Class for the runtime switch of localization

localizedActivity.kt

// Class for the runtime switch of localization
@SuppressLint("Registered")
open class LocalizedActivity : AppCompatActivity() {
    override fun attachBaseContext(newBase: Context) {
        super.attachBaseContext((updateBaseContextLocale(newBase)))
    }

    private fun updateBaseContextLocale(context: Context): Context {
        val language = PreferenceManager.getDefaultSharedPreferences(context).getString("languages", Locale.getDefault().language)
        val locale = Locale(language)
        Locale.setDefault(locale)

        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            updateResourcesLocale(context, locale)
        } else updateResourcesLocaleLegacy(context, locale)

    }

    // we want to override default behaviour of home button to make sure it is returning
    // to the previous state. We don't have complicated back navigation.
    override fun onOptionsItemSelected(item: MenuItem): Boolean {
        when (item.itemId) {
        // Respond to the action bar's Up/Home button
            android.R.id.home -> {
                finish()
                return true
            }
        }
        return super.onOptionsItemSelected(item)
    }

    @TargetApi(Build.VERSION_CODES.N)
    private fun updateResourcesLocale(context: Context, locale: Locale): Context {
        val configuration = context.resources.configuration
        configuration.setLocale(locale)
        return context.createConfigurationContext(configuration)
    }

    @Suppress("DEPRECATION")
    private fun updateResourcesLocaleLegacy(context: Context, locale: Locale): Context {
        val resources = context.resources
        val configuration = resources.configuration
        configuration.locale = locale
        resources.updateConfiguration(configuration, resources.displayMetrics)
        return context
    }
}