List with ForEach in iOS Swift - UI Render Trace

Component - List with ForEach

This UI component shows a vertical list of items using ForEach inside a List. Each item is displayed as a text row. It is like a grocery list where each item is shown one below the other.

Widget Tree

List
└── ForEach
    └── Text

The root is a List that creates a scrollable vertical list. Inside it, ForEach loops over data items. Each item is shown as a Text view in a row.

Render Trace - 3 Steps

Step 1: List

Step 2: ForEach

Step 3: Text

State Change - Re-render

Trigger:Data array changes (e.g., item added or removed)

Before

List shows original items

→

After

List updates to show new items reflecting the changed array

Re-renders:ForEach and its Text children re-render to match updated data

UI Quiz - 3 Questions

What does the ForEach do inside the List?

A It makes the List scroll horizontally

B It creates one Text row for each item in the data array

C It adds buttons to each row

D It changes the font size of the Text

Key Insight

Using List with ForEach is a simple way to show many items in a scrollable list. ForEach loops over your data and creates a UI row for each item. When your data changes, the list updates automatically, making dynamic lists easy to build.