Grid layout (LazyVGrid, LazyHGrid) in iOS Swift - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is LazyVGrid in SwiftUI?

LazyVGrid is a SwiftUI view that arranges child views in a vertical grid. It loads views only when needed, improving performance for large data sets.

beginner

How does LazyHGrid differ from LazyVGrid?

LazyHGrid arranges child views in a horizontal grid, loading views lazily as they appear on screen, unlike LazyVGrid which arranges vertically.

intermediate

What is the role of GridItem in LazyVGrid or LazyHGrid?

GridItem defines the size and spacing of each column (in LazyVGrid) or row (in LazyHGrid). You can specify fixed, flexible, or adaptive sizes.

intermediate

Why use lazy grids instead of regular grids in SwiftUI?

Lazy grids load views only when they appear on screen, saving memory and improving performance, especially with many items.

beginner

How do you make a grid with 3 equal columns using LazyVGrid?

Create an array of three GridItems with .flexible() size and pass it to LazyVGrid's columns parameter.

Which SwiftUI view arranges items in a vertical grid and loads views lazily?

A VStack

B LazyVGrid

C LazyHGrid

D HStack

LazyVGrid arranges items vertically and loads views lazily for better performance.

What does a GridItem with .fixed(100) size mean?

A The grid item is exactly 100 points wide or tall

B The grid item can grow or shrink flexibly

C The grid item adapts to available space

D The grid item is hidden

A fixed GridItem has a constant size of 100 points.

Which grid type arranges items horizontally in SwiftUI?

A LazyHGrid

B ZStack

C GridStack

D LazyVGrid

LazyHGrid arranges items horizontally.

Why is lazy loading important in grids?

A It changes colors automatically

B It loads all views at once

C It disables scrolling

D It improves performance by loading views only when needed

Lazy loading improves performance by creating views only when they appear on screen.

How do you specify spacing between columns in LazyVGrid?

A Using padding on each item

B Using frame modifiers

C Using the spacing parameter in LazyVGrid initializer

D Spacing is not customizable

LazyVGrid has a spacing parameter to set space between columns.

Explain how to create a simple 2-column vertical grid using LazyVGrid in SwiftUI.

Think about how you define columns and place views inside LazyVGrid.

Describe the benefits of using LazyHGrid over a regular horizontal stack for many items.

Consider what happens when you have many items off screen.