Send data between WebView & Android app

Processing for Android
3

I’ve updated my code to look like this :-

import android.widget.Toast;
import android.webkit.JavascriptInterface;
import android.content.res.AssetManager;
import android.webkit.WebViewClient;
import android.os.Looper;
import android.content.Context;
import android.view.ViewGroup.LayoutParams;
import android.webkit.WebView;
import android.view.ViewGroup;
import android.app.Activity;
import android.widget.RelativeLayout;
import android.widget.FrameLayout;
import java.io.File;
import android.os.Bundle;
import android.os.Environment;

FrameLayout fl;
Activity act;
WebView web;
Context context;
WebViewClient wbc;///if you want to use chrome
File[] files;//if you want to list files
String[] filesPath;//if you want to list subfolders
 
public class JavaScriptInterface {
    Context mContext;

    /** Instantiate the interface and set the context */
    JavaScriptInterface(Context c) {
        mContext = c;
    }

    /** Show a toast from the web page */
    @JavascriptInterface
    public void showToast(String toast) {
        Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();
    }
}
 
void settings(){
  fullScreen();
};
 
public void onStart() {
  super.onStart();
 
  act = this.getActivity();
  wbc = new WebViewClient();
  web = new WebView(act);
  web.setLayoutParams(new RelativeLayout.LayoutParams( RelativeLayout.LayoutParams.MATCH_PARENT,RelativeLayout.LayoutParams.MATCH_PARENT));
  web.setWebViewClient(wbc);
  web.getSettings().setJavaScriptEnabled(true);
  web.loadUrl("file:///android_asset/index.html");
  fl = (FrameLayout)act.getWindow().getDecorView().getRootView();
  fl.addView(web);
  web.addJavascriptInterface(new JavaScriptInterface(this), "Android");
};
 
void setup(){
  background(255,0,0);
};
 
void draw(){
   background(255,0,0);
};

on the last line in onStart() it shows error;; i dont undersatnd why??