tipbuddy-compute.kt

fun computeTipAndTotal() {

        // 10 - Conditional check to fix java.lang.NumberFormatException: empty String crash,
        // when edit text is empty.
        if (billEditText.text.isEmpty()) {

            // 10b) Update values of tip and total to empty & return here
            tvTipAmount.text = "$INITIAL_EMPTY_VALUE"
            tvTotalAmount.text = "$INITIAL_EMPTY_VALUE"
            return // This ensures the logic in 7b isn't run. 👍
        }

        //7b) Get the value of the bill and tip percent
        // Once we have these values, we can calculate the amount for the tip, (tip% x bill)
        // We can also calculate the value for the total (tip + bill)
        // Bill value - value inside edit text
        // Call to string to change int to string. toDouble so that we can do math.
        val billAmount = billEditText.text.toString().toDouble()

        // Tip %age - The progress of the SeekBar
        val tipPercent = tipSeekBar.progress

        // Calculate the tip amount
        val tipAmount = billAmount * tipPercent / 100

        // Calculate total amount
        val totalAmount = billAmount + tipAmount

        // 8) NOTE: After the calculation, place the tipAmount and totalAmount, into
        // the respective textViews.
        tvTipAmount.text = "%.2f".format(tipAmount)
        tvTotalAmount.text = "%.2f".format(totalAmount)
    }