Shared Preferences - Kotlin

To save your data

Main Activity code:

class MainActivity : AppCompatActivity() {


    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        var editor=getSharedPreferences("button_key",MODE_PRIVATE).edit()

        button_switch.setOnClickListener {
            //saving data
            editor.putBoolean("button_status",button_switch.isChecked)
            editor.apply()

            //retrieving data
            var prefs=getSharedPreferences("button_key",MODE_PRIVATE)
            val button_status_textview=prefs.getBoolean("button_status",false)
            textView_status.text="button status is $button_status_textview"
        }


    }

}

Here is the xml Code:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/textView_status"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Switch
        android:id="@+id/button_switch"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="32dp"
        android:layout_marginEnd="32dp"
        android:text="Switch"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

demo : you can retrieve  your data from different activity