Hello again 👋🏼

In this PR, I worked on products cache policy.

Products cache policy:

our cache policy is simply "remove products from the cache after x time interval"

so when we insert the product into the cache we also save the current time to shared preference to check the expiration of cache late on.

  Future<Iterable<int>> insertProducts(List<Product> products) async {
    final SharedPreferences sharedPreferences =
        await SharedPreferences.getInstance();
    sharedPreferences.setInt(
        cacheTimeKey, DateTime.now().millisecondsSinceEpoch);
    return productsBox.addAll(products);
  }

and when we retrieve the products from the cache, first of all, we check the expiration of the cache, and if the cache is expired we delete all the cache.

  Future<List<Product>> getProductsByGroupId(int groupId) async {
    final bool isCacheExpired = await _isCacheExpired();
    if (isCacheExpired) {
      await productsBox.deleteFromDisk();
      return <Product>[];
    } else {
      return productsBox.values
          .where((Product product) => product.groupId == groupId)
          .toList();
    }
  }

For more details please check the code changes section.

issues to solve:

• product image caching.

Somethings to improve:

• improve UI code.
• write some unit tests for HomeLocalDataSource functionality and HomeRepository.
• try to merge my work on PR #11 with @MohammedAlimoor PR #26, or delete unused files from #11 PR.

Description

Please include a summary of the change and which issue is fixed and List any dependencies that are required for this change..

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• [ ] Bug fix
• [x] New feature

Checklist:

• [ ] I have performed a self-review of my own code.
• [ ] My changes generate no new warnings on the project.

Hello & Welcome to my first PR 👋🏼

based on this diagram that I draw (feel free if you think there are a better approach to perform this future )

I believe first we need to implement product loader class remote and local In this PR I worked on remote products loader.

I'm new to the flutter framework, I'm coming from iOS World so I think there are a lot of improvements we can apply to the code especially test code.

What next

1- improve this PR Code. 2- work on local products loader. 3- create a new loader class that tries to get data from the internet first and on a fail case try to get data from the cache.

maybe the code will be something like this

class FallBackProductLoader extends ProductsLoader {
  final ProductsLoader remoteLoader;
  final ProductsLoader localLoader;

  FallBackProductLoader(this.remoteLoader, this.localLoader);

  @override
  Future<List<Product>> loadProducts() {
    try {
      return remoteLoader.loadProducts();
    } catch (error) {
      return localLoader.loadProducts();
    }
  }
}

This commit try to redesign the structure of define the Getx Controller on Home Controller to be in code style of builder to use the controller later with OBX and builder in easier way.

In other hand , later in any other page you can define the controller without put and use the style like this commit way , or you can find the controller in this code structure with Get.find instead of HomeController() definition.

Login Feature

Description

Work on login Feature

The interesting part of the above diagram is LoginUseCaseOutputComposer Any Object interest about login result needed to implement or extend the LoginUseCaseOutput

In our case, we have three components interested in login result

• LoginController (change state of UI based on login result)
• AuthManager (save the login result to the device cache)
• LoginRouter (navigate to the home screen, or show an error message)

all of these classes implement the LoginUseCaseOutput.

and compose all of them using LoginUseCaseOutputComposer which is already implement the LoginUseCaseOutput

finally, we pass LoginUseCaseOutputComposer to LoginUseCase so all these Objects will know about the login result.

    final LoginUseCase useCase = LoginUseCase(
      loginService: loginService,
      output: LoginUseCaseOutputComposer(<LoginUseCaseOutput>[
        loginController,
        authManager,
        loginRouter,
      ]),
    );

Login results will be sent in the same order we compose the LoginUseCaseOutputComposer outputs, on our case and as the above code shows:

• to the LoginController to update the UI state.
• to the AuthManager to save the token on the success case.
• finally to the LoginRouter to show the error message or navigate to the home screen.

and we have a test to verify this behavior

  test('makeUseCase should compose correct outputs with correct order',
      () async {
    SharedPreferences.setMockInitialValues(<String, String>{});

    final SharedPreferences sharedPreferences =
        await SharedPreferences.getInstance();

    final LoginService loginService = DummyLoginService();
    final LoginController loginController = LoginController();
    final LoginRouter loginRouter = LoginRouter(NavigatorFactorySpy());
    final AuthManager authManager = AuthManager(sharedPreferences);

    final LoginUseCaseFactory sut = LoginUseCaseFactory();
    final LoginUseCase useCase = sut.makeUseCase(
      authManager: authManager,
      loginRouter: loginRouter,
      loginController: loginController,
      loginService: loginService,
    );

    final LoginUseCaseOutput output = useCase.output;

    expect(output, isInstanceOf<LoginUseCaseOutputComposer>());

    final LoginUseCaseOutputComposer outputComposer =
        output as LoginUseCaseOutputComposer;
    expect(outputComposer.outputs.length, 3);
    expect(outputComposer.outputs[0], isInstanceOf<LoginController>());
    expect(outputComposer.outputs[1], isInstanceOf<AuthManager>());
    expect(outputComposer.outputs[2], isInstanceOf<LoginRouter>());
  });

so in the future, if we need to add a Logger or Event tracker to LoginUseCase:

class Logger extends LoginUseCaseOutput {

  @override
  void onLoginSuccess(LoginResult result) {
      // perform logger work
  }

  @override
  void onLoginFail(LoginErrors error) {
     // perform logger work
  }
}

add logger to LoginUseCaseOutputComposer

    final LoginUseCase useCase = LoginUseCase(
      loginService: loginService,
      output: LoginUseCaseOutputComposer(<LoginUseCaseOutput>[
        loginController,
        authManager,
        loginRouter,
       logger,
      ]),
    );

it's too easy 🚀

any suggestions? 🧐

Items to work on:

• improve login UI
• create a new view for web login
• currently, the login router always navigates to mobile home UI, we need a generic way to make the NavigatorFactory decide the correct route based on the platform we run the app on (web or mobile).

Fixes #42

Type of change

• [ ] New feature

Checklist:

• [x] I have performed a self-review of my own code.
• [x] My changes generate no new warnings on the project.

Issue Requirements The user can filter items based on their category.

API Documentation Check the GET METHOD Get Product Categories and check category field in Products repository. Endpoint: /api/v2/product-categories

Mobile Design

Tablet and Web Design

Description

Please include a summary of the change and which issue is fixed and List any dependencies that are required for this change..

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• [ ] Bug fix
• [ ] New feature

Checklist:

• [ ] I have performed a self-review of my own code.
• [ ] My changes generate no new warnings on the project.

Description

Working on mobile UI.

1- We have a different screen for mobile, web common widgets like key_pad.

2- create routes for web and mobile

3- check the platform and return the correct route

final String initial = kIsWeb ? WebRoutes.SPLASH : MobileRoutes.HOME;

final List<GetPage<Widget>> routes = kIsWeb ? webRoutes : mobileRoutes;

any suggestions?

Fixes #17

Type of change

• [ ] New feature

Checklist:

• [x] I have performed a self-review of my own code.
• [x] My changes generate no new warnings on the project.

Although The-POS-Flutter seems amazing and definitely one would wish to contribute to this project but there is no documentation in the readme file about setting up a working copy of this project in one's local machine for testing and development.

It would be a lot helpful if you please provide detailed step by step instructions about how to setup a working copy of this project on local machine.

Description

Please include a summary of the change and which issue is fixed and List any dependencies that are required for this change..

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• [ ] Bug fix
• [ ] New feature

Checklist:

• [ ] I have performed a self-review of my own code.
• [ ] My changes generate no new warnings on the project.

Issue Requirements The user can create a new customer for the invoice

API Documentation Check the POST METHOD Create New Customer. Endpoint: /api/v2/costumers

This Exception sometimes show after launching the app

=================================================================================================
[VERBOSE-2:ui_dart_state.cc(209)] Unhandled Exception: HiveError: Box has already been closed.
#0      BoxBaseImpl.checkOpen (package:hive/src/box/box_base_impl.dart:76:7)
#1      BoxImpl._writeFrames (package:hive/src/box/box_impl.dart:83:5)
#2      BoxImpl.putAll (package:hive/src/box/box_impl.dart:67:12)
#3      BoxBaseImpl.addAll (package:hive/src/box/box_base_impl.dart:122:11)
#4      HomeLocalDataSource.insertProducts (package:thepos/features/home/data/datasources/home_local_data_source.dart:21:24)
#5      HomeRepository.getProducts (package:thepos/features/home/data/repositories/home_repository.dart:28:23)
<asynchronous suspension>
#6      HomeController.getProduct (package:thepos/features/home/presentation/controllers/home_controller.dart:59:31)
<asynchronous suspension>

This Exception show after launching the app on mobile ui

======== Exception caught by widgets library =======================================================
The following assertion was thrown while applying parent data.:
Incorrect use of ParentDataWidget.

The ParentDataWidget Expanded(flex: 1) wants to apply ParentData of type FlexParentData to a RenderObject, which has been set up to accept ParentData of incompatible type ParentData.

Usually, this means that the Expanded widget has the wrong ancestor RenderObjectWidget. Typically, Expanded widgets are placed directly inside Flex widgets.
The offending Expanded is currently placed inside a RepaintBoundary widget.

The ownership chain for the RenderObject that received the incompatible parent data was:
  Center ← Expanded ← RepaintBoundary ← IndexedSemantics ← NotificationListener<KeepAliveNotification> ← KeepAlive ← AutomaticKeepAlive ← KeyedSubtree ← SliverList ← Viewport ← ⋯
When the exception was thrown, this was the stack: 
#0      RenderObjectElement._updateParentData.<anonymous closure> (package:flutter/src/widgets/framework.dart:5835:11)
#1      RenderObjectElement._updateParentData (package:flutter/src/widgets/framework.dart:5851:6)
#2      RenderObjectElement.attachRenderObject (package:flutter/src/widgets/framework.dart:5873:7)
#3      RenderObjectElement.mount (package:flutter/src/widgets/framework.dart:5544:5)
#4      SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:6194:11)
...     Normal element mounting (7 frames)
#11     Element.inflateWidget (package:flutter/src/widgets/framework.dart:3673:14)
#12     Element.updateChild (package:flutter/src/widgets/framework.dart:3422:20)
#13     SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#14     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#15     SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#16     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#17     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#18     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#19     StatelessElement.update (package:flutter/src/widgets/framework.dart:4746:5)
#20     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#21     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#22     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#23     ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#24     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#25     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#26     StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#27     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#28     StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#29     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#30     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#31     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#32     StatelessElement.update (package:flutter/src/widgets/framework.dart:4746:5)
#33     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#34     SliverMultiBoxAdaptorElement.updateChild (package:flutter/src/widgets/sliver.dart:1242:37)
#35     SliverMultiBoxAdaptorElement.performRebuild.processElement (package:flutter/src/widgets/sliver.dart:1147:35)
#36     Iterable.forEach (dart:core/iterable.dart:279:35)
#37     SliverMultiBoxAdaptorElement.performRebuild (package:flutter/src/widgets/sliver.dart:1191:24)
#38     SliverMultiBoxAdaptorElement.update (package:flutter/src/widgets/sliver.dart:1125:7)
#39     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#40     RenderObjectElement.updateChildren (package:flutter/src/widgets/framework.dart:5700:32)
#41     MultiChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6356:17)
#42     _ViewportElement.update (package:flutter/src/widgets/viewport.dart:228:11)
#43     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#44     SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#45     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#46     SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#47     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#48     SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#49     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#50     SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#51     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#52     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#53     StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#54     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#55     StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#56     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#57     SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#58     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#59     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#60     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#61     ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#62     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#63     SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#64     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#65     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#66     StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#67     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#68     StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#69     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#70     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#71     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#72     ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#73     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#74     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#75     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#76     StatelessElement.update (package:flutter/src/widgets/framework.dart:4746:5)
#77     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#78     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#79     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#80     StatelessElement.update (package:flutter/src/widgets/framework.dart:4746:5)
#81     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#82     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#83     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#84     ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#85     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#86     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#87     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#88     ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#89     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#90     RenderObjectElement.updateChildren (package:flutter/src/widgets/framework.dart:5700:32)
#91     MultiChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6356:17)
#92     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#93     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#94     StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#95     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#96     StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#97     Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#98     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#99     Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#100    ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#101    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#102    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#103    StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#104    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#105    StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#106    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#107    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#108    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#109    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#110    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#111    StatelessElement.update (package:flutter/src/widgets/framework.dart:4746:5)
#112    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#113    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:6202:14)
#114    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#115    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#116    StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#117    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#118    StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#119    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#120    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#121    StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#122    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#123    StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#124    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#125    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#126    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#127    ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#128    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#129    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#130    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#131    StatelessElement.update (package:flutter/src/widgets/framework.dart:4746:5)
#132    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#133    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#134    StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#135    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#136    StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#137    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#138    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#139    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#140    ProxyElement.update (package:flutter/src/widgets/framework.dart:5020:5)
#141    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#142    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#143    StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#144    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#145    StatefulElement.update (package:flutter/src/widgets/framework.dart:4872:5)
#146    Element.updateChild (package:flutter/src/widgets/framework.dart:3412:15)
#147    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4690:16)
#148    StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#149    Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#150    BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2620:33)
#151    WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:882:21)
#152    SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1143:15)
#153    SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1080:9)
(elided 3 frames from dart:async)