Flutter — 本地资源使用（图片及iconfont）以及 定时器

需要在 yaml 文件中配置

name: flutter_app
description: A new Flutter application.

# The following defines the version and build number for your application.
# A version number is three numbers separated by dots, like 1.2.43
# followed by an optional build number separated by a +.
# Both the version and the builder number may be overridden in flutter
# build by specifying --build-name and --build-number, respectively.
# In Android, build-name is used as versionName while build-number used as versionCode.
# Read more about Android versioning at https://developer.android.com/studio/publish/versioning
# In iOS, build-name is used as CFBundleShortVersionString while build-number used as CFBundleVersion.
# Read more about iOS versioning at
# https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
version: 1.0.0+1

environment:
  sdk: ">=2.1.0 <3.0.0"

dependencies:
  flutter:
    sdk: flutter
  dio: ^3.0.4

  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^0.1.2
  english_words: ^3.1.0

dev_dependencies:
  flutter_test:
    sdk: flutter


# For information on the generic Dart part of this file, see the
# following page: https://dart.dev/tools/pub/pubspec

# The following section is specific to Flutter.
flutter:

  # The following line ensures that the Material Icons font is
  # included with your application, so that you can use the icons in
  # the material Icons class.
  uses-material-design: true

  # To add assets to your application, add an assets section, like this:
  assets:
    - assets/images/11.jpg

    # An image asset can refer to one or more resolution-specific "variants", see
    # https://flutter.dev/assets-and-images/#resolution-aware.

    # For details regarding adding assets from package dependencies, see
    # https://flutter.dev/assets-and-images/#from-packages

    # To add custom fonts to your application, add a fonts section here,
    # in this "flutter" section. Each entry in this list should have a
    # "family" key with the font family name, and a "fonts" key with a
    # list giving the asset and other descriptors for the font. For
    # example:
  fonts:
    - family: Iconfont
      fonts:
        - asset: assets/fonts/iconfont.ttf
          weight: 400

  # For details regarding fonts from package dependencies,
  # see https://flutter.dev/custom-fonts/#from-packages

配置完后使用

import 'package:flutter/material.dart';
import 'package:dio/dio.dart';
import 'dart:convert' as JSON;

void main() async {
  runApp(MyApp());
}


class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return MaterialApp(
      title: 'List Demo',
      home:Center(
        child: Column(
          children: <Widget>[
            Image.asset('assets/images/11.jpg'),
            Icon( IconData(0xe60d, fontFamily: 'Iconfont'),color: Colors.blue,size: 89.0)
          ],
        ),
      )
    );
  }
}

定时器

import 'dart:async';

main(){
  const timeout = const Duration(seconds: 3);
  const ms = const Duration(microseconds: 1);

  startTimeout([int microseconds]){
    var duration = microseconds == null ? timeout : ms * microseconds;
    return Timer(duration,(){
      print('@@@@');
    });
  }

  startTimeout();
}