研究与分享面向市场的互联网技术

MediaQueryData queryData;
queryData = MediaQuery.of(context);

queryData.devicePixelRatio

queryData.size.width
queryData.size.height

size.width * queryData.devicePixelRatio
size.height * queryData.devicePixelRatio

void getDeviceInfo() async {
  DeviceInfoPlugin deviceInfo = new DeviceInfoPlugin();
  if(Platform.isAndroid) {
    AndroidDeviceInfo androidInfo = await deviceInfo.androidInfo;    
    print(_readAndroidBuildData(androidInfo).toString());
  } else if (Platform.isIOS) {
    IosDeviceInfo iosInfo = await deviceInfo.iosInfo;
    print(_readIosDeviceInfo(iosInfo).toString());
  }
}

Map<String, dynamic> _readAndroidBuildData(AndroidDeviceInfo build) {
  return <String, dynamic>{
    'version.securityPatch': build.version.securityPatch,
    'version.sdkInt': build.version.sdkInt,
    'version.release': build.version.release,
    'version.previewSdkInt': build.version.previewSdkInt,
    'version.incremental': build.version.incremental,
    'version.codename': build.version.codename,
    'version.baseOS': build.version.baseOS,
    'board': build.board,
    'bootloader': build.bootloader,
    'brand': build.brand,
    'device': build.device,
    'display': build.display,
    'fingerprint': build.fingerprint,
    'hardware': build.hardware,
    'host': build.host,
    'id': build.id,
    'manufacturer': build.manufacturer,
    'model': build.model,
    'product': build.product,
    'supported32BitAbis': build.supported32BitAbis,
    'supported64BitAbis': build.supported64BitAbis,
    'supportedAbis': build.supportedAbis,
    'tags': build.tags,
    'type': build.type,
    'isPhysicalDevice': build.isPhysicalDevice,
    'androidId': build.androidId
  };
}

Map<String, dynamic> _readIosDeviceInfo(IosDeviceInfo data) {
  return <String, dynamic>{
    'name': data.name,
    'systemName': data.systemName,
    'systemVersion': data.systemVersion,
    'model': data.model,
    'localizedModel': data.localizedModel,
    'identifierForVendor': data.identifierForVendor,
    'isPhysicalDevice': data.isPhysicalDevice,
    'utsname.sysname:': data.utsname.sysname,
    'utsname.nodename:': data.utsname.nodename,
    'utsname.release:': data.utsname.release,
    'utsname.version:': data.utsname.version,
    'utsname.machine:': data.utsname.machine,
  };
}

...
bool _saving = false
...

@override
Widget build(BuildContext context) {
  return Scaffold(
     body: ModalProgressHUD(child: Container(
       Form(...)
     ), inAsyncCall: _saving),
  );
}

setState(() {
  _saving = true;
});

setState(() {
  _saving = false;
});

ModalProgressHUD(
  @required inAsyncCall: bool,
  @required child: Widget,
  opacity: double,
  color: Color,
  progressIndicator: CircularProgressIndicator,
  offset: double
  dismissible: bool,
);

import 'package:fluttertoast/fluttertoast.dart';

Fluttertoast.showToast(
    msg: "Toast提示信息",
    toastLength: Toast.LENGTH_SHORT,
    gravity: ToastGravity.CENTER,
    timeInSecForIos: 1,
    backgroundColor: Colors.red,
    textColor: Colors.white,
    fontSize: 16.0
);

RegExp exp = RegExp(
          r'^((13[0-9])|(14[0-9])|(15[0-9])|(16[0-9])|(17[0-9])|(18[0-9])|(19[0-9]))\d{8}$');
bool matched = exp.hasMatch(mobileTextController.text);

import 'dart:async';

class _LoginPageState extends State<LoginPage> {
  ...
  Timer _timer;
  int _countdownTime = 0;
  ...
}

GestureDetector(
  onTap: () {
    if (_countdownTime == 0 && validateMobile()) {
      //Http请求发送验证码
      ...
      setState(() {
        _countdownTime = 60;
      });
      //开始倒计时
      startCountdownTimer();
    }
  },
  child: Text(
    _countdownTime > 0 ? '$_countdownTime后重新获取' : '获取验证码',
    style: TextStyle(
      fontSize: 14,
      color: _countdownTime > 0
          ? Color.fromARGB(255, 183, 184, 195)
          : Color.fromARGB(255, 17, 132, 255),
    ),
  ),
)

void startCountdownTimer() {
  const oneSec = const Duration(seconds: 1);

  var callback = (timer) => {
    setState(() {
      if (_countdownTime < 1) {
        _timer.cancel();
      } else {
        _countdownTime = _countdownTime - 1;
      }
    })
  };

  _timer = Timer.periodic(oneSec, callback);
}

@override
void dispose() {
  super.dispose();
  if (_timer != null) {
    _timer.cancel();
  }
}

import 'package:flutter/material.dart';

class NoSplashFactory extends InteractiveInkFeatureFactory {
  const NoSplashFactory();

  @override
  InteractiveInkFeature create(
      {MaterialInkController controller,
      RenderBox referenceBox,
      Offset position,
      Color color,
      TextDirection textDirection,
      bool containedInkWell = false,
      rectCallback,
      BorderRadius borderRadius,
      ShapeBorder customBorder,
      double radius,
      onRemoved}) {
    return new NoSplash(
      controller: controller,
      referenceBox: referenceBox,
    );
  }
}

class NoSplash extends InteractiveInkFeature {
  NoSplash({
    @required MaterialInkController controller,
    @required RenderBox referenceBox,
  })  : assert(controller != null),
        assert(referenceBox != null),
        super(
          controller: controller,
          referenceBox: referenceBox,
        );

  @override
  void paintFeature(Canvas canvas, Matrix4 transform) {}
}

...
child: Theme(
    data: ThemeData(splashFactory: const NoSplashFactory()),
    child: TextField(
      ...                          
    ),
),
...

import 'dart:convert';
import 'package:convert/convert.dart';
import 'package:crypto/crypto.dart' as crypto;

String generateMd5(String data) {
  var content = new Utf8Encoder().convert(data);
  var md5 = crypto.md5;
  var digest = md5.convert(content);
  return hex.encode(digest.bytes);
}

void main() {
  //这一句将状态更改为亮色
  SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle.light);
  runApp(MyApp());
}