由于某种随机原因，我的应用程序在 android 工作室中不断崩溃

Question

so basically, i am trying to develop an app in android studio but it keeps crashing. I got no idea why. can som1 help?

This is the error code below:

2022-07-24 12:45:13.430 9938-9938/com.example.aviationista E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.aviationista, PID: 9938
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.aviationista/com.example.aviationista.MainActivity}: java.lang.InstantiationException: java.lang.Class<com.example.aviationista.MainActivity> cannot be instantiated
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3545)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3792)
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:103)
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2210)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loopOnce(Looper.java:201)
    at android.os.Looper.loop(Looper.java:288)
    at android.app.ActivityThread.main(ActivityThread.java:7839)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
 Caused by: java.lang.InstantiationException: java.lang.Class<com.example.aviationista.MainActivity> cannot be instantiated
    at java.lang.Class.newInstance(Native Method)
    at android.app.AppComponentFactory.instantiateActivity(AppComponentFactory.java:95)
    at androidx.core.app.CoreComponentFactory.instantiateActivity(CoreComponentFactory.java:45)
    at android.app.Instrumentation.newActivity(Instrumentation.java:1273)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3532)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3792) 
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:103) 
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2210) 
    at android.os.Handler.dispatchMessage(Handler.java:106) 
    at android.os.Looper.loopOnce(Looper.java:201) 
    at android.os.Looper.loop(Looper.java:288) 
    at android.app.ActivityThread.main(ActivityThread.java:7839) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003) 

Answer 1

Make sure the Activity is placed inside the Manifest file. Look here

Answer 2

Open the app>manifests. You'll find a File called AndroidManifest

in between

<application
.
.<activity
            android:name="com.example.<your_package_name>.ComponentInfo" />
.
>
</application>

This might have happened because you created a class and created a layout file seperately.. hemceforth create it like so right clock New> Activity > Empty Activity

That way your layout files get created and the manifest entry gets added as well automatically