小编Sim*_*215的帖子

import 'package:flutter/material.dart';

void main() {
  runApp(Calculator());
}

class Calculator extends StatelessWidget {
  final numpad_background_color = Color(0x212121);
  final background_color = Colors.black;
  final equal_button_background_color = Color(0xffbe00);

  final textColor = Colors.white;
  final operatorTextColor = Color(0xf3ba0e);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        home: Scaffold(
            appBar: appbar(context),
            body: Stack(
              children: [Container(height: MediaQuery.of(context).size.height * 0.37), numpad(context)],
            )));
  }

  Widget appbar(BuildContext context) {
    return AppBar(title: Text("Rechner", style: TextStyle(color: textColor, fontSize: 15)), backgroundColor: background_color, leading: Icon(Icons.history));
  }

  Widget numpad(BuildContext context) {
    return Container(decoration: BoxDecoration(borderRadius: BorderRadius.circular(5), color: numpad_background_color), …