LocoLaser - Localization tool that generate localization files for various platforms depends on common source.
This example shows how to use LocoLaser in Kotlin Mobile Multiplatform projects to generate localized strings repository class with common interface for both mobile platforms: Android and iOS.

Example uses standard way to apply custom gradle plugin.
In build.gradle of the project was added maven repository and classpath:

buildscript {
  repositories {
    maven {
      // 1.1: Add maven repository
      url "https://plugins.gradle.org/m2/"
    }
    
    ...
  }
  dependencies {
    // 1.2: Add classpath dependency
    classpath "gradle.plugin.ru.pocketbyte.locolaser:plugin:1.0.4"
    
    ...
  }
}

Apply plugin in build.gradle of common module:

// 1.3: Apply LocoLaser plugin
apply plugin: "ru.pocketbyte.locolaser"

Choose which type of artifact you will use and add them as localize dependency. This example uses artifact to work with Kotlin Mobile Multiplatform projects:

dependencies {
    // 2.1: Add dependency for Kotlin mobile platforms
    localize "ru.pocketbyte.locolaser:platform-kotlin-mpp:1.3.0"
    // 2.2: Add dependency for JSON platform (for JS i18next)
    localize "ru.pocketbyte.locolaser:platform-json:1.3.0"
    
    ...
}

How to build config file you can find in Wiki: Platform: Kotlin Mobile Multiplatform By default this config file should have name"localize_config.json" and be placed in the root folder of the project.

This example run :localize task before each build. To do it add task dependencies in build.gradle of common module:

// 4 Run task ‘localize’ before each build
preBuild.dependsOn {
    project.tasks.getByPath(':common:localize')
}

As a final step instance of Strings repository should be created. This example use common object Repository with ‘expect’ modifier. This object should be implemented for each platform independently. In Android application it's better to implement standard singleton and initialize it in Application class in method onCreate:

// 5.1 Init Android Repository
Repository.initInstance(AndroidStringRepository(this))

In iOS application it's better to initialize property right in property declaration

JS implementation require i18next object as parameter So at first first add dependency with externals into common build.gradle:

kotlin {
    sourceSets {
        jsMain {
            // 5.2 Add i18next dependency
            dependencies {
                api "ru.pocketbyte.locolaser:i18next-externals:1.0"
            }
        }
    }
}

Then you should initialize it before use:

i18next.init(localizationConfig) { _, _ ->
    // 5.3 Init JS Repository
    Repository.init(JsStringRepository(i18next))
    ...
}

Now any string can be received using code as following:

Repository.str.screen_main_hello_text

Current version of Kotlin/Native doesn't support variadic Objective-C methods (see issue JetBrains/kotlin-native#1834). But this feature needs to implement plurals in iOS and macOS. If you want to use plurals, you should implement some workaround to make it work on iOS and macOS.

At first add LocalizedPlural.def into [common module]/src/iosMain/c_interop/.

Then add interop into build.gradle:

kotlin {
    targets {
        ...
    
        fromPreset(iOSTarget, 'ios') {
            // 6.2 Add interop to Objective-C code that implements work work with plurals
            compilations.main.cinterops{
                LocalizedPlural {
                    defFile project.file("src/iosMain/c_interop/LocalizedPlural.def")
                }
            }
            
            ...
        }
        ...
    }
}

Thats all. Now you able to use plurals on iOS/macOS. Any plural string can be received using code as following:

val count = 10
Repository.str.screen_main_plural_string(count)

Because String Repository classes generated depends on string resources, no need to hold them together with other source classes and commit into git. This example overrides res_dir of kotlin classes and put them into folders ./build/generated/locolaser/[platform]. To tell gradle plugin about this files, add source dirs into gradle.build of common module:

kotlin {
    sourceSets {
        commonMain {
            // 7.1 Add source dir for generated common classes
            kotlin.srcDir('./build/generated/locolaser/common/')
            
            ...
        }

        androidMain {
            // 7.2 Add source dir for generated android classes
            kotlin.srcDir('./build/generated/locolaser/android/')
            
            ...
        }

        jsMain {
            // 7.3 Add source dir for generated js classes
            kotlin.srcDir('./build/generated/locolaser/js/')

            ...
        }

        iosMain {
            // 7.4 Add source dir for generated iOS classes
            kotlin.srcDir('./build/generated/locolaser/ios/')
            
            ...
        }
    }
    ...
}

Copyright © 2019 Denis Shurygin. All rights reserved.
Contacts: <[email protected]>

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

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distributed under the License is distributed on an "AS IS" BASIS,
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