Flutter web 共享图像适用于 windows 但不适用于 android/ios

Question

I am trying to generate a qr and share it as png. This code works fine for windows but won't work (nothing happens) on ios(safari) and and android(chrome/samsung browser). I'm a begginer in app/web development and have no idea what may be causing this. I have tried to google an answer in a thousand different ways but found nothing.

import 'package:flutter/material.dart';
import 'package:qr_flutter/qr_flutter.dart';
import 'package:flutter/services.dart';
import 'dart:async';
import 'dart:typed_data';
import 'dart:ui';
import 'dart:io';
import 'package:flutter/rendering.dart';
import 'package:path_provider/path_provider.dart';
import 'package:share_plus/share_plus.dart';
import 'package:encrypt/encrypt.dart' as enc;
import 'package:firebase_auth/firebase_auth.dart';
import 'package:http/http.dart';
import 'package:universal_html/html.dart' as html;

class GenerateScreen extends StatefulWidget {
  const GenerateScreen({Key? key, @required this.guestName}) : super(key: key);

  final String? guestName;

  @override
  State<StatefulWidget> createState() => GenerateScreenState();
}

class GenerateScreenState extends State<GenerateScreen> {
  GlobalKey globalKey = GlobalKey();
  List qrFile = [];

  String encryptedText() {
    final String toEncrypt =
        FirebaseAuth.instance.currentUser!.uid + '!' + widget.guestName!;
    print(toEncrypt);
    final key = enc.Key.fromUtf8('Ijh35hYjabf86H7k8jWgETR264Nhflo9');
    final iv = enc.IV.fromLength(16);
    final encrypter = enc.Encrypter(enc.AES(key));
    final encrypted = encrypter.encrypt(toEncrypt, iv: iv);

    return encrypted.base16;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: _contentWidget(),
    );
  }

  Future _captureAndSharePng() async {
    RenderRepaintBoundary boundary =
        globalKey.currentContext!.findRenderObject() as RenderRepaintBoundary;
    var image = await boundary.toImage();
    ByteData? byteData = await image.toByteData(format: ImageByteFormat.png);
    Uint8List pngBytes = byteData!.buffer.asUint8List();
    
    qrFile = [
      html.File([pngBytes], "qr.png", {"type": "image/png"})
    ];

    await html.window.navigator.share({"files": qrFile, "title": "QR"});
  }

  _contentWidget() {
    final bodyHeight = MediaQuery.of(context).size.height -
        MediaQuery.of(context).viewInsets.bottom;
    return Column(
      mainAxisSize: MainAxisSize.min,
      mainAxisAlignment: MainAxisAlignment.spaceEvenly,
      children: <Widget>[
        Padding(
          padding: const EdgeInsets.only(bottom: 100),
          child: TextButton(
              onPressed: () {
                _captureAndSharePng();
              },
              child: Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: const [Text('Compartir QR'), Icon(Icons.share)],
              )),
        ),
        Center(
          child: RepaintBoundary(
            key: globalKey,
            child: Container(
              color: Colors.white,
              child: QrImage(
                backgroundColor: Colors.white,
                data: encryptedText(),
                size: 0.3 * bodyHeight,
              ),
            ),
          ),
        ),
      ],
    );
  }
} ```

Answer 1

html.window.navigator.share is only for the web you have to code with conditions for android and ios or you can use https://pub.dev/packages/share_plus . it supports all the platforms.