SharedPreferences / DataStore in Android Kotlin - UI Render Trace

Component - SharedPreferences / DataStore

This UI component demonstrates how to save and read simple user data using SharedPreferences or DataStore in Android Kotlin. It shows a text input and a button to save the input, and a text display to show the saved value.

Widget Tree

LinearLayout
├─ EditText
├─ Button
└─ TextView

The root is a vertical LinearLayout containing three children stacked vertically: an EditText for user input, a Button to save the input, and a TextView to display the saved data.

Render Trace - 4 Steps

Step 1: LinearLayout

Step 2: EditText

Step 3: Button

Step 4: TextView

State Change - Re-render

Trigger:User types text and presses the Save button

Before

TextView shows 'Saved value will appear here', no data saved

→

After

TextView updates to show the text user typed and saved

Re-renders:The TextView updates to display the new saved value; EditText and Button remain unchanged

UI Quiz - 3 Questions

What happens when the user presses the Save button?

A The app closes immediately

B The typed text is saved and displayed below

C The EditText clears and nothing is saved

D The button disappears

Key Insight

Using SharedPreferences or DataStore allows apps to save small pieces of user data persistently. The UI typically includes input fields and buttons to save data, and text views to show saved values. Keeping the layout simple and clear helps users understand how to save and see their data.