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

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>

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>

我遇到了同样的问题，我注意到我的安全配置有不同的标签，就像@Xenolion的答案说

<network-security-config>
    <domain-config cleartextTrafficPermitted="true">
        <domain includeSubdomains="true">localhost</domain>
    </domain-config>
</network-security-config>

所以我把标签“domain-config”改为“base-config”，就像这样:

<network-security-config>
    <base-config cleartextTrafficPermitted="true">
        <domain includeSubdomains="true">localhost</domain>
    </base-config>
</network-security-config>

这对我很有效，

将此XML文件添加到: andriod / app / src / main / res / xml / network_security_config.xml

network_security_config.xml

xml/network_security_config.xml
<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
    <base-config cleartextTrafficPermitted="true">
        <trust-anchors>
            <certificates src="system" />
        </trust-anchors>
    </base-config>
    <domain-config cleartextTrafficPermitted="true">
        <domain includeSubdomains="true">your_domain1</domain>
    </domain-config>
    <domain-config cleartextTrafficPermitted="true">
        <domain includeSubdomains="true">your_domain2</domain>
    </domain-config>
</network-security-config>

然后将此代码添加到AndroidMenifest.xml

<application
    ...
      android:usesCleartextTraffic="true"
      android:networkSecurityConfig="@xml/network_security_config"
    ...
      >
      <!-- for http support-->
      <uses-library android:name="org.apache.http.legacy" android:required="false"/>
      ...
</application>
        

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