Notification이란?

• 상태바에 앱의 상태를 출력하여 유저에게 알림을 보내는 기능
• 상태바는 시스템에 의해 관리되기 때문에, 액티비티에서 직접 제어가 불가능하다.

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Notification 생성

• NotificationChannel로 NotificationCompat.Builder를 생성하며, 이 빌더로 Notification 객체를 생성한다.
• 알림은 NotificationManager의 notify() 함수로 발생시킨다.
  cf) NotificationCompat.Builder를 만들기 위해 채널 개념을 사용하는 것은 API Level 26 (Android 8) 버전부터 해당된다.

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NotificationManager

Notification.Builder

• Builder(context: Context!) - API Level 26 (Android 8) 이전 버전
• Builder(context: Context!, channelled: String!) - API Level 26 (Android 8) 부터
  • 앱의 환경설정에서 Notification의 ON/OFF를 설정할 수 있는데, 이때 사용되는 개념이 바로 '채널'이다.

NotificationChannel

• NotificationChannel(id: String!, name: CharSequence!, importance: Int)
• NotificationManager.IMPORTANCE_HIGH: 긴급 상황 & 알림음이 울리며 헤드업으로 표시
• NotificationManager.IMPORTANCE_DEFAULT: 높은 중요도 & 알림음이 울림.
• NotificationManager.IMPORTANCE_LOW: 중간 중요도 & 알림음이 울리지 않음.
• NotificationManager.IMPORTANCE_MIN: 낮은 중요도 & 알림음이 없고 상태표시줄에도 표시되지 않음.

Notification

Notification은 알림에 출력될 이미지, 문자열 등의 정보를 담는 객체

builder.setSmallIcon(android.R.drawable.ic_notification_overlay)
builder.setWhen(System.currentTimeMillis())
builder.setContentTitle("Content Title")
builder.setContentText("Content Message")

실습 예제

package com.tutorial.c74

import android.app.NotificationChannel
import android.app.NotificationManager
import android.graphics.Color
import android.media.AudioAttributes
import android.media.RingtoneManager
import android.os.Build
import android.os.Bundle
import android.widget.Button
import androidx.appcompat.app.AppCompatActivity
import androidx.core.app.NotificationCompat

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val button = findViewById<Button>(R.id.button)
        button.setOnClickListener {
            val manager = getSystemService(NOTIFICATION_SERVICE) as NotificationManager
            val builder: NotificationCompat.Builder
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                val channelId = "one-channel"
                val channelName = "My One Channel"
                val channel = NotificationChannel(
                    channelId,
                    channelName,
                    NotificationManager.IMPORTANCE_HIGH
                )

                channel.description = "My Channel One Description"
                channel.setShowBadge(true)
                val uri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION)
                val audio = AudioAttributes.Builder()
                    .setContentType(AudioAttributes.CONTENT_TYPE_SONIFICATION)
                    .setUsage(AudioAttributes.USAGE_ALARM)
                    .build()
                channel.setSound(uri, audio)
                channel.enableLights(true)
                channel.lightColor = Color.RED
                channel.enableVibration(true)
                channel.vibrationPattern = longArrayOf(100, 200, 100, 200)

                manager.createNotificationChannel(channel)
                builder = NotificationCompat.Builder(this, channelId)
            }else{
                builder = NotificationCompat.Builder(this)
            }

            builder.setSmallIcon(android.R.drawable.ic_notification_overlay)
            builder.setWhen(System.currentTimeMillis())
            builder.setContentTitle("Title")
            builder.setContentText("message")

            manager.notify(1, builder.build())
        }
    }
}

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Notification 구성

터치 이벤트

• static fun getActivity(context: Context!, requestCode: Int, intent: Intent!, flags: Int): PendingIntent!
• static fun getBroadcast(context: Context!, requestCode: Int, intent: Intent!, flags: Int): PendingIntent!
• static fun getService(context: Context!, requestCode: Int, intent: Intent, flags: Int): PendingIntent!

val intent = Intent(this, DetailActivity::class.java)
val pendingIntent = PendingIntent.getActivity(this, 10, intent, PendingIntent.FLAG_UPDATE_CURRENT) 
builder.setContentIntent(pendingIntent) 

액션

Notification에 최대 3개까지의 유저 이벤트를 위한 액션을 추가할 수 있다.

val actionIntent = Intent(this, DetailActivity::class.java)
val actionPendingIntent = PendingIntent.getActivity(this, 20, actionIntent, PendingIntent.FLAG_UPDATE_CURRENT)
builder.addAction(
	NotificationCompat.Action.Builder(
		android.R.drawable.stat_notify_more, 
        "Action", 
        actionPendingIntent
	).build()
)

Progress

Notification으로 작업의 진행 상황을 확인하고 싶을 때

builder.setProgress(100, 0, false)
manager.notify(11, builder.build())
thread {
	for (i in 1..100){
		builder.setProgress(100, i, false)
		manager.notify(11, builder.build())
		SystemClock.sleep(100) 
    } 
}

style

• BigPictureStyle, BigTextStyle, InboxStyle, Message Style

val bigPicture = BitmapFactory.decodeResource(resources, R.drawable.logo_1)
val bigStyle = NotificationCompat.BigPictureStyle()
bigStyle.bigPicture(bigPicture)
builder.setStyle(bigStyle)

실습 예제

package com.tutorial.c75

import android.app.NotificationChannel
import android.app.NotificationManager
import android.app.PendingIntent
import android.content.Intent
import android.graphics.BitmapFactory
import android.os.Build
import android.os.Bundle
import android.widget.Button
import androidx.appcompat.app.AppCompatActivity
import androidx.core.app.NotificationCompat

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val button = findViewById<Button>(R.id.button)
        button.setOnClickListener {
            val manager = getSystemService(NOTIFICATION_SERVICE) as NotificationManager
            val builder: NotificationCompat.Builder
            if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                val channelId = "one"
                val channelName = "channel"
                val channel = NotificationChannel(
                    channelId,
                    channelName,
                    NotificationManager.IMPORTANCE_HIGH
                )
                channel.description = "one description"
                manager.createNotificationChannel(channel)
                builder = NotificationCompat.Builder(this, channelId)
            }else{
                builder = NotificationCompat.Builder(this)
            }

            builder.setSmallIcon(android.R.drawable.ic_notification_overlay)
            builder.setWhen(System.currentTimeMillis())
            builder.setContentTitle("Title")
            builder.setContentText("Text")

            val actionIntent = Intent(this, DetailActivity::class.java)
            val actionPending = PendingIntent.getActivity(this, 20,
                actionIntent, PendingIntent.FLAG_CANCEL_CURRENT)
            builder.setContentIntent(actionPending)

            val actionPending2 = PendingIntent.getActivity(this, 20,
                actionIntent, PendingIntent.FLAG_CANCEL_CURRENT)
            builder.addAction(
                NotificationCompat.Action.Builder(
                    android.R.drawable.stat_notify_more,
                    "Action",
                    actionPending2
                ).build()
            )

            val picture = BitmapFactory.decodeResource(resources, R.drawable.logo_1)
            val style = NotificationCompat.BigPictureStyle()
            style.bigPicture(picture)
            builder.setStyle(style)

            manager.notify(1, builder.build())
        }
    }
}