如何在特定日期和特定时间设置通知？

Question

我想做一个通知，在特定的时间出现在特定的日期，正如我在标题中写的那样。现在我的警报在按下按钮后 10 秒内出现。如果我需要设置一个特定的日期，我是否也需要这样做？我需要将日期转换为毫秒并提供此参数？这是我的代码：

package com.example.timeman;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import androidx.core.app.NotificationCompat;
import androidx.core.app.NotificationManagerCompat;
public class ReminderBroadcast extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
    NotificationCompat.Builder builder = new NotificationCompat.Builder(context, "notify")
            .setSmallIcon(R.drawable.ic_baseline_close_24)
            .setContentTitle("Salamabuliy")
            .setContentText("TextNotif")
            .setPriority(NotificationCompat.PRIORITY_DEFAULT)
            ;
    NotificationManagerCompat notificationManager = NotificationManagerCompat.from(context);

    notificationManager.notify(200, builder.build());
}

}

和 OnClick 方法：

public void onClick(View view) {
            Intent intent = new Intent(getActivity(), ReminderBroadcast.class);
            PendingIntent pendingIntent = PendingIntent.getBroadcast(getActivity(), 0, intent, 0);

            AlarmManager alarmManager = (AlarmManager) getActivity().getSystemService(Context.ALARM_SERVICE);

            long timeAtButtonClick = System.currentTimeMillis();

            long tenSecondsInMillis = 1000*10;

            alarmManager.set(AlarmManager.RTC, timeAtButtonClick + tenSecondsInMillis, pendingIntent);
            //displayNotification();
            OpenThis(view);
        }

Answer 1

一个选项是找到从现在到您希望它出现的日期之间的持续时间（以毫秒为单位）。例如;

LocalDateTime now = LocalDateTime.now();

LocalDateTime end = now.plusSeconds(10); // end date can be specific, this is an example

Duration difference = Duration.between(now, end);

long differenceMillis = difference.toMillis();

Answer 2

使用Instant#toEpochMilli() and Instant#plusSeconds如下图：

import java.time.Instant;

import java.time.Instant;

public class Main {
    public static void main(String[] args) {
        Instant now = Instant.now();
        System.out.println(now.toEpochMilli());

        // After 10 seconds
        Instant after10SecFromNow = now.plusSeconds(10);
        long millisAfter10Sec = after10SecFromNow.toEpochMilli();
        System.out.println(millisAfter10Sec);

        // alarmManager.set(AlarmManager.RTC, millisAfter10Sec, pendingIntent);
    }
}

输出：

1597837345043
1597837355043

详细了解 java.time^*、the modern Date-Time API, from Trail: Date Time。

^{* 无论出于何种原因，如果您必须坚持Java 6 或Java 7，您可以使用ThreeTen-Backport which backports most of the java.time functionality to Java 6 & 7. If you are working for an Android project and your Android API level is still not compliant with Java-8, check Java 8+ APIs available through desugaring and 。}

如何在特定日期和特定时间设置通知？

How can I set a notification on a specific day and specific time?

java

notifications

android

push-notification

android-studio