AdrianAndroid的专栏

资料Flutter异步编程-Future事件循环EventLoopEvent Queue 主要包含IO、手势、绘制、定时器(Timer)、Stream流以及本文所讲Future等MicroTask Queue 主要包含Dart内部的微任务(内部非常短暂操作)，一般是通过 scheduleMicroTask 方法实现调度，它的优先级比Event Queue要高事件循环执行的流程Future的几种情况1. factory Future(FutureOr computation())//F

Step 0:Create the app base codeStep 1:Diagram the layoutStep 2:Implement the title rowWidget titleSection = Container( padding: const EdgeInsets.all(32), child: Row( children: [ Expan...

Creating a stateful widgetStep 0: Get readyStep1: Decide which object manages the widget’s stateStep2: Subclass StatefulWidgetclass FavoriteWidget extends StatefulWidget { @override _FavoriteW...

#Samplefinal _formKey = GlobalKey<FormState>();@overrideWidget build(BuildContext context) { return Form( key: _formKey, child: Column( crossAxisAlignment: CrossAxisAlignment...

SampleString dropdownValue = 'One';// ...Widget build(BuildContext context) { return Scaffold( body: Center( child: DropdownButton<String>( value: dropdownValue, ...

#SampleFlatButton( color: Colors.blue, textColor: Colors.white, disabledColor: Colors.grey, disabledTextColor: Colors.black, padding: EdgeInsets.all(8.0), splashColor: Colors.blueAccent,...

SampleWidget build(BuildContext context) { return Scaffold( appBar: AppBar( title: Text('Floating Action Button Sample'), ), body: Center( child: Text('Press the button belo...

0Sampledouble _volume = 0.0;// ...Widget build(BuildContext context) { return Scaffold( body: Center( child: Column( mainAxisSize: MainAxisSize.min, children: <Wid...

SampleWidget build(BuildContext context) { return Center( child: Column( mainAxisSize: MainAxisSize.min, children: <Widget>[ const RaisedButton( onPressed: n...

A basic Dart program// Define a function.printInteger(int aNumber) { print('The number is $aNumber.'); // Print to console.}// This is where the app starts executing.main() { var number = 42...

Specifying assetspubspec.yamlflutter: assets: - assets/my_icon.png - assets/background.pngflutter: assets: - assets/Asset bundlingAsset variants .../pubspec.yaml .../graphics...

This recipe uses the following steps.Add the http package.Make a network request using the http package.Convert the response into a custom Dart object.Fetch and display the data with Flutter.1....

Add authorization headersFuture<http.Response> fetchPost() { return http.get( 'https://jsonplaceholder.typicode.com/posts/1', // Send authorization headers to the backend. headers...

Add the http packageMake a network request using the http package.Convert the response into a list photosMove this work to a separate isolate.1. Add the http packagedependencies: http: <la...

Flutter Go 代码开发规范 0.1.0 版代码风格标识符三种类型大驼峰类、枚举、typedef和类型参数 class SliderMenu { ... } class HttpRequest { ... } typedef Predicate = bool Function<T>(T value);包括用于元数据注释的类 class Fo...

VSCode先运行flutter的时候出现白屏命令行出现如下错误：E/flutter ( 2918): [ERROR:flutter/shell/gpu/gpu_surface_gl.cc(58)] Failed to setup Skia Gr context.这是在x86情况下遇到的问题。配置下命令行就可以了找到Add Configuration配置选项添加Dart/Flutte...

Select a layout widgetCreate a visible widgetAdd the visible widget to the layout widgetAdd the layout widget to the pagevar stars = Row( mainAxisSize: MainAxisSize.min, ch...

Hello Worldimport 'package:flutter/material.dart';void main() { runApp( Center( child: Text( 'Hello, world!', textDirection: TextDirection.ltr, ), ), );}...

Connect to a WebSocket serverListen for messages from the serverSend data to the serverClose the WebSocket connection1. Connect to a WebSocket serverfinal channel = IOWebSocketChannel.connect('...

Add the dependencies.Define the Dog data model.Open the database.Create the dogs table.Insert a Dog into the database.Retrieve the list of dogs.Update a Dog in the database.Delete a Dog from t...

Start with a Row and some childrenimport 'package:flutter_web/material.dart';import 'package:flutter_web_test/flutter_web_test.dart';import 'package:flutter_web_ui/ui.dart' as ui;class MyWidget e...

Which JSON serializtion method is right for me?Use manual serialization for smaller projectsUse code generation for medium to large projectsIs there a GSON/Jackson/Moshi equivalent in Flutter?Seri...

资料Flutter 控件之 ScaffoldWidgetScaffoldScaffold 有下面几个主要属性：appBar：显示在界面顶部的一个 AppBar，也就是 Android 中的 ActionBar 、Toolbarbody：当前界面所显示的主要内容 WidgetfloatingActionButton：纸墨设计中所定义的 FAB，界面的主要功能按钮persistent...

import 'package:flutter/material.dart';void main() => runApp(MyApp());class MyApp extends StatelessWidget { @override Widget build(BuildContext context) { final title = 'Grid List'; ...

import 'package:flutter/foundation.dart';import 'package:flutter/material.dart';void main() { runApp(MyApp( items: List<ListItem>.generate( 1000, (i) => i % 6 == 0 ...

import 'package:flutter/foundation.dart';import 'package:flutter/material.dart';void main() => runApp(MyApp());class MyApp extends StatelessWidget { MyApp({Key key}) : super(key: key); @o...

import 'package:flutter/material.dart';void main() { runApp(MaterialApp( title: 'Returning Data', home: HomeScreen(), ));}class HomeScreen extends StatelessWidget { @override Widg...

import 'package:flutter/foundation.dart';import 'package:flutter/material.dart';void main() { runApp(MyApp( items: List<String>.generate(10000, (i) => "Item $i"), ));}class MyAp...

import 'package:flutter/material.dart';import 'package:flutter_test/flutter_test.dart';void main() { // Define a test. The TestWidgets function also provides a WidgetTester // to work with. The...

import 'package:flutter/material.dart';void main() => runApp(HeroApp());class HeroApp extends StatelessWidget { @override Widget build(BuildContext context) { return MaterialApp( ...

import 'package:flutter/material.dart';void main() { runApp(MaterialApp( title: 'Navigation Basics', home: FirstRoute(), ));}class FirstRoute extends StatelessWidget { @override W...

import 'package:flutter/material.dart';void main() { runApp(MaterialApp( title: 'Named Routes Demo', // Start the app with the "/" named route. In this case, the app starts // on the F...

import 'package:flutter/material.dart';void main() => runApp(MyApp());class MyApp extends StatelessWidget { @override Widget build(BuildContext context) { return MaterialApp( // P...

import 'package:flutter/material.dart';void main() => runApp(MyApp());class MyApp extends StatelessWidget { @override Widget build(BuildContext context) { return MaterialApp( // P...

Dart数据类型在Dart里是强类型的，也有自动推断类型的机制定义变量使用:var, const, dynamic, Object, 类型等方式//基本类型import 'dart:math';var name = 'Voyager I';var antennaDiameter = 3.7;const image = { 'tags': ['Jupiter', 'Saturn'...