What's the usage of tools:targetApi="m"?

Question

I have an app uses clearText between Android-client and server using Retrofit, and in Android 9+ it's not allowed to use clearText.

To ignore that I added android:usesCleartextTraffic="true" in Manifest but it warns: tools:ignore="GoogleAppIndexingWarning" and suggests to add tools:targetApi="m".

It's a bit confusing:

• Is the tools:targetApi="m" means that any attributes with tools: is for Marshmallow and higher?

• Is it for using this version of Manifest or something else? Is this making unwanted mistake in my app?

My Manifest:

... <application     android:name=".ApplicationClass"     android:allowBackup="true"     android:fullBackupContent="false"     android:hardwareAccelerated="true"     android:icon="@drawable/ic_launcher"     android:label="@string/app_name"     android:supportsRtl="false"     android:theme="@style/AppTheme.NoActionBar"     android:usesCleartextTraffic="true"     tools:ignore="GoogleAppIndexingWarning"     tools:targetApi="m">     ... 

Answer 1

From the docs you can read:

Indicates that Lint should treat this type as targeting a given API level, no matter what the project target is

This means it will affect only the annotated one.

Other attributes with tools won't be affected. tools is a namespace, from which you can get attributes, an attribute won't affect the entire namespace.