ndroid 8: Cleartext HTTP traffic not permitted

According to Network security configuration –

Starting with Android 9 (API level 28), cleartext support is disabled by default.

Also have a look at Android M and the war on cleartext traffic

Codelabs explanation from Google

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>

Also as @david.s’ answer pointed out 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>