在Flutter中通过插件使用Android的Fragment 时，可以通过Platform Views的方式实现，即在Flutter中嵌入Native View。

首先，需要在Flutter插件的主要文件（例如Java或Kotlin）中声明平台视图：

package com.example.my_flutter_plugin;

import android.content.Context;
import android.widget.FrameLayout;

import io.flutter.embedding.android.FlutterView;
import io.flutter.plugin.common.MethodCall;
import io.flutter.plugin.common.MethodChannel;
import io.flutter.plugin.platform.PlatformView;

public class MyFlutterFragmentView implements PlatformView {
    private final FrameLayout frameLayout;
    private final FlutterView flutterView;

    MyFlutterFragmentView(Context context, int id, Object args, MethodChannel methodChannel) {
        frameLayout = new FrameLayout(context);

        flutterView = new FlutterView(context);
        frameLayout.addView(flutterView);
        FlutterFragmentPlugin.create(flutterView, id, args, methodChannel);
    }

    @Override
    public View getView() {
        return frameLayout;
    }

    @Override
    public void dispose() {
        flutterView.destroy();
    }
}

然后，在Flutter插件中创建平台视图的实例：

/// 创建PlatformView
Future createView