Library Developer Confidential

For the last several years of my career I have been tasked with creating and maintaining libraries that handle complex bluetooth communication and Android UI. In this talk we will go over setting up library projects for success, bootstrapping an architecture that will allow you to grow with minimal collisions and boilerplate, how to build/deploy multiple libraries while trying to debug without losing your sanity and more. At the end of this talk it is my hope you will feel confident enough to start and maintain your own library project. This talk is part gradle, part java/kotlin and absolutely free of Git Submodules.

Transcript

1. Elliott Chenger @echenger Library Developer Confidential
3. Wall-E Artoo
4. AAR == Android Archive
5. AAR == Android Archive Just a fancy zip
6. Anatomy of an AAR classes.jar AndroidManifest.xml Res R.txt Public.txt
7. Anatomy of an AAR assets JNI Lib JARs Proguard.txt lint.jar
8. Why should you build a library?
9. Faster builds Architecture and Portability Android App Bundles and Instant Apps
10. Speed
11. App
12. class Pug { companion object { val isHungry = true } }
13. class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) } }
14. :app 14s
15. class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) val textView = findViewById<TextView>(R.id.text_view) textView.text = "Pugs are always hungry ${Pug.isHungry}" } }
16. :app 14s
17. App
18. App Lib
19. class Pug { companion object { val isHungry = true } }
20. class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) } }
21. :app 7s :pugs 7s
22. –Library Skeptic “Nothing changed!”
23. class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) val textView = findViewById<TextView>(R.id.text_view) textView.text = "Pugs are always hungry ${Pug.isHungry()}" } }
24. :app 7s :pugs UP-TO-DATE
25. :app 7s :pugs UP-TO-DATE
26. Build Caching Added 3.5
27. Build Caching Added 3.5 Support for Build Caching Added 3.0.0
28. - Gradle Documentation “The best way to do work faster is to not do work that doesn’t need doing.”
30. Feature Based Architecture
31. App
32. App Feat. A Feat. B
33. Removing features is easier
34. App Feat. A Feat. B
35. App Feat. A
36. dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version" implementation 'com.android.support:appcompat-v7:27.1.1' implementation project(':pugs') implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' }
37. dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version" implementation 'com.android.support:appcompat-v7:27.1.1' implementation project(':pugs') implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' }
38. dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version" implementation 'com.android.support:appcompat-v7:27.1.1' implementation project(':pugs') implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' }
39. dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version" implementation 'com.android.support:appcompat-v7:27.1.1' implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' }
40. Sharing features
41. App 1 Feat. A App 2
42. Android App Bundles and Instant Apps
43. App
44. App Feature A Instant App
45. App Feature A Instant App
46. App Feature A Instant App Util Lib
47. Project Setup
48. Single Project
49. Only deploys in one app? Does it need to be shared with others?
50. Only deploys in one app? Yes Does it need to be shared with others? No
51. App Lib Single Project
56. Settings.gradle include ':app', ':pugs'
57. Build.gradle dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation 'com.android.support:appcompat-v7:26.1.0' implementation 'com.android.support:support-annotations:27.1.1' implementation 'com.android.support.constraint:constraint-layout:1.1.2' implementation project(":pugs") testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core: 3.0.2' }
58. Build.gradle dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation 'com.android.support:appcompat-v7:26.1.0' implementation 'com.android.support:support-annotations:27.1.1' implementation 'com.android.support.constraint:constraint-layout:1.1.2' implementation project(":pugs") testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core: 3.0.2' }
59. Multi-Project
60. Only deploys in one app? Does it need to be shared with others?
61. Only deploys in one app? No Does it need to be shared with others? Yes
62. App Lib Multi-Project
63. App Lib Multi-Project Test App
64. App Lib Multi-Project Test App
65. AAR in a Libs Directory Library.aar
66. dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version" implementation 'com.android.support:appcompat-v7:27.1.1' implementation files('libs/pugs-debug.aar') implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' }
67. dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version" implementation 'com.android.support:appcompat-v7:27.1.1' implementation files('libs/pugs-debug.aar') implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' }
68. OR
69. AAR in a Libs Directory repositories{ flatDir { dirs '../libs' } mavenCentral() }
70. AAR in a Libs Directory dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation 'com.android.support:appcompat-v7:26.1.0' implementation 'com.android.support:support-annotations:27.1.1' implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' //Including a local gradle module implementation project(":pugs") //Including a local aar implementation(name:'beers-debug', ext:'aar') implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version" }
71. AAR in a Libs Directory dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation 'com.android.support:appcompat-v7:26.1.0' implementation 'com.android.support:support-annotations:27.1.1' implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' //Including a local gradle module implementation project(":pugs") //Including a local aar implementation(name:'beers-debug', ext:'aar') implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version" }
72. 07-01 17:50:12.887 4565-4565/com.omitneedlesscode.myapplication E/AndroidRuntime: FATAL EXCEPTION: main Process: com.omitneedlesscode.myapplication, PID: 4565 java.lang.NoClassDefFoundError: Failed resolution of: Ltimber/log/Timber$DebugTree; at com.omitneedlesscode.beers.BeerApplication.onCreate(BeerApplication.kt:10) at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1118) at android.app.ActivityThread.handleBindApplication(ActivityThread.java:5791) at android.app.ActivityThread.-wrap1(Unknown Source:0) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1661) at android.os.Handler.dispatchMessage(Handler.java:105) at android.os.Looper.loop(Looper.java:164) at android.app.ActivityThread.main(ActivityThread.java:6541) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
73. 07-01 17:50:12.887 4565-4565/com.omitneedlesscode.myapplication E/AndroidRuntime: FATAL EXCEPTION: main Process: com.omitneedlesscode.myapplication, PID: 4565 java.lang.NoClassDefFoundError: Failed resolution of: Ltimber/log/Timber$DebugTree; at com.omitneedlesscode.beers.BeerApplication.onCreate(BeerApplication.kt:10) at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1118) at android.app.ActivityThread.handleBindApplication(ActivityThread.java:5791) at android.app.ActivityThread.-wrap1(Unknown Source:0) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1661) at android.os.Handler.dispatchMessage(Handler.java:105) at android.os.Looper.loop(Looper.java:164) at android.app.ActivityThread.main(ActivityThread.java:6541) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
74. public final fun getBreweries():kotlin.collections.List<kotlin.String> { /* compiled code */ } Note: AARs don’t contain source
75. AAR in a Libs Directory Library.aar
76. AAR in a Libs Directory Library.aar + Copy of Dependencies
77. AAR in a Libs Directory dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation 'com.android.support:appcompat-v7:26.1.0' implementation 'com.android.support:support-annotations:27.1.1' implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' //Including a local gradle module implementation project(":pugs") //Including a local aar implementation(name:'beers-debug', ext:’aar’) implementation 'com.jakewharton.timber:timber:4.7.1' implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version" }
78. AAR in a Libs Directory dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation 'com.android.support:appcompat-v7:26.1.0' implementation 'com.android.support:support-annotations:27.1.1' implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' //Including a local gradle module implementation project(":pugs") //Including a local aar implementation(name:'beers-debug', ext:’aar’) implementation 'com.jakewharton.timber:timber:4.7.1' implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version" }
79. AAR in a Libs Directory •Easy to use •Quick to test changes •Copy over library dependencies •Project switching •GIT LFS or your repo size will balloon •Hard to debug Pros Cons
80. App Lib Gradle Composite Project Test App
81. App Lib Gradle Composite Project Test App Lib Test App
82. Settings.gradle include ':app' includeBuild('../Beers'){ dependencySubstitution{ substitute module('com.omitneedlesscode:beers') with project(':beers') } }
83. Note // Gradle Composite Builds won't work with local AARs implementation(name:'beers-debug', ext:'aar') // They do work with Maven Dependencies implementation 'com.omitneedlesscode:beers:1.0'
84. Note // Gradle Composite Builds won't work with local AARs implementation(name:'beers-debug', ext:'aar') // They do work with Maven Dependencies implementation 'com.omitneedlesscode:beers:1.0'
88. •Doesn’t impact other developers •Can change code in both library and app •No major modifications to the library project gradle files •Easier to debug •Newer feature so there have been some small bugs •To turn off composite mode may need to re- import library project •Can’t use with provided aars in Lib Pros Cons Gradle Composite Project
89. What is a Maven Dependency?
90. –Maven Documentation “A repository in Maven is used to hold build artifacts and dependencies of varying types.”
91. –Maven Documentation “A repository in Maven is used to hold build artifacts and dependencies of varying types.”
92. Library.aar + pom.xml
93. Maven Repo Library.aar + pom.xml
94. Maven Dependency Naming Convention <group id>:<artifact id>:<version> 'com.omitneedlesscode:beers:1.0'
95. How do you create a Maven Dependency?
96. apply plugin: 'maven-publish'
97. publishing{ publications{ aar(MavenPublication){ groupId 'com.omitneedlesscode' artifactId 'beers' version = android.defaultConfig.versionName artifact new File('build/outputs/aar/beers-debug.aar') pom.withXml { def dependencies = asNode().appendNode('dependencies') configurations.implementation.allDependencies.each{ if(it.name!="unspecified"){ def dependency = dependencies.appendNode('dependency') dependency.appendNode('groupId', it.group) dependency.appendNode('artifactId', it.name) dependency.appendNode('version', it.version) } } } } } }
98. publishing{ publications{ aar(MavenPublication){ groupId 'com.omitneedlesscode' artifactId 'beers' version = android.defaultConfig.versionName artifact new File('build/outputs/aar/beers-debug.aar') pom.withXml { def dependencies = asNode().appendNode('dependencies') configurations.implementation.allDependencies.each{ if(it.name!="unspecified"){ def dependency = dependencies.appendNode('dependency') dependency.appendNode('groupId', it.group) dependency.appendNode('artifactId', it.name) dependency.appendNode('version', it.version) } } } } } }
99. publishing{ publications{ aar(MavenPublication){ groupId 'com.omitneedlesscode' artifactId 'beers' version = android.defaultConfig.versionName artifact new File('build/outputs/aar/beers-debug.aar') pom.withXml { def dependencies = asNode().appendNode('dependencies') configurations.implementation.allDependencies.each{ if(it.name!="unspecified"){ def dependency = dependencies.appendNode('dependency') dependency.appendNode('groupId', it.group) dependency.appendNode('artifactId', it.name) dependency.appendNode('version', it.version) } } } } } }
100. publishing{ publications{ aar(MavenPublication){ groupId 'com.omitneedlesscode' artifactId 'beers' version = android.defaultConfig.versionName artifact new File('build/outputs/aar/beers-debug.aar') pom.withXml { def dependencies = asNode().appendNode('dependencies') configurations.implementation.allDependencies.each{ if(it.name!="unspecified"){ def dependency = dependencies.appendNode('dependency') dependency.appendNode('groupId', it.group) dependency.appendNode('artifactId', it.name) dependency.appendNode('version', it.version) } } } } } }
101. publishing{ publications{ aar(MavenPublication){ groupId 'com.omitneedlesscode' artifactId 'beers' version = android.defaultConfig.versionName artifact new File('build/outputs/aar/beers-debug.aar') pom.withXml { def dependencies = asNode().appendNode('dependencies') configurations.implementation.allDependencies.each{ if(it.name!="unspecified"){ def dependency = dependencies.appendNode('dependency') dependency.appendNode('groupId', it.group) dependency.appendNode('artifactId', it.name) dependency.appendNode('version', it.version) } } } } } }
102. How do I test my maven dependency?
103. Maven Repo Library.aar + pom.xml
104. Maven Repo Library.aar + pom.xml Local
106. 11:06:46 PM: Executing task 'publishToMavenLocal'... Executing tasks: [publishToMavenLocal] Configuration on demand is an incubating feature. :beers:generatePomFileForAarPublication :beers:publishAarPublicationToMavenLocal :beers:publishToMavenLocal BUILD SUCCESSFUL in 5s 2 actionable tasks: 2 executed 11:06:51 PM: Task execution finished 'publishToMavenLocal'.
107. ➜ ~ cd ~/.m2/
108. /Users/<username>/.m2/repository/com/omitneedlesscode/beers/1.0
109. ➜ 1.0 ls beers-1.0.aar beers-1.0.pom
110. repositories{ flatDir { dirs '../libs' } mavenCentral() mavenLocal() }
111. repositories{ flatDir { dirs '../libs' } mavenCentral() mavenLocal() }
112. dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation 'com.android.support:appcompat-v7:26.1.0' implementation 'com.android.support:support-annotations:27.1.1' implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' //Including a local gradle module implementation project(":pugs") //Including a local aar implementation ‘com.omitneedlesscode:beers:1.0' implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version" }
113. dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation 'com.android.support:appcompat-v7:26.1.0' implementation 'com.android.support:support-annotations:27.1.1' implementation 'com.android.support.constraint:constraint-layout:1.1.2' testImplementation 'junit:junit:4.12' androidTestImplementation 'com.android.support.test:runner:1.0.2' androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2' //Including a local gradle module implementation project(":pugs") //Including a local aar implementation 'com.omitneedlesscode:beers:1.0' implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version" }
114. Scripting
115. App Lib 1 build.gradle build.gradle
116. App Lib 1 build.gradle build.gradle Lib 2 build.gradle
117. App Lib 1 build.gradle build.gradle Lib 2 build.gradle … Lib N build.gradle
118. Shared Gradle Scripts
119. publishing{ publications{ aar(MavenPublication){ groupId 'com.omitneedlesscode' artifactId 'pugs' version = android.defaultConfig.versionName artifact new File('build/outputs/aar/pugs-debug.aar') pom.withXml { def dependencies = asNode().appendNode('dependencies') configurations.implementation.allDependencies.each{ if(it.name!="unspecified"){ def dependency = dependencies.appendNode('dependency') dependency.appendNode('groupId', it.group) dependency.appendNode('artifactId', it.name) dependency.appendNode('version', it.version) } } } } } }
120. publishing{ publications{ aar(MavenPublication){ groupId 'com.omitneedlesscode' artifactId 'pugs' version = android.defaultConfig.versionName artifact new File('build/outputs/aar/pugs-debug.aar') pom.withXml { def dependencies = asNode().appendNode('dependencies') configurations.implementation.allDependencies.each{ if(it.name!="unspecified"){ def dependency = dependencies.appendNode('dependency') dependency.appendNode('groupId', it.group) dependency.appendNode('artifactId', it.name) dependency.appendNode('version', it.version) } } } } } }
121. publishing{ publications{ aar(MavenPublication){ groupId 'com.omitneedlesscode' artifactId 'beers' version = android.defaultConfig.versionName artifact new File('build/outputs/aar/beers-debug.aar') pom.withXml { def dependencies = asNode().appendNode('dependencies') configurations.implementation.allDependencies.each{ if(it.name!="unspecified"){ def dependency = dependencies.appendNode('dependency') dependency.appendNode('groupId', it.group) dependency.appendNode('artifactId', it.name) dependency.appendNode('version', it.version) } } } } } }
122. publishing{ publications{ aar(MavenPublication){ groupId 'com.omitneedlesscode' artifactId 'beers' version = android.defaultConfig.versionName artifact new File('build/outputs/aar/beers-debug.aar') pom.withXml { def dependencies = asNode().appendNode('dependencies') configurations.implementation.allDependencies.each{ if(it.name!="unspecified"){ def dependency = dependencies.appendNode('dependency') dependency.appendNode('groupId', it.group) dependency.appendNode('artifactId', it.name) dependency.appendNode('version', it.version) } } } } } }
123. artifact new File('build/outputs/aar/pugs-debug.aar') artifact new File('build/outputs/aar/beers-debug.aar') artifactId 'beers' artifactId 'pugs'
124. publish.gradle
125. apply plugin: 'maven-publish' ext.filePath = '' ext.expectedArtifactId = '' ext.expectedGroupId = '' ext.expectedVersion = '' publishing { publications { aar(MavenPublication) { groupId expectedGroupId artifactId expectedArtifactId version = expectedVersion artifact new File(filePath) pom.withXml { def dependencies = asNode().appendNode('dependencies') configurations.implementation.allDependencies.each { if (it.name != "unspecified") { def dependency = dependencies.appendNode('dependency') dependency.appendNode('groupId', it.group) dependency.appendNode('artifactId', it.name) dependency.appendNode('version', it.version) } } } } } }
126. ext.filePath = '' ext.expectedArtifactId = '' ext.expectedGroupId = '' ext.expectedVersion = ''
127. apply from: '../publish.gradle' ext.filePath = 'build/outputs/aar/cars-debug.aar' ext.expectedArtifactId = 'cars' ext.expectedGroupId = 'com.omitneedlesscode' ext.expectedVersion = app_version
128. Remote Shared Gradle Scripts
129. apply from: “https://foo.bar/publish.gradle” ext.filePath = 'build/outputs/aar/cars-debug.aar' ext.expectedArtifactId = 'cars' ext.expectedGroupId = 'com.omitneedlesscode' ext.expectedVersion = app_version
130. apply from: “https://foo.bar/publish.gradle” ext.filePath = 'build/outputs/aar/cars-debug.aar' ext.expectedArtifactId = 'cars' ext.expectedGroupId = 'com.omitneedlesscode' ext.expectedVersion = app_version
131. App Lib 1 build.gradle build.gradle Lib 2 build.gradle … Lib N build.gradle publish.gradle
132. ./gradlew --profile --recompile-scripts --offline assembleDebug
133. Avoid Creating Dependency Hell
134. App Lib glide:3.8.0 glide:4.7.1
135. 21:28:57.809 13647-13647/com.omitneedlesscode.nodependency E/AndroidRuntime: FATAL EXCEPTION: main Process: com.omitneedlesscode.nodependency, PID: 13647 java.lang.NoSuchMethodError: No virtual method load(Ljava/lang/String;)Lcom/bumptech/glide/ DrawableTypeRequest; in class Lcom/bumptech/glide/RequestManager; or its super classes (declaration of 'com.bumptech.glide.RequestManager' appears in /data/app/com.omitneedlesscode.nodependency-m1gfBVcawag- PWVRV_wyZQ==/split_lib_dependencies_apk.apk) at com.omitneedlesscode.pugs.PugActivity.onCreate(PugActivity.kt:16) at android.app.Activity.performCreate(Activity.java:6975) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892) at android.app.ActivityThread.-wrap11(Unknown Source:0) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593) at android.os.Handler.dispatchMessage(Handler.java:105) at android.os.Looper.loop(Looper.java:164) at android.app.ActivityThread.main(ActivityThread.java:6541) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
136. 21:28:57.809 13647-13647/com.omitneedlesscode.nodependency E/AndroidRuntime: FATAL EXCEPTION: main Process: com.omitneedlesscode.nodependency, PID: 13647 java.lang.NoSuchMethodError: No virtual method load(Ljava/lang/String;)Lcom/bumptech/glide/ DrawableTypeRequest; in class Lcom/bumptech/glide/RequestManager; or its super classes (declaration of 'com.bumptech.glide.RequestManager' appears in /data/app/com.omitneedlesscode.nodependency-m1gfBVcawag- PWVRV_wyZQ==/split_lib_dependencies_apk.apk) at com.omitneedlesscode.pugs.PugActivity.onCreate(PugActivity.kt:16) at android.app.Activity.performCreate(Activity.java:6975) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892) at android.app.ActivityThread.-wrap11(Unknown Source:0) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593) at android.os.Handler.dispatchMessage(Handler.java:105) at android.os.Looper.loop(Looper.java:164) at android.app.ActivityThread.main(ActivityThread.java:6541) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
137. App Lib glide:3.8.0 glide:4.7.1
138. Do you really need that library?
139. Yes
140. But do you need it in your library?
141. Not necessarily
142. Command Pattern
143. Command Pattern Deferred Responsibility Pattern
144. Library interface AppUtilities { var imageFetcher: ImageFetcher }
145. Library interface ImageFetcher { fun loadImageInView(imageUrl: String, defaultImageResource: Int, view: ImageView) }
146. App class GlideImageFetcher: ImageFetcher { override fun loadImageInView(imageUrl: String, defaultImageResource: Int, view: ImageView) { GlideApp.with(view).load(imageUrl).placeholder(defaultImageResource).into(view) } }
147. App Lib glide:3.8.0 glide:4.7.1
148. Manifests
149. Content Providers
150. <provider android:grantUriPermissions="true" android:exported="false" android:authorities=“com.omitneedlesscode.fooprovider” android:name=".FooFileProvider"> <meta-data android:name="android.support.FILE_PROVIDER_PATHS" android:resource="@xml/filepaths" /> </provider>
151. <provider android:grantUriPermissions="true" android:exported="false" android:authorities=“com.omitneedlesscode.fooprovider” android:name=".FooFileProvider"> <meta-data android:name="android.support.FILE_PROVIDER_PATHS" android:resource="@xml/filepaths" /> </provider>
152. Providers have one authority
153. Android Manifest Placeholders
154. android { defaultConfig { manifestPlaceholders = [hostName:"www.example.com"] } ... }
155. <provider android:grantUriPermissions="true" android:exported="false" android:authorities="${applicationId}.fooprovider" android:name=".FooFileProvider"> <meta-data android:name="android.support.FILE_PROVIDER_PATHS" android:resource="@xml/filepaths" /> </provider>
156. Resources
157. Overriding IDs Lib App <string name="first_pug_name">Artoo</string> <string name="first_pug_name">R2</string>
158. Overriding IDs Lib App <string name="first_pug_name">Artoo</string> <string name="first_pug_name">R2</string>
159. Overriding IDs build variant build type product flavor main source set library dependencies
160. Overriding IDs build variant build type product flavor main source set library dependencies
161. –Someone “Why would I want to override resource IDs?”
162. App Specific Content
163. Overriding IDs Lib App <string name=“app_name”>Map My Ride</string> <string name=“app_name”>Map My Run</string>
164. Overriding IDs Strings Drawables Values Animations
165. Thanks! @echenger