Ask for permission when "Next" button is clicked

LaunchActivity.java

public class LaunchActivity extends AppCompatActivity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    ...
        
    findViewById(R.id.next_btn).setOnClickListener(new View.OnClickListener() {
      @Override
        public void onClick(View v) {
          ActivityCompat.requestPermissions(LaunchActivity.this,
            new String[]{Manifest.permission.RECEIVE_SMS},
            REQUEST_CODE_READ_SMS);
        }
    });
  }
  
  ...
  
}