migrating the plugin to the V2 embedding

android/src/main/java/yy/inc/flutter_custom_dialog/FlutterCustomDialogPlugin.java

@@ -1,25 +1,38 @@
 package yy.inc.flutter_custom_dialog;
 
+import androidx.annotation.NonNull;
+
+import io.flutter.embedding.engine.plugins.FlutterPlugin;
 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;
 
-/** FlutterCustomDialogPlugin */
-public class FlutterCustomDialogPlugin implements MethodCallHandler {
-  /** Plugin registration. */
-  public static void registerWith(Registrar registrar) {
-    final MethodChannel channel = new MethodChannel(registrar.messenger(), "flutter_custom_dialog");
-    channel.setMethodCallHandler(new FlutterCustomDialogPlugin());
+/** UntitledPlugin */
+public class FlutterCustomDialogPlugin implements FlutterPlugin, MethodCallHandler {
+  /// The MethodChannel that will the communication between Flutter and native Android
+  ///
+  /// This local reference serves to register the plugin with the Flutter Engine and unregister it
+  /// when the Flutter Engine is detached from the Activity
+  private MethodChannel channel;
+
+  @Override
+  public void onAttachedToEngine(@NonNull FlutterPluginBinding flutterPluginBinding) {
+    channel = new MethodChannel(flutterPluginBinding.getBinaryMessenger(), "untitled");
+    channel.setMethodCallHandler(this);
   }
 
   @Override
-  public void onMethodCall(MethodCall call, Result result) {
+  public void onMethodCall(@NonNull MethodCall call, @NonNull Result result) {
     if (call.method.equals("getPlatformVersion")) {
       result.success("Android " + android.os.Build.VERSION.RELEASE);
     } else {
       result.notImplemented();
     }
   }
+
+  @Override
+  public void onDetachedFromEngine(@NonNull FlutterPluginBinding binding) {
+    channel.setMethodCallHandler(null);
+  }
 }

example/android/app/src/main/AndroidManifest.xml

@@ -1,33 +1,42 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="yy.inc.flutter_custom_dialog_example">
+          package="yy.inc.flutter_custom_dialog_example">
 
-    <!-- io.flutter.app.FlutterApplication is an android.app.Application that
-         calls FlutterMain.startInitialization(this); in its onCreate method.
-         In most cases you can leave this as-is, but you if you want to provide
-         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="flutter_custom_dialog_example"
-        android:icon="@mipmap/ic_launcher">
+            android:label="flutter_custom_dialog_example"
+            android:icon="@mipmap/ic_launcher">
         <activity
-            android:name=".MainActivity"
-            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). -->
+                android:name=".MainActivity"
+                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">
+            <!-- Specifies an Android theme to apply to this Activity as soon as
+                 the Android process has started. This theme is visible to the user
+                 while the Flutter UI initializes. After that, this theme continues
+                 to determine the Window background behind the Flutter UI. -->
             <meta-data
-                android:name="io.flutter.app.android.SplashScreenUntilFirstFrame"
-                android:value="true" />
+                    android:name="io.flutter.embedding.android.NormalTheme"
+                    android:resource="@style/NormalTheme"
+            />
+            <!-- Displays an Android View that continues showing the launch screen
+                 Drawable until Flutter paints its first frame, then this splash
+                 screen fades out. A splash screen is useful to avoid any visual
+                 gap between the end of Android's launch screen and the painting of
+                 Flutter's first frame. -->
+            <meta-data
+                    android:name="io.flutter.embedding.android.SplashScreenDrawable"
+                    android:resource="@drawable/launch_background"
+            />
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
         </activity>
+        <!-- Don't delete the meta-data below.
+     This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
+        <meta-data
+                android:name="flutterEmbedding"
+                android:value="2"/>
     </application>
 </manifest>

example/android/app/src/main/java/yy/inc/flutter_custom_dialog_example/MainActivity.java

@@ -1,13 +1,6 @@
 package yy.inc.flutter_custom_dialog_example;
 
-import android.os.Bundle;
-import io.flutter.app.FlutterActivity;
-import io.flutter.plugins.GeneratedPluginRegistrant;
+import io.flutter.embedding.android.FlutterActivity;
 
 public class MainActivity extends FlutterActivity {
-  @Override
-  protected void onCreate(Bundle savedInstanceState) {
-    super.onCreate(savedInstanceState);
-    GeneratedPluginRegistrant.registerWith(this);
-  }
 }