我如何用Kodein注射?

时间:2019-04-18 11:08:18

标签: android kotlin kodein

我刚刚学习了用于依赖注入的kodein lib。我如何获取变量的依赖值? 我在下面的应用程序类中,在那里将上下文与kodein绑定:

class BaseApp : Application(), KodeinAware {
    override val kodein by Kodein.lazy {
        import(contextModule)
    }

    private val contextModule = Kodein.Module(CONTEXT_MODULE_TAG){
        bind<Context>(CONTEXT_TAG) with provider { this@BaseApp }
    }

    companion object{
        private const val CONTEXT_MODULE_TAG = "context_module"
        const val CONTEXT_TAG = "context_tag"
    }
}

在存储库类中,我尝试获取上下文,但没有成功。

class BatteryRepository : KodeinAware {
    override val kodein by kodein()
    private val context by instance<Context>(BaseApp.CONTEXT_TAG)
...

kodein()方法调用错误:

  

表达式“ kodein”不能作为函数调用。找不到函数“ invoke()”

我如何获得背景信息?像这样传递上下文是个好主意吗?

1 个答案:

答案 0 :(得分:0)

我有同样的问题。原来我缺少此依赖项import org.kodein.di.android.x.kodein(不确定为什么它没有被IDE自动添加)

以下是Kodein + AndroidX库的示例: AndroidManifest.xml

<application
        ...
        android:name=".core.BaseApplication">

应用

open class BaseApplication : Application(), KodeinAware {
    override val kodein = Kodein.lazy {
        import(androidXModule(this@BaseApplication))

        // import(otherCustomModule)
    }
}

片段

import androidx.fragment.app.Fragment
import org.kodein.di.Kodein
import org.kodein.di.KodeinAware
import org.kodein.di.android.x.kodein
import org.kodein.di.generic.kcontext

abstract class InjectionFragment : Fragment(), KodeinAware {

    final override val kodeinContext = kcontext<Fragment>(this)
    final override val kodein: Kodein by kodein()


    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        kodeinTrigger?.trigger()
    }
}

// usage
class MyFragment() : InjectionFragment() {
    val someDependency: Type by instance()
}

依赖项app\build.gradle

implementation "org.kodein.di:kodein-di-generic-jvm:6.3.2"
implementation "org.kodein.di:kodein-di-framework-android-x:6.3.2"
implementation "androidx.appcompat:appcompat:1.0.2"

额外 还值得重写kodeinTrigger属性(来自KodeinAware)。这样,创建Fragment时将解决debug构建的所有依赖关系,因此应用程序将立即失败(与release构建仅在使用依赖关系时才解决依赖关系相反-某些用户路径可能无法解析)使应用程序崩溃)

abstract class InjectionFragment : Fragment(), KodeinAware {

    final override val kodeinContext = kcontext<Fragment>(this)
    final override val kodein: Kodein by kodein()
    final override val kodeinTrigger: KodeinTrigger? // See description in InjectionActivity
        get() = if (BuildConfig.DEBUG) KodeinTrigger() else super.kodeinTrigger

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        kodeinTrigger?.trigger()
    }
}