observeAsState not working for list, in jetpack compose

user_9792097 0
Viewed 1996

I am trying to display a list of objects in a composable. for that i am having a viewmodel with below list variable

var allProviders: LiveData<MutableList<ServiceProvider>> = MutableLiveData(mutableListOf())

also, on view model init, i am calling an api to populate above list as:-

private fun getAllMerchantList() {
    getAllMerchants(object: RetrofitCallback {
        override fun onData(data: Any?) {
            //some logic here
            allProviders.value?.addAll(allProvidersLocal)
            Log.i("TAG", "ServiceProviders inside: ${allProviders.value?.size}")
        }

        override fun onFailed(ex: String?) {
            Log.i("TAG", "onFailed: ${ex.toString()}")
        }
    })
}

And, observing above, in composable, like:-

val viewModel: MainActivityViewModel = viewModel()
val allProviders by viewModel.allProviders.observeAsState()

but, above code is not working. Its always returning empty list in composable. But if i log through viewmodel function, i can see the data. How can i correct this?

android-viewmodel android-jetpack-compose observer-pattern
2 Answers

Use mutableStateListOf instead of LiveData in Compose

var allProviders by mutableStateListOf<ServiceProvider>()

Now use it as a regular list object. It will trigger recompositions. Also, as far as possible use MutableState type objects in Compose since they are built for it, and vice versa.

user_158808650

You can also use

val mutableStateFlod: MutableStateFlow<MutableList<ServiceProvider>> = MutableStateFlow(emptyList())

instead ov LiveData and all

collectAsState
user_44774810
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