[infra_ui][keyboard] Change android plugin to java

app_flowy/packages/flowy_infra_ui/android/build.gradle

@@ -1,8 +1,7 @@
 group 'com.example.flowy_infra_ui'
-version '1.0-SNAPSHOT'
+version '1.0'
 
 buildscript {
-    ext.kotlin_version = '1.3.50'
     repositories {
         google()
         mavenCentral()
@@ -10,7 +9,6 @@ buildscript {
 
     dependencies {
         classpath 'com.android.tools.build:gradle:4.1.0'
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }
 
@@ -22,7 +20,6 @@ rootProject.allprojects {
 }
 
 apply plugin: 'com.android.library'
-apply plugin: 'kotlin-android'
 
 android {
     compileSdkVersion 30
@@ -32,19 +29,7 @@ android {
         targetCompatibility JavaVersion.VERSION_1_8
     }
 
-    kotlinOptions {
-        jvmTarget = '1.8'
-    }
-
-    sourceSets {
-        main.java.srcDirs += 'src/main/kotlin'
-    }
-
     defaultConfig {
         minSdkVersion 16
     }
 }
-
-dependencies {
-    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
-}

app_flowy/packages/flowy_infra_ui/android/src/main/java/com/example/flowy_infra_ui/FlowyInfraUiPlugin.java

@@ -0,0 +1,38 @@
+package com.example.flowy_infra_ui;
+
+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;
+
+/** FlowyInfraUiPlugin */
+public class FlowyInfraUiPlugin 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(), "flowy_infra_ui");
+    channel.setMethodCallHandler(this);
+  }
+
+  @Override
+  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);
+  }
+}

app_flowy/packages/flowy_infra_ui/android/src/main/kotlin/com/example/flowy_infra_ui/FlowyInfraUiPlugin.kt

@@ -1,35 +0,0 @@
-package com.example.flowy_infra_ui
-
-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
-
-/** FlowyInfraUiPlugin */
-class FlowyInfraUiPlugin: 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 lateinit var channel : MethodChannel
-
-  override fun onAttachedToEngine(@NonNull flutterPluginBinding: FlutterPlugin.FlutterPluginBinding) {
-    channel = MethodChannel(flutterPluginBinding.binaryMessenger, "flowy_infra_ui")
-    channel.setMethodCallHandler(this)
-  }
-
-  override fun onMethodCall(@NonNull call: MethodCall, @NonNull result: Result) {
-    if (call.method == "getPlatformVersion") {
-      result.success("Android ${android.os.Build.VERSION.RELEASE}")
-    } else {
-      result.notImplemented()
-    }
-  }
-
-  override fun onDetachedFromEngine(@NonNull binding: FlutterPlugin.FlutterPluginBinding) {
-    channel.setMethodCallHandler(null)
-  }
-}

app_flowy/packages/flowy_infra_ui/example/android/app/src/main/java/com/example/flowy_infra_ui_example/MainActivity.java

@@ -0,0 +1,6 @@
+package com.example.flowy_infra_ui_example;
+
+import io.flutter.embedding.android.FlutterActivity;
+
+public class MainActivity extends FlutterActivity {
+}