[ADD] notifications

Author: Ranzed

fcm/app/build.gradle

@@ -35,10 +35,10 @@ android {
 dependencies {
 
     implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
-    implementation 'androidx.core:core-ktx:1.3.1'
-    implementation 'androidx.appcompat:appcompat:1.2.0'
-    implementation 'com.google.android.material:material:1.2.1'
-    implementation 'androidx.constraintlayout:constraintlayout:2.0.1'
+    implementation 'androidx.core:core-ktx:1.5.0'
+    implementation 'androidx.appcompat:appcompat:1.3.0'
+    implementation 'com.google.android.material:material:1.3.0'
+    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
 
     // firebase
     implementation platform('com.google.firebase:firebase-bom:28.1.0')

fcm/app/src/main/java/com/ranzed/fcm/App.kt

@@ -1,13 +1,13 @@
 package com.ranzed.fcm
 
 import android.app.Application
-import android.util.Log
+import com.ranzed.fcm.notification.NotificationService
 
 class App : Application() {
 
     override fun onCreate() {
         super.onCreate()
+        NotificationService.initialize(this)
     }
 
-
 }

fcm/app/src/main/java/com/ranzed/fcm/activity/MessageActivity.kt

@@ -2,16 +2,20 @@ package com.ranzed.fcm.activity
 
 import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
-import android.widget.TextView
+import android.view.View
+import androidx.appcompat.widget.AppCompatButton
 import com.ranzed.fcm.R
+import com.ranzed.fcm.notification.NotificationService
 
 class MessageActivity : AppCompatActivity() {
 
-    private var helloText : TextView? = null
+    private var createNotification : AppCompatButton? = null
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_message)
-        helloText = findViewById(R.id.hello)
+        createNotification = findViewById(R.id.btn_create_notification)
+        createNotification?.setOnClickListener { view : View ->
+            NotificationService.createNotification("123", "456", this)}
     }
 }

fcm/app/src/main/java/com/ranzed/fcm/notification/NotificationService.kt

@@ -0,0 +1,55 @@
+package com.ranzed.fcm.notification
+
+import android.app.NotificationChannel
+import android.app.NotificationManager
+import android.content.Context
+import android.os.Build
+import androidx.core.app.NotificationCompat
+import com.ranzed.fcm.R
+
+object NotificationService {
+
+    private val CHANNEL_ID = "fcm_channel_id"
+    private var initialized = false
+
+    fun createNotification(title: String, message : String, ctx : Context) {
+        if (!initialized)
+            return
+
+        val builder = NotificationCompat.Builder(ctx, CHANNEL_ID)
+            .setSmallIcon(R.mipmap.ic_launcher)
+            .setContentTitle(title)
+            .setContentText(message)
+
+        val notificationManager = ctx.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
+        notificationManager.notify(0, builder.build())
+
+    }
+
+    fun initialize(ctx : Context) {
+        if (initialized)
+            return
+
+        createNotificationChannel(ctx)
+        initialized = true
+    }
+
+    private fun createNotificationChannel(ctx : Context) {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.O)
+            return
+
+        val notificationManager = ctx.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
+
+        val c = notificationManager.getNotificationChannel(CHANNEL_ID)
+        if (c != null)
+            return
+
+        val channel = NotificationChannel(CHANNEL_ID,
+            ctx.getString(R.string.notification_channel_name),
+            NotificationManager.IMPORTANCE_DEFAULT)
+        channel.description = ctx.getString(R.string.notification_channel_description)
+
+        notificationManager.createNotificationChannel(channel)
+    }
+
+}

fcm/app/src/main/res/layout/activity_message.xml

@@ -6,6 +6,15 @@
     android:layout_height="match_parent"
     tools:context=".activity.MessageActivity">
 
+    <Button
+        android:id="@+id/btn_create_notification"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
     <TextView
         android:id="@+id/hello"
         android:layout_width="wrap_content"

fcm/app/src/main/res/values/strings.xml

@@ -1,4 +1,8 @@
 <resources>
     <string name="app_name">Cloud Messaging</string>
     <string name="hello_message">Hello world</string>
+
+    <string name="notification_channel_name">Fcm channel</string>
+    <string name="notification_channel_description">Fcm channel description</string>
+
 </resources>