Xylophone - Using Flutter and Dart Packages to Speed Up Development

Guide to Using Flutter Packages

• Flutter and Dart allow developers to add packages and plugins into Flutter and Dart ecosystems.
• this benefit developers by building an app without the need to build apps from scratch.
• Existing packages enable many use cases—for example:
  • making network requests (http).
  • custom navigation/route handling (fluro).
  • integration with device APIs (url_launcher and battery).
  • using third-party platform SDKs like Firebase (FlutterFire).

What is the difference between a package and a plugin?

• A plugin is a type of package.
• plugin is shortend for plugin package.

Packages

• a Dart package is a directory containing a pubspec file.
• a package can contain dependencies (listed in the pubspec).
• Dart libraries, apps, resources, tests, images, and examples.
• The pub.dev site lists many packages—developed by Google engineers and Flutter and Dart community.
• I can use these packages in my application.

  Plugins

• A plugin package is type of package that makes platform functionality available to the app.
• Plugin packages can be written for Android, iOS, web, macOS, Windows, Linux, or any combination thereof.
• plugin might provide Flutter apps with the ability to use a device’s camera.

Using packages

some things to be done in order to use flutter package.

Searching for packages

• Packages are published to pub.dev.
• The Flutter landing page on pub.dev displays top packages that are compatible with Flutter.
• The Flutter Favorites page on pub.dev lists the plugins and packages that have been identified as packages should first consider using when writing Flutter app.
• browse the packages on pub.dev by filtering on Android plugins, iOS plugins, web plugins, or any combination thereof.

Adding a package dependency to an app

how To add the package, to an app?

1. Depend on it:
   • inside the pubspec.yaml file located inside the app folder, and add package under dependencies.
2. Install it:
   • From the terminal Run:

     flutter pub get
     

   • From Android Studio/IntelliJ: Click Packages get in the action ribbon at the top of pubspec.yaml.
   • From VS Code: Click Get Packages located in right side of the action ribbon at the top of pubspec.yaml.
3. Import it
   • Add a corresponding import statement in the Dart code.
4. Stop and restart the app, if necessary
   • If the package brings platform-specific code (Kotlin/Java for Android, Swift/Objective-C for iOS), code must be built into app.
   • Hot reload and hot restart only update the Dart code.
   • full restart of the app might be required to avoid errors like MissingPluginException when using the package.

Conflict resolution

• Suppose the app use package and another package and both depend on specific package but with different version.
• it causes a potential conflict.
• To avoid this is for package to use version ranges rather than specific versions when specifying dependencies.
• example of ranged:

  url_launcher: ^5.4.0    # Good, any version >= 5.4.0 but < 6.0.0