5. Scrollable Widgets

Written by Vincent Ngo

Building scrollable content is an essential part of UI development. There’s only so much information a user can process at a time, let alone fit on an entire screen in the palm of your hand!

In this chapter, you’ll learn everything you need to know about scrollable widgets. In particular, you’ll learn:

• How to use ListView.
• How to nest scroll views.

You’ll continue to build the Yummy app by adding HomeScreen, a new view that enables users to explore different restaurants, food categories, and view friends’ posts.

By the end of this chapter, you’ll be a scrollable widget wizard!

Getting Started

Open the starter project in Android Studio, then run flutter pub get if necessary and run the app.

You’ll see a placeholder for each tab as shown below:

Project Files

There are new files in this starter project to help you out. Before you learn how to create scrollable widgets, take a look at them.

Assets Folder

The assets directory contains all the images that you’ll use to build your app.

Sample Images

• categories: Contains images for food categories.
• food: Contains sample food items from a restaurant menu.
• profile_pics: Contains Kodeco team member pictures.
• restaurants: Contains restaurant hero images.

New Classes

In the lib directory, you’ll also notice the new api folder, as shown below:

API Folder

The api folder contains a mock service class.

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Introducing ListView

ListView is a very popular Flutter component. It’s a linear scrollable widget that arranges its children linearly and supports horizontal and vertical scrolling.

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Introducing Constructors

A ListView has four constructors:

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Setting Up the Explore Screen

The first screen you’ll create is the ExploreScreen. It contains three sections:

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