Testable Android Architecture

So many testing tools exist for Android including JUnit, Mockito, Robolectric, and Espresso. But how can you design your application to leverage each one most effectively? This talk introduces a modified version of the Model View Presenter (MVP) architecture to organize your code to be more flexible, maintainable, and testable.

Transcript

1. Testable Android
   Architecture
   29 Sept 2016 / Chuck Greb
   

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2. Clean code
   Software Craftsmanship
   

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3. Art is anything you can do
   well. Anything you can do
   with Quality.
   “
   ”
   - Robert M. Pirsig
   

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5. Clean Architecture
   MVC <> MVP <> MVVM
   

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6. In the beginning
   

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7. Activity
   

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8. Activity
   Activity
   Lifecycle
   System
   Services
   

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9. Activity
   EditText
   Button
   Activity
   Lifecycle
   System
   Services
   

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10. Activity
    EditText
    Button
    Web
    Service
    Storage
    AsyncTask
    Activity
    Lifecycle
    System
    Services
    

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11. Fragment
    Activity
    EditText
    Button
    Web
    Service
    Storage
    AsyncTask
    Activity
    Lifecycle
    System
    Services
    Fragment
    Fragment
    Lifecycle
    

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12. Fragment
    Activity
    EditText
    Button
    Web
    Service
    Storage
    AsyncTask
    Activity
    Lifecycle
    System
    Services
    Fragment
    Fragment
    Lifecycle
    User
    Input
    Input
    Validation
    

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13. Fragment
    Activity
    Web
    Service
    Storage
    AsyncTask
    Activity
    Lifecycle
    System
    Services
    Fragment
    Fragment
    Lifecycle
    User
    Input
    setRetainInstance(true)
    EditText
    Button
    Input
    Validation
    

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14. Fragment
    Activity
    Web
    Service
    Storage
    AsyncTask
    Activity
    Lifecycle
    System
    Services
    Fragment
    Fragment
    Lifecycle
    User
    Input
    setRetainInstance(true)
    Intent
    Parcelable
    Extras
    EditText
    Button
    Input
    Validation
    

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15. Web
    Service
    Storage
    Activity
    Fragment
    Fragment
    AsyncTask
    setRetainInstance(true)
    Activity
    Lifecycle
    Fragment
    Lifecycle
    System
    Services
    User
    Input
    Intent
    ActivityInstrumentati
    onTestCase2
    Parcelable
    Extras
    EditText
    Button
    Input
    Validation
    

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17. There has to be a
    better way
    

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18. Activity Logic
    

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19. Activity Logic
    Data
    

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20. Activity Logic
    Data
    View
    

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21. View
    (Activity)
    Controller
    (Logic)
    Model
    (Data)
    View
    

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22. View
    (Activity)
    Presenter
    (Logic)
    Model
    (Data)
    View
    

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23. View
    (Activity)
    ViewModel
    (Logic)
    Model
    (Data)
    View
    

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24. Controller
    (Activity)
    Subcontroller
    (Logic)
    Model
    (Data)
    View
    

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25. - Phil Karlton
    There are two hard things in
    computer science: cache
    invalidation, naming things,
    [and errors off by one.]
    “
    ”
    

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26. Clean Architecture
    Model View
    Presenter Controller
    MVP(C)
    

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27. Controller
    (Activity)
    Presenter
    (Logic)
    Model
    (Data)
    View
    

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28. Activity Presenter
    (Logic)
    Model
    (Data)
    View
    Controller
    

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29. Web
    Service
    Storage
    Activity
    Activity
    Lifecycle
    System
    Services
    User
    Input
    Presenter
    View Model
    Controller
    Button
    EditText
    Thread
    Input
    Validation
    

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30. Web
    Service
    Storage
    Activity
    Activity
    Lifecycle
    System
    Services
    User
    Input
    Presenter
    View Model
    Controller
    Thread
    Button
    EditText
    Input
    Validation
    

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31. Mock
    Service
    Mock
    Storage
    Test
    Controller
    Presenter
    Model
    Controller
    Thread
    JUnit
    TestRunner
    

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32. A test is not a unit test if:
    → It talks to the database
    → It communicates across the network
    → It touches the file system
    → It can't run at the same time as any of
    your other unit tests
    → You have to do special things to your
    environment (such as editing config files)
    to run it.
    Michael Feathers, 2005
    A Set of Unit Test Rules
    

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33. Mock
    Service
    Mock
    Storage
    Test
    Controller
    Presenter
    Model
    Controller
    Thread
    JUnit
    TestRunner
    

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34. Activity
    Robolectric
    TestRunner
    Robolectric
    Runtime
    Environment
    Simulated
    Input
    Stub
    Presenter
    View
    Button
    EditText
    Input
    Validation
    

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35. Demo App
    https://github.com/ecgreb/mvpc
    

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36. Eraser Map
    

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38. Start where you are
    

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