Flutter——最详细的Container（容器）使用教程

• 创建一个指定宽高的容器

import 'package:flutter/material.dart';
class CustomContainer extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      alignment: Alignment.topLeft,
      width: 200,
      height: 200,
      color: Colors.red,
    );
  }
}

• 容器里面放一个子组件

import 'package:flutter/material.dart';
class ContainerWithChild extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      alignment: Alignment.topLeft,
      padding: EdgeInsets.all(20),
      margin: EdgeInsets.all(10),
      width: 200,
      height: 200,
      color: Colors.grey,
      child: Icon(Icons.android),
    );
  }
}

• 子组件容器底部对齐

import 'package:flutter/material.dart';
class ContainerAlignment extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      alignment: Alignment.bottomRight,
      width: 200,
      height: 200,
      color: Colors.grey,
      child: Icon(
        Icons.android,
        color: Colors.green,
      ),
    );
  }
}

• 添加一个装饰容器的布局
  需要注意的是，当装饰器里面设置了Color背景颜色，则Container的Color属性不能使用，二者只取其一

import 'package:flutter/material.dart';
class ContainerDecoration extends StatelessWidget {

  final List rainbow = [
    0xffff0000,
    0xffFF7F00,
    0xffFFFF00,
    0xff00FF00,
    0xff00FFFF,
    0xff0000FF,
    0xff8B00FF
  ];
 final List stops = [0.0, 1 / 6, 2 / 6, 3 / 6, 4 / 6, 5 / 6, 1.0];
  @override
  Widget build(BuildContext context) {

    return Container(//容器
      alignment: Alignment.center,
      width: 200,
      height: 200,
      margin: EdgeInsets.all(20),
      padding: EdgeInsets.all(20),
      decoration: BoxDecoration(//添加渐变色
          gradient: LinearGradient(
              stops: stops,
              colors: rainbow.map((e) => Color(e)).toList()),
          borderRadius: BorderRadius.only(//添加圆角
              topLeft: Radius.circular(50),
              bottomRight: Radius.circular(50)),
          boxShadow: [
            BoxShadow(
                color: Colors.grey,
                offset: Offset(1, 1),
                blurRadius: 10,
                spreadRadius: 1),
          ]),
      child: Text(
        "Container",
        style: TextStyle(fontSize: 20),
      ),
    );
  }
}

• 约束宽高的布局

import 'package:flutter/material.dart';
class ContainerConstraints extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      //容器
      color: Colors.blue,
      width: 200,
      height: 200,
      constraints: BoxConstraints(
          minWidth: 100, maxWidth: 150,
          minHeight: 20, maxHeight: 100),
    );
  }
}