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Use of adapter.notifyDataSetChanged()

I am very new to Android development. I am little confuse about the use of Adapter.notifyDataSetChanged() with ArrayAdapter and ListView. In my project, I am displaying all student in ListView with the help of an ArrayAdapter. The ArrayAdapter is getting the data (ArrayList) from local(Sqlite) database. further, the local database is getting the data from server whenever the server data is changed.
I created the adapter instance in onCreate() and I bound the Listview with it. Whenever the local database is changed, I am trying to refresh the ListView with notifyDataSetChanged() method but somehow its not working.

Kotlin clear an adapter

What is the best way to clear an adapter in Kotlin?
I was trying to clear a recyclerview and update the values.
I am using LoaderManager and I am kind of stuck in this state.

If you want update recyclerview after adding/removing data in your adapter use this code
If you use Arraylist to store the data objects then just clear your list and call notifyDataSetChanged.
dataList.clear()
recyclerView?.adapter?.notifyDataSetChanged()

Unable to display data on listview

I am having an issue with displaying the data on my list view that been extracted from Firebase Database. There are my codes:
I hope if any of you could help me debug this error!
Thanks lads.

As explained in this post, to update an ArrayAdapter, you need to call the notifyDataSetChanged() method after changing the contents of the ArrayList.

Is it better to fetch data from database and put into ArrayList before binding it to RecyclerView?

I want to populate RecyclerView using database. As currently there is no inbuilt adapter for populating RecyclerView using database, I have used CursorRecyclerAdapter by Shywim. I have created a sample App to test it and it worked fine. The feature I didn't liked is having an _id column in the resultset and calling swapCursor() on each database operation, mostly insert and delete. This goes same with ListView when using SimpleCursorAdapter. My query is what if I use ArrayList as the dataset instead of directly using the Cursor.
Benefits of doing this(my assumption) :
No more a need of _id column in the resultset.
Can fetch the data from database, put it into ArrayList and close the cursor.
No need of calling swapCursor() on each database operation as I can add/remove specify elements from the ArrayList and call notifyDataSetChanged()
I don't know the exact logic behind swapCursor() and notifyDataSetChanged(). So, can't decide which one is light-weight and efficient.
If someone has experienced this or done this before, please clear my doubts. Any corrections and suggestions are most welcome.

Using array list and custom adapter is better way for this as per my understanding.
See some scenarios below :
1) Cursor will close after each transaction so database will work smoothly.
2) As you can close cursor on operation done so it will never generate cursor not closed exception.
3) You can modify view of each row easily and manage custom adapter as per your choice.
There are many other reasons, but in short custom adapter is better then cursor adapter as per my understanding.

How to update CustomListView item in Android using Model where the model data is downloaded from internet?

I have a CustomListView in my android app. Each item consists of two pieces of text which are to be retrieved from an online SQL database. I'm using a Model class called ListModel and a custom adapter called CustomAdapter. I'm using an Asynctask to download the model data from the internet. But the problem is that, adding of a ListModel object to my ArrayList is not working when I do it in the onPostExecute method of my Asynctask. So, the listview is not getting updated. How do I display the Model items on my Custom List as soon as they get downloaded? Is there any way to do that?

This type of problems occures when adapter not properly notify after data downloaded. Notify your adapter in postExecute by notifyDataSetChanged () method

Generally this is because notifyDataSetChanged() isn't called on the arrayadapter. (but stacktraces/your code would be helpful)
In addition, this is a prime use of an in-memory SQLite database (if you plan on doing any custom queries)
Or a full on-disk SQLite DB if you want to cache data.
(Adding a content provider(by just surrounding the SqliteDB) would also be nice if you want to abstract away some more and provide observers, etc. )