[Mobius '18] Things I wish I knew when I started building Android Libraries/SDK -Vol 2

Building an Android library in the current times is way different than what it used to be earlier. Things have changed considerably and keeping up to date with them is now a necessity rather than just some acquirable knowledge.

This session is a second part to the last year's talk at Droidcon Berlin 2017 which was Vol. 1. In this session, you will dive deeper into best practices and ways of architecting Android libraries. You will get to learn about the common pitfalls and how to overcome them by using the right approach such as leveraging architecture components and making your Android libraries lifecycle-aware. You will also understand how one can leverage Kotlin language when developing Android libraries as well as information around API design and exploring the path to becoming a better Android Library Developer.

By the end of this session, you will be all set to build Android libraries that scale and have API which contributes to the developer's happiness.

Transcript

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2. OSS Android libraries developed
   2
   

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3. Side A
   1. How does Gradle
   process Android
   Libraries
   2. Android Archive(AAR)
   3. Why doesn’t my AAR
   download transitive
   dependencies?
   4. Maven Artifact
   5. POM?
   6. Bundled Proguard
   Configs
   Side B
   7. Modularization
   8. Avoiding Resource
   Name Conflicts
   9. minSdkVersion
   Restriction
   10. Access Visibility vs
   Code Organization
   11. Lifecycle Aware
   Android Library
   12. Auto Init Android
   Library
   3
   @nisrulz
   

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4. How does Gradle process
   Android Libraries
   @nisrulz 4
   

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5. How does Gradle process
   Android Libraries
   repositories{
   jCenter()
   }
   dependencies {
   implementation 'com.example.myawesomelib:1.0.0'
   ...
   }
   5
   @nisrulz
   

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6. How does Gradle process
   Android Libraries
   ● implementation
   6
   @nisrulz
   

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7. ● api
   How does Gradle process
   Android Libraries
   7
   @nisrulz
   

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8. How does Gradle process
   Android Libraries
   ● compileOnly
   8
   @nisrulz
   

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9. Android ARchive(AAR)
   @nisrulz 9
   

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10. AAR = Java ARchive(JAR) + Resources
    10
    @nisrulz
    

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11. AAR = Java ARchive(JAR) + Resources
    Sensey: https://github.com/nisrulz/sensey
    11
    @nisrulz
    

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12. AAR = Java ARchive(JAR) + Resources
    @nisrulz 12
    

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13. Sensey’s build.gradle
    dependencies {
    ...
    // Other testing dependencies
    // Transitive dependency: Support Compat library
    implementation "com.android.support:support-compat:27.0.2"
    }
    13
    @nisrulz
    

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14. Using an AAR as dependency
    @nisrulz 14
    

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15. Using an AAR as dependency
    repositories{
    flatDir{
    dirs 'libs'
    }
    }
    dependencies {
    implementation(name:'nameOfYourAARFileWithoutExtension', ext:'aar')
    }
    @nisrulz 15
    

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16. Using an AAR as dependency
    repositories{
    flatDir{
    dirs 'libs'
    }
    }
    dependencies {
    implementation(name:'nameOfYourAARFileWithoutExtension', ext:'aar')
    }
    // No transitive dependencies of the library are downloaded
    16
    @nisrulz
    

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17. Why doesn’t my AAR
    download transitive
    dependencies?
    @nisrulz 17
    

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18. Sensey’s AAR
    18
    @nisrulz
    

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19. Sensey’s AAR
    No build.gradle file
    19
    @nisrulz
    

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20. Maven Artifact
    20
    @nisrulz
    

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21. Maven Artifact
    21
    @nisrulz
    

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22. POM?
    22
    @nisrulz
    

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23. POM
    ● Project Object Model
    ● XML file
    ● Configuration details used by Maven to build the project
    23
    @nisrulz
    

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24. POM
    POM of Sensey Android Library
    
    
    4.0.0
    com.github.nisrulzsensey1.8.0
    aarsensey
    Android library which makes playing with sensor events & detecting gestures a breeze.
    https://github.com/nisrulz/sensey
    
    
    The Apache Software License, Version 2.0http://www.apache.org/licenses/LICENSE-2.0.txt
    
    
    
    nisrulzNishant Srivastavanisrulz@gmail.com
    
    
    https://github.com/nisrulz/sensey.git
    https://github.com/nisrulz/sensey.git
    https://github.com/nisrulz/sensey
    
    
    
    com.android.support
    support-compat27.0.2
    runtime
    
    
    ...
    
    
    
    24
    @nisrulz
    

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25. POM
    POM of Sensey Android Library
    
    
    4.0.0
    com.github.nisrulzsensey1.8.0
    aarsensey
    Android library which makes playing with sensor events & detecting gestures a breeze.
    https://github.com/nisrulz/sensey
    
    
    The Apache Software License, Version 2.0http://www.apache.org/licenses/LICENSE-2.0.txt
    
    
    
    nisrulzNishant Srivastavanisrulz@gmail.com
    
    
    https://github.com/nisrulz/sensey.git
    https://github.com/nisrulz/sensey.git
    https://github.com/nisrulz/sensey
    
    
    
    com.android.support
    support-compat27.0.2
    runtime
    
    
    ...
    
    
    
    25
    @nisrulz
    

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26. POM
    POM of Sensey Android Library
    
    
    ...
    
    
    com.android.support
    support-compat27.0.2
    runtime
    
    
    ...
    
    
    
    26
    @nisrulz
    

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27. Bundled Proguard Configs
    27
    @nisrulz
    

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28. Bundled Proguard Configs
    android {
    release {
    minifyEnabled true
    // Rules to be used during the AAR generation
    proguardFiles 'proguard-rules-for-building-library.pro'
    // Rules appended to the integrating app
    consumerProguardFiles 'proguard-rules-for-using-library.pro'
    }
    ...
    }
    28
    @nisrulz
    

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29. Bundled Proguard Configs
    Fuel: https://github.com/kittinunf/Fuel
    29
    @nisrulz
    

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30. Bundled Proguard Configs
    30
    @nisrulz
    

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31. Bundled Proguard Configs
    # Fuel’s bundled Proguard file
    # Without specifically keeping this class,
    # callbacks on android don't function properly.
    -keep class com.github.kittinunf.fuel.android.util.AndroidEnvironment
    31
    @nisrulz
    

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32. Bundled Proguard Configs
    # To check the merged configuration
    # Add the below to your current config
    -printconfiguration proguard-merged-config.txt
    32
    @nisrulz
    

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33. Bundled Proguard Configs
    # DON'T DO THIS
    -dontobfuscate
    -optimizations !code/allocation/variable
    # Effectively no optimizations
    -keep public class * {
    public protected *;
    }
    33
    @nisrulz
    

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34. Bundled Proguard Configs
    # DON'T DO THIS
    # Adding the below in library proguard rules disables
    # the optimizations in the Android app
    -dontoptimize
    34
    @nisrulz
    

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35. Modularization
    35
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36. Modularization
    36
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37. Modularization
    EasyDeviceInfo: https://github.com/nisrulz/easydeviceinfo
    37
    @nisrulz
    

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38. Modularization
    dependencies {
    def libVer = {latest_version}
    // Base + Ads Bundled Library
    implementation "com.github.nisrulz:easydeviceinfo:$libVer"
    // Base Library
    implementation "com.github.nisrulz:easydeviceinfo-base:$libVer"
    // Ads Library
    implementation "com.github.nisrulz:easydeviceinfo-ads:$libVer"
    }
    38
    @nisrulz
    

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39. Modularization
    
    
    ...
    
    
    com.github.nisrulz
    easydeviceinfo-ads 2.5.0
    compile
    
    
    com.github.nisrulz
    easydeviceinfo-base 2.5.0
    compile
    
    ...
    
    
    39
    @nisrulz
    

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40. Modularization
    
    
    ...
    
    
    com.github.nisrulz
    easydeviceinfo-ads 2.5.0
    compile
    
    
    com.github.nisrulz
    easydeviceinfo-base 2.5.0
    compile
    
    ...
    
    
    40
    @nisrulz
    

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41. Modularization
    
    
    ...
    
    
    com.github.nisrulz
    easydeviceinfo-ads 2.5.0
    compile
    
    
    com.github.nisrulz
    easydeviceinfo-base 2.5.0
    compile
    
    ...
    
    
    41
    @nisrulz
    

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42. Modularization
    
    
    ...
    
    
    com.github.nisrulz
    easydeviceinfo-common2.5.0
    compile
    
    
    com.google.android.gms
    play-services-ads-identifier16.0.0
    runtime
    
    ...
    
    
    42
    @nisrulz
    

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43. Modularization
    
    
    ...
    
    
    com.github.nisrulz
    easydeviceinfo-common2.5.0
    compile
    
    
    com.google.android.gms
    play-services-ads-identifier16.0.0
    runtime
    
    ...
    
    
    43
    @nisrulz
    

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44. Avoiding Resource Name
    Conflicts
    44
    @nisrulz
    

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45. Conflict occurs between a library & app resource
    > Project will not compile
    What happens when...
    45
    @nisrulz
    

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46. Conflict occurs between 2 libraries integrated in the app
    > Resources from library defined first in build.gradle gets
    included
    What happens when...
    46
    @nisrulz
    

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47. Solution?
    47
    @nisrulz
    

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48. Add a prefix to all your resources.
    Solution?
    48
    @nisrulz
    

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49. Add a prefix to all your resources.
    How?
    Solution?
    49
    @nisrulz
    

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50. Add a prefix to all your resources.
    How?
    ● Enforce this in Android Studio
    Solution?
    50
    @nisrulz
    

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51. Add a prefix to all your resources.
    How?
    ● Enforce this in Android Studio
    ● Declare in build.gradle of library
    android {
    resourcePrefix 'YOUR_PREFIX_' // i.e 'sensey_'
    }
    Solution?
    51
    @nisrulz
    

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52. Solution?
    Resource named ‘app_name’ does not start with the project’s
    resource prefix ‘sensey_’;
    Rename to `sensey_app_name`?
    52
    @nisrulz
    

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53. minSdkVersion Restriction
    53
    @nisrulz
    

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54. minSdkVersion of app >= minSdkVersion of library
    minSdk Restriction
    54
    @nisrulz
    

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55. minSdk Restriction
    55
    @nisrulz
    

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56. Manifest merger failed : uses-sdk:minSdkVersion 14 cannot be smaller
    than version 21 declared in library [:sensey]
    Suggestion:
    + Use a compatible library with a minSdk of at most 14
    + Increase this project's minSdk version to at least 21
    + Use tools:overrideLibrary="com.github.nisrulz.sensey" to force
    usage (may lead to runtime failures)
    minSdk Restriction
    56
    @nisrulz
    

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57. Manifest merger failed : uses-sdk:minSdkVersion 14 cannot be smaller
    than version 21 declared in library [:sensey]
    Suggestion:
    + Use a compatible library with a minSdk of at most 14
    + Increase this project's minSdk version to at least 21
    + Use tools:overrideLibrary="com.github.nisrulz.sensey" to force
    usage (may lead to runtime failures)
    minSdk Restriction
    57
    @nisrulz
    

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58. Manifest merger failed : uses-sdk:minSdkVersion 14 cannot be smaller
    than version 21 declared in library [:sensey]
    Suggestion:
    + Use a compatible library with a minSdk of at most 14
    + Increase this project's minSdk version to at least 21
    + Use tools:overrideLibrary="com.github.nisrulz.sensey" to force
    usage (may lead to runtime failures)
    minSdk Restriction
    58
    @nisrulz
    

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59. xmlns:tools="http://schemas.android.com/tools"
    package="com.github.nisrulz.senseysample">
    
    
    ...
    
    
    minSdk Restriction
    59
    @nisrulz
    

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60. xmlns:tools="http://schemas.android.com/tools"
    package="com.github.nisrulz.senseysample">
    
    
    ...
    
    
    minSdk Restriction
    60
    @nisrulz
    

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61. Access Visibility
    vs
    Code Organization
    61
    @nisrulz
    

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62. Visibility vs Organization
    62
    @nisrulz
    

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63. Visibility vs Organization
    ● Code organized in individual packages; everything is
    public
    63
    @nisrulz
    

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64. Visibility vs Organization
    ● Code organized inside one package; everything is package
    private and only public on demand
    64
    @nisrulz
    

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65. Visibility vs Organization
    ● Code organized inside the module i.e individual
    packages; everything is internal and only public on
    demand (in Kotlin land)
    ● Drawback
    ○ Need dependency on kotlin std library
    65
    @nisrulz
    

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66. Visibility vs Organization
    // file name: exampleLibrary.kt
    // module name: example
    package com.example.library
    66
    @nisrulz
    

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67. Visibility vs Organization
    // file name: exampleLibrary.kt
    // module name: example
    package com.example.library
    // visible inside exampleLibrary.kt
    private fun setup() { ... }
    67
    @nisrulz
    

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68. Visibility vs Organization
    // file name: exampleLibrary.kt
    // module name: example
    package com.example.library
    // visible inside exampleLibrary.kt
    private fun setup() { ... }
    // property is visible everywhere
    public var name: String = "ExampleLib"
    // setter is visible only in exampleLibrary.kt
    private set{...}
    68
    @nisrulz
    

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69. Visibility vs Organization
    // file name: exampleLibrary.kt
    // module name: example
    package com.example.library
    // visible inside exampleLibrary.kt
    private fun setup() { ... }
    // property is visible everywhere
    public var name: String = "ExampleLib"
    // setter is visible only in exampleLibrary.kt
    private set{...}
    // visible inside the module i.e example
    internal val debugTag = "Example-Debug"
    69
    @nisrulz
    

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70. Lifecycle-Aware
    Android Library
    70
    @nisrulz
    

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71. Lifecycle Components
    Classes designed to help deal with Android
    lifecycle
    ● Lifecycle
    ● LifecycleOwner
    ● LifecycleObserver
    71
    @nisrulz
    

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72. Lifecycle Components
    Classes designed to help deal with Android
    lifecycle
    72
    @nisrulz
    

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73. Lifecycle Components
    Classes designed to help deal with Android
    lifecycle
    i.e Activity, Fragment, Service, Custom
    73
    @nisrulz
    

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74. Lifecycle
    class MainActivity extends AppCompatActivity() {...}
    74
    @nisrulz
    

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75. Lifecycle
    class MainActivity extends AppCompatActivity() {...}
    public class AppCompatActivity extends FragmentActivity{...}
    75
    @nisrulz
    

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76. Lifecycle
    class MainActivity extends AppCompatActivity() {...}
    public class AppCompatActivity extends FragmentActivity{...}
    public class FragmentActivity extends SupportActivity {
    ...
    public Lifecycle getLifecycle() {
    return super.getLifecycle();
    }
    ...
    }
    76
    @nisrulz
    

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77. LifecycleObserver
    dependencies {
    def lifecycleVer = "2.0.0"
    // Runtime
    implementation "androidx.lifecycle:lifecycle-runtime:$lifecycleVer"
    // Annotation Support
    annotationProcessor "androidx.lifecycle:lifecycle-compiler:$lifecycleVer"
    ...
    }
    77
    @nisrulz
    

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78. LifecycleObserver
    public class AwesomeLib implements LifecycleObserver {
    @OnLifecycleEvent(Lifecycle.Event.ON_CREATE)
    public void init() { ... }
    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    public void libOnStart() { ... }
    ...
    @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
    public void cleanup() { ... }
    }
    78
    @nisrulz
    

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79. LifecycleOwner
    class MainActivity : AppCompatActivity() {
    val awesomeLib = AwesomeLib()
    override fun onResume() {
    ...
    // Add lifecycle observer
    lifecycle.addObserver(awesomeLib)
    }
    override fun onStop() {
    ...
    // Remove lifecycle observer
    lifecycle.removeObserver(awesomeLib)
    }
    }
    79
    @nisrulz
    

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80. LifecycleAware Library
    80
    @nisrulz
    

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81. ProcessLifecycleOwner
    Class that tracks the lifecycle of
    whole application process
    81
    @nisrulz
    

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82. ProcessLifecycleOwner
    dependencies {
    // For ProcessLifecycleOwner
    implementation "androidx.lifecycle:lifecycle-extensions:2.0.0"
    ...
    }
    82
    @nisrulz
    

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83. ProcessLifecycleOwner
    Does something weird…
    83
    @nisrulz
    

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84. ProcessLifecycleOwner
    Does something weird…
    Adding lifecycle-extensions artifact
    > automatically adds element to the merged
    manifest
    84
    @nisrulz
    

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85. ProcessLifecycleOwner
    85
    @nisrulz
    

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86. ProcessLifecycleOwner
    
    
    ...
    android:name="androidx.lifecycle.ProcessLifecycleOwnerInitializer"
    android:authorities="com.example.app.lifecycle-process"
    android:exported="false"
    android:multiprocess="true" />
    
    
    86
    @nisrulz
    

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87. ProcessLifecycleOwner
    
    
    ...
    android:name="androidx.lifecycle.ProcessLifecycleOwnerInitializer"
    android:authorities="com.example.app.lifecycle-process"
    android:exported="false"
    android:multiprocess="true" />
    
    
    87
    @nisrulz
    

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88. ProcessLifecycleOwner
    
    
    ...
    android:name="android.arch.lifecycle.ProcessLifecycleOwnerInitializer"
    android:authorities="com.example.app.lifecycle-trojan"
    android:exported="false"
    android:multiprocess="true" />
    
    
    88
    @nisrulz
    Pre-AndroidX
    

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89. ProcessLifecycleOwner
    
    
    ...
    android:name="android.arch.lifecycle.ProcessLifecycleOwnerInitializer"
    android:authorities="com.example.app.lifecycle-trojan"
    android:exported="false"
    android:multiprocess="true" />
    
    
    89
    @nisrulz
    Pre-AndroidX
    

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90. ProcessLifecycleOwner
    90
    @nisrulz
    Pre-AndroidX
    

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91. ProcessLifecycleOwner
    
    
    ...
    android:name="androidx.lifecycle.ProcessLifecycleOwnerInitializer"
    android:authorities="com.example.app.lifecycle-process"
    android:exported="false"
    android:multiprocess="true" />
    
    
    91
    @nisrulz
    AndroidX
    

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92. ProcessLifecycleOwner
    
    
    ...
    android:name="androidx.lifecycle.ProcessLifecycleOwnerInitializer"
    android:authorities="com.example.app.lifecycle-process"
    android:exported="false"
    android:multiprocess="true" />
    
    
    92
    @nisrulz
    AndroidX
    

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93. ProcessLifecycleOwner
    // Internal class to initialize Lifecycles.
    public class ProcessLifecycleOwnerInitializer extends ContentProvider {
    @Override
    public boolean onCreate() {
    ...
    ProcessLifecycleOwner.init(getContext());
    return true;
    }
    ...
    }
    93
    @nisrulz
    

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94. ProcessLifecycleOwner
    Why?
    To invoke ProcessLifecycleOwner as soon as process
    starts
    94
    @nisrulz
    

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95. ProcessLifecycleOwner
    Why?
    To invoke ProcessLifecycleOwner as soon as process
    starts
    Drawback?
    Initializes ProcessLifecycleOwner even if your app
    does not use it!
    95
    @nisrulz
    

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96. ProcessLifecycleOwner
    How to get rid of it in app?
    96
    @nisrulz
    

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97. ProcessLifecycleOwner
    How to get rid of it in app?
    Use Merge rule marker in app’s AndroidManifest.xml:
    // Remove marked element from the merged manifest
    tools:node="remove"
    97
    @nisrulz
    

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98. ProcessLifecycleOwner
    
    ...
    android:name="androidx.lifecycle.ProcessLifecycleOwnerInitializer"
    android:authorities="${applicationId}.lifecycle-process"
    xmlns:tools="http://schemas.android.com/tools"
    tools:node="remove"
    />
    
    98
    @nisrulz
    App’s AndroidManifest.xml
    

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99. ProcessLifecycleOwner
    
    ...
    android:name="androidx.lifecycle.ProcessLifecycleOwnerInitializer"
    android:authorities="${applicationId}.lifecycle-process"
    xmlns:tools="http://schemas.android.com/tools"
    tools:node="remove"
    />
    
    99
    @nisrulz
    App’s AndroidManifest.xml
    

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100. ProcessLifecycleOwner
     
     ...
     android:name="androidx.lifecycle.ProcessLifecycleOwnerInitializer"
     android:authorities="${applicationId}.lifecycle-process"
     xmlns:tools="http://schemas.android.com/tools"
     tools:node="remove"
     />
     
     100
     @nisrulz
     App’s AndroidManifest.xml
     

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101. ProcessLifecycleOwner
     
     ...
     android:name="androidx.lifecycle.ProcessLifecycleOwnerInitializer"
     android:authorities="${applicationId}.lifecycle-process"
     xmlns:tools="http://schemas.android.com/tools"
     tools:node="remove"
     />
     
     101
     @nisrulz
     App’s AndroidManifest.xml
     

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102. Auto Initialize
     Android Library
     102
     @nisrulz
     

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103. AutoInit Android Library
     Android Libraries need Android context to handle simple tasks such as
     ● Hook into Android Runtime
     ● Access app resources
     ● Use System Services
     ● Register BroadcastReceiver
     103
     @nisrulz
     

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104. AutoInit Android Library
     public class MyApplication extends Application {
     @Override
     public void onCreate() {
     super.onCreate();
     // Init android library
     MyAwesomeLibrary.init(this);
     }
     }
     104
     @nisrulz
     

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105. AutoInit Android Library
     public class MyApplication extends Application {
     @Override
     public void onCreate() {
     super.onCreate();
     // Init android library
     MyAwesomeLibrary.init(this);
     }
     }
     105
     @nisrulz
     

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106. AutoInit Android Library
     public class MyApplication extends Application {
     @Override
     public void onCreate() {
     super.onCreate();
     // Init android library
     MyAwesomeLibrary.init(this);
     }
     }
     106
     @nisrulz
     

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107. AutoInit Android Library
     android:icon="@mipmap/ic_launcher"
     android:label="@string/app_name"
     android:name=".MyApplication"
     ... >
     107
     @nisrulz
     

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108. AutoInit Android Library
     android:icon="@mipmap/ic_launcher"
     android:label="@string/app_name"
     android:name=".MyApplication"
     ... >
     108
     @nisrulz
     

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109. AutoInit Android Library
     ContentProvider can be used to simplify the process.
     109
     @nisrulz
     

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110. AutoInit Android Library
     ContentProvider can be used to simplify the process.
     Simply because ContentProvider
     ● Is created and initialized (on the main thread)
     before all other components
     ● Participate in manifest merging at build time.
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111. AutoInit Android Library
     public class AwesomeLibInitProvider extends ContentProvider {
     ...
     @Override
     public boolean onCreate() {
     // get the context (Application context)
     Context context = getContext();
     // initialize AwesomeLib here
     AwesomeLib.getInstance().init(context);
     return false;
     }
     ...
     }
     111
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112. AutoInit Android Library
     public class AwesomeLibInitProvider extends ContentProvider {
     ...
     @Override
     public boolean onCreate() {
     // get the context (Application context)
     Context context = getContext();
     // initialize AwesomeLib here
     AwesomeLib.getInstance().init(context);
     return false;
     }
     ...
     }
     112
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113. AutoInit Android Library
     package="github.nisrulz.sample.awesomelib">
     
     android:name=".AwesomeLibInitProvider"
     android:authorities="${applicationId}.awesomelibinitprovider"
     android:enabled="true"
     android:exported="false"/>
     
     
     113
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114. AutoInit Android Library
     package="github.nisrulz.sample.awesomelib">
     
     android:name=".AwesomeLibInitProvider"
     android:authorities="${applicationId}.awesomelibinitprovider"
     android:enabled="true"
     android:exported="false"/>
     
     
     114
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115. AutoInit Android Library
     package="github.nisrulz.sample.awesomelib">
     
     android:name=".AwesomeLibInitProvider"
     android:authorities="${applicationId}.awesomelibinitprovider"
     android:enabled="true"
     android:exported="false"/>
     
     
     115
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116. AutoInit Android Library
     package="github.nisrulz.sample.awesomelib">
     
     android:name=".AwesomeLibInitProvider"
     android:authorities="${applicationId}.awesomelibinitprovider"
     android:enabled="true"
     android:exported="false"/>
     
     
     116
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117. AutoInit Android Library
     ContentProvider can be used to simplify the process.
     117
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118. AutoInit Android Library
     ContentProvider can be used to simplify the process.
     Challenges:
     ● There can be only one Content Provider with a given
     “authority” string
     ● Only run on main thread
     118
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119. AutoInit Android Library
     ContentProvider can be used to simplify the process.
     119
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120. AutoInit Android Library
     ContentProvider can be used to simplify the process.
     Why this is a bad idea:
     ● Increases startup time
     ● Bloats applications even when not used
     ● Abusing functionality of ContentProvider
     120
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121. AutoInit Android Library
     ContentProvider can be used to simplify the process.
     Why this is a bad idea:
     ● Increases startup time (Solution: async initialize)
     ● Bloats applications even when not used
     ● Abusing functionality of ContentProvider
     121
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122. AutoInit Android Library
     Some android libraries that use this...
     122
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123. AutoInit Android Library
     ProcessLifecycleOwner
     [androidx.lifecycle:lifecycle-extensions:2.0.0]
     
     android:name="androidx.lifecycle.ProcessLifecycleOwnerInitializer"
     android:authorities="${applicationId}.lifecycle-process"
     android:exported="false"
     android:multiprocess="true" />
     
     123
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124. AutoInit Android Library
     Firebase
     [com.google.firebase:firebase-common:16.0.5]
     
     android:name="com.google.firebase.provider.FirebaseInitProvider"
     android:authorities="${applicationId}.firebaseinitprovider"
     android:exported="false"
     android:initOrder="100" />
     
     124
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125. AutoInit Android Library
     Facebook-Core
     [com.facebook.android:facebook-core:4.34.0]
     
     android:name="com.facebook.internal.FacebookInitProvider"
     android:authorities="${applicationId}.FacebookInitProvider"
     android:exported="false" />
     
     125
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126. AutoInit Android Library
     Facebook-Marketing
     [com.facebook.android:facebook-marketing:4.34.0]
     
     android:name="com.facebook.marketing.internal.MarketingInitProvider"
     android:authorities="${applicationId}.MarketingInitProvider"
     android:exported="false" />
     
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127. AutoInit Android Library
     Crashlytics
     [com.crashlytics.sdk.android:crashlytics:2.9.5]
     
     android:name="com.crashlytics.android.CrashlyticsInitProvider"
     android:authorities="${applicationId}.crashlyticsinitprovider"
     android:exported="false"
     android:initOrder="90" />
     
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128. AutoInit Android Library
     Picasso
     // Pre - v2.71828
     Picasso.with(this).load("......").into(imageView);
     // After - v2.71828
     Picasso.get().load("......").into(imageView);
     128
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129. AutoInit Android Library
     Picasso
     // Pre - v2.71828
     Picasso.with(this).load("......").into(imageView);
     // After - v2.71828
     Picasso.get().load("......").into(imageView);
     129
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130. AutoInit Android Library
     Picasso
     [com.squareup.picasso:picasso:2.71828]
     
     android:name=".PicassoContentProvider"
     android:authorities="${applicationId}.com.squareup.picasso3"
     android:exported="false"/>
     
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131. Links/References
     Android Libraries I have built:
     https://github.com/nisrulz/nisrulz.github.io#open-source-co
     ntributions
     Auto initialize android library example:
     https://github.com/nisrulz/android-examples/tree/develop/Au
     toInitLibrary
     Lifecycle Aware android library example:
     https://github.com/nisrulz/android-examples/tree/develop/Li
     feCycleCompForLib
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132. twitter.com/nisrulz
     github.com/nisrulz
     www.nisrulz.com
     132
     

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133. twitter.com/nisrulz
     github.com/nisrulz
     www.nisrulz.com
     133
     

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