title: the application launch collapses via android studio
body: <p>i am new to the community so please be patient. this is the logcat:</p>
  <p>E/AndroidRuntime: FATAL EXCEPTION: main
  Process: com.example.linebet, PID: 7546
  java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.linebet/com.example.linebet.Register}: java.lang.InstantiationException: java.lang.Class&lt;com.example.linebet.Register&gt; cannot be instantiated
  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3365)
  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601)
  at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
  at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
  at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066)
  at android.os.Handler.dispatchMessage(Handler.java:106)
  at android.os.Looper.loop(Looper.java:223)
  at android.app.ActivityThread.main(ActivityThread.java:7656)
  at java.lang.reflect.Method.invoke(Native Method)
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
  Caused by: java.lang.InstantiationException: java.lang.Class&lt;com.example.linebet.Register&gt; 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:1253)
  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3353)
  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601) 
  at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85) 
  at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
  at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066) 
  at android.os.Handler.dispatchMessage(Handler.java:106) 
  at android.os.Looper.loop(Looper.java:223) 
  at android.app.ActivityThread.main(ActivityThread.java:7656) 
  at java.lang.reflect.Method.invoke(Native Method) 
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592) 
  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947) </p>