How to resolve the error Cannot access 'androidx.core.app.ComponentActivity'

Question

I was working on a project a couple days ago, which was saved and closed, only to get an error in the MainActivity, when I opened it today.

Error: Cannot access 'androidx.core.app.ComponentActivity' which is a supertype of 'com.careerinfluencer.fivehundreddays.MainActivity'. Check your module classpath for missing or conflicting dependencies

I don't even know the module classpath to check nor what to include here..

But I'm just going to add some of the AndroidManifest file.

AndroidManifest :

<application
    ...
    <activity
        android:name=".MainActivity"
        android:exported="true"
        android:label="@string/app_name"
        android:theme="@style/Theme.FiveHundredDays">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

Here's an image of this error :

I just noticed I get an error in the AndroidManifest file also. At .MainActivity in activity to be precise.

error: MainActivity must extend android.app.Activity

Here's an image of this error :

I would really appreciate and welcome any Idea on how to fix this.

Thanks in Advance for your help.

Answer 1

Finaly fixed it..

Base on my research, I think because my internet connection was off-line. Gradle couldn't reach the library, it thought that was missing.

To Fix it I simply went; File -> Sync Project with Gradle Files

You could also try; File -> Invalidate Cache & Restart

Answer 2

i haven't imported androidx activity package, it might help you

implementation "androidx.activity:activity-ktx:1.7.1"