Implementing MVVM in Android - GDG Live

🔊 Wajahat Karim delivers a talk about implementing MVVM architecture in Android at an online webinar organized by GDG Live Pakistan.

👉 Full video: https://www.facebook.com/GDGLivePakistan/videos/224745351961006

Transcript

1. Implementing MVVM
   in Android
   Wajahat Karim
   GDE in Android
   wajahatkarim.com
   GDG Live Pakistan
   

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2. - Google Developer Expert in Android
   - Over 8 years experience in Android
   - Open Source Contributor
   - Technical Blogs & Books Writer
   - Love to share my knowledge with others
   Follow me on Twitter @WajahatKarim |
   wajahatkarim.com
   This is Wajahat Karim
   

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3. MV* - The Confusion Begins!
   Model
   Controller
   Presenter
   ViewModel
   Intent
   View
   

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4. Model-View-ViewModel (MVVM)
   Model ViewModel View
   This is a architecture not the architecture
   Exposes Data
   Requests Data
   Observes
   User Actions & Events
   

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5. MVVM on Android
   Jetpack for the Rescue
   

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6. LiveData
   1. An Observable with LifeCycle
   ability
   2. Instantly notifies the changes in
   the data to the UI
   Observes for updates
   LiveData value updates
   Notifies the observer
   Update the UI
   STARTED
   Or
   RESUMED?
   

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7. ViewModel
   1. Middle man for View & Model
   2. Decouples data from the view to
   survive the configuration
   changes
   3. Never put the references to
   “Context” or “View” inside the
   ViewModel
   

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8. Finally, the Architecture
   All the UI related stuff
   Holds data required by UI and survives
   configuration changes
   Responsible for providing data to ViewModel
   Data sources (or model) such as database or
   from the server
   

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9. Testing
   Who got time for it? My code is perfect.
   

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10. Focus of this session
    https://github.com/wajahatkarim3/MVVM-GDG-Live
    1. ViewModel, LiveData
    2. Kotlin, Extension Methods
    3. Dependency Injection with Koin
    4. Retrofit for Networking
    5. Coil for image downloading
    

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11. Coding Time
    https://github.com/wajahatkarim3/MVVM-GDG-Live
    

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12. Thank you for listening...
    Give us feedback: http://bit.ly/gdgpkfeedback
    @WajahatKarim
    wajahatkarim.com youtube.com/c/wajahatkarim3
    

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