RecyclerView not updated after fetching data from Room Database

Question

In my application I am fetching data from an api and saving it in Room Database. Fetching data from api and showing it directly in adapter is working fine.

But in case of no internet connection I am fetching data from database using coroutines. Problem here is I get the data successfully from database but it's not getting updated in the adapter. I tried calling notifyDataSetChanged after fetching data but still it's not showing anything on UI.

Also I have noticed a weird thing is that if I run the app in debug mode and go through all the code , it does shows list in the adapter when debugging is stopped .

Below is the code for fetching data from database and adding it in adapter.

override fun onActivityCreated(savedInstanceState: Bundle?) {
    super.onActivityCreated(savedInstanceState)
    if (isInternetAvailable()) {
        if (jobsList.size == 0) {
            getJobs()
        }
    }else{
        GlobalScope.launch {
            jobsList.addAll(dataBaHelperImpl.getJobs())
        }
        jobsViewModel.setJobsList(jobsList)

    }
}

ViewModel setJobList method

fun setJobsList(orderList: ArrayList<Jobs>){
    jobsAdapter.setItems(orderList)
    jobsAdapter.notifyDataSetChanged()

}

`dataBaHelperImpl.getJobs()` can be moved to viewmodel and use viewmodelScope there. Are you using livedata or flow for room?. You can observe the livedata in fragment — Raghunandan, Feb 27 '21 at 07:51
wathcing this https://www.youtube.com/watch?v=B8ppnjGPAGE should help. — Raghunandan, Feb 27 '21 at 08:03

score 2 · Answer 1 · answered Feb 27 '21 at 08:08

GlobalScope.launch is not a blocking call So you need to wait for it to finish then you can call jobsViewModel.setJobsList(jobsList) .

You should not be using Global Scope.

There r bunch of ways to fix this one is, You can move this call to ViewModel and use viewModelScope.launch directly and listen to a LiveData since android room internally supports co routine u do not have to provide a IO dispatcher. Something like below .

val jobLiveData=MutableLiveData<List<Jobs>>()
fun getJobs() {
    viewModelScope.launch {
        jobLiveData.value= dataBaHelperImpl.getJobs()
    }
}

RecyclerView not updated after fetching data from Room Database

1 Answers1