A Multiplatform Triathlon

For several years now, that we’ve been trying to find new solutions on how we could develop a single project and run it on all platforms. We’ve been seeing all types of solutions: some are web-based, others require you to learn a new language, and others even may require that you pay a monthly fee to use. It also comes with the drawback that all your UI depends on the framework implementation. So, if there’s a native update you’ll need to wait until someone rewrites the widgets for you to update your app.

Kotlin multiplatform gives us a new solution. It focuses on sharing your business logic across all platforms, leaving the UI to be implemented natively. Since it’s Kotlin, you can take full advantage of its language features - concise, safe, etc. Moreover, if you’re coming from android you might already be familiarised with Kotlin and even if you’re an iOS developer you’ll see that it’s quite similar to Swift.

Join me on this triathlon and let’s go through Android, iOS, and Web in under 30 minutes.

Transcript

1. @cafonsomota
   Kotlin through Android, iOS and Web
   A Multiplatform Triathlon
   

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2. Android Dev Lead @WITSoftware
   Founder @GDGCoimbra and co-founder @Kotlin_Knights
   ✍ Author @rwenderlich and @opinioesonline
   Podcaster wannabe
   Loves travel, photography and running
   @cafonsomota
   

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3. MATERIALS
   speakerdeck.com/cmota/a-multiplatform-triathlon
   github.com/cmota/kmp-a-multiplatform-triathlon
   cmota.github.io/kmp-codelabs
   @cafonsomota
   

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4. @cafonsomota
   dev-reactions/commitstrip/unrealist-mobile-dev-dream
   

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5. 2008 2012 2018
   2013
   2011 2017
   2006 2010
   2009 2015
   * Kotlin Multiplatform
   *
   

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6. - Small learning curve for web developers
   - Smaller team
   - Typically half of the cost needed on native
   - Less time (working hours) to built
   (advantages)
   Cross-platform
   to test
   to fix issues (hopefully not framework specific )
   

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7. - Chained to the framework implementation of UI
   - new updates from the OS will take time to adopt
   - Performance is not the same
   - Some native code might need to be written
   - OS/ device features are dependent on the fw support
   - Dart (flutter) is not widely used language (for now)
   - Committed to one framework/ language
   (disadvantages)
   Cross-platform
   

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8. View Slide

9. what about Kotlin Multiplatform?
   

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10. shares application logic
    doesn’t share the application UI
    kotlin
    multiplatform
    

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11. - Chained to the framework implementation of UI
    - new updates from the OS will take time to adopt
    - Performance is not the same
    - Some native code might need to be written
    - OS/ device features are dependent on the fw support
    - Dart (flutter) is not widely used language (for now)
    - Committed to one framework/ language
    (disadvantages)
    Cross-platform
    

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12. - Chained to the framework implementation of UI
    - new updates from the OS will take time to adopt
    - Performance is not the same
    - Some native code might need to be written
    - OS/ device features are dependent on the fw support
    - Dart (flutter) is not widely used language (for now)
    - Committed to one framework/ language
    Cross-multiplatform
    UI is developed natively
    nope, UI is developed natively
    

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13. - Chained to the framework implementation of UI
    - new updates from the OS will take time to adopt
    - Performance is not the same
    - Some native code might need to be written
    - OS/ device features are dependent on the fw support
    - Dart (flutter) is not widely used language (for now)
    - Committed to one framework/ language
    Cross-multiplatform
    nope, UI is developed natively
    UI is developed natively
    always arguable, but you’re leaving UI to native, so…
    

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14. - Chained to the framework implementation of UI
    - new updates from the OS will take time to adopt
    - Performance is not the same
    - Some native code might need to be written
    - OS/ device features are dependent on the fw support
    - Dart (flutter) is not widely used language (for now)
    - Committed to one framework/ language
    Cross-multiplatform
    nope, UI is developed natively
    yes, the UI
    UI is developed natively
    always arguable, but you’re leaving UI to native, so…
    

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15. - Chained to the framework implementation of UI
    - new updates from the OS will take time to adopt
    - Performance is not the same
    - Some native code might need to be written
    - OS/ device features are dependent on the fw support
    - Dart (flutter) is not widely used language (for now)
    - Committed to one framework/ language
    Cross-multiplatform
    nope, UI is developed natively
    yes, the UI
    UI is developed natively
    you have direct access
    to them; although if on
    shared module it might
    give you extra effort
    always arguable, but you’re leaving UI to native, so…
    

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16. - Chained to the framework implementation of UI
    - new updates from the OS will take time to adopt
    - Performance is not the same
    - Some native code might need to be written
    - OS/ device features are dependent on the fw support
    - Dart (flutter) is not widely used language (for now)
    - Committed to one framework/ language
    Cross-multiplatform
    nope, UI is developed natively
    yes, the UI
    UI is developed natively
    kotlin, is one of the most
    trending languages nowadays,
    with strong community support
    always arguable, but you’re leaving UI to native, so…
    you have direct access
    to them; although if on
    shared module it might
    give you extra effort
    

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17. (advantages)
    - Language features
    - Kotlin first!
    - Low risk
    - You decide what’s worth to share across platforms
    - Interoperability
    - Consistency across platforms
    - Strong investment from JetBrains and community support
    Kotlin Multiplatform server web native
    android desktop
    jvmMain jsMain androidMain iosMain macosX64Main
    linuxX64Main
    mingwX64Main
    

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18. - It’s in alpha
    - Although we keep seeing new projects in production
    - Space was announced during Kotlin Conf 19 (web, desktop and mobile)
    (apps in production)
    Kotlin Multiplatform
    Space
    Adapted from: KotlinConf 2019: Opening Keynote by Andrey Breslav
    Full KMP
    Cash App
    Shares:
    business logic
    Yandex Maps
    Shares:
    business logic,
    wrappers for C++
    libraries
    PlanGrid Planboard
    Workspace
    Shares:
    business logic,
    sync logic,
    mgmnt offline data
    Shares:
    business logic,
    networking,
    offline caching lyrs
    Shares:
    business logic
    

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19. Kotlin Multiplatform
    

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20. K
    otlin multiplatform
    using kotlin in projects
    that target more than
    one platform
    

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21. network network
    parser parser
    model model
    presentation presentation
    model
    parser
    network
    view
    presentation
    view view
    presentation presentation
    web
    iOS
    android
    

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22. business logic business logic business logic
    model
    parser
    network
    presentation
    model
    parser
    network
    presentation
    model
    parser
    network
    presentation
    view view view
    web
    iOS
    android
    

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23. model
    parser
    network
    presentation
    common
    java/kotlin objective-c/ swift (kotlin) JS
    view view view
    web
    iOS
    android
    

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24. dev-reactions/it-works.gif
    

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25. View Slide

26. but how can different platforms
    expect to communicate?
    

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27. declared at common module
    expect
    declared at android module
    actual
    declared at iOS module
    declared at …
    

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28. in which platform is my application
    running?
    

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29. expect object Platform {
    
    val name: String
    
    }
    
    commonMain
    shared/src/commonMain/sample/Platform.kt
    

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30. expect object Platform {
    
    val name: String
    
    }
    
    shared/src/commonMain/sample/Platform.kt
    commonMain
    - define actual on android
    - define actual on iOS
    - define actual on web
    targets: android, iOS and the web
    

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31. import android.os.Build.MANUFACTURER
    
    actual object Platform {
    
    actual val name: String = $MANUFACTURER
    
    }
    
    shared/src/androidMain/sample/Platform.kt
    Platform-dependent code
    

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32. import android.os.Build.MANUFACTURER
    
    actual object Platform {
    
    actual val name: String = $MANUFACTURER
    
    }
    
    shared/src/androidMain/sample/Platform.kt
    Platform-dependent code
    

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33. import android.os.Build.MANUFACTURER
    
    actual object Platform {
    
    actual val name: String = $MANUFACTURER
    
    }
    
    shared/src/androidMain/sample/Platform.kt
    import platform.UIKit.UIDevice
    
    actual object Platform {
    
    actual val name: String = UIDevice.currentDevice().name
    
    }
    
    Platform-dependent code
    shared/src/iosMain/sample/Platform.kt
    

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34. import android.os.Build.MANUFACTURER
    
    actual object Platform {
    
    actual val name: String = $MANUFACTURER
    
    }
    
    shared/src/androidMain/sample/Platform.kt
    import platform.UIKit.UIDevice
    
    actual object Platform {
    
    actual val name: String = UIDevice.currentDevice().name
    
    }
    
    Platform-dependent code
    import kotlinx.browser.window
    
    actual object Platform {
    
    actual val name: String = window.navigator.useragent
    
    }
    
    shared/src/iosMain/sample/Platform.kt
    shared/src/jsMain/sample/Platform.kt
    

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35. Platform-dependent code
    Hello Google-Chrome
    Hello Pixel-XL Hello iOS-Simulator
    

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36. androidApp/
    iosApp/
    shared/
    web/
    

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37. androidApp/
    iosApp/
    shared/
    web/
    main/
    MainActivity.kt
    src/
    java/
    app.package.name/
    activities/
    

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38. src/
    commonMain/
    commonTest/
    shared/
    androidApp/
    iosApp/
    web/
    

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39. src/
    commonMain/
    commonTest/
    shared/
    
    androidApp/
    iosApp/
    web/
    

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40. androidMain
    androidTest
    
    src/
    commonMain/
    commonTest/
    shared/
    androidApp/
    iosApp/
    web/
    

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41. 
    
    src/
    commonMain/
    commonTest/
    shared/
    androidMain
    androidTest
    androidApp/
    iosApp/
    web/
    

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42. 
    
    src/
    commonMain/
    commonTest/
    shared/
    androidMain
    androidTest
    iosMain/
    iosTest/
    jsMain/
    jsTest/
    
    
    

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43. Let’s get everything
    together
    

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44. build.gradle.kts (:shared)
    kotlin {
    
    
    
    sourceSets {
    
    val commonMain by getting {
    
    dependencies {
    
    
    
    implementation("io.ktor:ktor-client-core:1.4.0")
    
    implementation("io.ktor:ktor-client-json:1.4.0")
    
    implementation("io.ktor:ktor-client-serialization:1.4.1")
    
    implementation("org.jetbrains.kotlinx:kotlinx-serialization-core:1.0.0")
    
    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.9")
    
    implementation("com.squareup.sqldelight:runtime:1.4.3")
    
    implementation("com.russhwolf:multiplatform-settings:0.6.2")
    
    }
    
    }
    
    }
    
    }
    

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45. build.gradle.kts (:shared)
    kotlin {
    
    android()
    
    
    
    sourceSets {
    
    val commonMain by getting {
    
    dependencies {
    
    
    
    implementation("io.ktor:ktor-client-core:1.4.0")
    
    implementation("io.ktor:ktor-client-json:1.4.0")
    
    implementation("io.ktor:ktor-client-serialization:1.4.1")
    
    implementation("org.jetbrains.kotlinx:kotlinx-serialization-core:1.0.0")
    
    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.9")
    
    implementation("com.squareup.sqldelight:runtime:1.4.3")
    
    implementation("com.russhwolf:multiplatform-settings:0.6.2")
    
    }
    
    val androidMain by getting {
    dependencies {
    implementation("androidx.preference:preference:1.1.1")
    implementation("io.ktor:ktor-client-android:1.4.0")
    implementation("io.ktor:ktor-client-okhttp:1.4.0")
    implementation("com.squareup.sqldelight:android-driver:1.4.3")
    }
    }
    }
    
    

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46. build.gradle.kts (:shared)
    kotlin {
    
    android()
    
    val onPhone = System.getenv("SDK_NAME")?.startsWith("iphoneos") ?: false
    if (onPhone) {
    iosArm64("ios")
    } else {
    iosX64("ios")
    }
    cocoapods {
    summary = "Some description for a Kotlin/Native module"
    homepage = "Link to a Kotlin/Native module homepage"
    frameworkName = "shared"
    ios.deploymentTarget = "13.2"
    }
    sourceSets {
    
    val commonMain by getting {
    
    dependencies {
    
    
    
    implementation("io.ktor:ktor-client-core:1.4.0")
    
    implementation("io.ktor:ktor-client-json:1.4.0")
    
    implementation("io.ktor:ktor-client-serialization:1.4.1")
    
    implementation("org.jetbrains.kotlinx:kotlinx-serialization-core:1.0.0")
    
    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.9")
    
    

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47. build.gradle.kts (:shared)
    kotlin {
    
    android()
    
    val onPhone = System.getenv("SDK_NAME")?.startsWith("iphoneos") ?: false
    if (onPhone) {
    iosArm64("ios")
    } else {
    iosX64("ios")
    }
    cocoapods {
    summary = "Some description for a Kotlin/Native module"
    homepage = "Link to a Kotlin/Native module homepage"
    frameworkName = "shared"
    ios.deploymentTarget = "13.2"
    }
    sourceSets {
    
    val commonMain by getting {
    
    dependencies {
    
    
    
    implementation("io.ktor:ktor-client-core:1.4.0")
    
    implementation("io.ktor:ktor-client-json:1.4.0")
    
    implementation("io.ktor:ktor-client-serialization:1.4.1")
    
    implementation("org.jetbrains.kotlinx:kotlinx-serialization-core:1.0.0")
    
    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.9")
    
    implementation("com.squareup.sqldelight:runtime:1.4.3")
    
    implementation("com.russhwolf:multiplatform-settings:0.6.2")
    
    }
    
    val androidMain by getting {
    dependencies {
    implementation("androidx.preference:preference:1.1.1")
    implementation("io.ktor:ktor-client-android:1.4.0")
    implementation("io.ktor:ktor-client-okhttp:1.4.0")
    implementation("com.squareup.sqldelight:android-driver:1.4.3")
    }
    }
    }
    
    val iosMain by getting {
    dependencies {
    implementation("io.ktor:ktor-client-ios:1.4.0")
    implementation("com.squareup.sqldelight:native-driver:1.4.3")
    }
    }
    }
    
    }
    

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48. build.gradle.kts (:shared)
    kotlin {
    
    android()
    
    val onPhone = System.getenv("SDK_NAME")?.startsWith("iphoneos") ?: false
    if (onPhone) {
    iosArm64("ios")
    } else {
    iosX64("ios")
    }
    cocoapods {
    summary = "Some description for a Kotlin/Native module"
    homepage = "Link to a Kotlin/Native module homepage"
    frameworkName = "shared"
    ios.deploymentTarget = "13.2"
    }
    js {
    browser {
    }
    }
    sourceSets {
    
    val commonMain by getting {
    
    dependencies {
    
    
    
    implementation("io.ktor:ktor-client-core:1.4.0")
    
    implementation("io.ktor:ktor-client-json:1.4.0")
    
    implementation("io.ktor:ktor-client-serialization:1.4.1")
    
    implementation("org.jetbrains.kotlinx:kotlinx-serialization-core:1.0.0")
    
    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.9")
    
    implementation("com.squareup.sqldelight:runtime:1.4.3")
    
    implementation("com.russhwolf:multiplatform-settings:0.6.2")
    
    }
    
    val androidMain by getting {
    dependencies {
    implementation("androidx.preference:preference:1.1.1")
    implementation("io.ktor:ktor-client-android:1.4.0")
    implementation("io.ktor:ktor-client-okhttp:1.4.0")
    implementation("com.squareup.sqldelight:android-driver:1.4.3")
    }
    }
    }
    
    val iosMain by getting {
    dependencies {
    implementation("io.ktor:ktor-client-ios:1.4.0")
    implementation("com.squareup.sqldelight:native-driver:1.4.3")
    }
    }
    val jsMain by getting {
    dependencies {
    implementation("io.ktor:ktor-client-js:1.4.0")
    }
    }
    }
    
    }
    

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49. *.kt
    common
    expect
    JVM
    actual
    *.kt, *.java, *.jar
    Native
    actual
    *.kt, *C, Swift, Framework
    JS
    actual
    *.kt, *.js, NPM
    

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50. dev-reactions/god-mode.gif
    

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51. View Slide

52. View Slide

53. View Slide

54. - User interface
    - RecyclerView and more (Android)
    - UITableViewController and more (iOS)
    - Depends on the framework used (web)
    - Network request
    - Parse response objects
    - Store on local database
    - Use system preferences
    Project structure
    

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55. android iOS
    Room CoreData
    Retrofit Alamofire
    GSON/ Moshi JSONSerialization
    MVP, MVVM, MVI MVVM, ELM
    RxJava RxSwift
    Tests Tests
    Activity UIViewController
    RecyclerView UITableView
    web
    There are a lot of
    different frameworks
    here…
    - redux
    - Fetch
    - json-api-serializer
    …
    

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56. SQLDelight
    ktor
    kotlinx.serialization
    MVP
    kotlinx.coroutines
    kotlin.test
    Activity UIViewController
    RecyclerView UITableView
    android iOS web
    
    

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57. multiplatform
    ktor
    SQLDelight
    model
    kotlinx.serialization
    GetConferences
    SQLDriver dispatcher
    view
    presenter
    Settings
    presenter
    

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58. multiplatform
    network
    database
    model
    parser
    domain
    platform specific
    view
    presenter
    presenter
    

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59. Network
    class ConferencesAPI() {
    
    private val client = HttpClient()
    
    suspend fun fetchConfs() = client.get("$URL")
    src/commonMain/data/ConferencesAPI.kt
    ktor
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    

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60. src/commonMain/domain/model/Conference.kt
    model
    @Serializable
    
    data class Conference (
    
    val name: String,
    
    val city: String,
    
    val country: String,
    
    val date: String,
    
    val logo: String,
    
    val website: String,
    
    val status: String)
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    

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61. domain
    class GetConferences(val api: ConferencesAPI) {
    
    suspend operator fun invoke(
    
    onSuccess: (List) "-> Unit,
    
    onFailure: (Exception) "-> Unit) {
    
    val result = api.fetchConfs()
    
    val confs = Json.decodeFromString>(result)
    
    coroutineScope {
    
    onSuccess(confs)
    
    }
    
    ""...
    }
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    src/commonMain/domain/GetConferences.kt
    

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62. domain
    class GetConferences(val api: ConferencesAPI) {
    
    suspend operator fun invoke(
    
    onSuccess: (List) "-> Unit,
    
    onFailure: (Exception) "-> Unit) {
    
    val result = api.fetchConfs()
    
    val confs = Json.decodeFromString>(result)
    
    coroutineScope {
    
    onSuccess(confs)
    
    }
    
    ""...
    }
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    src/commonMain/domain/GetConferences.kt
    

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63. domain
    class GetConferences(val api: ConferencesAPI) {
    
    suspend operator fun invoke(
    
    onSuccess: (List) "-> Unit,
    
    onFailure: (Exception) "-> Unit) {
    
    val result = api.fetchConfs()
    
    val confs = Json.decodeFromString>(result)
    
    coroutineScope {
    
    onSuccess(confs)
    
    }
    
    ""...
    }
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    src/commonMain/domain/GetConferences.kt
    

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64. domain
    class GetConferences(val api: ConferencesAPI) {
    
    suspend operator fun invoke(
    
    onSuccess: (List) "-> Unit,
    
    onFailure: (Exception) "-> Unit) {
    
    val result = api.fetchConfs()
    
    val confs = Json.decodeFromString>(result)
    
    coroutineScope {
    
    onSuccess(confs)
    
    }
    
    ""...
    }
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    src/commonMain/domain/GetConferences.kt
    

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65. src/commonMain/presentation/ConfsListPresenter.kt
    class ConfsListPresenter(val conferences: GetConferences) {
    
    lateinit var view: IConferenceData
    
    fun attachView(currView: IConferenceData) {
    
    view = currView
    
    fetchConfsList()
    
    }
    
    …
    
    
    
    presenter
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    

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66. src/commonMain/presentation/ConfsListPresenter.kt
    class ConfsListPresenter(val conferences: GetConferences) {
    
    lateinit var view: IConferenceData
    
    fun attachView(currView: IConferenceData) {
    
    view = currView
    
    fetchConfsList()
    
    }
    
    …
    
    
    
    presenter
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    

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67. src/commonMain/presentation/cb/IConferenceData.kt
    interface IConferenceData {
    
    fun onConferenceDataFetched(confs: List)
    
    fun onConferenceDataFailed(e: Exception)
    
    }
    presenter
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    

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68. src/commonMain/presentation/ConfsListPresenter.kt
    class ConfsListPresenter(val conferences: GetConferences) {
    
    lateinit var view: IConferenceData
    
    fun attachView(currView: IConferenceData) {
    
    view = currView
    
    fetchConfsList()
    
    }
    
    private fun fetchConfsList() {
    
    PresenterCoroutineScope(coroutineContext).launch {
    
    conferences(
    
    onSuccess = { view"?.onConferenceDataFetched(it) },
    
    onFailure = { view"?.onConferenceDataFailed(it) })
    
    presenter
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    

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69. object ServiceLocator {
    
    private val conferenceAPI by lazy {
    
    ConferencesAPI()
    
    }
    
    private val getConferences: GetConferences
    
    get() = GetConferences(conferenceAPI)
    
    val getConfsPresenter: ConfsListPresenter
    
    get() = ConfsListPresenter(getConferences)
    
    …
    
    presenter
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    src/commonMain/ServiceLocator.kt
    

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70. object ServiceLocator {
    
    private val conferenceAPI by lazy {
    
    ConferencesAPI()
    
    }
    
    private val getConferences: GetConferences
    
    get() = GetConferences(conferenceAPI)
    
    val getConfsPresenter: ConfsListPresenter
    
    get() = ConfsListPresenter(getConferences)
    
    …
    
    presenter
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    src/commonMain/ServiceLocator.kt
    

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71. src/commonAndroid/presenter/activities/MainActivity.kt
    android
    class MainActivity : AppCompatActivity(), IConferencesData {
    
    val presenter by lazy { ServiceLocator.getConfsPresenter }
    
    override fun onCreate(savedInstanceState: Bundle?) {
    
    super.onCreate(savedInstanceState)
    
    setContentView(R.layout.activity_main)
    
    presenter.attachView(this)
    
    }
    
    override fun onConferenceDataFetched(list: List){
    
    setup(list)
    
    …
    
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    

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72. src/commonAndroid/presenter/activities/MainActivity.kt
    android
    class MainActivity : AppCompatActivity(), IConferencesData {
    
    val presenter by lazy { ServiceLocator.getConfsPresenter }
    
    override fun onCreate(savedInstanceState: Bundle?) {
    
    super.onCreate(savedInstanceState)
    
    setContentView(R.layout.activity_main)
    
    presenter.attachView(this)
    
    }
    
    override fun onConferenceDataFetched(list: List){
    
    setup(list)
    
    …
    
    multiplatform
    network
    database
    android
    parser
    view
    platform
    specific
    presenter
    presenter
    domain
    model
    

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73. @cafonsomota
    > Configure project :shared
    
    Kotlin Multiplatform Projects are an Alpha feature.
    cmota.github.io/kmp-codelabs
    

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74. - Start small, don’t try to reach 100% of shared logic
    - perhaps by writing common tests to gain familiarity
    - one module at a time (network, database, image processing, etc.)
    - You can spend some time resolving compilation issues
    - specially if you try to target all platforms
    (how to start?)
    Kotlin Multiplatform
    - It’s in alpha
    - Lookout for plugins/ libraries updates
    

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75. - evangelize the iOS team
    - select one module where something is more complex on iOS than on Android
    - KMP is not intended to share the UI
    - iOS developers can focus on Swift and frontend features
    - Cross platform solutions like Flutter or React Native they need to use Dart or JS
    - not possible to debug kotlin from Xcode
    - plugin for Xcode from TouchLab/ support mentioned on Kotlin Conf 19
    (how to start?)
    Kotlin Multiplatform
    

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76. - Strong community
    - A lot of people are using kotlin nowadays
    - Google and JetBrains are pushing Kotlin in
    - You can ask questions directly on https://kotlinlang.slack.com
    - 2x faster to develop your features business logic
    - 2x faster writing unit tests
    - One tech stack
    - Consistency across platforms
    (conclusions)
    Kotlin Multiplatform
    

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77. - Ktor (networking)
    - Kotlinx.Coroutines
    - Kotlinx.Serialization
    - SqlDelight (database)
    - Multiplatform Settings
    - Stately (state management)
    (libraries)
    More information
    

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78. - .../JetBrains/kotlinconf-app
    - .../touchlab/DroidconKotlin
    - …/touchlab/KaMPKit
    - .../wojtek-kalicinski/sudoku-android
    - .../joreilly/PeopleInSpace
    - .../jonnyzzz/kotlin-game-of-life
    - .../MarcinMoskala/WorkoutMPP
    (cool projects to follow at GitHub)
    More information
    

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79. - Kotlin Slack
    - Kotlin by:
    https://jakewharton.com/presentations/
    https://touchlab.co/kamp-kit-touchlab/
    https://kmp.icerock.dev/
    - Kotlin Conf 2019 videos
    https://www.youtube.com/watch?v=0xKTM0A8gdI
    - Kotlin 1.4 Online Event
    https://www.youtube.com/watch?v=PW-jkOLucjM
    https://www.youtube.com/watch?v=5QPPZV04-50
    https://www.youtube.com/watch?v=KObxmllDzPY
    (useful links)
    More information
    

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80. @cafonsomota
    cmota.github.io/kmp-codelabs/
    cmota.github.io/kmp-codelabs
    

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81. @cafonsomota
    speakerdeck.com/cmota/a-multiplatform-triathlon
    github.com/cmota/kmp-a-multiplatform-triathlon
    cmota.github.io/kmp-codelabs
    

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