Activity Navigation One Activity to another Activity

Main Activity :-

 <?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.edimaudo.activitynavigation.MainActivity">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Main Activity"
        android:id="@+id/MainActivityButton"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true" />
</RelativeLayout>

Second Activity :- 

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.edimaudo.activitynavigation.secondActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textView"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true"
        android:textSize="30dp" />
</RelativeLayout>



Java MainActivity :-

package com.edimaudo.activitynavigation;

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

public class MainActivity extends AppCompatActivity {

    Button myButton;

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

        myButton = (Button) findViewById(R.id.MainActivityButton);
        myButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent in = new Intent(MainActivity.this,secondActivity.class);
                in.putExtra("activityOne","first Activity data");
                startActivity(in);
            }
        });
    }
}



Java Secound Activity :-

package com.edimaudo.activitynavigation;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.TextView;

public class secondActivity extends AppCompatActivity {
    private TextView textView;

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

        textView = (TextView) findViewById(R.id.textView);
        Bundle extra = getIntent().getExtras();
        textView.setText("");
        if (extra != null){
            String myString = extra.getString("activityOne");
            textView.setText(myString);
        }

    }
}