我正在寻找一种在preference中创建Settings的方法，以便在一天中的特定时间（由用户在设置中设置）在Android应用中发送通知。我看过像this这样的不同线程，但这在Android Oreo中不起作用。
有人可以帮我解决这个问题或为我提供教程吗？
答案 0 :(得分：6)
在查看了不同的帖子以及对AlarmManager的实现进行了一些研究之后，这才对我有用。
此操作的基础是this发布和安排Android Documentation重复警报。
这是我当前的实现方式：
我有一个SwitchPreference，一个TimePicker实现是Settings
SwitchPreference，询问用户是否要启用“重复每日通知”。
TimePicker设置通知时间。
在MainActivity的{{1}}方法中或您在阅读OnCreate的任何地方，请执行以下操作：
SharedPreferences接下来添加实现PreferenceManager.setDefaultValues(this, R.xml.preferences, false);
SharedPreferences sharedPref = PreferenceManager.getDefaultSharedPreferences(this);
Boolean dailyNotify = sharedPref.getBoolean(SettingsActivity.KEY_PREF_DAILY_NOTIFICATION, true);
PackageManager pm = this.getPackageManager();
ComponentName receiver = new ComponentName(this, DeviceBootReceiver.class);
Intent alarmIntent = new Intent(this, AlarmReceiver.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, alarmIntent, 0);
AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
// if user enabled daily notifications
if (dailyNotify) {
//region Enable Daily Notifications
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.set(Calendar.HOUR_OF_DAY, sharedPref.getInt("dailyNotificationHour", 7));
calendar.set(Calendar.MINUTE, sharedPref.getInt("dailyNotificationMin", 15));
calendar.set(Calendar.SECOND, 1);
// if notification time is before selected time, send notification the next day
if (calendar.before(Calendar.getInstance())) {
calendar.add(Calendar.DATE, 1);
}
if (manager != null) {
manager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),
AlarmManager.INTERVAL_DAY, pendingIntent);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
manager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent);
}
}
//To enable Boot Receiver class
pm.setComponentEnabledSetting(receiver,
PackageManager.COMPONENT_ENABLED_STATE_ENABLED,
PackageManager.DONT_KILL_APP);
//endregion
} else { //Disable Daily Notifications
if (PendingIntent.getBroadcast(this, 0, alarmIntent, 0) != null && manager != null) {
manager.cancel(pendingIntent);
//Toast.makeText(this,"Notifications were disabled",Toast.LENGTH_SHORT).show();
}
pm.setComponentEnabledSetting(receiver,
PackageManager.COMPONENT_ENABLED_STATE_DISABLED,
PackageManager.DONT_KILL_APP);
}
的{{1}}类，
AlarmReceiver如果设备断电或重启，系统将关闭BroadcastReceiver，因此请在public class AlarmReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(Objects.requireNonNull(context));
SharedPreferences.Editor sharedPrefEditor = prefs.edit();
NotificationManager nm = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
Intent notificationIntent = new Intent(context, MainActivity.class);
notificationIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP
| Intent.FLAG_ACTIVITY_SINGLE_TOP);
PendingIntent pendingI = PendingIntent.getActivity(context, 0,
notificationIntent, 0);
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
NotificationChannel channel = new NotificationChannel("default",
"Daily Notification",
NotificationManager.IMPORTANCE_DEFAULT);
channel.setDescription("Daily Notification");
if (nm != null) {
nm.createNotificationChannel(channel);
}
}
NotificationCompat.Builder b = new NotificationCompat.Builder(context, "default");
b.setAutoCancel(true)
.setDefaults(NotificationCompat.DEFAULT_ALL)
.setWhen(System.currentTimeMillis())
.setSmallIcon(R.mipmap.ic_launcher_foreground)
.setTicker("{Time to watch some cool stuff!}")
.setContentTitle("My Cool App")
.setContentText("Time to watch some cool stuff!")
.setContentInfo("INFO")
.setContentIntent(pendingI);
if (nm != null) {
nm.notify(1, b.build());
Calendar nextNotifyTime = Calendar.getInstance();
nextNotifyTime.add(Calendar.DATE, 1);
sharedPrefEditor.putLong("nextNotifyTime", nextNotifyTime.getTimeInMillis());
sharedPrefEditor.apply();
}
}
}
上重新启动它，添加以下类：
AlarmManager最后，不要忘记将这些权限添加到BOOT COMPLETE：
public class DeviceBootReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
if (Objects.equals(intent.getAction(), "android.intent.action.BOOT_COMPLETED")) {
// on device boot complete, reset the alarm
Intent alarmIntent = new Intent(context, AlarmReceiver.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0, alarmIntent, 0);
AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
final SharedPreferences sharedPref = PreferenceManager.getDefaultSharedPreferences(Objects.requireNonNull(context));
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.set(Calendar.HOUR_OF_DAY, sharedPref.getInt("dailyNotificationHour", 7));
calendar.set(Calendar.MINUTE, sharedPref.getInt("dailyNotificationMin", 15));
calendar.set(Calendar.SECOND, 1);
Calendar newC = new GregorianCalendar();
newC.setTimeInMillis(sharedPref.getLong("nextNotifyTime", Calendar.getInstance().getTimeInMillis()));
if (calendar.after(newC)) {
calendar.add(Calendar.HOUR, 1);
}
if (manager != null) {
manager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),
AlarmManager.INTERVAL_DAY, pendingIntent);
}
}
}
}
并在AndroidManidest
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
AndroidManifest应该在<application
<!--YOUR APPLICATION STUFF-->
<receiver android:name=".DeviceBootReceiver"
android:enabled="false">
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED" />
</intent-filter>
</receiver>
<receiver android:name=".AlarmReceiver" />
指定的一天的特定时间设置，并且如果用户启用了Notification。
答案 1 :(得分：2)
关于如何在StackOverflow上执行此操作的示例很多，但是不幸的是，由于Google更改了AlarmManager的工作方式，这些示例都不再起作用。
允许开发人员在特定时间唤醒设备的 only AlarmManager选项是AlarmManager.setAlarmClock。
除了警报之外，您还可以设置一个意图，使您可以在单击警报时启动应用程序。
还可以使用高优先级FCM Firebase Cloud Message在特定时间唤醒设备。
但是总而言之，没有其他选择：'setExact'和关联的方法不再像广告名称一样起作用。