简单的方法

添加usesCleartextTraffic到AndroidManifest.xml

<application
...
android:usesCleartextTraffic="true"
...>

指示应用程序是否打算使用明文网络流量，例如明文HTTP。API级别为27或更低的应用程序的默认值为“true”。API级别为28或更高的应用程序默认为“false”。

简单的方法

添加usesCleartextTraffic到AndroidManifest.xml

<application
...
android:usesCleartextTraffic="true"
...>

指示应用程序是否打算使用明文网络流量，例如明文HTTP。API级别为27或更低的应用程序的默认值为“true”。API级别为28或更高的应用程序默认为“false”。

You may check if you are sending clearText through HTTP Fix : https://medium.com/@son.rommer/fix-cleartext-traffic-error-in-android-9-pie-2f4e9e2235e6 OR In the Case of Apache HTTP client deprecation (From Google ) : With Android 6.0, we removed support for the Apache HTTP client. Beginning with Android 9, that library is removed from the bootclasspath and is not available to apps by default. To continue using the Apache HTTP client, apps that target Android 9 and above can add the following to their AndroidManifest.xml:

源 https://developer.android.com/about/versions/pie/android-9.0-changes-28

对于在调试中运行的React Native应用程序，将@Xenolion提到的xml块添加到位于<project>/android/app/src/debug/res/xml中的react_native_config.xml中

类似于下面的代码片段:

<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
    <domain-config cleartextTrafficPermitted="true">
        <domain includeSubdomains="false">localhost</domain>
        <domain includeSubdomains="false">10.0.2.2</domain>
        <domain includeSubdomains="false">10.0.3.2</domain>
    </domain-config>
    <base-config cleartextTrafficPermitted="true">
        <trust-anchors>
            <certificates src="system" />
        </trust-anchors>
    </base-config>
</network-security-config>

只需在AndroidManifest.xml文件的应用程序标签中设置usesCleartextTraffic标志。 不需要为Android创建配置文件。

 <application
   android:usesCleartextTraffic="true"
   .
   .
   .>

完全工作的解决方案，无论是Android或react原生用户面对这个问题，只需添加这个 android: usesCleartextTraffic = " true " 在AndroidManifest.xml文件中像这样:

android:usesCleartextTraffic="true"
tools:ignore="GoogleAppIndexingWarning">
<uses-library
    android:name="org.apache.http.legacy"
    android:required="false" />

在<application>..</application>标签:

<application
      android:name=".MainApplication"
      android:label="@string/app_name"
      android:icon="@mipmap/ic_launcher"
      android:allowBackup="false"
      android:theme="@style/AppTheme"
        android:usesCleartextTraffic="true"
        tools:ignore="GoogleAppIndexingWarning">
        <uses-library
            android:name="org.apache.http.legacy"
            android:required="false" />
      <activity
        android:name=".MainActivity"
        android:label="@string/app_name"/>
 </application>