IncorrectOperationException: Sorry but parent: Android (app) has already been disposed (see the cause for stacktrace) so the child: com.android.tools.idea.res.AssetRepositoryImpl@3340a8f2 will never be disposed

package com.example.android.ablo;

 import android.content.Intent;
 import android.graphics.Color;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
 import android.widget.Button;
import android.widget.TextView;

public class Start extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_start);

    final TextView welcome = (TextView) findViewById(R.id.tvwelcome);
    welcome.setText("Welcome to ABLO!");
    welcome.setTextColor(Color.parseColor("#FFFFFF"));
    final TextView start = (TextView) findViewById(R.id.tvstart);
    start.setText("Helps you to monitor and block overuse of phone by your employees");
    start.setTextColor(Color.parseColor("#FFFFFF"));
    final Button bstart = (Button) findViewById(R.id.bstart);

    bstart.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent i = new Intent(Start.this, LoginActivity.class);
            Start.this.startActivity(i);
        }
    });
}
}

package com.example.android.ablo;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class LoginActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_login);

    final Button bregister = (Button) findViewById(R.id.bregister);

    bregister.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent i = new Intent(LoginActivity.this, RegisterActivity.class);
            LoginActivity.this.startActivity(i);
        }
    });


}
}