Android Studio – My application keep crashing when I click on the convert button even though my codes have no fatal errors

I am trying to build an application for my mini assignment, it is to create a temp converter tool. However, most of the codes out there are in java and since my assignment must be done in Kotlin. I must figure a way out myself.

This is my current code, and as you can see there are no errors, but when I click on the convert button, it will say my application crash.

Activity.kt

package edu.blabladmaoa.travelapp
import android.content.Intent
import android.os.Bundle
import android.provider.MediaStore
import android.widget.*
import androidx.appcompat.app.AppCompatActivity
import org.w3c.dom.Text


class TempConverterActivity : AppCompatActivity() {

    val TAG: String = "TempConverter"

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_temp_converter)

       
        val userinput = findViewById<EditText>(R.id.editTextTemp)
        val optionFah = findViewById<RadioButton>(R.id.radioButtonFah)
        val optionCel = findViewById<RadioButton>(R.id.radioButtonCel)
        val convertbutton = findViewById<Button>(R.id.convertbutton)
        val clearbutton = findViewById<Button>(R.id.clearbutton)
        val results = findViewById<TextView>(R.id.tempresult)

        // now the buttons are identified, i will set the each button to have their own listener
        convertbutton.setOnClickListener{
            if (optionFah.isChecked()){
                val newinput = userinput.toString().toFloat()
                results.setText(convertCelsiusToFahrenheit(newinput).toString())
            }
            else if (optionCel.isChecked()){
                val newinput = userinput.toString().toFloat()
                convertFahrenheitToCelsius(newinput)
                results.setText(convertCelsiusToFahrenheit(newinput).toString())
            }
        }

        clearbutton.setOnClickListener{
            userinput.text.clear()
        }

    }


    
    private fun convertFahrenheitToCelsius(fahrenheit: Float): Float {
        return ((fahrenheit - 32) * 5 / 9)
    }

  
    private fun convertCelsiusToFahrenheit(celsius: Float): Float {
        return ((celsius * 9) / 5) + 32
    }

}

activity.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">


    <!--    i use "phone" to show numpad instead of normal keyboard-->

    <EditText
        android:id="@+id/editTextTemp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="number"
        android:hint="Enter temperature here" />

    <RadioButton
        android:id="@+id/radioButtonFah"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="to Fahrenheit" />

    <RadioButton
        android:id="@+id/radioButtonCel"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="to Celcius" />

    <Button
        android:id="@+id/convertbutton"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Convert" />

    <Button
        android:id="@+id/clearbutton"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Clear" />

    <TextView
        android:id="@+id/tempresult"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />


</LinearLayout>

Android_Manifest

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="edu.blabladmaoa.travelapp">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.TravelApp">
        <activity
            android:name=".MainActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
                
            </intent-filter>
        </activity>

        <activity
            android:name=".TempConverterActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
 
</application>

</manifest>

Expected Output