Android AlarmManager 无法正常工作

Question

我在我的应用程序上使用警报管理器，我需要在 2:00 AM 重置一些 DefaultSharedPreferences 值（设置为 0）。我的主 activity 上有一个函数，只要打开应用程序就会调用该函数：

protected void setUpAlarmManager(){ //To delete the data of each day and pass it to Records database
        AlarmManager alarmManager = (AlarmManager) this.getSystemService(Context.ALARM_SERVICE);
        Intent intent  = new Intent(this, AlarmReceiver.class);
        PendingIntent pIntent = PendingIntent.getBroadcast(this, 1, intent,  PendingIntent.FLAG_CANCEL_CURRENT);
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.HOUR_OF_DAY, 02);
        calendar.set(Calendar.MINUTE, 00);
        calendar.set(Calendar.SECOND, 00);
        alarmManager.setInexactRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), AlarmManager.INTERVAL_DAY , pIntent); //set repeating every 24 hours
        Log.i("Set", "Alarm set");
    }

然后我使用 BroadcastReceiver 重置值。

package com.javierd.iifym;

import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.util.Log;

import com.javierd.iifym.sqlite.RecordsDataSource;

//To delete the data of each day and pass it to Records database
public class AlarmReceiver extends android.content.BroadcastReceiver {

    private RecordsDataSource dataSource;
    private Utils utils;

    @Override
    public void onReceive(Context context, Intent intent) {
        Log.i("Time", "TIMEEEE!!!!");
        SharedPreferences macros = context.getSharedPreferences(context.getPackageName() + "_preferences", Context.MODE_PRIVATE); //As we store data using DefaultSharedPreferences, not SharedPreferences
        SharedPreferences.Editor editor = macros.edit();
        editor.putString("eaten_carbs", "0");
        editor.putString("eaten_proteins", "0");
        editor.putString("eaten_fats", "0");
        editor.apply();
    }
}

接收器正常工作，问题是 AlarmManager 随机工作。虽然它应该是在 2:00 上午，也许你在 16:00 进入应用程序，保存一些值，在下次你在 17:30 进入时，这些值被删除，或者可能没有，这是随机的，我不明白。

Answer 1

这样的效果我相信是使用AlarmManager.setInexectRepeating(int, long, long, PendingIntent)造成的。根据documentation

Your alarm's first trigger will not be before the requested time, but it might not occur for almost a full interval after that time.

当您使用此方法时，Android 同步多个不精确重复的警报并同时触发它们。考虑到间隔是一天，警报可能会在 17:30.

触发

如果闹钟需要在上午 2:00 准时触发，那么我建议改用 AlarmManager.setRepeating(int, long, long, PendingIntent) 方法。

请注意，建议尽可能避免使用精确警报，以减少电池电量消耗。

已更新。

我建议检查触发时间是否在过去。

你能试试吗

protected void setUpAlarmManager(){ //To delete the data of each day and pass it to Records database
        AlarmManager alarmManager = (AlarmManager) this.getSystemService(Context.ALARM_SERVICE);
        Intent intent  = new Intent(this, AlarmReceiver.class);
        PendingIntent pIntent = PendingIntent.getBroadcast(this, 1, intent,  PendingIntent.FLAG_CANCEL_CURRENT);
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.HOUR_OF_DAY, 2);
        calendar.set(Calendar.MINUTE, 0);
        calendar.set(Calendar.SECOND, 0);
        if (Calendar.getInstance().after(calendar)) {
             calendar.add(Calendar.DAY_OF_MONTH, 1);
        }
        alarmManager.setInexactRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), AlarmManager.INTERVAL_DAY , pIntent); //set repeating every 24 hours
        Log.i("Set", "Alarm set");
    }

Android AlarmManager 无法正常工作

Android AlarmManager doesn´t work properly

android

alarmmanager

android-broadcastreceiver