Как да предам споделени предпочитания от една дейност към друга дейност?

Имам две дейности в моя проект, едната дейност е MainActivity, а другата е Main2activity. В Main2activity приемам информация от потребителя и я съхранявам в SharedPreference. Сега искам да предам тези данни на MainActivity и да покажа тези данни на потребителя.

Кодът за Main2activity е

 package com.example.to_doapp;

import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.EditText;
import java.io.Serializable;
import java.util.ArrayList;
public class Main2Activity extends AppCompatActivity {




public void BackMain ( View view )
{
    Intent intent = new Intent( getApplicationContext() ,MainActivity.class ) ;
    SharedPreferences sharedPreferences = this.getSharedPreferences( "com.example.to_doapp;", Context.MODE_PRIVATE);
    EditText editText = ( EditText) findViewById( R.id.editText3) ;
    String s = editText.getText().toString();
    sharedPreferences.edit().putString("task" , s ) .apply();

    //intent.putStringArrayListExtra("key",arr);
    startActivity(intent);



}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main2);
    Toolbar toolbar = findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    FloatingActionButton fab = findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });
}

}

code foe Mainactivity е

package com.example.to_doapp;

import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;

import java.io.Serializable;
import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {


public void onclick (View view){

    Intent intent = new Intent(getApplicationContext(), Main2Activity.class );
    startActivity(intent);
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Toolbar toolbar = findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    FloatingActionButton fab = findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });

    Intent intent = getIntent();


 }

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}

}

Искам да знам как да предам sharedpreferences и как да покажа тези данни на потребителя в списък. Благодаря ви за помощта предварително.