Gain insights into Dart's object-oriented features, explore extensions, enums, mixins, and asynchronous programming. Discover hands-on code practice to confidently apply Dart in your projects.

dart.tar.gz

dart2_7

Dart is a fully object-oriented, class-based, simple, and clean language. Google’s popular mobile framework, Flutter uses Dart language to implement high-quality native applications, so it’s recommended that you understand Flutter before beginning this course.

In this course, you will dive deep into Dart 2 language features while using interactive hands-on code playgrounds. This course will help you become confident with Dart extensions, enums, mixins, generics, libraries, asynchronous programming, class variables, callable classes, and generator functions.

By the end of this course, you will have a strong understanding of Dart principles, and you’ll be ready to start using this powerful language in your own projects.

Developing Web Applications with Dart

Let's check out the type safe implementations for two of the Dart's [collection literals](https://dart.dev/guides/language/language-tour#using-collection-literals): Set & Map.

# Set

In a [Set](https://api.dart.dev/stable/2.8.4/dart-core/Set-class.html) collection, each object can only occur once.

## Creating Set
A set `theSet` of the `String` data type is constructed using the parameterized constructor `Set<String>.from({"1"})`.

```dart
Set<String> theSet = Set<String>.from({"1"});
```

## Same data type item

Two more items of the same type `String` are added to the set `theSet`, iterating over the set `theSet`, and printing all items in the set.

```dart
void main() {
  Set<String> theSet = Set<String>.from({"1"});
  theSet.add("2");
  theSet.add("3");

  print("Printing items in Dart Set");
  //iterate over set and print all items
  for (String item in theSet) {
    print(item);
  }
}
```

**Output:**

```notepad
Printing items in Dart Set
1
2
3

```

## Different data type item

Adding a different data type `int` will throw a compile-time error.

```dart
void main() {
  Set<String> theSet = Set<String>.from({"1"});

  //Adding int data type will throw compile time error
  theSet.add(3);
}
```

**Output:**

The compile-time error is due to adding `int` data instead of `String` data.

```notepad
main.dart:7:14: Error: The argument type 'int' can't be assigned to the parameter type 'String'.
  theSet.add(3);
```

In this lesson, you will learn to use generics for two more Dart's collections: Set and Map.

Introduction

Dart Extensions

Dart Enums

Dart Mixins

Dart Generics

Dart Libraries

Asynchronous Programming In Dart

Miscellaneous

Next Steps

Generic Collections- Set & Map

Set

Creating Set