Note: This branch contains code for flavors, to use boilerplate without flavors checkout to withoutFlavors branch.

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Boilerplate with Flavors

• assets  

  • It will be located at "project/assets"

  • This folder will keep all the local resources that we will use in our application. It can further contain subcategories like "fonts", "images" etc having the corresponding folders.

• To make use of the contents of this folder we need to define it in pubspec.yaml.
  

• lib

  • It will be located at "project/lib"

  • This is the most important folder in a flutter project, everything that we code will sit here in most cases, if we are not using any platform-specific or native coding in our flutter application.

  • "Here we will not have a main.dart file. We will have a folder named flavors, we will look into it in more detail in coming steps."

• This boilerplate will contain following subcategories in lib folder:

  • constants

  • controllers

  • i18n

  • models

  • router

  • store

  • theme

  • utils

  • viewmodel

  • views

  • flavors

Let us understand one by one what each folder is going to do:

• Constants 

• This folder will contain all the constants that we will be using in our application.

• It can be subcategorized into categories like api constants, string constants, message constants, enums etc.

• Controllers

  • This folder will contain the code for all the network calls, in simpler language we can call it the "Network Layer" of our project.

  • Essentially, it will contain a base api class which contains the generic method for all kind of requests i.e. GET, POST, PUT, DELETE, PATCH, in this project we are using Dio for making API calls.

• i18n 

  • This folder will contain json for using localization in the project.

  • It can contain a json file for every language that we'll be using in the project.

• Models

  • This folder will contain the parsing models of every json object that we receive after a successful/unsuccessful API request. 

  • It will contain a generic response class that will be used in the base API class we discussed earlier.

  • Note: While making a response/request model make sure to remove the methods that are not in use, like toJson(), fromJson() etc.

• Router

  • This folder will contain our router class, that has all the navigation logic written as per Navigation 2.0 (route named navigation).

• Store

  • This folder will have any files or folders containing code for any local storage that we might use in our application.

  • It can have files for SQLite, Shared preferences, secure storage, hive database etc.

• Theme

  • This folder will contain files for colors, themes, textstyles etc that will be used in the project.

• Utils

  • Utils folder will have folders like various helper functions, validation functions etc.

  • Helper functions can have any general function that we can use in the entire application.

  • Validation functions will contain validation logic for text inputs etc.

• Viewmodels

  • This folder will contain mostly all the business logic that will be used in the application.

  • We are using Provider for state management in the given boilerplate.

  • This will contain a generic viewmodel, which will have common functions or attributes like state variables, update UI methods etc for all the viewmodels.

  • All the viewmodels that we make will be extension of the BaseViewModel in order to use the common functions.

• Views

  • This folder will contain the UI element of the application. 

  • This will further be categorized into screens and widgets.

  • Screen folder will contain the distinct screen UI.

  • Widgets folder will contain common UI elements that will be used in the entire application or entire module of the project.

• flavors

  • While using flavors, we will make use of this folder.

  • It will contain one main_common.dart file that will have the code with MaterialApp, it is the main entry point of our project, but it won't have runApp() method called in here.

  • Now comes the interesting part, each flavor will have its own file, say prod environment will have a file main_prod.dart and here runApp() will be called by passing the class that we created in main_common.dart.

Handling Flavors

Running application while using flavors

• Using command

  • Simple flutter run won't work out in the case of flavors. We will need to call the following command to run our app. 

  • flutter run --flavor flavor_name -t corresponding_main_flavor_file_path

  • E.g. flutter run --flavor qa -t lib/flavors/main_qa.dart

• Via VS Code

  • In this boilerplate launch.json file has been configured with three flavors, prod, dev and qa.

  • So in the located section there will be option to choose from any flavor, as shown below

• Creating Build via command

  • Simple flutter build apk won't work out in case of flavors. We will need to call the following command to build an android apk. 

  • flutter build apk --release --flavor flavor_name -t corresponding_main_flavor_file_path or

  • flutter build apk --release --obfuscate --split-debug-info=build/app/outputs/symbols --flavor flavor_name -t corresponding_main_flavor_file_path

  • E.g. flutter build apk --release --flavor qa -t lib/flavors/main_qa.dart or

  • flutter build apk --release --obfuscate --split-debug-info=build/app/outputs/symbols --flavor qa -t lib/flavors/main_qa.dart

• Adding/deleting flavors

  • Android

    • Just add/remove the object for your flavor in android/app/build.gradle as follows,
      

  • VS Code

    • Just add / remove the flavor object from .vscode/launch.json as follows:

• iOS

  • Adding or removing flavors from iOS will take a few setup, let's see how we can add a new flavor or edit the existing one for iOS.

  • Open XCode for your project > Product > Scheme > Manage Scheme

-  This will show all the existing flavors that we are using this boilerplate, we can delete any flavor from here if not required by clicking on "-" and can add a new one by clicking on "+".

  -   While adding a new flavor from here, make sure to select the target as "Runner" only.

  -   Once the scheme (flavor) is added we will need to make a few more changes.

  -   Go to Project Runner > Info & add debug, profile and release as per the name of the scheme. E.g. Debug-flavorname, Profile-flavorname & Release-flavorname.

  -   Go to Target Runner > Build Setting & change the display name of app as per different flavors, if required.

  -   Open XCode for your project > Product > Scheme > Edit Scheme and add the respective configuration file for the flavor.