kotlin - 我可以在 Kotlin 中使用 is null 而不是 isInitialized 吗？

Question

以下代码A来自项目play-billing-samples .

我可以在 Kotlin 中使用 is null 而不是 isInitialized 吗？就像代码B一样

代码A

lateinit private var localCacheBillingClient: LocalBillingDb

val inappSkuDetailsListLiveData: LiveData<List<AugmentedSkuDetails>> by lazy {
    if (::localCacheBillingClient.isInitialized == false) {
          localCacheBillingClient = LocalBillingDb.getInstance(application)
    }
     ...
}

代码B

lateinit private var localCacheBillingClient: LocalBillingDb

val inappSkuDetailsListLiveData: LiveData<List<AugmentedSkuDetails>> by lazy {
    if (localCacheBillingClient == null) {
          localCacheBillingClient = LocalBillingDb.getInstance(application)
    }
    ...
}

Answer 1

是的，你可以，但你必须将变量的类型更改为 LocalBillingDb? 并去掉 lateinit 修饰符:

private var localCacheBillingClient: LocalBillingDb? = null 

val inappSkuDetailsListLiveData: LiveData<List<AugmentedSkuDetails>> by lazy {
    if (localCacheBillingClient == null) {
          localCacheBillingClient = LocalBillingDb.getInstance(application)
    }
    ...
}