app ready

Author: lyadhcoder

lib/main.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:math_expressions/math_expressions.dart';
 
 void main(){
   runApp(Calculator());
@@ -46,6 +47,17 @@ class _SimpleCalculatorState extends State<SimpleCalculator> {
       }else if(buttonText == "="){
         equationFontSize = 38.0;
         resultFontSize = 48.0;
+        expression = equation;
+        expression = expression.replaceAll('x', '*');
+        expression = expression.replaceAll('÷', '/');
+        try{
+          Parser p = Parser();
+          Expression exp = p.parse(expression);
+          ContextModel cm = ContextModel();
+          result = '${exp.evaluate(EvaluationType.REAL, cm)}';
+        }catch(e){
+          result = "Error";
+        }
       }else{
         equationFontSize = 48.0;
         resultFontSize = 38.0;

pubspec.lock

@@ -88,6 +88,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.12.6"
+  math_expressions:
+    dependency: "direct main"
+    description:
+      name: math_expressions
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.0"
   meta:
     dependency: transitive
     description:

pubspec.yaml

@@ -20,9 +20,11 @@ dependencies:
   flutter:
     sdk: flutter
 
+
   # The following adds the Cupertino Icons font to your application.
   # Use with the CupertinoIcons class for iOS style icons.
   cupertino_icons: ^0.1.2
+  math_expressions: ^2.0.0
 
 dev_dependencies:
   flutter_test: