How to find elements in List in Flutter

Introduction

In Flutter/Dart, there are situations when we need to find elements in a List. In this post, we'll look at how to do it.

How to find elements in List in Flutter

In Flutter/Dart we have several methods that allow us to find element/elements in a List.

Using contains() method to check if a list contains an element or not

var list = [0, 1, 2, 3];
print(list.contains(2)); // true
print(list.contains(4)); // false

The output:

true
false

Using theindexOf() method to find the index of the first occurrence of an element

var list = [0, 1, 2, 3];
print(list.indexOf(2)); // 2

The output:

2

Using lastIndexOf() method to find the index of last occurence of an element

var list = [0, 1, 2, 3, 2, 1, 0];
print(list.lastIndexOf(0));  // 6

The output:

6

Using theindexWhere() method to find the index of the first element that matches a specific condition

var list = [0, 1, 2, 3, 2, 1, 0];
print(list.indexWhere((item) => item > 1));  // 2

The output:

2

Using thelastIndexWhere() method to find the index of the last element that matches given condition

var list = [0, 1, 2, 3, 2, 1, 0];
print(list.lastIndexWhere((item) => item > 1));  // 4

The output:

4

Conclusion

In this article, we presented several ways to find element/elements in a list in Flutter/Dart.

Check more valuable articles about Lists in Flutter:

• Filter items in a List in Flutter/Dart
• Sort a List in Flutter/Dart
• FlatMap a list of lists in Flutter/Dart
• Reverse a List in Flutter/Dart
• Iterate over List in Flutter/Dart
• Remove items from a List in Flutter/Dart
• Access items from List in Flutter/Dart
• Create a list in Flutter/Dart
• Combine Lists in Flutter/Dart