Android5.0以下のMultiDexで起動するシルクのように滑らか

android {
    defaultConfig {
        ...
        minSdkVersion 21 
        targetSdkVersion 26
        multiDexEnabled true //           ,     
    }
    ...
}

public class MyApplication extends SomeOtherApplication {
    @Override
    protected void attachBaseContext(Context base) {
        super.attachBaseContext(context);
        Multidex.install(this);
    }
}

override fun attachBaseContext(base: Context?) {
    super.attachBaseContext(base)
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP && TextUtils.equals(applicationContext?.packageName, processName)) {
        val multiDexPreference = getSharedPreferences("MultiDexPreference", Context.MODE_PRIVATE)
        if (multiDexPreference.getString(BuildConfig.VERSION_NAME, "") != the2thDexSHA1) {//     multiDex
            val lock = java.lang.Object()
            thread {
                Looper.prepare()
                val handler = object : Handler(Looper.myLooper()) {
                    override fun handleMessage(msg: Message?) {
                        super.handleMessage(msg)
                        synchronized(lock) {
                            lock.notify()
                            multiDexPreference.edit().putString(BuildConfig.VERSION_NAME, the2thDexSHA1).apply()
                            if (null != Looper.myLooper()) Looper.myLooper().quit()
                        }
                    }
                }
                startService( //        multiDex
                        Intent(applicationContext, MultiDexService::class.java)
                                .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
                                .putExtra("MESSENGER", Messenger(handler))
                )
                Looper.loop()
            }
            synchronized(lock) {
                try {
                    lock.wait(30000)
                } catch (e: InterruptedException) {
                    e.printStackTrace()
                }
            }
        }
    }
    if (!processName.endsWith("multiDex")) {
        //   Android5.0     ,                 MultiDex ,            
        MultiDex.install(this)
    }
}

private val the2thDexSHA1: String? by lazy {
    val ai = applicationInfo
    val source = ai?.sourceDir
    try {
        val jar = JarFile(source)
        val mf = jar.manifest
        val map = mf.entries
        val a = map["classes2.dex"]
        a?.getValue("SHA1-Digest").toString()
    } catch (e: Exception) {
        e.printStackTrace()
    }
    null
}

class MultiDexService : IntentService("MultiDexService") {
    override fun onHandleIntent(intent: Intent?) {
        val messenger: Messenger? = intent?.getParcelableExtra("MESSENGER")
        MultiDex.install(application)
        messenger?.send(Message())
        android.os.Process.killProcess(android.os.Process.myPid())

    }
}