Flutter 中未定义“SystemChrome”

Question

我是 Flutter 的新手，我想更改应用程序的状态栏颜色。经过一番谷歌搜索，我找到了一种方法。是在我的main函数中添加以下代码。

SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle(
  statusBarColor: Colors.white
));

但是在添加它并运行我的应用程序后，我收到以下错误：-

Compiler message:                                                       
lib/main.dart:15:40: Error: Method not found: 'SystemUiOverlayStyle'.   
  SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle(            
                                       ^^^^^^^^^^^^^^^^^^^^             
lib/main.dart:15:3: Error: Getter not found: 'SystemChrome'.            
  SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle(            
  ^^^^^^^^^^^^                                              

请告诉我是什么问题。提前致谢！

---

我的main功能：-

Compiler message:                                                       
lib/main.dart:15:40: Error: Method not found: 'SystemUiOverlayStyle'.   
  SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle(            
                                       ^^^^^^^^^^^^^^^^^^^^             
lib/main.dart:15:3: Error: Getter not found: 'SystemChrome'.            
  SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle(            
  ^^^^^^^^^^^^                                              

---

我的pubspec.yaml档案：-

name: william_client
description: Client App for William Assistant and TV.
version: 1.0.0+1

environment:
  sdk: ">=2.1.0 <3.0.0"

dependencies:
  firebase_auth: 0.8.4+5
  cloud_firestore: 0.10.1
  flutter:
    sdk: flutter
  cupertino_icons: ^0.1.2

dev_dependencies:
  flutter_test:
    sdk: flutter

flutter:

  fonts:
    - family: Montserrat
      fonts:
        - asset: fonts/Montserrat.ttf
    - family: MontserratLight
      fonts:
        - asset: fonts/Montserrat-Light.ttf
    - family: RobotoMono
      fonts:
        - asset: fonts/RobotoMono.ttf

Answer 1

你应该添加

import 'package:flutter/services.dart';