PriceTextView | 简单方便的价格TextView

I wish the amount to increase by 1 every time the "+" is clicked.

But now when I click "+", it shows like this

Problem(A): increment is red in android:onClick="increment" /> in activity_main.xml

Problem(B): I know I should write something inside () of increment() and I have tried (1)increment(view: View?)=> red alert: parameter 'view' is never used shows up, but Problem (A) will be solved.

increment(view: View?) is modified from java codes.

For my app I need values which are parsed by jSoup from a website and then returned to the user using a notification, these values change ~ every minute, so to be up-todate with the values I set up a task using a handler, this works good when the app is in foreground, but as soon as the user goes to the homescreen the app will return multiple exceptions like e.g. java.net.UnknownHostException or java.net.SocketTimeoutException, in the code this happens when jSoup is connecting to the specified site, I already tried using Services and AsyncTasks instead of threads, but it was always the exact same problem, I also searched for people with similar experiences, but I guess my issue is quite specific.

This is the code for the handler:

Prehisrory

I have a list of stocks (some objects) from RoomDB. Each one of them have "symbol", "name", "price" and what's most important, "isFavourite" fields. I made a ViewPager2 with two Fragments containing RecyclerView (actually there are just two instances of one class StocksFragment - one for all stocks, one for only favourite stocks). Each stock in RecyclerView is connected to the repository through Obsrver (data changes => stock's ViewHolder changes). Also each ViewHolder has own checkBox that changes "isFavourite" Stock field through StockListViewModel that calls StockRepository, that works directly with roomDB (with kotlin coroutines - sth like fun getStocks(): LiveData> = runBlocking{ stockDao.getStocks() })

Problem

When i click the same checkBox several times in a relatively small amount of time, all RecyclerView's ViewHolders become unclickable (neither the delete button nor the checkbox works). But i still can scroll RecyclerView How can i fix that? I think i am doing something very inefficient but i dont know what.

Here is my StocksFragment code:

I created a shopping cart app, and it has a menu item. Then it has another activity called "SettingActivity", for this settingActivity will have a TextView to show "Primary language, secondary language and both language".

I got the SharedPreferences data in the SettingActivity. How can I pass those data to the MainAdapter?

Because when I click the secondary language in the SettingActivity, then the menu will change to secondary language or show both languages.

So, how can I get the SettingActivity's SharedPreference data in the MainAdapter?

SettingActivity: