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Android Sqlite and notifyChanged()

Can anyone help me in populating the values from database and show in listview using the notifychanged()

you do not need to refresh activity. after fetching data from database you update your ArrayList or something like that, and call notifiyDataSetChanged() and it is done.

RecyclerView and Adapter, which one should take care of Data Change?

In RecyclerViewFragment Class, there is MovieData, and the Adapter Class stores MovieData.getMovieList( ).
My question is, when Event Handler be triggered,
Add / Delete data directly in RecyclerViewFragment Class
Define add( ) / delete( ) function in Adapter Class and call adapter.add( ) / adapter.delete( ) in RecyclerViewFragment Class
Which way is the better design? Who has the responsibility to take care of data change?

I would suggest to have RecyclerViewFragment containing the data. And create an adapter passing the reference to the data. For example:
mAdapter = new CustomAdapter(mMovieData.getMovieList());
Then in the RecyclerViewFragment just perform the needed actions such as add / remove such as:
mMovieData.getMovieList().add(index);
Think this is the most common way todo it. You do not want to replicate the getMovieList data twice in adapter and RecyclerViewFragment. This will get confusing.

If data change is happening after adapter has been initialized, then it should be handled inside adapter. Adapter also has a nifty function notifyDataSetChanged() which will update item positions inside the adapter when data has changed.

The recyclerview is not concerned with the data, this is all handled by the adapter you have created to present the data. Have a look at the functions here to see what options you have in regard to data changes.

Adapter is the responsible class for filling a list with data ,for example if you have a list that need to be filled with data lets say SCORES then the adapter is the one responsible for filling these scores in the list. on the other side, RecyclerView is reposnsilbe for making the adapter fill it with more speed and effecieny, the recyclerView uses views that are previously used to display data by the adapter and place them in cache for later reuse to display the same type object so that it doesn't have to initialize a new object each time the adapter want to fill item in the list which make it faster.
and here is a link that might help you as well :
Hope my answer have helped you.

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. )

Editing ArrayLists in Android ListView

I have an ArrayAdapter that's using an ArrayList to display data in a ListView.
During the course of the activity, I sometimes need to edit the ArrayList by adding and deleting items.
Is there a difference if I call the add/delete functions on the actual ArrayAdapter vs. the underlying ArrayList? Which is better to use?

Use the adapter methods. This will automatically notify your adapter (and thus the bound list) that your data has changed.

Some times it is necessary (or at least more convenient) to modify the ArrayList (e.g., is a field of some other class, or it is being modified by other thread that does not know about the adapter).
In those cases, you will need to call adapter.notifyDataSetChanged()

AutoCompleteTextView, ArrayAdapter and notifyDataSetChanged()

I'm using an AutoCompleteTextView with an ArrayAdapter which works like supposed.
The problem is, that I have to change the Array with the Autocomplete-Values. Calling notifyDataSetChanged() doesn't help. No changes are shown.
Do you know something to get around this problem?

Do not modify the ArrayList and call notifyDataSetChanged() as it will have no effect on ArrayAdapters (implementation seems broken).
Use clear(), add(), insert(), and remove() directly on your ArrayAdapter instead of those methods on your ArrayList.

You need to add more details to the question but based on a guesstimate of you problem, I would say that there is some problem in the implementation.
notifyDataSetChanged() informs the view to reload the data. If the data set up methods in the ArrayAdapter reference an unchanged data entity, notifyDataSetChanged() will have not effect.
A custom adapter implementation that extends ArrayAdapter will generally have an internal data structure that is the source of data for the adapter and which will contain the AutoComplete values you require.