ArchData

ArchData provides two missing LiveData of Android Lifecycle Component and useful extension functions.

MutableLiveData shares only last state to its new observers when they start to observe.

But in some cases, either these observers may want to do fresh start or they want to get all previous states.

PublishLiveData and ReplayLiveData types are extensions of MutableLiveData.

Basically:

• PublishLiveData is MutableLiveData, which only notify its observers if there is an event after their starting of observation.
• ReplayLiveData is MutableLiveData, which only notify its observers for all previous events happened before their observation starts.

Extension Functions:

• nonNullObserve is extension function, which eliminates nullable invokes of Observer.

LiveDataAction:

• LiveDataAction is special object type for LiveData,which enables observer can listen LiveData object without parameter. It is useful when Action/Command use cases.

Usage

• PublishLiveData

  LiveData that, once an Observer has subscribed, emits all subsequently observed items to the subscriber.

  val liveData = PublishLiveData<String>();
  // observer1 will receive all events
  liveData.observe(lifeCycleOwner,observer1)
  liveData.postValue("one")
  liveData.postValue("two")
  // observer2 will only receive "three"
  liveData.observe(lifeCycleOwner,observer2)
  liveData.postValue("three")
  

• ReplayLiveData

  LiveData that buffers all items it observes and replays them to any Observer that subscribes.

  val liveData =  ReplayLiveData<String>()
  liveData.postValue("one")
  liveData.postValue("two")
  liveData.postValue("three")
  // both of the following will get the events from above
  liveData.observe(lifeCycleOwner,observer1)
  liveData.postValue(lifeCycleOwner,observer2)
  

• nonNullObserve

  observe method which eliminates nullable invocation of observers.

  
  val liveData = MutableLiveData<String>()
  ...
  
  viewModel.liveData.nonNullObserve(lifeCycleOwner,::onLiveDataEvent)
  
  ...
  
  fun onLiveDataEvent(event: String){
     //Do something good!.
  }
  
  

• LiveDataAction

  Object Type which enables invocation listener methods without parameter

  
  val liveData = MutableLiveData<LiveDataAction>()
  ...
  
  viewModel.liveData.nonNullObserve(lifeCycleOwner,::onLiveDataAction)
  
  ...
  
  fun onLiveDataEvent(){
     //Do something really good!.
  }
  
  

Download

Maven:

<dependency>
  <groupId>me.ibrahimyilmaz</groupId>
  <artifactId>ArchData</artifactId>
  <version>0.0.4</version>
  <type>pom</type>
</dependency>

Gradle:

compile 'me.ibrahimyilmaz:ArchData:0.0.4'

License

MIT License

Copyright (c) [2019] [IBRAHIM YILMAZ | [email protected]]

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.