/12 16h48m29s394 => End of onReceive
12/12 16h53m29s392 => Beginning of onReceive
12/12 16h53m29s394 => Beginning of alarm planning
12/12 16h53m29s402 => End of alarm planning
12/12 16h53m29s403 => End of onReceive
12/12 17h43m33s986 => Beginning of onReceive      //problem, the 16'58 onReceive wasn't called
12/12 17h43m33s988 => Beginning of alarm planning
12/12 17h43m33s996 => End of alarm planning
12/12 17h43m34s4 => End of onReceive
12/12 17h48m34s535 => Beginning of onReceive
12/12 17h48m34s536 => Beginning of alarm planning
12/12 17h48m34s539 => End of alarm planning
12/12 17h48m34s540 => End of onReceive
12/12 18h29m49s635 => Beginning of onReceive     //the moment I turned on my device
12/12 18h29m49s648 => Beginning of alarm planning
12/12 18h29m49s667 => End of alarm planning
12/12 18h29m49s668 => End of onReceive

有人能告诉我我的错误在哪里吗？

4

3 回答 3

6

感谢CommonsWare，问题解决了！此失败是由于打盹模式（https://developer.android.com/training/monitoring-device-state/doze-standby.html） 简而言之，从 Android 6.0 开始，AlarmManager 受到影响，如果设备处于这种打瞌睡模式。但是您可以将 setExact 替换为 setExactAndAllowWhileIdle。有限制，但我们必须处理。有指向 CommonsWare 回答的帖子的链接： sendWakefulWork 并不总是使用 cwac-wakeful-1.1.0 调用

于 2016-12-25T12:40:34.010 回答
1

android 中的 AlarmManager api 有其局限性。为了 -

  1. 它在设备重启时被清除（所有警报丢失）
  2. 在设备锁定/睡眠状态下，制造商和 android 版本之间的行为不一致

我解决这些问题的方法是-

  1. 创建具有广播意图的警报，然后将侦听器添加到该广播以执行必要的操作。

像这样 -

Intent intent = new Intent("com.blah.something.ALARM_RECIEVED");
PendingIntent pendingIntent =  PendingIntent.getBroadcast(context, requestCode, intent, PendingIntent.FLAG_ONE_SHOT);
AlarmManager alarmManager = (AlarmManager) context.getSystemService(Html5Activity.ALARM_SERVICE);
alarmManager.set(AlarmManager.RTC, triggerTimeInMillis, pendingIntent);

清单文件 -

<receiver android:name=".receiver.BackgroundScheduledAlarmReceiver">
     <intent-filter android:priority="1">
          <action android:name="com.blah.something.ALARM_RECIEVED" />
     </intent-filter>
</receiver>
  1. 将警报保存在 sqlite 或某处（此处未显示），并在设备重启时通过像这样收听设备启动来重新创建它们 -

清单文件 -

<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
...
<receiver
    android:name=".receiver.RecreateAlarmsAtBootReceiver"
    android:enabled="true"
    android:exported="true"
    android:label="RecreateAlarmsAtBootReceiver">
    <intent-filter>
        <action android:name="android.intent.action.BOOT_COMPLETED" />
        <action android:name="android.intent.action.QUICKBOOT_POWERON" />
    </intent-filter>
</receiver>

在RecreateAlarmsAtBootReceiver中，读取存储警报的 sqlite 并再次将它们添加到警报管理器。

于 2016-12-02T03:13:31.990 回答
0

正确的方法是让您的 AlarmManager 触发 BroadcastReceiver 而不是直接的 Activity。然后，您可以将唤醒锁放在广播接收器类中，然后从 BroadcastReceiver 或从 BroadcastReceiver 启动的 IntentService 运行您的活动。

您的意图将更改为：

Intent intent = new Intent(context, MyActivityReceiver.class);

然后制作你的广播接收器：

package com.yourpackage (change this to your package)

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;

public class MyActivityReceiver extends BroadcastReceiver {
    public static final int REQUEST_CODE = 0; //only necessary if you have more receivers 

    // when the alarm is triggered
    @Override
    public void onReceive(Context context, Intent intent) {
    wakeLock = ((PowerManager)contexte.getSystemService(Context.POWER_SERVICE)).newWakeLock(PowerManager.PROXIMITY_SCREEN_OFF_WAKE_LOCK, "MyActivity");
    wakeLock.acquire();
    Intent i = new Intent(context, MyActivity.class);
    context.startService(i);
    }
}

并将接收器添加到您的清单中：

<receiver
            android:name="service.TimeService"
            android:enabled="true"
            android:exported="false"
            >
</receiver>

如果这不起作用，那么您需要通过 WakefulService 开始您的活动。

于 2016-12-02T02:28:12.537 回答