随诊医生开发---1.2. 创建主界面

创建主界面

由于需要针对基层医疗机构出诊及家庭医生需求，需要快速开发出一个简单的移动应用，决定采用Google在2018年2月新推出的Flutter技术，来开发这个新的App。
首先主页的底部像大多数应用一样，有一个TabBar，共有5个选项：

• 日程
  记录医生在医院出诊、预约计划和执行情况，以及走访社区出诊计划和执行情况。在医院就诊需要记录医院、科室和出诊时间，外出出诊需要记录时间、患者信息。
• 患者
  患者列表信息，可以对患者进行分组（以标签形式），可以查找患者，点击某个患者，可以看到患者的详细信息，继续点击可以看到历史病历信息。这部分内容原则上来自于基层医疗机构的HIS系统，在初期可以只使用本系统数据。
• 消息
  医患之间可以通过图文消息方式进行沟通。医生还可以通过这个界面发送患教文章给指定患者。
• 医院
  医院的一些管理功能，包括排班信息、患者签约、家庭病床、通知公告。
• 我的
  可以进行一些个性化设置，如是否接收患者咨询等。

建立底部选项卡

底部选项卡每个代表一个页面，因此我们需要定义5个新页面。我们在Android Studio中选中工程的lib文件夹，点击右键，创建一个文件夹命名为views，将所有程序中用到的页面放到此文件中。然后选中该文件夹，点击右键，新建dart文件，分别建立如下5个文件：

• 日程

import 'package:flutter/material.dart';

class SchedulePage extends StatefulWidget {
  @override
  SchedulePageState createState() => new SchedulePageState();
}

class SchedulePageState extends State<SchedulePage> {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(
        title: new Text('日程管理')
      ),
      body: new Center(
        child: new Text('医生日程管理')
      )
    );
  }
}

• 患者

import 'package:flutter/material.dart';

class PatientPage extends StatefulWidget {
  @override
  PatientPageState createState() => new PatientPageState();
}

class PatientPageState extends State<PatientPage> {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
        appBar: new AppBar(
            title: new Text('患者管理')
        ),
        body: new Center(
            child: new Text('患者管理之患者列表')
        )
    );
  }
}

• 消息

import 'package:flutter/material.dart';

class ImPage extends StatefulWidget {
  @override
  ImPageState createState() => new ImPageState();
}

class ImPageState extends State<ImPage> {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
        appBar: new AppBar(
            title: new Text('消息管理')
        ),
        body: new Center(
            child: new Text('消息管理之消息列表')
        )
    );
  }
}

• 医院

import 'package:flutter/material.dart';

class HospitalPage extends StatefulWidget {
  @override
  HospitalPageState createState() => new HospitalPageState();
}

class HospitalPageState extends State<HospitalPage> {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
        appBar: new AppBar(
            title: new Text('医院行政管理')
        ),
        body: new Center(
            child: new Text('医院行政管理页面')
        )
    );
  }
}

• 我的

import 'package:flutter/material.dart';

class MinePage extends StatefulWidget {
  @override
  MinePageState createState() => new MinePageState();
}

class MinePageState extends State<MinePage> {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
        appBar: new AppBar(
            title: new Text('我的')
        ),
        body: new Center(
            child: new Text('我的管理')
        )
    );
  }
}

我们还需在主界面中加入我们定义的TabBar，打开main.dart文件，将内容修改为如下所示：

import 'package:flutter/material.dart';
import './views/SchedulePage.dart';
import './views/PatientPage.dart';
import './views/ImPage.dart';
import './views/HospitalPage.dart';
import './views/MinePage.dart';

void main() => runApp(new MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Flutter Demo',
      theme: new ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or press Run > Flutter Hot Reload in IntelliJ). Notice that the
        // counter didn't reset back to zero; the application is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: new MyHomePage(title: '随诊医生'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> with SingleTickerProviderStateMixin {
  int _counter = 0;

  TabController tabController;

  @override
  void initState() {
    tabController = new TabController(vsync: this, length: 5);
  }

  @override
  void dispose() {
    tabController.dispose();
    super.dispose();
  }

  void _incrementCounter() {
    setState(() {
      // This call to setState tells the Flutter framework that something has
      // changed in this State, which causes it to rerun the build method below
      // so that the display can reflect the updated values. If we changed
      // _counter without calling setState(), then the build method would not be
      // called again, and so nothing would appear to happen.
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return new Scaffold(
      body: new TabBarView(
        controller: tabController,
        children: <Widget>[
          new SchedulePage(),
          new PatientPage(),
          new ImPage(),
          new HospitalPage(),
          new MinePage()
        ],
      ),
      bottomNavigationBar: new Material(
        color: Colors.lightBlue,
        child: new TabBar(
          controller: tabController,
          tabs: <Tab>[
            new Tab(text: '日程', icon: new Icon(Icons.home)),
            new Tab(text: '患者', icon: new Icon(Icons.account_box)),
            new Tab(text: '消息', icon: new Icon(Icons.chat_bubble_outline)),
            new Tab(text: '医院', icon: new Icon(Icons.apps)),
            new Tab(text: '我的', icon: new Icon(Icons.build)),
          ]
        )
      ),
      floatingActionButton: new FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: new Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

这部分代码应该还是很好理解的，而且Flutter一个非常好的特性就是他提供了很多预置的内容，比如TabBar的图标，就不用我们费时费力去找，直接使用即可。
在Android Studio中运行该程序，可以得到如下所示的界面：

写到这里不禁感慨，Google的Flutter真的十分强大，从完全不知道Flutter为何物，到做出这个界面，除去系统安装之外，仅仅花了不到一个小时的时间，还包括百度一些奇奇怪怪的东西，太强大了。而且这个程序不仅可以在Android上运行，还可以在IOS系统上运行，性能上优于流行的ReactNative，忍不住要为Google Flutter点赞了。