Android App crashes when pressing a Button in Kotlin

Question

I switched from Java to Kotlin and I am completely new. I tried to make an app that calculates your age to minute. The age input is through EditText in Android Studio. Then to set your age into TextView.

When I press on the button that application crashes. Below is the Kotlin Code


        var edtTxtAge = findViewById<EditText>(R.id.edtTxtAge)
        val btnCalc = findViewById<Button>(R.id.btnCalc)
        var txtAge = findViewById<TextView>(R.id.txtAge)

        btnCalc.setOnClickListener(View.OnClickListener {

            val minutesPerYear = 525600
            val age = edtTxtAge.toString().toInt() * minutesPerYear
            txtAge.text = "Your age in minutes is: " + age.toString()

        })

`val age = edtTxtAge.text.toString().toInt() * minutesPerYear` — IntelliJ Amiya, Jun 19 '21 at 09:38
See this answer here: https://stackoverflow.com/questions/7200108/android-gettext-from-edittext-field — Alexander Hoffmann, Jun 19 '21 at 09:39
This is the error log: NumberFormatException: For input string: — Mahdi Massarewa, Jun 19 '21 at 09:40
yeah. i assume that. Make sure your edittext value is `int`. — IntelliJ Amiya, Jun 19 '21 at 09:41
Thanks @IntelliJAmiya Answer is:`val age = edtTxtAge.text.toString().toInt() * minutesPerYear` `txtAge.text = "Your age in minutes is: " + age.toString()` — Mahdi Massarewa, Jun 19 '21 at 09:41

score 1 · Accepted Answer · answered Jun 19 '21 at 09:45

When initialising age you must call "text" before you call to string:

var edtTxtAge = findViewById<EditText>(R.id.edtTxtAge)
    val btnCalc = findViewById<Button>(R.id.btnCalc)
    var txtAge = findViewById<TextView>(R.id.txtAge)

    btnCalc.setOnClickListener(View.OnClickListener {

        val minutesPerYear = 525600
        val age = edtTxtAge.text.toString().toInt() * minutesPerYear
        txtAge.text = "Your age in minutes is: " + age.toString()

    })

Android App crashes when pressing a Button in Kotlin

1 Answers1