网络安全配置不允许 HTTP 访问

如果将图像连接到协议为HTTPS的地址，则一切正常。

final String _path = 'https://flutter.github.io/assets-for-api-docs/assets/widgets/owl-2.jpg';

如果您将图像连接到协议为HTTP的地址，那么一切都不起作用。

final String _path = 'http://fr38060s.bget.ru/_html/perform/img/car.jpg';

以前，这个问题是通过这种方式解决的。在文件中，在应用程序 AndroidManifest.xml标记中，添加了该属性

android:usesCleartextTraffic="true"

现在，如果您单击链接，一切都会有所不同

网络安全配置

我在android/app/src/main/res文件夹中创建了xml文件夹

在其中创建了一个network-security-config.xml文件

<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
 <base-config cleartextTrafficPermitted="true" />
</network-security-config>

在AndroidManifest.xml添加

android:networkSecurityConfig="@xml/network-security-config"

这是完整的代码

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
 package="com.example.f1">

 <application
  android:networkSecurityConfig="@xml/network-security-config"
  android:name="${applicationName}"
  android:icon="@mipmap/ic_launcher"
  android:label="f1">
  <activity
   android:name=".MainActivity"
   android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
   android:exported="true"
   android:hardwareAccelerated="true"
   android:launchMode="singleTop"
   android:theme="@style/LaunchTheme"
   android:windowSoftInputMode="adjustResize">
   <!-- Specifies an Android theme to apply to this Activity as soon as
        the Android process has started. This theme is visible to the user
        while the Flutter UI initializes. After that, this theme continues
        to determine the Window background behind the Flutter UI. -->
   <meta-data
    android:name="io.flutter.embedding.android.NormalTheme"
    android:resource="@style/NormalTheme" />
   <intent-filter>
    <action android:name="android.intent.action.MAIN" />
    <category android:name="android.intent.category.LAUNCHER" />
   </intent-filter>
  </activity>
  <!-- Don't delete the meta-data below.
       This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
  <meta-data
   android:name="flutterEmbedding"
   android:value="2" />
 </application>
</manifest>

主要.dart

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
 const MyApp({Key? key}) : super(key: key);

 @override
 Widget build(BuildContext context) {
  return MaterialApp(
   debugShowCheckedModeBanner: false,
   title: 'Name App',
   theme: ThemeData(
    primarySwatch: Colors.blue,
   ),
   home: Scaffold(
    appBar: AppBar(
     title: const Text('Name Page'),
    ),
    body: const SafeArea(
     child: MyHomePage(),
    ),
   ),
  );
 }
}

class MyHomePage extends StatefulWidget {
 const MyHomePage({Key? key}) : super(key: key);

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

class _MyHomePageState extends State<MyHomePage> {

 //работает, потому что https
 //final String _path = 'https://flutter.github.io/assets-for-api-docs/assets/widgets/owl-2.jpg';

 //не работает, потому что http
 final String _path = 'http://fr38060s.bget.ru/_html/perform/img/car.jpg';

 @override
 void initState() {
  super.initState();
 }

 @override
 void dispose() {
  super.dispose();
 }

 @override
 Widget build(BuildContext context) {
  return Align(
   alignment: Alignment.center,
   child: Image.network(
    _path,
    fit: BoxFit.contain,
    width: 300.0,
    height: 400.0,
   ),
  );
 }

}