Flutter and Dart Cookbook

Chapter 4. Handling Lists and Maps

In this chapter, the fundamentals of data handling with Dart are outlined. The aim of this chapter is to cover Lists and Maps that are used to provide foundational data structures for information handling in Dart.

If you are lucky enough to be familiar with other languages, then many of the concepts presented should be familiar. However, in case this is your first time seeing these techniques, the example pieces of code are self-contained. You may find it helpful to run and experiment with the examples to gain a feel of the workings of the language.

The chapter begins by discussing Lists, which are indexable data structures used to hold objects. Lists are very common elements in Dart, as they can be used in a variety of scenarios.

We also discuss how to use Maps, which are useful for handling key/value pairs. A key/value pair is an associative relationship where the key is used as an index to access a value. For example, you may have a months of the year data structure in which the key is a number and the value is derived from the number, e.g., 1 generates the month January and 12 denotes December.

Over the course of this chapter, you will learn how to utilize Maps and Lists within your application.

4.1 Creating Lists of Data

Problem

You want a way to use a list of values within a Dart application.

Solution

Use a List to organize objects as an ordered collection. A List represents an array object that can hold information. It provides a simple ...