Droidcon London: Preparing your app for Google Play Instant

Android Instant applications are becoming increasingly available, and thanks to the work from the Android platform team can already be installed on devices running Android Lollipop or later.

As an application developer for a large application, or one with plenty of untested legacy code, preparing an application that might be tightly coupled into a single module requires us to carefully de-tangle and move concerns to independent modules.

This talk covers how we managed to prepare our application for instant apps by breaking off base elements and isolating essential key features into self-contained, independent modules, with all the difficulties that this entails and how you can avoid the common pain points and pitfalls.

Transcript

1. Preparing your app for Google Play Instant
   Droidcon London 2018
   ashdavies.io - @askashdavies
   

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5. !
   

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7. !
   Friction
   

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10. !
    

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11. < />
    

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14. Lollipop
    

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16. 
    

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17. Try Now
    

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18. 
    android:name="default-url"
    android:value="https://example.com/welcome" />
    
    

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19. Performance
    

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20. Security
    

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21. !
    HTTPS
    

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22. Smart Lock
    

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23. Auth.CredentialsApi.save(mCredentialsClient, credential).setResultCallback(
    new ResultCallback() {
    @Override
    public void onResult(Status status) {
    if (status.isSuccess()) {
    // Credentials were saved
    } else {
    if (status.hasResolution()) {
    // Try to resolve the save request. This will prompt the user if
    // the credential is new.
    try {
    status.startResolutionForResult(this, RC_SAVE);
    } catch (IntentSender.SendIntentException e) {
    // Could not resolve the request
    }
    }
    }
    }
    });
    

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24. !
    Play Billing Library
    

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25. !
    Runtime Permissions
    

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26. • ACCESS_COARSE_LOCATION
    • ACCESS_FINE_LOCATION
    • ACCESS_NETWORK_STATE
    • BILLING (Deprecated as of Play Billing Library 1.0)
    • CAMERA
    • INSTANT_APP_FOREGROUND_SERVICE (Only in Android Oreo)
    • INTERNET
    • READ_PHONE_NUMBERS (Only in Android Oreo)
    • RECORD_AUDIO
    • VIBRATE
    

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27. Limitations
    

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28. ! ⛏
    

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29. Background Services
    

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30. Push Notifications
    

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31. External Storage
    

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32. !
    Local Storage
    

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33. Instant <-> Installed
    

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34. Cookie API
    

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35. Size Limit (4 Mb)
    

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36. Size Limit (4 Mb) (10 Mb)
    

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39. The Monolith
    

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40. Location Input
    

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42. Dependency
    Graph
    

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43. @Component
    

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46. Flat Hierarchy
    

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49. Dynamic Feature
    

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51. Optimisations
    • Code minification (minifyEnabled)
    • Resource shrinking (shrinkResources)
    • Optimised SVG assets (bit.ly/2SeZePQ)
    • Configuration splits (splits { })
    • Third party SDKs
    !
    

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53. Proguard / R8
    

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54. Third Party SDKs
    

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55. Data Binding
    !
    Error: Currently, data binding does not work for non-base feature modules.
    Please, move data binding code to the base feature module.
    See https://issuetracker.google.com/63814741 for details
    

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56. Data Binding
    !
    android.enableExperimentalFeatureDatabinding=true
    

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57. Navigation
    Intent(context, CalculatorActivity::class.java)
    

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58. Navigation
    Intent(context, CalculatorActivity::class.java)
    

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59. App Links
    

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60. 
    
    
    
    
    android:path="/baufinanzierung/finanzierungsrechner/"
    android:scheme="https"/>
    
    
    

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61. 
    
    
    
    
    android:path="/baufinanzierung/finanzierungsrechner/"
    android:scheme="https"/>
    
    
    

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62. Intent Extras
    val intent = Intent(context, CalculatorActivity::class.java)
    intent.putExtra("location", "Berlin")
    

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63. ❗
    

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64. Query Params
    intent.data?.getQueryParameter("location")
    

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65. ?
    

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66. Query Params
    val geocode = intent.data?.getQueryParameter("location")
    val label = intent.data?.getQueryParameter("label")
    val region = if (geocode != null && label != null) Region(geocode, label)
    else null
    

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67. Query Params
    data class Region(val geocode: String, val label: String) {
    companion object {
    operator fun invoke(
    geocode: String?,
    label: String?
    ) : Region(
    geocode ?: "1276001010",
    label ?: "Berlin - Mitte (Mitte)"
    )
    }
    }
    

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68. Query Params
    val region = Region(
    intent.data?.getQueryParameter("location"),
    intent.data?.getQueryParameter("label")
    )
    

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69. Verify Site Associations
    

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70. keytool -list -v -keystore release.keystore
    

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71. [{
    "relation": ["delegate_permission/common.handle_all_urls"],
    "target": {
    "namespace": "android_app",
    "package_name": "de.is24.android",
    "sha256_cert_fingerprints": ["..."]
    }
    }]
    

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73. Emulator
    Support
    

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74. Topeka
    github.com/googlesamples/android-topeka
    

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75. Plaid
    github.com/nickbutcher/plaid
    

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76. Next Steps
    

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77. Cheers!
    !
    ashdavies.io - @askashdavies
    

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