BillingClient.BillingClientStateListener.onBillingSetupFinished 被多次调用

Question

我尝试使用 Kotlin 协程为 BillingClient v.2.2.0 编写一个包装器：

package com.cantalk.photopose.billing

import android.app.Activity
import android.content.Context
import com.android.billingclient.api.*
import com.android.billingclient.api.BillingClient.*
import com.cantalk.photopose.util.Logger
import kotlinx.coroutines.CompletableDeferred
import kotlin.coroutines.resume
import kotlin.coroutines.resumeWithException
import kotlin.coroutines.suspendCoroutine

class BillingClientAsync(context: Context) {
    private val billingClient: BillingClient = setupBillingClient(context)
    private val pendingPurchaseFlows = HashMap<String, CompletableDeferred<Purchase>>()

    private fun setupBillingClient(context: Context): BillingClient {
        return newBuilder(context)
            .enablePendingPurchases()
            .setListener { billingResult, purchases ->
                if (billingResult.responseCode == BillingResponseCode.OK && purchases != null) {
                    for (purchase in purchases) {
                        val deferred = pendingPurchaseFlows.remove(purchase.sku)
                        deferred?.complete(purchase)
                    }
                } else {
                    val iterator = pendingPurchaseFlows.iterator()
                    while (iterator.hasNext()) {
                        val entry = iterator.next()
                        entry.value.completeExceptionally(BillingException(billingResult))
                        iterator.remove()
                    }
                }
            }
            .build()
    }

    suspend fun queryPurchases(): List<Purchase> {
        Logger.debug("query purchases")

        ensureConnected()
        val queryPurchases = billingClient.queryPurchases(SkuType.INAPP)
        if (queryPurchases.responseCode == BillingResponseCode.OK) {
            return queryPurchases.purchasesList
        } else {
            throw BillingException(queryPurchases.billingResult)
        }
    }

    suspend fun querySkuDetails(@SkuType type: String, skus: List<String>): List<SkuDetails> {
        Logger.debug("query sku details for", type)

        ensureConnected()
        return suspendCoroutine { continuation ->
            val params = SkuDetailsParams.newBuilder()
                .setType(type)
                .setSkusList(skus)
                .build()
            billingClient.querySkuDetailsAsync(params) { billingResult, skuDetailsList ->
                if (billingResult.responseCode == BillingResponseCode.OK) {
                    continuation.resume(skuDetailsList)
                } else {
                    continuation.resumeWithException(BillingException(billingResult))
                }
            }
        }
    }

    suspend fun purchase(activity: Activity, skuDetails: SkuDetails): Purchase {
        Logger.debug("purchase", skuDetails.sku)

        ensureConnected()
        val currentPurchaseFlow = CompletableDeferred<Purchase>()
            .also { pendingPurchaseFlows[skuDetails.sku] = it }
        val params = BillingFlowParams.newBuilder()
            .setSkuDetails(skuDetails)
            .build()
        billingClient.launchBillingFlow(activity, params)
        return currentPurchaseFlow.await()
    }

    suspend fun consume(purchase: Purchase): String {
        Logger.debug("consume", purchase.sku)

        ensureConnected()
        return suspendCoroutine { continuation ->
            val params = ConsumeParams.newBuilder()
                .setPurchaseToken(purchase.purchaseToken)
                .setDeveloperPayload("TBD")
                .build()
            billingClient.consumeAsync(params) { billingResult, purchaseToken ->
                if (billingResult.responseCode == BillingResponseCode.OK) {
                    continuation.resume(purchaseToken)
                } else {
                    continuation.resumeWithException(BillingException(billingResult))
                }
            }
        }
    }

    suspend fun acknowledgePurchase(purchase: Purchase) {
        Logger.debug("acknowledge", purchase.sku)

        ensureConnected()
        return suspendCoroutine { continuation ->
            val params = AcknowledgePurchaseParams.newBuilder()
                .setPurchaseToken(purchase.purchaseToken)
                .setDeveloperPayload("TBD")
                .build()
            billingClient.acknowledgePurchase(params) { billingResult ->
                if (billingResult.responseCode == BillingResponseCode.OK) {
                    continuation.resume(Unit)
                } else {
                    continuation.resumeWithException(BillingException(billingResult))
                }
            }
        }
    }

    private suspend fun ensureConnected() {
        if (!billingClient.isReady) {
            startConnection()
        }
    }

    private suspend fun startConnection() {
        Logger.debug("connect to billing service")

        return suspendCoroutine { continuation ->
            billingClient.startConnection(object : BillingClientStateListener {
                override fun onBillingSetupFinished(billingResult: BillingResult) {
                    if (billingResult.responseCode == BillingResponseCode.OK) {
                        continuation.resume(Unit)
                    } else {
                        // TODO: 3 Google Play In-app Billing API version is less than 3
                        continuation.resumeWithException(BillingException(billingResult))
                    }
                }

                override fun onBillingServiceDisconnected() = Unit
            })
        }
    }
}

如您所见，当我尝试查询购买或购买时，我确保客户已准备就绪。但是在生产中存在很多错误：

java.lang.IllegalStateException: 
  at kotlin.coroutines.SafeContinuation.resumeWith (SafeContinuation.java:2)
  at com.cantalk.photopose.billing.BillingClientAsync$startConnection$2$1.onBillingSetupFinished (BillingClientAsync.java:2)
  at com.android.billingclient.api.zzai.run (zzai.java:6)

我试图了解问题的原因，并知道如果BillingClientStateListener.onBillingSetupFinished将被多次调用，可能会出现异常IllegalStateException: Already resumed。我想知道这怎么可能，因为我每次startConnection调用都在创建新的侦听器？我无法在模拟器或我的测试设备上重现这个问题。任何人都可以解释我这里发生了什么以及如何解决它？

Answer 1

我一开始也尝试这样做，但理由不正确。onBillingSetupFinished()根据设计，可能会被多次调用。一旦您BillingClient.startConnection(BillingClientStateListener)使用回调进行调用，它就会在内部存储回调，并在连接断开/恢复时再次调用它。您不应该在其他调用中传递新对象BillingClient.startConnection(BillingClientStateListener)。

阅读以下文档onBillingServiceDisconnected()：

调用以通知与计费服务的连接已丢失。

注意：这不会删除计费服务连接本身 - 与服务的绑定将保持活动状态，并且当计费服务下次运行且设置完成时，您将收到对 onBillingSetupFinished(BillingResult) 的调用。

这意味着当连接断开然后重新恢复时，onBillingSetupFinished(BillingResult)将再次调用，并且在您的实现中，您将尝试再次恢复协程，但协程延续已经恢复，您将得到一个IllegalStateException.

我最终做的是BillingClientStateListener在类本身中实现接口，并且在回调中我SharedFlow<Int>用BillingResultfrom更新 aonBillingSetupFinished(BillingResult)

private val billingClientStatus = MutableSharedFlow<Int>(
    replay = 1,
    onBufferOverflow = BufferOverflow.DROP_OLDEST
)

override fun onBillingSetupFinished(result: BillingResult) {
    billingClientStatus.tryEmit(result.responseCode)
}

override fun onBillingServiceDisconnected() {
    billingClientStatus.tryEmit(BillingClient.BillingResponseCode.SERVICE_DISCONNECTED)
}

然后，您可以收集流量以获取 SKU 价格或处理待处理的购买（如果计费客户端已连接），或者实施重试逻辑（如果未连接）：

init {
    billingClientStatus.tryEmit(BillingClient.BillingResponseCode.SERVICE_DISCONNECTED)
    lifecycleOwner.lifecycleScope.launchWhenStarted {
        billingClientStatus.collect {
            when (it) {
                BillingClient.BillingResponseCode.OK -> with (billingClient) {
                    updateSkuPrices()
                    handlePurchases()
                }
                else -> billingClient.startConnection(this)
            }
        }
    }
}

如果您正在执行某些需要计费客户端连接的操作，您可以通过执行以下操作来等待它：

private suspend fun requireBillingClientSetup(): Boolean =
    withTimeoutOrNull(TIMEOUT_MILLIS) {
        billingClientStatus.first { it == BillingClient.BillingResponseCode.OK }
        true
    } ?: false

（请注意，我使用的SharedFlow<T>是 and 不是StateFlow<T>for billingClientStatus：原因是StateFlow<T>不支持发出连续的相等值）。

Answer 2

我的设置略有不同（我用布尔值回调），但这是我能想到的最好的。更多的是一种解决方法而不是真正的解释：

private suspend fun start(): Boolean = suspendCoroutine {
  billingClient.startConnection(object : BillingClientStateListener {
    var resumed = false;

    override fun onBillingSetupFinished(billingResult: BillingResult) {
      if (!resumed) {
        it.resume(billingResult.responseCode == BillingResponseCode.OK)
        resumed = true
      }
    }

    override fun onBillingServiceDisconnected() {
      Toast.makeText(context, R.string.pay_error, Toast.LENGTH_SHORT).show()
      Log.e(LOG_TAG, "Billing disconnected")
    }
  })
}

对于这是否是一个真正的、长期的解决方案，目前还没有定论。