Goal

• Solve ‘Cleartext HTTP traffic to X.X.X not permitted’ error

Problem

• I replaced the target SDK 27 with 28(Pie 9.0)
• After that, when trying to communicate with server by HTTP protocol, this error occured

Solution

Cause

• From API level 28(Pie 9.0) it has been default to prevent unencrypted HTTP protocl

AndroidDeveloper

1. Add a Network Security Configuration file

• The Network Security Configuration feature uses an XML file where you specify the settings for your app

1.1 Add xml file in res/xml

• Create network_security_config.xml file in src/res/xml directory

1.2. Add options

• Recommend to allow only specific domains

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<?xml version="1.0" encoding="utf-8"?> <network-security-config> <!-- Allow specific domains --> <domain-config cleartextTrafficPermitted="true"> <domain includeSubdomains="true">iot.qubics.kr</domain> </domain-config> <!-- Allow all domains --> <!-- <base-config cleartextTrafficPermitted="true" /> --> </network-security-config>

1.3. Edit AndroidManifest.xml

• Add android:networkSecurityConfig=”@xml/network_security_config” option

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<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="io.dorbae.android"> <application android:networkSecurityConfig="@xml/network_security_config" ...> .... </application> </manifest>

2. Edit only AndroidManiofest.xml

• Add android:useCleartextTraffic=”true” option

div style=”background: #eeeedd; overflow:auto;width:auto;border:solid gray;border-width:.1em .1em .1em .8em;padding:.2em .6em;”><table><tr><td><pre style="margin: 0; line-height: 125%">1 2 3 4 5 6 7 8 9</pre></td><td><pre style="margin: 0; line-height: 125%"><?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="io.dorbae.android"> <application android:usesCleartextTraffic="true" …> …. </application> </manifest> </pre></td></tr></table></div>

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References

• AndroidDeveloper NetworkSecurityPolicy
• StackOverflow
• 박상권의 삽질블로그