This library holds a class to handle single live events in Android MVVM architectural pattern. This class is extended
form LiveData class, from androidx.lifecycle:lifecycle-extensions
library, to propagate the data as an event,
which means it emits data just once, not after configuration changes again. Note that event will only be sent
to active observers, any observers that started observing after the emit won't be notified of the event.
This source has a sample app where you can find LiveEventViewModel
in it, in which the LiveEvent
class is used as
follows.
class LiveEventViewModel : ViewModel() {
private val clickedState = LiveEvent<String>()
val state: LiveData<String> = clickedState
fun clicked() {
clickedState.value = ...
}
}
There are two behaviours of LiveEvent
in-demand. First one is LiveEventConfig.Normal
,
where supports multi-observers on all cases the same. This config was originally implemented for
this library so it's the default config, but if you want to be explicit, you can pass it to the
constructor of LiveEvent
.
The second config is LiveEventConfig.PreferFirstObserver
. This one is useful when you want to
emit an event in the init
method of ViewModel
and expect the first observer receive it.
To set it up you need to pass it to the constructor
private val clickedState = LiveEvent<String>(config = LiveEventConfig.PreferFirstObserver)
Download via gradle
implementation "com.github.hadilq:live-event:$libVersion"
where you can find the libVersion
in the Releases page of this repository.
Snapshots of the development version are available in Sonatype's snapshots repository.
Just create your branch from the master branch, change it, write additional tests, satisfy all tests, create your pull request, thank you, you're awesome.