How to update Recyclerview data

Question

Created a list using Recyclerview. There was a problem. After writing data to the database, a new item appears only after restarting the application. Please explain how to make this list updated.

using this method I get data from the database

public List<CategoryList> getTodayItems() throws SQLException, ParseException { open(); categoriesList = new ArrayList<>(); String strSQL = "select category_name, category_photo, operat_date, operat_sum\n" + "from source, income, operations\n" + "where source._id = id_source and operations._id = id_of_transaction and operat_date LIKE '" + getCurrentDate() + "%'" + " order by operat_date DESC"; Cursor c = database.rawQuery(strSQL, null); if (c.moveToFirst()) { // определяем номера столбцов по имени в выборке int nameIndex = c.getColumnIndex(dbHelper.COLUMN_NAME); int photoIndex = c.getColumnIndex(dbHelper.COLUMN_PHOTO); int dateIndex = c.getColumnIndex(dbHelper.COLUMN_OPERAT_DATE); int sumIndex = c.getColumnIndex(dbHelper.COLUMN_OPERAT_SUM); do { categoriesList.add(new CategoryList(c.getString(nameIndex), c.getInt(photoIndex), "Мои деньги", String.valueOf(c.getInt(sumIndex)), String.valueOf(makeDate(String.valueOf(c.getLong(dateIndex)))))); // получаем значения по номерам столбцов Log.d(LOG_TAG, "NAME = " + c.getString(nameIndex) + " PHOTO = " + c.getInt(photoIndex) + " DATE = " + c.getInt(dateIndex) + " SUM = " + c.getInt(sumIndex)); } while (c.moveToNext()); } close(); return categoriesList; }

then I do this:

  categoriesListsToday = myDb.getTodayItems(); final CategoryListAdapter adapterList = new CategoryListAdapter(categoriesListsToday, new CategoryListAdapter.OnItemClickListener() { @Override public void onItemClick(CategoryList category) { // } }); rvList.setAdapter(adapterList);

@jangorussia, maybe I didn’t understand how to do it, for example, I add new information, add and need to exit go to the application to see the new added item, or go to another activation and re-enter the activation with Recyclerview, and I need to add immediately update your Recyclerview and see the new item
After updating the database, you need to add new elements to the list using list.addAll (elements), and then call adapter.notifyDataSetChanged () on the adapter, as jangorussia wrote above.
You have a line of code: myRecyclerView.setAdapter (myAdapter) ;.
In this line there is an instance of myAdapter, and in turn it has a method notifiDateSetChange () it inherits from abstract ancestors.
If you update the adapter, which is a wrapper for access to the data set, then you and the recuperator are redrawn, without recreating the activation with the recuperator
@AndroidAndroid, if I understood correctly, then when I click on the add button, am I doing something like this?
myDb.add(category, textView_sum, true); categoriesListsToday.clear(); categoriesListsToday.addAll(categoriesListsToday); adapterList.notifyDataSetChanged();

How to update Recyclerview data

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