Question

我正在尝试在特定日期显示通知，我正在使用警报管理器和广播接收器来显示通知，但问题是通知仅在应用程序打开且应用程序关闭时才起作用。下面是我的代码：

Reminder.java

public class Reminder extends AppCompatActivity {

long reminderDateTimeInMilliseconds = 000;
Button but;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_reminder);

    but = findViewById(R.id.but);

    but.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            createNotifyChannel();

            Intent intent = new Intent(Reminder.this,ReminderBroadcast.class);
            PendingIntent pendingIntent = PendingIntent.getBroadcast(Reminder.this,0,intent,0);


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

            Calendar calendarToSchedule = Calendar.getInstance();
            calendarToSchedule.setTimeInMillis(System.currentTimeMillis());
            calendarToSchedule.clear();

            //.Set(Year, Month, Day, Hour, Minutes, Seconds);
            calendarToSchedule.set(2020, 8, 20, 19, 12, 0);
            reminderDateTimeInMilliseconds = calendarToSchedule.getTimeInMillis();

            alarmManager.setExact(AlarmManager.RTC_WAKEUP,reminderDateTimeInMilliseconds,pendingIntent);

        }
    });
}

private void createNotifyChannel(){

      if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O){

          CharSequence name = "ReminChannel";
          String desc = "This is my channel";
          int importance = NotificationManager.IMPORTANCE_DEFAULT;
          NotificationChannel channel = new NotificationChannel("mynotif",name,importance);
          channel.setDescription(desc);

          NotificationManager notificationManager = getSystemService(NotificationManager.class);
          notificationManager.createNotificationChannel(channel);
      }
   }
}

ReminderBroadcast.java

public class ReminderBroadcast extends BroadcastReceiver {

@Override
public void onReceive(Context context, Intent intent) {

NotificationCompat.Builder notif = new NotificationCompat.Builder(context,"mynotif")
                                   .setContentTitle("Appointment reminder")
                                   .setContentText("Hello there")
                                   .setPriority(NotificationCompat.PRIORITY_DEFAULT);

NotificationManagerCompat manager = NotificationManagerCompat.from(context);
manager.notify(200,notif.build());

  }
}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.app.firstapp">

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".Reminder">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />

        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>
<activity android:name=".ThirdActivity" />
<activity android:name=".SecondActivity" />
<activity android:name=".MainActivity">

</activity>

<receiver android:name=".ReminderBroadcast"/>

</application>

</manifest>

请让我知道我做错了什么，我们将不胜感激。

谢谢

应用关闭时无法显示通知

0 个答案: