pubspec use dependencies

Your pubspec.yaml file is like your project's recipe book. It lists all the external packages (libraries) your app needs to work.

How to Add Packages

Import Libraries

You can add libraries from different places. You might have a library in another folder on your computer (local path) or one hosted online, like on GitHub (remote repository).

Here’s how you'd list them:

dependencies:
  transmogrify:
    path: ../
  otherlib:
    git:
      url: https://github.com/awesomeplugin.git
      ref: main

Understand Carret Syntax

When you add a package from pub.dev, you'll often see a little ^ symbol before the version number, like ^1.0.0. This is called the Carret syntax.

What does ^1.0.0 mean?

It tells your project that it can use any version of the package that is backward compatible with version 1.0.0. This usually means any version from 1.0.0 up to (but not including) 2.0.0.

dependencies:
  flutter:
    sdk: flutter
  cupertino_icons: ^1.0.0

This is the same as >=1.0.0 <2.0.0.

Handling Version Issues

Dependency Overrides

Sometimes, different packages in your project might need different versions of the same underlying library. This can cause conflicts. Dependency overrides let you tell your project exactly which version of a library to use, no matter what other packages ask for.

This helps avoid problems when multiple parts of your app rely on the same thing but expect different versions. You are temporarily forcing all references to use a specific version.

name: my_app
dependencies:
  transmogrify: 3.2.1
  otherlib: ^1.0.2
dependency_overrides:
  transmogrify: 3.2.1

In this example, even if otherlib normally uses transmogrify version 2.0.0, the dependency_overrides makes sure the project uses version 3.2.1 for transmogrify everywhere.