import 'package:flutter/material.dart'; class LoginPage extends StatefulWidget { @override _LoginPageState createState() => _LoginPageState(); } class _LoginPageState extends State<LoginPage> { @override Widget build(BuildContext context) { var scaffold = Scaffold( appBar: new AppBar( leading: Builder( builder: (BuildContext context) { return IconButton( icon: new Icon(Icons.keyboard_backspace), onPressed: _pushSaved, ); }, ), title: new Text('登錄'), ), body: Container( child: new Column( // start ,沿着主軸方向(垂直方向)頂部對齊; // end,沿着主軸方向(垂直方向)底部對齊; // center,沿着主軸方向(垂直方向)居中對齊; // spaceBetween ,沿着主軸方向(垂直方向)平分剩餘空間; // spaceAround,把剩餘空間平分紅n份,n是子widget的數量,而後把其中一份空間分紅2份,放在第一個child的前面,和最後一個child的後面; // spaceEvenly,把剩餘空間平分n+1份,而後平分全部的空間,請注意和spaceAround的區別; mainAxisAlignment: MainAxisAlignment.start, //在主軸方向佔有空間的值,默認是max mainAxisSize: MainAxisSize.max, // start ,垂直主軸方向(水平方向)左側對齊; // end,垂直主軸方向(水平方向)右側對齊; // center,垂直主軸方向(水平方向)居中對齊; // stretch ,垂直主軸方向(水平方向)拉伸子child; // baseline,和textBaseline一塊兒使用, crossAxisAlignment: CrossAxisAlignment.start, // textDirection:文字佈局方向 //TextDirection.ltr ,從左到右; // TextDirection.rtl,從右到作佈局; textDirection:TextDirection.ltr, // down ,從上向下佈局; // up,反過來從下向上佈局 verticalDirection: VerticalDirection.down, textBaseline: TextBaseline.alphabetic, children: <Widget>[ new Text( '密碼登錄', style: new TextStyle( color: Colors.black, fontWeight: FontWeight.bold, ), ), Container( color: Colors.blue, height: 60, width: 60, ), Container( color: Colors.yellow, height: 60, width: 60, ), ], ), ), ); return scaffold; } void _pushSaved() {} }