I was doing an APP following this tutorial --- https://www.youtube.com/watch?v=lTyyNpY7hy0

Ofc the code was deprecated since it uses android.extensions, so i decided to go with the updated implementation by using viewBinding

however the after running the buttons are not working and thus text is not being displayed in the output

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.core.content.ContextCompat
import com.thomas.calculadoracompleta.databinding.ActivityMainBinding
import org.mariuszgromada.math.mxparser.Expression
import java.lang.Exception
import java.text.DecimalFormat

private lateinit var binding: ActivityMainBinding

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        val view = binding.root
        setContentView(view)

        binding.buttonClear.setOnClickListener {
            binding.input.text = ""
            binding.output.text = ""

        }

        binding.buttonBracketLeft.setOnClickListener {
            binding.input.text = addToInputText("(")

        }

        binding.buttonBracketRight.setOnClickListener {
            binding.input.text = addToInputText(")")

        }

        binding.buttonDivision.setOnClickListener {
            binding.input.text = addToInputText("÷")

        }

        binding.button7.setOnClickListener {
            binding.input.text = addToInputText("7")

        }

        binding.button8.setOnClickListener {
            binding.input.text = addToInputText("8")

        }

        binding.button9.setOnClickListener {
            binding.input.text = addToInputText("9")

        }

        binding.buttonMultiply.setOnClickListener {
            binding.input.text = addToInputText("×")

        }

        binding.button4.setOnClickListener {
            binding.input.text = addToInputText("4")

        }

        binding.button5.setOnClickListener {
            binding.input.text = addToInputText("5")

        }

        binding.button6.setOnClickListener {
            binding.input.text = addToInputText("6")

        }

        binding.buttonSubtraction.setOnClickListener {
            binding.input.text = addToInputText("-")

        }

        binding.button5.setOnClickListener {
            binding.input.text = addToInputText("1")

        }

        binding.button4.setOnClickListener {
            binding.input.text = addToInputText("2")

        }

        binding.button3.setOnClickListener {
            binding.input.text = addToInputText("3")

        }

        binding.buttonAddition.setOnClickListener {
            binding.input.text = addToInputText(" ")

        }

        binding.button0.setOnClickListener {
            binding.input.text = addToInputText("0")

        }

        binding.buttonDot.setOnClickListener {
            binding.input.text = addToInputText(".")

        }

        binding.buttonEquals.setOnClickListener {
            showResult()

        }

    }

    private fun addToInputText(buttonValue: String): String {
        return "${binding.input.text}$buttonValue"
    }

    private fun getInputExpression(): String {
        var expression = binding.input.text.replace(Regex("÷"), "/")
        expression = expression.replace(Regex("×"),"*")
        return expression
    }

    private fun showResult(){

        try {
            val expression = getInputExpression()
            val result = Expression(expression).calculate()
            if(result.isNaN()){
                binding.output.text = "Error"
            } else {
                binding.output.text = DecimalFormat("0.######").format(result).toString()
            }
        } catch (e: Exception){

        }

    }

the problem is that buttons aren't working.

i'll add the xml

?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:background="@color/window_background"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:gravity="bottom"
        android:padding="30dp"
        android:background="@color/io_background"
        android:orientation="vertical">

        <TextView
            android:id="@ id/input"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="end"
            android:textSize="30sp"
            android:textColor="@color/white"
            tools:text="5 10-3" />
        <TextView
            android:id="@ id/output"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="end"
            android:textSize="50sp"
            android:textColor="@color/green"
            tools:text="12" />
    </LinearLayout>

    <TableLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:stretchColumns="*">

        <TableRow>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_clear"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="C"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_bracket_left"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="("/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_bracket_right"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text=")"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_division"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="÷"/>
        </TableRow>

        <TableRow>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_7"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="7" />

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_8"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="8"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_9"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="9"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_multiply"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="×"/>
        </TableRow>

        <TableRow>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_4"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="4"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_5"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="5"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_6"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="6"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_subtraction"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="-"/>
        </TableRow>

        <TableRow>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_1"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="1"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_2"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="2"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_3"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="3"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_addition"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text=" "/>
        </TableRow>

        <TableRow>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_0"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="0"/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_dot"
                android:layout_width="wrap_content"
                android:layout_height= "90dp"
                style="@style/Button_Style"
                android:text="."/>

            <androidx.appcompat.widget.AppCompatButton
                android:id="@ id/button_equals"
                android:layout_width="0dp"
                android:layout_height= "90dp"
                android:layout_weight="1"
                style="@style/Button_Style"
                android:text="="/>

        </TableRow>




    </TableLayout>
</LinearLayout>
´´´

CodePudding user response：

put your binding inside activity class

class MainActivity : AppCompatActivity() {
   // Here
    private lateinit var binding: ActivityMainBinding

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

CodePudding user response：

Actually it was a XML problem fixed it after and now everything is working perfectly.