Must use 2.0
Must use 2.0 about app:--- package com.socialMedia.mustuse ; import androidx.appcompat.app.AppCompatActivity ; import android.content.Intent ; import android.os.Bundle ; import android.view.View ; public class aboutblock extends AppCompatActivity { @Override protected void onCreate (Bundle savedInstanceState) { super .onCreate(savedInstanceState) ; setContentView(R.layout. activity_aboutblock ) ; } public void privicy (View view) { startActivity( new Intent( this, Privacy_Policy. class )) ; } } <? xml version ="1.0" encoding ="utf-8" ?> <ScrollView xmlns: android ="http://schemas.android.com/apk/res/android" xmlns: app ="http://schemas.android.com/apk/res-auto" xmlns: tools ="http://schemas.android.com/tools" android :layout_width ="match_parent" android :layout_height ="match_parent" tools :context =".aboutblock" > <RelativeLay...