disposeOnDestroy

DisposeOnDestroy.kt

import android.app.Activity
import android.app.Application
import android.os.Bundle
import io.reactivex.disposables.Disposable
import io.reactivex.functions.Consumer

fun Activity.disposeOnDestroy() = Consumer<Disposable> { disposable ->
    application.registerActivityLifecycleCallbacks(object : Application.ActivityLifecycleCallbacks {

        override fun onActivityDestroyed(activity: Activity) {
            if (this@disposeOnDestroy === activity) {
                application.unregisterActivityLifecycleCallbacks(this)
                disposable.dispose()
            }
        }

        override fun onActivityCreated(activity: Activity, savedInstanceState: Bundle?) = Unit
        override fun onActivityStarted(activity: Activity) = Unit
        override fun onActivityResumed(activity: Activity) = Unit
        override fun onActivityPaused(activity: Activity) = Unit
        override fun onActivityStopped(activity: Activity) = Unit
        override fun onActivitySaveInstanceState(activity: Activity, outState: Bundle) = Unit
    })
}