新版Flutter集成到已有Android项目的实现

setBinding(new Binding([gradle:this]))
evaluate(
  new File(
    settingsDir,
    'flutter_module/.android/include_flutter.groovy'
  )
)
include ':flutter_module'

implementation project(path: ':flutter')

public class MVApplication extends Application {
 private static MVApplication instance;
 public static MVApplication getInstance(){
  return instance;
 }
 @Override
 public void onCreate() {
  super.onCreate();
  FlutterMain.Settings settings=new FlutterMain.Settings();
  settings.setLogTag("MyFlutter");
  FlutterMain.startInitialization(this,settings);
  String[] args = {"info", "data"};
  FlutterMain.ensureInitializationComplete(this,args);
  instance=this;
 }
}

public class MyFlutterActivity extends FragmentActivity {
 @Override
 protected void onCreate(@Nullable Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.flutter_layout);
  //FlutterFragment fragment=new FlutterFragment();
  FlutterFragment fragment=FlutterFragment.withNewEngine().initialRoute("home").build();
  getSupportFragmentManager().beginTransaction().add(R.id.flutter_container, fragment).commit();
 }
}

public class MyFlutterActivity extends FragmentActivity {
 @Override
 protected void onCreate(@Nullable Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.flutter_layout);
  FrameLayout frameLayout=findViewById(R.id.flutter_container);
  ProgressBar progress=findViewById(R.id.progress);
  //创建FlutterView
  FlutterView flutterView=new FlutterView(this);
  //创建FlutterView首帧渲染完成监听
  flutterView.addFirstFrameListener(new FlutterView.FirstFrameListener() {
   @Override
   public void onFirstFrame() {
    //隐藏进度条，显示FlutterView
    progress.setVisibility(View.GONE);
    frameLayout.setVisibility(View.VISIBLE);
   }
  });
  //创建dart代码执行器
  DartExecutor executor=flutterView.getDartExecutor();
  //执行main.dart中的main函数
  executor.executeDartEntrypoint(
    new DartExecutor.DartEntrypoint(FlutterMain.findAppBundlePath(),
      "main"));
  //将FlutterView添加到布局中
  ViewGroup.LayoutParams layoutParams=new LinearLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT,
    FrameLayout.LayoutParams.MATCH_PARENT);
  frameLayout.addView(flutterView);
 }
}

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="match_parent"
 android:layout_height="match_parent">
 <FrameLayout
  android:id="@+id/flutter_container"
  android:visibility="invisible"
  android:layout_width="match_parent"
  android:layout_height="match_parent">

 </FrameLayout>
 <ProgressBar
  android:id="@+id/progress"
  android:layout_width="45dp"
  android:layout_height="45dp"
  android:layout_centerVertical="true"
  android:layout_centerHorizontal="true"
  android:visibility="visible"
  >
 </ProgressBar>
</RelativeLayout>