Question

我正在尝试复制此图片所示的相同布局：

https://www.internalpointers.com/post/squash-commits-into-one-git

实际上，我在中心处有一个大圆圈，并带有“开始”字样。我使用了一个容器，将其整形为圆形。我正在努力放置其他圈子。我尝试使用位置小部件，但我的圈子被裁剪了，无法完全显示。有人有主意吗？

Answer 1

使用堆栈和定位，您可以根据需要添加更多的圆并更改颜色。

完整代码

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: 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 simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

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() => _MyHomePageState();
}

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

  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 Scaffold(
      appBar: AppBar(
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Center(
        // Center is a layout widget. It takes a single child and positions it
        // in the middle of the parent.
        child: Column(
          // Column is also layout widget. It takes a list of children and
          // arranges them vertically. By default, it sizes itself to fit its
          // children horizontally, and tries to be as tall as its parent.
          //
          // Invoke "debug painting" (press "p" in the console, choose the
          // "Toggle Debug Paint" action from the Flutter Inspector in Android
          // Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
          // to see the wireframe for each widget.
          //
          // Column has various properties to control how it sizes itself and
          // how it positions its children. Here we use mainAxisAlignment to
          // center the children vertically; the main axis here is the vertical
          // axis because Columns are vertical (the cross axis would be
          // horizontal).
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            CircularButton(),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

class CircularButton extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      height: 300,
      child: Stack(
        children: <Widget>[
          Positioned(
              right: 150,
              top: 10,
              child: ClipOval(
                child: Container(
                  color: Colors.grey,
                  height: 20.0, // height of the button
                  width: 20.0, // width of the button
                ),
              )),
          Center(
              child: ClipOval(
            child: Container(
              color: Colors.grey,
              height: 150.0, // height of the button
              width: 150.0, // width of the button
            ),
          )),
          Center(
              child: GestureDetector(
            onTap: () {},
            child: ClipOval(
              child: Container(
                //color: Colors.green,
                height: 120.0, // height of the button
                width: 120.0, // width of the button
                decoration: BoxDecoration(
                    color: Colors.green,
                    border: Border.all(
                        color: Colors.white,
                        width: 10.0,
                        style: BorderStyle.solid),
                    boxShadow: [
                      BoxShadow(
                          color: Colors.grey,
                          offset: Offset(21.0, 10.0),
                          blurRadius: 20.0,
                          spreadRadius: 40.0)
                    ],
                    shape: BoxShape.circle),
                child: Center(
                    child: Text('START',
                        style:
                            TextStyle(color: Colors.white.withOpacity(0.6)))),
              ),
            ),
          )),
          Positioned(
              top: 10,
              left: 10,
              child: ClipOval(
                child: Container(
                  color: Colors.grey,
                  height: 30.0, // height of the button
                  width: 30.0, // width of the button
                ),
              )),
          Positioned(
              top: 50,
              left: 50,
              child: ClipOval(
                child: Container(
                  color: Colors.grey,
                  height: 20.0, // height of the button
                  width: 20.0, // width of the button
                ),
              )),
          Positioned(
              bottom: 50,
              right: 50,
              child: ClipOval(
                child: Container(
                  color: Colors.grey,
                  height: 15.0, // height of the button
                  width: 15.0, // width of the button
                ),
              )),
        ],
      ),
    );
  }
}

在另一个圆周围创建圆

1 个答案: