Added implementation of notification to flutter_template.

Author: daisukenishino2

Template/MobileTemplate/flutter_template/android/app/build.gradle

@@ -24,6 +24,7 @@ if (flutterVersionName == null) {
 apply plugin: 'com.android.application'
 apply plugin: 'kotlin-android'
 apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
+apply plugin: 'com.google.gms.google-services'
 
 android {
     compileSdkVersion 30
@@ -35,7 +36,7 @@ android {
     defaultConfig {
         // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
         applicationId "com.opentouryo.flutter_template"
-        minSdkVersion 16
+        minSdkVersion 23 // 16 -> 23
         targetSdkVersion 30
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName
@@ -60,4 +61,5 @@ flutter {
 
 dependencies {
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+    implementation "com.google.firebase:firebase-messaging:22.0.0"
 }

Template/MobileTemplate/flutter_template/android/app/google-services.json

@@ -0,0 +1 @@
+�u��������B

Template/MobileTemplate/flutter_template/android/app/src/main/AndroidManifest.xml

@@ -1,9 +1,16 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.opentouryo.flutter_template">
    <application
+        android:name=".Application"
         android:label="flutter_template"
         android:icon="@mipmap/ic_launcher"
         android:networkSecurityConfig="@xml/network_security_config">
+       <meta-data
+           android:name="com.google.firebase.messaging.default_notification_icon"
+           android:resource="@drawable/notification_icon" />
+       <meta-data
+           android:name="com.google.firebase.messaging.default_notification_color"
+           android:resource="@color/colorPrimary" />
         <activity
             android:name=".MainActivity"
             android:launchMode="singleTop"
@@ -46,6 +53,11 @@
                 <category android:name="android.intent.category.BROWSABLE" />
                 <data android:scheme="http" android:host="opentouryo.com" />
             </intent-filter>
+            <!-- FLUTTER NOTIFICATION -->
+            <intent-filter>
+                <action android:name="FLUTTER_NOTIFICATION_CLICK" />
+                <category android:name="android.intent.category.DEFAULT" />
+            </intent-filter>
         </activity>
         <!-- Don't delete the meta-data below.
              This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->

Template/MobileTemplate/flutter_template/android/app/src/main/kotlin/com/opentouryo/flutter_template/Application.kt

@@ -0,0 +1,21 @@
+package com.opentouryo.flutter_template
+
+import io.flutter.app.FlutterApplication
+import io.flutter.plugin.common.PluginRegistry
+import io.flutter.plugin.common.PluginRegistry.PluginRegistrantCallback
+import io.flutter.plugins.firebase.messaging.FlutterFirebaseMessagingBackgroundService
+import io.flutter.plugins.firebase.messaging.FlutterFirebaseMessagingPlugin
+
+class Application : FlutterApplication(), PluginRegistrantCallback {
+    override fun onCreate() {
+        super.onCreate()
+        FlutterFirebaseMessagingBackgroundService.setPluginRegistrant(this)
+    }
+
+    override fun registerWith(registry: PluginRegistry?) {
+        val key: String? = FlutterFirebaseMessagingPlugin::class.java.canonicalName
+        if (!registry?.hasPlugin(key)!!) {
+            FlutterFirebaseMessagingPlugin.registerWith(registry?.registrarFor("io.flutter.plugins.firebase.messaging.FlutterFirebaseMessagingPlugin"));
+        }
+    }
+}

Template/MobileTemplate/flutter_template/android/app/src/main/res/drawable/notification_icon.png

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="colorPrimary">#e26338</color>
+</resources>

Template/MobileTemplate/flutter_template/android/app/src/main/res/values/colors.xml

@@ -8,6 +8,7 @@ buildscript {
     dependencies {
         classpath 'com.android.tools.build:gradle:4.1.0'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+        classpath 'com.google.gms:google-services:4.3.5'
     }
 }
 

Template/MobileTemplate/flutter_template/android/build.gradle

@@ -4,12 +4,16 @@
 
 // ignore_for_file: lines_longer_than_80_chars
 
+import 'package:firebase_core_web/firebase_core_web.dart';
+import 'package:firebase_messaging_web/firebase_messaging_web.dart';
 import 'package:url_launcher_web/url_launcher_web.dart';
 
 import 'package:flutter_web_plugins/flutter_web_plugins.dart';
 
 // ignore: public_member_api_docs
 void registerPlugins(Registrar registrar) {
+  FirebaseCoreWeb.registerWith(registrar);
+  FirebaseMessagingWeb.registerWith(registrar);
   UrlLauncherPlugin.registerWith(registrar);
   registrar.registerMessageHandler();
 }