PubSubMessenger

PubSubMessenger is a Pub/Sub pattern library from ViewModel/Fragment to Activity/Fragment.

Overview

PubSubMessenger is a Pub/Sub pattern library.
- Messaging from ViewModel to Activity/Fragment. For example, Navigation, Dialog, SnackBar and so on.
- Messaging from Fragment to Activity/Fragment. For example, Fragment callback, DialogFragment callback.
PubSubMessenger is Lifecycle-aware like LiveData.
- You can subscribe to messages at least Lifecycle.State.STARTED.
- If you publish a message when lifecycle isn't at least STARTED, the message is suspend until at least STARTED.
- A message consumed automatically when you observed unlike LiveData, SingleLiveEvent and LiveData<Event>.
- You can subscribe to messages multiple times unlike LiveData and SingleLiveEvent.
- You cannot use to communication with another Activity. There is risk of losing the message because of killing Activity by OS.
PubSubMessenger restricts where you publish and where you subscribe for preventing chaos by like EventBus.
- You can publish in ViewModel or Fragment.
- You can subscribe in Activity or Fragment.

The message needs to implement PubSubMessage.

class SampleMessage(val param: String): PubSubMessage

You can call pubSubMessenger.publish(message) in ViewModel or Fragment.

pubSubMessenger.publish(SampleMessage("You can pass parameters via the message"))

You can call pubSubMessenger.subscribe<PubSubMessage> { } in Activity or Fragment.

pubSubMessenger.subscribe<SampleMessage> { message ->
    Log.d(TAG, "Receive $message")
}

repositories {
    mavenCentral()
}

dependencies {
    implementation 'com.wada811.pubsubmessenger:pubsubmessenger:x.y.z'
}

Licensed under the Apache License, Version 2.0