My Android manifest is full of errors after updating to Android 3.0.0 [duplicate]

Answer 1

No need to disable AAPT2. :) In line 56 of your AndroidManifest.xml you define an activity:

<activity android:name="com.box.androidsdk.content.auth.OAuthActivity" />

The 'activity' tag can only be nested under the 'application' element. For more info please look at the Android Manifest structure documentation.

Answer 2

The Android docs mentioned about the migration guide here : https://developer.android.com/studio/build/gradle-plugin-3-0-0-migration.html

Element hierarchies in the Android manifest

In previous versions of AAPT, elements nested in incorrect nodes in the Android manifest are either ignored or result in a warning. For example, consider the following sample:

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
   package="com.example.myname.myapplication">
   <application
       ...
       <activity android:name=".MainActivity">
           <intent-filter>
               <action android:name="android.intent.action.MAIN" />
               <category android:name="android.intent.category.LAUNCHER" />
           </intent-filter>
           <action android:name="android.intent.action.CUSTOM" />
       </activity>
   </application>
</manifest>

Note that you must check your Manifest if you really comply to the specific nesting rule they provided otherwise your app wont compile.

Manifest file structure

The code snippet below shows the general structure of the manifest file and every element that it can contain. Each element, along with all of its attributes, is fully documented in a separate file.

<manifest>

    <uses-permission />
    <permission />
    <permission-tree />
    <permission-group />
    <instrumentation />
    <uses-sdk />
    <uses-configuration />  
    <uses-feature />  
    <supports-screens />  
    <compatible-screens />  
    <supports-gl-texture />  

    <application>

        <activity>
            <intent-filter>
                <action />
                <category />
                <data />
            </intent-filter>
            <meta-data />
        </activity>

        <activity-alias>
            <intent-filter> . . . </intent-filter>
            <meta-data />
        </activity-alias>

        <service>
            <intent-filter> . . . </intent-filter>
            <meta-data/>
        </service>

        <receiver>
            <intent-filter> . . . </intent-filter>
            <meta-data />
        </receiver>

        <provider>
            <grant-uri-permission />
            <meta-data />
            <path-permission />
        </provider>

        <uses-library />

    </application>

</manifest>

In your case you must transfer your

<activity android:name="com.box.androidsdk.content.auth.OAuthActivity" />

inside in <application> so that it will compile.

Disabling AAPT2 is just a workaround but not a real answer.