How to Write Clean Code in Android

Transcript

1. android Clean Code
   Mohanraj Karatadipalayam
   @kmmraj
   

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2. Let's Start With Unit Testing
   • Typical Activity Class
   • Data retrieval
   • Data manipulation and decoration
   • UI-specific activities like rendering,
   painting, responding to user events, and
   the creation of fragments.
   • One class does all work
   • Massive Activity, Massive Fragment,
   Massive ViewController
   

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3. Can I Test them ?
   • Lets take data retrieval
   • All methods are intertwined
   • Doing everything everywhere
   • I need API provider
   • I need SQLite
   • I need to convert from datamodel
   to viewmodel
   • Mocking cannot rescue
   

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4. Does your App Architecture supports unit
   testing ?
   • Search for the testing tools
   • Forgetting the need
   

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5. Where to start ?
   • Clean architecture
   • VIPER
   • Force fitting in to Android
   • clean-swift
   

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6. Android Clean Code
   

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7. Lets spilt the Monolithic Activity
   • Retrieve the data
   • Modify the model data
   according to viewmodel
   needs
   • Handle UI specific work
   • How they talk to each
   other ?
   • Interfaces
   • Unidirectional Flow
   

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8. Activity
   

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9. Activity Unit Testing
   • Using Roboletric to
   simulate the Activity
   • Canary test
   • How do we test the
   Activity without
   Interactor?
   

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10. Activity Unit Testing
    

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11. Activity Unit Testing
    

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12. Interactor
    • Interactor
    retrieves the
    data from
    data sources
    like the local
    DB, web
    service, and
    content
    provider.
    

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13. Why we need Worker ?
    • If the task is simpler- No
    need
    • If you foresee that the
    task can be reused
    somewhere else in the
    app, move it to the
    Worker.
    

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14. Testing Interactor
    • How to test
    Interactor
    with out
    Worker &
    Presenter
    

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15. Testing Interactor
    

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16. Presenter
    • Reduce the Model to VM
    

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17. Presenter
    

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18. Testing Presenter
    • FIRST
    • Fast
    • Isolated
    • Repeatable
    • Self-Validating
    • Timely
    

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19. Router
    • Determines the next
    screen
    • Pass the needed data to
    the next screen
    

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20. Testing Router
    

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21. Configurator
    

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22. Scaffolding
    

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23. What’s next?
    • Predictability
    • Developers can work across the technologies
    • Contribute
    • Refine
    

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