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Can you provide the below requested information to better understand the issue:

Steps to reproduce
Please provide a sample application or apk to reproduce the issue.
Also kindly mention the steps to be followed for reproducing the issue with the given sample application.

Expected output
Could you please explain the expected behavior.

Current output
Could you please explain the current behavior.

Here is a sample app

**Steps to reproduce**
- Try to compile the project and see the error in MainActivity.kt
- Edit build.gradle by not using the alpha version of KTX (use the current stable one) and see that it compiles

**Expected output**
The project compiles with newer versions of KTX

**Current output**
The project doesn't compile

ComponentActivity is part of androidx.activity and not androidx.core.

In this particular case, you're "mixing" alpha and stable releases. Change the appcompat dependency to this:

    implementation 'androidx.appcompat:appcompat:1.1.0-alpha02'

Project: platform/frameworks/support
Branch: androidx-master-dev

commit 48e9a199bb88dc3ea79043b541ff8a0ae174b09c
Author: Ian Lake <ilake@google.com>
Date:   Wed Jul 31 10:24:02 2019

    Restore @hide Core 1.1.0 binary compatibility
   
    Make androidx.core.app.ComponentActivity
    implement LifecycleOwner to maintain binary
    compatibility with Core 1.0.0.
   
    This fixes compatibility issues where devs
    could upgrade to Core 1.1.0 and not Fragment
    1.1.0 and have their FragmentActivity /
    AppCompatActivity no longer be considered
    a LifecycleOwner.
   
    This is essentially a revert to the changes to
    androidx.core.app.ComponentActivity from
    https://android-review.googlesource.com/743643
   
    Test: Ran in a sample app, tested with Fragments 1.0 and 1.1.0
    BUG: 126612680
    Change-Id: I10493f8138120cfa76255c0830a795e415fb1316

M       core/core/api/restricted_1.2.0-alpha03.txt
M       core/core/api/restricted_current.txt
M       core/core/src/main/java/androidx/core/app/ComponentActivity.java

https://android-review.googlesource.com/1094409
https://goto.google.com/android-sha1/48e9a199bb88dc3ea79043b541ff8a0ae174b09c

  The following changes were cherrypicked through Coastguard (https://android-build.googleplex.com/coastguard/)
  Release Track: (https://android-build.googleplex.com/coastguard/dashboard/6158886217056256/#/cherrypickHistory/all)
  Created: 2019-07-31 20:30:50.921789+00:00
  Changes: aosp/1094491
 

AndroidX follows semantic versioning and this extends to our restricted APIs in our artifacts as well (since they are, across artifacts, a defacto API surface). As such, we've decided to restore the underlying API surface that was driving AppCompat 1.0 so that you don't run into issues when using Core 1.1.0 and AppCompat 1.0 / Fragment 1.0.

This fix will be available in Core 1.1.0-rc03 and 1.2.0-alpha03.