calculate amount on quantity input

StockBuyActivity.kt

override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setupAppbar()

        val symbol = intent.getStringExtra(SYMBOL_KEY) ?: throw IllegalArgumentException()
        isSellForm = intent.getBooleanExtra(SELL_KEY, false)
        buyStockButton.setText(if (isSellForm) R.string.action_sell_stock else R.string.action_buy_stock)
        categoryStockViewModel.tags = symbol
        radioButtonByText = indexRadioButtonChildren()
        fetchContent()

        amountRadioGroup.setOnCheckedChangeListener { group: RadioGroup?, checkedId: Int ->
            onCheckedChange(group, checkedId)
        }
        amountEditText.addTextChangedListener {
            amountChanged(it.toString())
        }
        buyStockButton.setBlockingOnClickListener {
            buyStockClick()
        }

        viewModel.preOrderStockTransaction.observe(this, Observer { resource ->
            preOrderStockResource(resource)
        })
        amountEditText.addTextChangedListener {
            amountErrorTextView.text = ""
            val amount = it.toString().toDoubleOrNull()

            if (amount != null) {
                quantityEditText.setText(String.format("%.4f", (amount / askPrice)))
            } else {
                quantityEditText.setText("")
            }
        }
        quantityEditText.addTextChangedListener {
            quantityErrorTextView.text = ""
            //Hangs for some reason
            val quantity = it.toString().toDoubleOrNull()
            if (quantity != null) {
                println((quantity * askPrice))
                amountEditText.setText(String.format("%.4f", (quantity * askPrice)))
            } else {
                amountEditText.setText("")
            }
        }
        priceEditText.addTextChangedListener {
            priceErrorTextView.text = ""
        }
        orderTypeRadioGroup.setOnCheckedChangeListener { _: RadioGroup?, checkedId: Int ->
            orderTypeChanged(checkedId)
        }
        orderTypeChanged(R.id.marketOrderRadioButton)
    }

so this:

amountEditText.addTextChangedListener {
            amountErrorTextView.text = ""
            val amount = it.toString().toDoubleOrNull()

            if (amount != null) {
                quantityEditText.setText(String.format("%.4f", (amount / askPrice)))
            } else {
                quantityEditText.setText("")
            }
        }

changes to
amountEditText.addTextChangedListener(amountListener)
and so on.

heres what i got currently:

 val amountListener = object : TextWatcher{
        override fun afterTextChanged(p0: Editable?) {
            amountErrorTextView.text = ""
            val amount = p0.toString().toDoubleOrNull()
            // Obviuosly enters a recursive problem
//           quantityEditText.removeTextChangedListener(quantityListener)
            if (amount != null) {
                quantityEditText.setText(String.format("%.4f", (amount / askPrice)))
            } else {
                quantityEditText.setText("")
            }
        }

        override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {}

        override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {}
    }

    val quantityListener = object :  TextWatcher {
        override fun afterTextChanged(p0: Editable?) {
            quantityErrorTextView.text = ""

            val quantity = p0.toString().toDoubleOrNull()
            //remove listener
            amountEditText.removeTextChangedListener(amountListener)
            if (quantity != null) {
                println((quantity * askPrice))
                amountEditText.setText(String.format("%.4f", (quantity * askPrice)))
            } else {
                amountEditText.setText("")
            }
            //add listener
            amountEditText.addTextChangedListener(amountListener)
        }

        override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {}

        override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {}
    }




    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setupAppbar()

        val symbol = intent.getStringExtra(SYMBOL_KEY) ?: throw IllegalArgumentException()
        isSellForm = intent.getBooleanExtra(SELL_KEY, false)
        buyStockButton.setText(if (isSellForm) R.string.action_sell_stock else R.string.action_buy_stock)
        categoryStockViewModel.tags = symbol
        radioButtonByText = indexRadioButtonChildren()
        fetchContent()

        amountRadioGroup.setOnCheckedChangeListener { group: RadioGroup?, checkedId: Int ->
            onCheckedChange(group, checkedId)
        }
        amountEditText.addTextChangedListener {
            amountChanged(it.toString())
        }
        buyStockButton.setBlockingOnClickListener {
            buyStockClick()
        }

        viewModel.preOrderStockTransaction.observe(this, Observer { resource ->
            preOrderStockResource(resource)
        })


        amountEditText.addTextChangedListener(amountListener)
        quantityEditText.addTextChangedListener(quantityListener)

Remove this line:

amountEditText.addTextChangedListener {
amountChanged(it.toString())
}