Source Code of MainAcivity.java

Sharedpreferences sharedpreferences;
String mypreference;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main2);
    Button save = (Button) findViewById(R.id.save1);
    Button display = (Button) findViewById(R.id.display1);
    final EditText et1 = (EditText) findViewById(R.id.txtname1);
    sharedpreferences = getSharedPreferences(mypreference, Context.MODE_PRIVATE);

    save.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {

            String n = et1.getText().toString();
            SharedPreferences.Editor editor = sharedpreferences.edit();
            editor.putString(uname, n);
            editor.commit();
            Toast.makeText(getBaseContext(), "Data is saved successfully!",
                    Toast.LENGTH_SHORT).show();


        }
    });
    display.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {

            sharedpreferences = getSharedPreferences(mypreference,Context.MODE_PRIVATE);

            if (sharedpreferences.contains(uname)) {

                String t = sharedpreferences.getString(uname,"");
                Toast.makeText(getBaseContext(), "Data is \n"+t,Toast.LENGTH_SHORT).show();
            }
            else
            {
                Toast.makeText(getBaseContext(), "No Content Found",
                        Toast.LENGTH_SHORT).show();
            }
        }
    });
}

Source Code of activity_main.xml

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


<ScrollView xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_height="match_parent" android:layout_width="match_parent"
    xmlns:android="http://schemas.android.com/apk/res/android">
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        tools:context=".MainActivity">

        <TextView
            android:id="@+id/textView1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Enter Username"
            android:textAlignment="center"
            android:textAppearance="@style/TextAppearance.AppCompat.Body2"
            android:layout_marginTop="20dp"
            android:textSize="25sp"
            android:textColor="@android:color/holo_blue_light" />

        <EditText
            android:id="@+id/txtname1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="20"
            android:hint="Enter Name"
            android:layout_marginLeft="40dp"
            android:layout_marginRight="40dp"
            android:layout_marginTop="10dp"
            android:inputType="textPersonName"
            />

        <Button
            android:id="@+id/save1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="40dp"
            android:layout_marginTop="40dp"
            android:layout_marginRight="40dp"
            android:layout_marginBottom="10dp"
            android:background="@color/colorAccent"
            android:text="SAVE"
            android:textColor="@android:color/white"
            android:textSize="25sp" />
        <Button
            android:id="@+id/display1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="40dp"
            android:layout_marginTop="10dp"
            android:layout_marginRight="40dp"
            android:layout_marginBottom="70dp"
            android:background="@color/colorAccent"
            android:text="DISPLAY"
            android:textColor="@android:color/white"
            android:textSize="25sp" />
        <TextView
            android:id="@+id/textView2"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Developed By : w3techblog.com"
            android:textAlignment="center"
            android:textAppearance="@style/TextAppearance.AppCompat.Body2"
            android:layout_marginTop="20dp"
            android:textSize="25sp"
            android:textColor="@android:color/holo_blue_light" />
    </LinearLayout>
</ScrollView>

​

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