Koinを使ってActivity/Fragment間で共有するViewModelをDIする

• build.gradle

buildscript {
    ext.kotlin_version = '1.4.10'
    ext.koin_version = '2.1.6'
    repositories {
        google()
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:4.0.2'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath "org.koin:koin-gradle-plugin:$koin_version"
    }
}

• app/build.gradle

dependencies {
    implementation "org.koin:koin-android:$koin_version"
    implementation "org.koin:koin-androidx-scope:$koin_version"
    implementation "org.koin:koin-androidx-viewmodel:$koin_version"
}

• MainActivity

class MainActivity : AppCompatActivity() {

    private val viewModel: MainViewModel by viewModel()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        supportFragmentManager.beginTransaction()
            .replace(R.id.content_layout, MainFragment())
            .commit()
    }
}

• MainFragment

class MainFragment : Fragment() {

    private val viewModel by sharedViewModel<MainViewModel>()

    ...
}