MobX Architecture

Hello! This package allows you to more easily and cleanly bind your MobX stores to your UI. For now, it focuses mainly on the binding of ViewModels to the UI, and provides an instance of MediaQueryData, for sizing widgets, getting the orientation, etc. more conveniently. ( No one wants MediaQueries scattered all over the place, now do they? )

If you do like this package, please do star it over on GitHub. Any and all contributions, whether they be to the docs, or the code, in the form of bug fixes or new features or even feature requests, are all highly, highly appreciated and encouraged.

This package has a lot of potential, and I plan to actively maintain this package and add new features on as regular a basis as possible, and contributions would really help out a lot. So, any new feature you feel will benefit this package, please don't hesitate to add a feature request over on the package's repository.

Getting Started

First, let's get some of the introductions, assumptions, and requirements out of the way.

This package helps implement a custom version of the MVVM architecture pattern, smooshing together the Widget-Store-Service organization pattern mentioned in the Flutter MobX docs with the traditional Model-View-ViewModel architecture pattern, resulting in a unified pattern where:

  • The Model is relatively unchanged, and houses the services, API calls etc.
  • The ViewModel is unified with the MobX Store, and has the dual purpose of managing state (either local, shared or any other) as well as the business logic of the corresponding View
  • The View is relatively unchanged, with the one major difference being Observer widgets sprinkled about as necessary, wrapping the parts of the UI that render based on the state of the app

This package assumes the following:

  • You are using the MVVM architecture pattern to architect your app
  • You are using Provider to inject your MobX stores. ( Although not required per se, as the package has widgets for that scenario, it is still highly recommended ).

This package depends on / must be used in conjunction with the following extra packages:

  • MobX (Of course)
  • Flutter Mobx (For Observer Widgets, which you most likely are using already)

Note:

  • Provider is highly recommended to be used alongside MobX itself, as well as this package, and is internally used by parts of the package as well,to inject your MobX stores wherever they are required. Checkout the MobX docs for more info.
  • Using the parts of the package that depend on Provider ( .usesProvider constructors) without actually having Provider as a dependency may lead to unexpected behaviour

Before we begin, here are some packages that I recommend using with this package, some because they play better than others with this package, and some because I feel they promote the safest, cleanest code:

  • Get_it for a service locator ( Even though Provider is most likely a dependency already, this package comes in handy for
    injecting services and such, and also for accessing them from ViewModels, where the BuildContext isn't as readily available, if at all
  • Hive for local data persistence

This package exposes 4 widgets, and 6 total variations in the implementation across those 4 widgets ( using constructors ), with
the widgets and their variations being split based on these 3 requirements:

  • Binding a ViewModel that is not a MobX Store
  • Binding a ViewModel that is a MobX Store
  • Stateless and Stateful vairations of the above mentioned criteria, so as to be able to
    access widget lifecycle methods, such as inItState( ) and dispose( ) , when required.

The widgets are therefore as follows:

  • StatefulVMStoreBuilder<T>( ) : This widget is used for when you need to access widget lifecycle methods, and are binding a ViewModel that is also a MobX Store to the UI. It has two constructors:

    • StatefulVMStoreBuilder<T>.usesProvider( ) : This constructor is used if you are using the Provider package. It automatically reads the appropriate store from the type T , using Provider.

            StatefulVMStoreBuilder<Store>.usesProvider(  
              key: ///Optionally provide a key ,  
              builder: (BuildContext context, T store, SizingInfo sizingInfo) {  
              /// Provides the store, the BuildContext and an object containing  
              /// the sizing information of the screen, accessible through. 
              /// [sizingInfo.height] and [sizingInfo.width]  
      
              return Widget();
              },  
              initState: (store) {
              ///Provide a optional ininState method
              },  
              dispose: (store) {
              ///Provide a optional dispose method
              },  
            );		
      
    • StatefulVMStoreBuilder<T>.standAlone( ) : This constructor is used if you are not using the Provider package

                StatefulVMStoreBuilder<Store>.standAlone(  
                  key: ///Optionally provide a key , 
                  viewModelStoreBuilder: () => MyViewModelStore(),   
                  builder: (BuildContext context, T store, SizingInfo sizingInfo) {  
                    /// Provides the store, the BuildContext and an object containing  
                    /// the sizing information of the screen, accessible through. 
                    /// [sizingInfo.height] and [sizingInfo.width]  
      
                    return Widget();
                    },  
                  initState: (store) {
                  ///Provide a optional ininState method
                  },  
                  dispose: (store) {
                  ///Provide a optional dispose method
                  },  
                );
      

      Note: If you are using this constructor, then Observer Widgets from the Flutter Mobx package or equivalent reactions should be used, and setState or other ways of re-triggering the build function of the widget must not be used, as the Store is instantiated inside the build method, and re-triggering it causes a new store to be created.

      This of course does not occur with the .usesProvder variation of the widget, as then the instance of the store is gotten from Provider.

      Furthermore, if you instantiate the store with values that are stored/kept track of elsewhere in your code, or if you are fine with the store’s instance members returning to their default values when the build function is called again, then re-triggering the build function is perfectly fine.

  • StatelessVMStoreBuilder<T>( ): This widget is used for when you don't need to access widget lifecycle methods, and are binding a ViewModel that is also a MobX Store to the UI. It has two constructors:

    • StatelessVMStoreBuilder<T>.usesProvider( ) : This constructor is used if you are using the Provider package. It automatically reads the appropriate store from the type T , using Provider.

             StatelessVMStoreBuilder<Store>.usesProvider(  
               key: ///Optionally provide a key , 
               builder: (BuildContext context, T store, SizingInfo sizingInfo) {
               /// Provides the store, the BuildContext and an object containing  
               /// the sizing information of the screen, accessible through 
               /// [sizingInfo.height] and [sizingInfo.width]
      
               return  Widget();
               },
             );
      
    • StatelesslVMStoreBuilder<T>.standAlone( ) : This constructor is used if you are not using the Provider package

            StatelessVMStoreBuilder<Store>.standAlone(  
              key: ///Optionally provide a key , 
              viewModelStoreBuilder: () => MyViewModelStore(),  
              builder: (BuildContext context, T store, SizingInfo sizingInfo) {
              /// Provides the store, the BuildContext and an object containing  
              /// the sizing information of the screen, accessible through 
              /// [sizingInfo.height] and [sizingInfo.width]
      
              return  Widget();
              },
            );
      

      Note: If you are using this constructor, then Observer Widgets from the Flutter Mobx package or equivalent reactions should be used, and setState or other ways of re-triggering the build function of the widget must not be used, as the Store is instantiated inside the build method, and re-triggering it causes a new store to be created.

      This of course does not occur with the .usesProvder variation of the widget, as then the instance of the store is gotten from Provider.

      Furthermore, if you instantiate the store with values that are stored/kept track of elsewhere in your code, or if you are fine with the store’s instance members returning to their default values when the build function is called again, then re-triggering the build function is perfectly fine.

  • StatefulVMBuilder<T>( ) : This widget is used for when you need to access widget lifecycle methods, and are binding a ViewModel that is not a MobX Store to the UI.

        StatefulVMBuilder<Object>(  
          key: ///Optionally provide a key , 
          viewModelStoreBuilder: () => MyViewModel(),  
          builder: (BuildContext context, T viewModel, SizingInfo sizingInfo) {
          /// Provides the ViewModel, the BuildContext and an object containing  
          /// the sizing information of the screen, accessible through 
          /// [sizingInfo.height] and [sizingInfo.width]
    
          return  Widget();
          },
          initState: (store) {
          ///Provide a optional ininState method
          },  
          dispose: (store) {
          ///Provide a optional dispose method
          }, 
        );
    
  • StatelessVMBuilder<T>( ) : This widget is used for when you don't need to access widget lifecycle methods, and are binding a ViewModel that is not a MobX Store to the UI.

          StatelessVMBuilder<Object>(  
            key: ///Optionally provide a key , 
            viewModelStoreBuilder: () => MyViewModel(),  
            builder: (BuildContext context, T viewModel, SizingInfo sizingInfo) {
            /// Provides the ViewModel, the BuildContext and an object containing  
            /// the sizing information of the screen, accessible through 
            /// [sizingInfo.height] and [sizingInfo.width]
    
            return  Widget();
            },
          );
    

    The package has been designed with modularity as one of its core principles. Except for MVVM, MobX itself, and Provider, which nearly 100% of people use alongside MobX, the package enforces no additional packages or principles, from Dialog services to data persistence, all the way to how you should structure your app, it's all left to the developer to implement in any way they please.

This stems from a core belief that every project is different, and has a different set of requirements and a rigorous structure and certain way to do things may only ever result in benefiting a small percentage of those projects, if that, and will likely result in many scenarios where people might have to "fight the framework", so to speak.
As such, going forward, this is probably the only thing about this framework that will be set in stone.

The framework will always therefore be lightweight, unobstructive, unobtrusive, and, most importantly, modular, and will prioritize the above criteria above all else, allowing developers to switch out (or add on top off) functionality provided by the framework (or add new functionality all together) in the form of either separate, purpose-built packages or custom solutions, as easily as is possible.


License

This package is licensed under the Apache License, Version 2.0

Copyright 2021 Tanzil Zubair Bin Zaman  
  
Licensed under the Apache License, Version 2.0 (the "License");  
you may not use this file except in compliance with the License.  
You may obtain a copy of the License at  
  
 http://www.apache.org/licenses/LICENSE-2.0  
Unless required by applicable law or agreed to in writing, software  
distributed under the License is distributed on an "AS IS" BASIS,  
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  
See the License for the specific language governing permissions and  
limitations under the License.  

Libraries

mobx_architecture