Calculator app

app/build.gradle

@@ -31,6 +31,9 @@ dependencies {
     implementation 'androidx.appcompat:appcompat:1.2.0'
     implementation 'androidx.core:core-ktx:1.3.2'
     implementation 'androidx.constraintlayout:constraintlayout:2.0.2'
+    implementation 'androidx.navigation:navigation-fragment-ktx:2.3.1'
+    implementation 'androidx.navigation:navigation-ui-ktx:2.3.1'
+    implementation 'androidx.legacy:legacy-support-v4:1.0.0'
     testImplementation 'junit:junit:4.12'
     androidTestImplementation 'androidx.test.ext:junit:1.1.2'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'

app/src/main/java/com/scainitiative/kotlinscainitiativeproject/MainActivity.kt

@@ -2,14 +2,87 @@ package com.scainitiative.kotlinscainitiativeproject
 
 import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
+import android.view.View
 import android.view.WindowManager
+import android.widget.Button
+import kotlinx.android.synthetic.main.activity_main.*
 
 class MainActivity : AppCompatActivity() {
 
+    var isOperator = true
+    var numbers = ""
+    var operators = "+"
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_main)
         val w = window;
         w.setFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS, WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS)
     }
+
+    fun numberClicked(view: View) {
+        if (isOperator)
+            displayEdittext.setText("")
+        isOperator = false
+
+        var buttonClicked  =  displayEdittext.text.toString()
+        var buttonSelected  =  view as Button
+        when(buttonSelected.id){
+
+            cal_one.id -> {buttonClicked  += "1"}
+            cal_two.id -> {buttonClicked  += "2"}
+            cal_three.id -> {buttonClicked  += "3"}
+            cal_four.id -> {buttonClicked  += "4"}
+            cal_five.id -> {buttonClicked  += "5"}
+            cal_six.id -> {buttonClicked  += "6"}
+            cal_seven.id -> {buttonClicked  += "7"}
+            cal_eight.id -> {buttonClicked  += "8"}
+            cal_nine.id -> {buttonClicked  += "9"}
+            cal_zero.id -> {buttonClicked  += "0"}
+            cal_full_stop.id -> {buttonClicked  +=  "."}
+            cal_add_minus.id -> {buttonClicked  + "-$buttonClicked"}
+
+        }
+        displayEdittext.setText(buttonClicked)
+
+    }
+
+    fun signOperation(view: View) {
+        isOperator = true
+        numbers = displayEdittext.text.toString()
+        var buttonSelected = view as Button
+        when (buttonSelected.id){
+            cal_minus.id -> operators = "-"
+            cal_divide.id -> operators = "/"
+            cal_multiply.id -> operators = "*"
+            cal_plus.id -> operators = "+"
+        }
+
+
+    }
+
+    fun equalTo(view: View) {
+        var anumber = displayEdittext.text.toString()
+        var result = 0.0
+        when (operators){
+            "+" -> {result = numbers.toDouble() + anumber.toDouble()}
+            "*" -> {result = numbers.toDouble() * anumber.toDouble()}
+            "-" -> {result = numbers.toDouble() - anumber.toDouble()}
+            "/" -> {result = numbers.toDouble() / anumber.toDouble()}
+        }
+        displayEdittext.setText(result.toString())
+
+    }
+
+    fun clear(view: View) {
+        displayEdittext.setText("0")
+        isOperator = true
+    }
+
+    fun percentage(view: View) {
+        var num = displayEdittext.text.toString().toDouble()/100
+        displayEdittext.setText(num.toString())
+        isOperator = true
+
+    }
 }

app/src/main/res/drawable/ic_baseline_arrow_downward_24.xml

@@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="#261CFF"
+    android:viewportHeight="24" android:viewportWidth="24"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="@android:color/white" android:pathData="M20,12l-1.41,-1.41L13,16.17V4h-2v12.17l-5.58,-5.59L4,12l8,8 8,-8z"/>
+</vector>