Android 应用程序无法发送 http 请求

Question

我有一个 android 应用程序，它使用 Retrofit 发出 http 请求 (POST) 并进一步评估传入数据。我的应用程序在我的测试 phone (Samsung J5 P) 中运行得非常好，它可以正常连接和发送请求。但是在尝试在两个不同的 phone 上同时操作该应用程序时，另一个 phone 上的应用程序以某种方式无法发送请求（连接失败时改造调用 onFailure 方法）。我已经启用了所有权限，但问题似乎发生了。

此外，我在桌面 (localhost) 上托管了服务器，并确保我的两台设备都连接到同一网络。

是什么导致了这个问题？谢谢

Answer 1

在 res/xml 目录中创建网络配置文件

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

然后在清单的应用程序标签中添加 android:networkSecurityConfig="@xml/network_security_config"

Answer 2

从 Android 9（API 级别 28）开始，默认禁用明文支持。

也看看 - https://koz.io/android-m-and-the-war-on-cleartext-traffic/

Codelab 说明 - https://codelabs.developers.google.com/codelabs/android-network-security-config/index.html

Option 1 -

First try hitting the URL with "https://" instead of "http://"

Option 2 -

Create file res/xml/network_security_config.xml -

<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
    <domain-config cleartextTrafficPermitted="true">
        <domain includeSubdomains="true">api.example.com(to be adjusted)</domain>
    </domain-config>
</network-security-config>
AndroidManifest.xml -

<?xml version="1.0" encoding="utf-8"?>
<manifest ...>
    <uses-permission android:name="android.permission.INTERNET" />
    <application
        ...
        android:networkSecurityConfig="@xml/network_security_config"
        ...>
        ...
    </application>
</manifest>
Option 3 -

android:usesCleartextTraffic Doc

AndroidManifest.xml -

<?xml version="1.0" encoding="utf-8"?>
<manifest ...>
    <uses-permission android:name="android.permission.INTERNET" />
    <application
        ...
        android:usesCleartextTraffic="true"
        ...>
        ...
    </application>
</manifest>

 android:targetSandboxVersion can be a problem too -

According to Manifest Docs -

android:targetSandboxVersion

The target sandbox for this app to use. The higher the sandbox version number, the higher the level of security. Its default value is 1; you can also set it to 2. Setting this attribute to 2 switches the app to a different SELinux sandbox. The following restrictions apply to a level 2 sandbox:

The default value of usesCleartextTraffic in the Network Security Config is false.
Uid sharing is not permitted.
So Option 4 -

If you have android:targetSandboxVersion in <manifest> then reduce it to 1

AndroidManifest.xml -

<?xml version="1.0" encoding="utf-8"?>
<manifest android:targetSandboxVersion="1">
    <uses-permission android:name="android.permission.INTERNET" />
    ...
</manifest>

Android 应用程序无法发送 http 请求

Android application unable to send http requests

java

android

httprequest

retrofit

retrofit2