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Android get ArrayList from Room Database in adapter class

I have a Room Database table with multiple columns (PartsTable). I need to fetch only one column from the table that contains one word String and I’m using a subset of a table as per google docs (PartsTuple).

Now I need to create a function that will or something else that will return the ArrayList of fetched data, which I can access in my adapter class. I am able to return the data and see it in a console log (from the main fragment where I get data from ViewModel), but I just can’t seem to make it work on a function that will return the said list of data which I could then access from a different class.

Code from DAO:

@Query("SELECT keyword FROM partsTable")
LiveData<List<PartsTuple>> getTuple();

Code from repo:

public LiveData<List<PartsTuple>> getPartsTuple() {
return partsKeyword;
}

Code from view model:

public LiveData<List<PartsTuple>> getPartsTuple() {
    return partsKeyword;
}

Fragment class where I display data in a log:

mViewModel.getPartsTuple().observe(getViewLifecycleOwner(), new Observer<List<PartsTuple>>() {
        @Override
        public void onChanged(List<PartsTuple> partTuple) {
            Log.d(TAG, "vraceno: " + partTuple.toString());
        }
    });

, and data from the log

D/PartsFragment: vraceno: [part1, parts3, part_2]

Code from adapter class where I compare strings and highlight them.

ArrayTEST arrayTEST = new ArrayTEST();
        ArrayList<String> values = arrayTEST.getWordFromHardcodedList();

        String text = note.getPartsSubtitle();
        Spannable textSpannable = new SpannableString(text);

        for (int j = 0; j < values.size(); j++) {
            //word of list
            String word = String.valueOf(values.get(j));
            //find index of words
            for (int i = -1; (i = text.indexOf(word, i + 1)) != -1; i++) {
                //find the length of word for set color
                int last = i + word.length();
                
                textSpannable.setSpan(new BackgroundColorSpan(Color.parseColor("#1a0cab8f")),
                        i, last, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
                textSpannable.setSpan(new ForegroundColorSpan(Color.RED),
                        i, last, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
            }
        }
        if (note.getPartsSubtitle().trim().isEmpty()) {
            tvTEXT.setVisibility(View.GONE);
        } else {
            tvTEXT.setText(textSpannable);
        }

The part that I’m having trouble with is this, where I need to get a list of data from database and not hardCoded like this

arrayTEST.getWordFromHardcodedList();

Now I need to access this list of data from my adapter class since if there is a match I wanna highlight the parts from the list of parts in my main recycler view where all the data is shown. I can do this when I type the list manually but it needs to be dynamic based on user input.

Thanks in advance

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Answer

Ended up using shared preferences with Gson.

In app gradle add

implementation 'com.google.code.gson:gson:2.8.6'

Save the data to SP in a fragment:

SharedPreferences sharedPreferences = requireActivity().getSharedPreferences("shared_preferences", MODE_PRIVATE);
            SharedPreferences.Editor editor = sharedPreferences.edit();

            Gson gson = new Gson();
            String json = gson.toJson(myListOfData);
            editor.putString("partsKEY", json);
            editor.apply();

Load the array in the adapter class:

SharedPreferences sharedPreferences = context.getSharedPreferences("shared_preferences", MODE_PRIVATE);
        Gson gson = new Gson();
        String json = sharedPreferences.getString("partsKEY", null);
        Type type = new TypeToken<ArrayList<NoteTupleTest>>() {
        }.getType();
        partsArrayList= gson.fromJson(json, type);
        if (partsArrayList== null) {
            partsArrayList= new ArrayList<>();
        }

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