diff --git a/README.md b/README.md
index 7c26f4e..5bd052e 100644
--- a/README.md
+++ b/README.md
@@ -47,7 +47,7 @@ This plugin supported custom layout. You need to create a layout file.
 
 ### Android
 You can use anything if the parent is a ViewGroup.
-The example uses RelativeLayout.
+The example uses ConstraintLayout.
 
 Use [`com.google.android.gms.ads.formats.UnifiedNativeAdView`](https://developers.google.com/android/reference/com/google/android/gms/ads/formats/UnifiedNativeAdView) for the parent.
 
@@ -68,9 +68,10 @@ Use [`com.google.android.gms.ads.formats.MediaView`](https://developers.google.c
     ...
     
     <!-- ViewGroup -->
-    <RelativeLayout
+    <androidx.constraintlayout.widget.ConstraintLayout
+        android:id="@+id/relativeLayout"
         android:layout_width="match_parent"
-        android:layout_height="wrap_content">
+        android:layout_height="match_parent">
         
         ...
 
@@ -213,6 +214,11 @@ Receive callbacks for some events by passing to the NativeAdView constructor
 - onAdLeftApplication
 - onAdLoaded
 
+## Reference
+- Mobile Ads SDK Release Notes
+  - [Android](https://developers.google.com/admob/android/rel-notes)
+  - [iOS](https://developers.google.com/admob/ios/rel-notes)
+
 ## Limitations
 
 This is just an initial version of the plugin. There are still some
diff --git a/android/src/main/kotlin/sakebook/github/com/native_ads/NativeAdsPlugin.kt b/android/src/main/kotlin/sakebook/github/com/native_ads/NativeAdsPlugin.kt
index fbd6884..f7669c8 100644
--- a/android/src/main/kotlin/sakebook/github/com/native_ads/NativeAdsPlugin.kt
+++ b/android/src/main/kotlin/sakebook/github/com/native_ads/NativeAdsPlugin.kt
@@ -1,35 +1,50 @@
 package sakebook.github.com.native_ads
 
 import com.google.android.gms.ads.MobileAds
+import io.flutter.embedding.engine.plugins.FlutterPlugin
+import io.flutter.embedding.engine.plugins.activity.ActivityAware
+import io.flutter.embedding.engine.plugins.activity.ActivityPluginBinding
 import io.flutter.plugin.common.MethodCall
 import io.flutter.plugin.common.MethodChannel
 import io.flutter.plugin.common.MethodChannel.MethodCallHandler
 import io.flutter.plugin.common.MethodChannel.Result
-import io.flutter.plugin.common.PluginRegistry.Registrar
-
-class NativeAdsPlugin : MethodCallHandler {
-
-    companion object {
-        private lateinit var registrar: Registrar
-        @JvmStatic
-        fun registerWith(registrar: Registrar) {
-            val channel = MethodChannel(registrar.messenger(), "native_ads")
-            channel.setMethodCallHandler(NativeAdsPlugin())
-            this.registrar = registrar
-            registrar
-                    .platformViewRegistry()
-                    .registerViewFactory(
-                            "com.github.sakebook.android/unified_ad_layout", UnifiedAdLayoutFactory(registrar.messenger()))
-        }
+
+class NativeAdsPlugin : FlutterPlugin, ActivityAware, MethodCallHandler {
+
+    // for future use
+    private var channel: MethodChannel? = null
+
+    override fun onAttachedToEngine(binding: FlutterPlugin.FlutterPluginBinding) {
+        channel = MethodChannel(binding.binaryMessenger, "native_ads")
+        channel?.setMethodCallHandler(this)
+        binding.platformViewRegistry
+                .registerViewFactory("com.github.sakebook.android/unified_ad_layout",
+                        UnifiedAdLayoutFactory(binding.binaryMessenger))
+    }
+
+    override fun onAttachedToActivity(binding: ActivityPluginBinding) {
+        MobileAds.initialize(binding.activity)
     }
 
     override fun onMethodCall(call: MethodCall, result: Result) {
         when (call.method) {
             "initialize" -> {
-                MobileAds.initialize(registrar.context())
                 result.success(true)
             }
             else -> result.notImplemented()
         }
     }
-}
+
+    override fun onDetachedFromActivity() {
+    }
+
+    override fun onDetachedFromEngine(binding: FlutterPlugin.FlutterPluginBinding) {
+        channel?.setMethodCallHandler(null)
+    }
+
+    override fun onReattachedToActivityForConfigChanges(binding: ActivityPluginBinding) {
+    }
+
+    override fun onDetachedFromActivityForConfigChanges() {
+    }
+}
\ No newline at end of file
diff --git a/android/src/main/kotlin/sakebook/github/com/native_ads/UnifiedAdLayout.kt b/android/src/main/kotlin/sakebook/github/com/native_ads/UnifiedAdLayout.kt
index da796e0..bffed2a 100644
--- a/android/src/main/kotlin/sakebook/github/com/native_ads/UnifiedAdLayout.kt
+++ b/android/src/main/kotlin/sakebook/github/com/native_ads/UnifiedAdLayout.kt
@@ -16,7 +16,12 @@ import io.flutter.plugin.common.BinaryMessenger
 import io.flutter.plugin.common.MethodChannel
 import io.flutter.plugin.platform.PlatformView
 
-class UnifiedAdLayout(context: Context, messenger: BinaryMessenger, id: Int, arguments: HashMap<String, String>) : PlatformView {
+class UnifiedAdLayout(
+    context: Context,
+    messenger: BinaryMessenger,
+    id: Int,
+    arguments: HashMap<String, String>
+) : PlatformView {
 
     private val hostPackageName = arguments["package_name"]
     private val layoutRes = context.resources.getIdentifier(arguments["layout_name"], "layout", hostPackageName)
diff --git a/example/android/app/src/main/AndroidManifest.xml b/example/android/app/src/main/AndroidManifest.xml
index ff68206..118fadb 100644
--- a/example/android/app/src/main/AndroidManifest.xml
+++ b/example/android/app/src/main/AndroidManifest.xml
@@ -1,4 +1,5 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
     package="sakebook.github.com.native_ads_example">
 
     <!-- io.flutter.app.FlutterApplication is an android.app.Application that
@@ -7,28 +8,32 @@
          additional functionality it is fine to subclass or reimplement
          FlutterApplication and put your custom class here. -->
     <application
-        android:name="io.flutter.app.FlutterApplication"
         android:label="native_ads_example"
         android:icon="@mipmap/ic_launcher">
         <activity
-            android:name=".MainActivity"
+            android:name="io.flutter.embedding.android.FlutterActivity"
             android:launchMode="singleTop"
             android:theme="@style/LaunchTheme"
             android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
             android:hardwareAccelerated="true"
             android:windowSoftInputMode="adjustResize">
-            <!-- This keeps the window background of the activity showing
-                 until Flutter renders its first frame. It can be removed if
-                 there is no splash screen (such as the default splash screen
-                 defined in @style/LaunchTheme). -->
+
+            <meta-data
+                android:name="io.flutter.embedding.android.SplashScreenDrawable"
+                android:resource="@drawable/splash_background" />
+
             <meta-data
-                android:name="io.flutter.app.android.SplashScreenUntilFirstFrame"
-                android:value="true" />
+                android:name="io.flutter.embedding.android.NormalTheme"
+                android:resource="@style/NormalTheme" />
+
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
         </activity>
+        <meta-data
+            android:name="flutterEmbedding"
+            android:value="2" />
         <meta-data
             android:name="com.google.android.gms.ads.APPLICATION_ID"
             android:value="ca-app-pub-3940256099942544~3347511713"/>
diff --git a/example/android/app/src/main/kotlin/sakebook/github/com/native_ads_example/MainActivity.kt b/example/android/app/src/main/kotlin/sakebook/github/com/native_ads_example/MainActivity.kt
deleted file mode 100644
index f7e2ab2..0000000
--- a/example/android/app/src/main/kotlin/sakebook/github/com/native_ads_example/MainActivity.kt
+++ /dev/null
@@ -1,13 +0,0 @@
-package sakebook.github.com.native_ads_example
-
-import android.os.Bundle
-
-import io.flutter.app.FlutterActivity
-import io.flutter.plugins.GeneratedPluginRegistrant
-
-class MainActivity: FlutterActivity() {
-  override fun onCreate(savedInstanceState: Bundle?) {
-    super.onCreate(savedInstanceState)
-    GeneratedPluginRegistrant.registerWith(this)
-  }
-}
diff --git a/example/android/app/src/main/res/drawable/launch_background.xml b/example/android/app/src/main/res/drawable/launch_background.xml
deleted file mode 100644
index 304732f..0000000
--- a/example/android/app/src/main/res/drawable/launch_background.xml
+++ /dev/null
@@ -1,12 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- Modify this file to customize your launch splash screen -->
-<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
-    <item android:drawable="@android:color/white" />
-
-    <!-- You can insert your own image assets here -->
-    <!-- <item>
-        <bitmap
-            android:gravity="center"
-            android:src="@mipmap/launch_image" />
-    </item> -->
-</layer-list>
diff --git a/example/android/app/src/main/res/drawable/splash_background.xml b/example/android/app/src/main/res/drawable/splash_background.xml
new file mode 100644
index 0000000..5782842
--- /dev/null
+++ b/example/android/app/src/main/res/drawable/splash_background.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:drawable="@android:color/white" />
+</layer-list>
diff --git a/example/android/app/src/main/res/values/styles.xml b/example/android/app/src/main/res/values/styles.xml
index 00fa441..253fb8c 100644
--- a/example/android/app/src/main/res/values/styles.xml
+++ b/example/android/app/src/main/res/values/styles.xml
@@ -1,8 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
     <style name="LaunchTheme" parent="@android:style/Theme.Black.NoTitleBar">
-        <!-- Show a splash screen on the activity. Automatically removed when
-             Flutter draws its first frame -->
-        <item name="android:windowBackground">@drawable/launch_background</item>
+        <item name="android:windowBackground">@android:color/white</item>
+        <item name="android:windowTranslucentStatus">true</item>
+    </style>
+    <style name="NormalTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <item name="android:windowBackground">@android:color/white</item>
     </style>
 </resources>