Android 用Flow封装一个FlowBus

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我是靠谱客的博主满意含羞草，最近开发中收集的这篇文章主要介绍Android 用Flow封装一个FlowBus，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

用途

用安卓jetpack提供的flow封装一个事件总线。支持黏性非粘性等一系列事件。

对比

RxBus：不用引入RxJava库，安卓端即可
LiveData：LiveData不知道谁发明的封装事件总线，反射源码不说，LiveData就不是用来干这事的。
Flow：代码简洁，Android封装

代码（给个赞，不要伸手党）

import androidx.lifecycle.LifecycleOwner
import androidx.lifecycle.Observer
import androidx.lifecycle.asLiveData
import com.sweet.framework.eventbus.core.EmptyMessage
import kotlinx.coroutines.channels.BufferOverflow
import kotlinx.coroutines.flow.MutableSharedFlow
import java.util.concurrent.ConcurrentHashMap

object SweetFlowBus {
    private var events = ConcurrentHashMap<Any, MutableSharedFlow<Any>>()
    private var stickyEvents = ConcurrentHashMap<Any, MutableSharedFlow<Any>>()

    private fun <T> with(objectKey: Any): MutableSharedFlow<T> {
        if (!events.containsKey(objectKey)) {
            events[objectKey] = MutableSharedFlow(0, 1, BufferOverflow.DROP_OLDEST)
        }
        return events[objectKey] as MutableSharedFlow<T>
    }

    private fun <T> withSticky(objectKey: Any): MutableSharedFlow<T> {
        if (!stickyEvents.containsKey(objectKey)) {
            stickyEvents[objectKey] = MutableSharedFlow(1, 1, BufferOverflow.DROP_OLDEST)
        }
        return stickyEvents[objectKey] as MutableSharedFlow<T>
    }

    fun <T> observe(owner: LifecycleOwner, objectKey: Any, observer: Observer<T>) {
        return with<T>(objectKey).asLiveData().observe(owner, observer)
    }

    fun observe(owner: LifecycleOwner, objectKey: Any, observer: () -> Unit) {
        return with<EmptyMessage>(objectKey).asLiveData().observe(owner) {
            observer()
        }
    }

    fun <T> observeForever(objectKey: Any, observer: Observer<T>) {
        return with<T>(objectKey).asLiveData().observeForever(observer)
    }

    fun observeForever(objectKey: Any, observer: () -> Unit) {
        return with<EmptyMessage>(objectKey).asLiveData().observeForever {
            observer()
        }
    }

    fun <T> observeSticky(owner: LifecycleOwner, objectKey: Any, observer: Observer<T>) {
        return withSticky<T>(objectKey).asLiveData().observe(owner, observer)
    }

    fun observeSticky(owner: LifecycleOwner, objectKey: Any, observer: () -> Unit) {
        return withSticky<EmptyMessage>(objectKey).asLiveData().observe(owner) {
            observer()
        }
    }

    fun <T> observerStickyForever(objectKey: Any, observer: Observer<T>) {
        return withSticky<T>(objectKey).asLiveData().observeForever(observer)
    }

    fun observerStickyForever(objectKey: Any, observer: () -> Unit) {
        return withSticky<EmptyMessage>(objectKey).asLiveData().observeForever {
            observer()
        }
    }

    fun post(objectKey: Any) {
        with<EmptyMessage>(objectKey).tryEmit(EmptyMessage)
    }

    fun <T> post(objectKey: Any, objectValue: T) {
        with<T>(objectKey).tryEmit(objectValue)
    }

    fun postSticky(objectKey: Any) {
        withSticky<EmptyMessage>(objectKey).tryEmit(EmptyMessage)
    }

    fun <T> postSticky(objectKey: Any, objectValue: T) {
        withSticky<T>(objectKey).tryEmit(objectValue)
    }


}