How to input a decimal number in a textEdit

Question

I have a TextEdit that has the input type of numberDecimal and I executes some code with inputted number

when I enter a whole number it works fine but when I enter a number with a decimal point the app completely restarts

So how would I make it work with a decimal number?

if you do end up helping me thank you in advanced

KT file

    class f_to_c : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.f_to_c)

        val actionBar = supportActionBar

        val calculate = findViewById<Button>(R.id.calculate)
        val tempEntered = findViewById<TextView>(R.id.tempEntered)
        val result = findViewById<TextView>(R.id.result)
        val temp = findViewById<EditText>(R.id.temp)


        if (actionBar != null){
            actionBar.title = "Fahrenheit To Celsius"
            actionBar.setDisplayHomeAsUpEnabled(true)
        }

        calculate.setOnClickListener {
            var x = Integer.parseInt(temp.getText().toString()).toString().toInt()
            tempEntered.text = x.toDouble().toString()
            result.text = ((x-32).toFloat()*5/9).toString()
        }

    }
}

Tyler V · Accepted Answer · 2021-12-23T02:39:37.153

If you want to handle decimal numbers, you shouldn't use Integer.parseInt. That will throw an error on something like "1.23". The following should work (or you could use Double.parseDouble)

val x = temp.getText().toString().toDoubleOrNull() ?: 0.0
tempEntered.text = x.toString()
result.text = ((x-32.0)*5.0/9.0).toString()

You may want to handle the null case differently in case the user enters an invalid number like "1..3", but this would just default to 0 in that case instead of throwing.

Also, if this is to be used internationally, you should consider that some locales use a comma for a decimal separator ("1,23") - which will break here. You could either use a locale-aware number parser for that, or just replace commas with periods before converting.

val xs = temp.getText().toString().replace(",",".")
val x = xs.toDoubleOrNull() ?: 0.0

How to input a decimal number in a textEdit

1 Answers1