Tiny simple EventBus simulating activity result-like behaviour!

allprojects {
    repositories {
        maven { url 'https://andob.io/repository/open_source' }
    }
}

dependencies {
    implementation 'ro.andob.activityresult:eventbus:2.0.8'
}

Example

You have two activities, MainActivity and CatListActivity containing a list of cats. MainActivity must open CatListActivity and receive the cat selected by the user from the list:

• Define the event class:

class OnCatChoosedEvent
(
    val cat : Cat
)

• Send the event in the CatListActivity context:

chooseCatButton.setOnClickListener {
    ActivityResultEventBus.post(OnCatChoosedEvent(cat))
    finish()
}

• Receive events back in the MainActivity context:

startActivity(Intent(context, CatListActivity::class.java))
onActivityResult<OnCatChoosedEvent> { event ->
    catLabel.text = event.cat.name
}

All events will be received on UI thread.

• Let all your activities extend AppCompatActivityWithActivityResultEventBus:

abstract class BaseActivity : AppCompatActivityWithActivityResultEventBus()

• You can also receive events anywhere else you want, fragments, views or other objects:

import ro.andreidobrescu.activityresulteventbus.onActivityResult

context.startActivity(Intent(context, CatListActivity::class.java))
onActivityResult<OnCatChoosedEvent>(context) { event ->
    catLabel.text = event.cat.name
}

Java-friendly API

All APIs available in this library are Java-friendly. Example usage in Java:

• Posting events:

catButton.setOnClickListener(v ->
{
    ActivityResultEventBus.post(new OnCatChoosedEvent(cat));
    finish();
});

• Receiving events in an activity:

startActivity(new Intent(getContext(), CatListActivity.class));
onActivityResult(OnCatChoosedEvent.class, event -> catLabel.setText(event.cat.name));

• Receiving events in a fragment / view / other object:

import static ro.andreidobrescu.activityresulteventbus.onActivityResult;

getContext().startActivity(new Intent(getContext(), CatListActivity.class));
onActivityResult(getContext(), OnCatChoosedEvent.class, event -> catLabel.setText(event.cat.name));

Permission asker

You can also use this library to ask runtime permissions:

if (!PermissionAsker.arePermissionsAccepted(context = this, arrayOf(Manifest.permission.CAMERA)))
{
    PermissionAsker.ask(context = this, arrayOf(Manifest.permission.CAMERA))
        .onGranted { doSomething() }
        .onDenied { doSomething() }
}

License

Copyright 2019-2021 Andrei Dobrescu

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.`