Menu
I tried initializing my LiveData object and it gives the error: "LiveData is abstract, It cannot be instantiated"
LiveData listLiveData = new LiveData<>();
247
LiveData is an observable data holder class. Unlike a regular observable, LiveData is lifecycle-aware, meaning it respects the lifecycle of other app components, such as activities, fragments, or services. This awareness ensures LiveData only updates app component observers that are in an active lifecycle state.
ViewModel : Provides data to the UI and acts as a communication center between the Repository and the UI. Hides the backend from the UI. ViewModel instances survive device configuration changes. LiveData : A data holder class that follows the observer pattern, which means that it can be observed.
This function is deprecated. This extension method is not required when using Kotlin 1.4.
No, It is not mandatory to use LiveData always inside ViewModel, it is just an observable pattern to inform the caller about updates in data.
In a ViewModel, you may want to use MutableLiveData instead.
E.g.:
class MyViewModel extends ViewModel {
private MutableLiveData<String> data = new MutableLiveData<>();
public LiveData<String> getData() {
return data;
}
public void loadData() {
// Do some stuff to load the data... then
data.setValue("new data"); // Or use data.postValue()
}
}
Or, in Kotlin:
class MyViewModel : ViewModel() {
private val _data = MutableLiveData<String>()
val data: LiveData<String> = _data
fun loadData() {
viewModelScope.launch {
val result = // ... execute some background tasks
_data.value = result
}
}
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
