flutter - 在URL中使用URL启动器发送电子邮件时出现问题

Question

您好，我尝试启动带配方的电子邮件页面。我尝试了 flutter 的电子邮件发件人，我可以在Android上使用它，但不能在ios上使用。因此，我尝试使用url启动器执行相同的操作，但不能与iOS一起使用。我使用iOS模拟器，可能是这个问题吗？

我使用这个网址启动器示例

mailto:xxxxx@xxxxx.com?subject=News&body=New%20plugin

我有这个错误

[VERBOSE-2:ui_dart_state.cc(148)] Unhandled Exception: Could not launch mailto:xxxx@xxxx.com?subject=News&body=New%20plugin
#0      _menuscreenState._launchURL (package:xxxx/bottom.dart:8285:7)
<asynchronous suspension>
#1      _menuscreenState.build.<anonymous closure>.<anonymous closure> (package:xxxx/bottom.dart:8705:13)

这是url启动器的完整示例

import 'package:flutter/material.dart';
import 'package:url_launcher/url_launcher.dart';

void main() => runApp(MyApp());

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {


  String email="contact@ouiquit.com";
  _launchEmail() async {
    if (await canLaunch("mailto:$email")) {
      await launch("mailto:$email");
    } else {
      throw 'Could not launch';
    }
  }

  @override
  Widget build(BuildContext context) {


    return MaterialApp(
      theme: ThemeData(primaryColor: Colors.red),
      home: Scaffold(
        appBar: AppBar(
          title: Text('test mail'),
          actions: <Widget>[
            IconButton(
              onPressed: _launchEmail,
              icon: Icon(Icons.send),
            )
          ],
        ),


      ),
    );
  }


}

这是错误

[VERBOSE-2:ui_dart_state.cc(148)] Unhandled Exception: MissingPluginException(No implementation found for method canLaunch on channel plugins.flutter.io/url_launcher)
#0      MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:314:7)
<asynchronous suspension>
#1      canLaunch (package:url_launcher/url_launcher.dart:112:25)
<asynchronous suspension>
#2      _MyAppState._launchEmail (package:testmail/main.dart:20:15)
<asynchronous suspension>
#3      _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:654:14)
#4      _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:729:32)
#5      GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:182:24)
#6      TapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:365:11)
#7      TapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:275:7)
#8      PrimaryPointerGestureRecognizer.handleEvent (package:flutter/src/<…>

Answer 1

这对我在Android和iOS设备上均有效:

如果您也有query和subject，请添加body参数。

final Uri params = Uri(
  scheme: 'mailto',
  path: 'email@example.com',
  query: 'subject=App Feedback&body=App Version 3.23', //add subject and body here
);

var url = params.toString();
if (await canLaunch(url)) {
  await launch(url);
} else {
  throw 'Could not launch $url';
}