Moxy

Moxy 2 is out! Check out the migration guide and give it a try!

Moxy is a library that allows for hassle-free implementation of the MVP pattern in an Android Application. Without troubles of lifecycle and boilerplate code!

Illustration of how Moxy is working: schematic_using

Capabilities

Moxy has a few killer features:

Presenter stays alive when Activity is being recreated (it simplifies multithread handling)
Automatical restoration of all content in the recreated Activity (including additional dynamic content)

Example

View interface

interface MainView : MvpView {

    @AddToEndSingle
    fun displayUser(user: User)
}

class MainActivity : MvpAppCompatActivity(R.layout.activity_main), MainView {

    private val presenter by moxyPresenter { MainPresenter() }

    override fun displayUser(user: User) {
        userLayout.showUser(user)
    }
}

Presenter

class MainPresenter : MvpPresenter<MainView>() {
    override fun onFirstViewAttach() {
        viewState.showUser(getCurrentUser())
    }
}

Inject with Dagger2

Kotlin:

@Inject
lateinit var presenterProvider: Provider<MainPresenter>

private val presenter by moxyPresenter { presenterProvider.get() }

Java:

@InjectPresenter
MainPresenter presenter;

@Inject
Provider<MainPresenter> presenterProvider;

@ProvidePresenter
MainPresenter providePresenter() {
    return presenterProvider.get();
}

Android studio and Intellij templates

We will change this template in future In order to avoid tedious task of writing boilerplate code for binding activities, fragments and its presentation parts, we recommend use of Android Studio templates for Moxy.

Links

Telegram channels from original moxy community

Telegram channel (en)
Telegram channel (ru)

Integration

(Please replace moxyVersion with the latest version number:

Base library:

implementation "com.github.moxy-community:moxy:$moxyVersion"

Java project

annotationProcessor "com.github.moxy-community:moxy-compiler:$moxyVersion"

Kotlin

apply plugin: 'kotlin-kapt'

kapt "com.github.moxy-community:moxy-compiler:$moxyVersion"

Default android module

For additional base view classes MvpActivity and MvpFragment add this:

implementation "com.github.moxy-community:moxy-android:$moxyVersion"

AppCompat module

If you are using AppCompat, you’ll need MvpAppCompatActivity and MvpAppCompatFragment classes. Add this:

implementation "com.github.moxy-community:moxy-app-compat:$moxyVersion"

AndroidX module

If you’re using AndroidX, you’ll need a different implementation for MvpAppCompatActivity and MvpAppCompatFragment classes. Use this one:

implementation "com.github.moxy-community:moxy-androidx:$moxyVersion"

AndroidX (Google material) module

If you’re using Google material, use MvpBottomSheetDialogFragment and add this:

implementation "com.github.moxy-community:moxy-material:$moxyVersion"

Kotlin extensions

Declare presenters in your views using property delegate:

class MyFragment: MvpFragment() {
    ...
    private val presenter by moxyPresenter { presenterProvider.get() }
    ...
}

Launch coroutines in presenter scope:

class MyPresenter : MvpPresenter<MvpView>() {
    override fun onFirstViewAttach() {
        presenterScope.launch {
            // Coroutine that will be canceled when presenter is destroyed
        }
    }
}

To use MvpDelegateHolder.moxyPresenter and MvpPresenter.presenterScope, add this:

implementation "com.github.moxy-community:moxy-ktx:$moxyVersion"

New Features and Compiler option for Migration from old version

By default, each MvpView method must have an annotation @StateStrategyType. In the version 1 of Moxy it was allowed to omit stategies for methods. In this case a default strategy was applied.

You can fallback to the old behavior. To do this, set the disableEmptyStrategyCheck parameter to true.

disableEmptyStrategyCheck : ‘true’

In this case the default strategy will be AddToEndSingleStrategy. In the old version the default strategy was AddToEndStrategy.

To change default strategy provide for the defaultMoxyStrategy parameter a full class name of the new default strategy.

defaultMoxyStrategy : 'moxy.viewstate.strategy.OneExecutionStateStrategy'

If the compiler finds MvpView method without the @StateStrategyType annotation, it’d show an error via standard method for notifying about compilation problems. For ease of migration from older versions we have provided an additional mechanism: EmptyStrategyHelper. It collects all the errors associated with an empty strategy in one place. Using it, you can easily navigate from the EmptyStrategyHelper directly to the method with a missing strategy.

To switch the error output method enable this option

enableEmptyStrategyHelper : 'true'

How to correctly use compilation flags check out the sample-app build.gradle file

ProGuard\R8

moxy-android, moxy-appcompat, moxy-androidx and moxy-material artifacts already include ProGuard rule files, no additional configuration required. While using standalone moxy you have to manually add rules from this file.

Road Map

[✓] ~~Provide a migration tool from com.arello-mobile.moxy and its default strategy~~
[✓] ~~Kotlin incremental compilation support~~
[✓] ~~Remove reflectors and common presenter store~~
[✓] ~~Add delivery module support~~
[х] ~~Add separate Annotation Processor for migration~~
[✓] ~~Research possibility of removing @InjectViewState annotation~~
Provide Runtime Implementation

Moxy Community

Brave people who created the library:

@senneco
@jordan1997
@xanderblinov
@asitnkova
@alaershov
@bejibx
@katkoff
@ekursakov
@SavinMike
@sychyow
@AlexeyKorshun
@dmdevgo
@rsajob
@terrakok
@mohaxspb
@CherryPerry
@fl1pflops
@phoenixxt
@Dosssik
@AcoustickSan
@seven332
@v-grishechko
@sbogolepov
@A-Zaiats
@lion4ik
@NotPerfectBlue
@IlyaGulya

You may also find them in contributors page of the old project

Contributing

Install code style to your IntelliJ or Android Studio. MoxyAndroid.xml For import file use or Mac OS: Preferences -> Editor -> Code style -> Scheme -> Import Scheme -> IntelliJ IDEA code style XML -> choose the MoxyAndroid.xml file in finder

License

The MIT License (MIT)

Copyright (c) 2019 Moxy Community

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.