首页 > 解决方案 > Kodein 构造函数注入 Kodein$NotFoundException

问题描述

出于某种原因,我无法让构造函数注入与 Kodein 一起使用。

这是重现异常的代码:

import org.kodein.di.Kodein
import org.kodein.di.direct
import org.kodein.di.generic.bind
import org.kodein.di.generic.instance
import org.kodein.di.generic.provider

fun main(args: Array<String>) {
    val kodein = Kodein {
        bind<Test2>() to provider { Test2() }
        bind<Test>() to provider { Test(instance()) }
    }

    val test = kodein.direct.instance<Test>()
}

class Test(val test2: Test2)
class Test2

例外:

Exception in thread "main" org.kodein.di.Kodein$NotFoundException: No binding found for bind<Test>() with ? { ? }
Registered in this Kodein container:

    at org.kodein.di.internal.KodeinContainerImpl.factory(KodeinContainerImpl.kt:174)
    at org.kodein.di.KodeinContainer$DefaultImpls.factory$default(KodeinContainer.kt:33)
    at org.kodein.di.KodeinContainer$DefaultImpls.provider(KodeinContainer.kt:80)
    at org.kodein.di.internal.KodeinContainerImpl.provider(KodeinContainerImpl.kt:7)
    at org.kodein.di.KodeinContainer$DefaultImpls.provider$default(KodeinContainer.kt:79)
    at org.kodein.di.internal.DKodeinBaseImpl.Instance(DKodeinImpl.kt:33)
    at AppKt.main(App.kt:20)

为什么这不起作用?

标签: kotlinconstructor-injectionkodein

解决方案


bind<Test2>() to provider { Test2() }
              ^^

这是 Kotlin 的to函数,它生成一个Pair与 Kodein 的 DSL 无关的函数:p

Kodein 的 DSL 使用with

bind<Test2>() with provider { Test2() }
              ^^^^

请注意,当您将类型绑定到自身时,可以使用更简单的语法:

bind() from provider { Test2() }

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