Open PDf inside a webview

[Ambika chamoli]

How can I show or download pdf files inside a Flutter_webview?

I'm using flutter webview in this how can i show or download pdf file. If any one knows about this please share the code. Thanks

My Code is : 

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:flutter_webview_plugin/flutter_webview_plugin.dart';
import 'package:lg_listening/lg_dashboard/LgDashboardPage.dart';
import 'package:lg_listening/lg_dashboard/utils/app_shared_preferences.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:url_launcher/url_launcher.dart';



class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);
  final String title;

  @override
  NewWeb createState() => NewWeb();
}

class NewWeb extends State<MyHomePage> {

  String userId="";
  String userName="";
  String userType="";
  String userDeptCode="";
  String UserDeptdes="";
  String userMinid="";
  String userRepId="";
  String Userflag="";
  String UserLaid="";
  String userMPMid="";
  String userTypeCat="";
  String Userlmpflag="";
  String userDivid="";
  String UserSubdivid="";
  String userCheckId="";

  String userIds ;
  String userTypes ;
  String userRepIds ;
  String userMPMids ;
  String userDeptCodes ;
  String userTypeCats ;
  String userDivids;
  String userCheckIds ;
  String userMinids ;
  String selectedUrl;

  //String url = 'http://listeningpostdelhilg.in/AuPages/DashBoard/PendencyAgeWiseMobileApp.aspx?Q_usertype=4&Q_repoffid=0&Q_mpmlaid=&Q_Deptcode=92&Q_UserTypeCat=&Q_divid=&Q_chk_checked=&Q_minid=0&Q_userid=hodrev&Q_Secretkey=QXl1c2hQcmF2ZWVuTWFuaW5kcmFOaWNAMTIz';
  final webview = FlutterWebviewPlugin();
  StreamSubscription<String> _onWebViewUrlChanged;


  @override
  void dispose() {
// TODO: implement dispose
    webview.dispose();
    super.dispose();
  }

 @override
  void initState() {
    super.initState();
    _getUserPreferenceData();
    _onWebViewUrlChanged = FlutterWebviewPlugin().onUrlChanged.listen((String url) {
          if (url.contains('.pdf')) {
            launchURL(url);
          }
        });
   // webview.close();
// TODO: implement initState

  }
  Future _getUserPreferenceData() async {
    userId = await PreferenceHelper.getUSERID();
    userType = await PreferenceHelper.getUserType();
    userRepId = await PreferenceHelper.getUSERREPID();
    userMPMid = await PreferenceHelper.getUSERMPMID();
    userDeptCode = await PreferenceHelper.getUSERDEPTCODE();
    userTypeCat = await PreferenceHelper.getUSERTYPECAT();
    userDivid = await PreferenceHelper.getUSERDIVID();
    userCheckId = await PreferenceHelper.getUSERCHECKED();
    userMinid = await PreferenceHelper.getUSERMINID();

    setState(() {
      selectedUrl = 'http://AuPages/DashBoard/PendencyAgeWiseMobileApp.aspx?Q_usertype=$userType&Q_repoffid=$userRepId&Q_mpmlaid=$userMPMid&Q_Deptcode=$userDeptCode&Q_UserTypeCat=$userTypeCat&Q_divid=$userDivid&Q_chk_checked=&Q_minid=$userMinid&Q_userid=$userId&Q_Secretkey=QXl1c2hQcmF2ZWVuTWFuaW5kcmFOaWNAMTIz';
    });

  }
// selected URL : http://listeningpostdelhilg.in/lgservice.asmx/PendencyAgeWiseMobileApp?
  @override
  Widget build(BuildContext context) {
// TODO: implement build
    return Scaffold(
        appBar: AppBar(
          title: Text(" Dashboard"),
        ),

      body: Container(
        child: selectedUrl == ""
            ? Center(
          child: Row(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              CircularProgressIndicator(
                  valueColor: AlwaysStoppedAnimation(Colors.blue),
                  strokeWidth: 5.0)
            ],
          ),
        )
            : WebviewScaffold(
          url: selectedUrl,
// url: 'http://listeningpostdelhilg.in/AuPages/DashBoard/PendencyAgeWiseMobileApp.aspx?Q_usertype=4&Q_repoffid=0&Q_mpmlaid=&Q_Deptcode=92&Q_UserTypeCat=&Q_divid=&Q_chk_checked=&Q_minid=0&Q_userid=hodrev&Q_Secretkey=QXl1c2hQcmF2ZWVuTWFuaW5kcmFOaWNAMTIz',
          withJavascript: true,
          withLocalStorage: true,
          withZoom: true,
          appCacheEnabled: true,
          clearCookies: true,
          clearCache: true,
          allowFileURLs: true,
          initialChild: Container(
            color: Colors.white,
            child: const Center(
              child: Text(
                'Loading......',
                style: TextStyle(color: Colors.black),
              ),
            ),
          ),
        ),
      ),
        );
    return null;
  }
  void launchURL(String url) async {
    if (await canLaunch(url)) {
      await launch(url);
    } else {
      throw 'Could not launch $url';
    }
  }
}