Flutter开发:Gridview的使用

2022-04-12 16:38:46 浏览数 (1)

Flutter开发中,表格组件是经常要用到的,表格展示数据也是App开发过程中不可缺少的需求的功能,其实Gridview的属性和ListView的属性很接近,那么本篇文章就来聊聊Flutter开发中表格组件Gridview的简单使用。

Gridview常用的几种方式:

1、GridView.count(@required int crossAxisCount)

GridView.count的使用,需要传的是int类型的参数,也就是创建固定数量的item,crossAxisCount表示横轴item的个数(系统默认是横轴);

2、GridView.extent(@required double maxCrossAxisExtent)

GridView.extent的使用,需要传的是double类型的参数,也就是创建横轴上最大可容纳的item,maxCrossAxisExtent表示横轴item的最大宽度;

3、GridView.builder(@required this.gridDelegate,@required IndexedWidgetBuilder itemBuilder)

适用于widget数量多的时候,通过GridView.builder的使用,动态的创建widget,itemBuilder表示子widget构造器;

4、GridView.custom(@required this.gridDelegate,@required this.childrenDelegate)

GridView.custom的使用,通过两个代理方法gridDelegate和childrenDelegate来创建Gridview,其中gridDelegate是进行布局的代理,控制每列或每行的子widget的数量,以及上下左右间距和宽高比例;childrenDelegate的代理方法有两种实现方式,在使用的时候需要注意二者的区别。

Gridview的简单使用的实例,具体操作如下所示:

1、dart文件的具体实现源码

代码语言:javascript复制
import 'package:flutter/material.dart';
import 'package:portal/model/workspace_item_data.dart';
import 'package:portal/widgets/widget_warpper.dart';

class WorkspacePage extends StatefulWidget {
  @override
  _WorkspacePageState createState() => _WorkspacePageState();
}

class _WorkspacePageState extends State<WorkspacePage> {

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: buildAppBar(context, title: "工作台", leading: Container()),
      body: GridView.builder(
        itemCount: listData.length,
        gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
            crossAxisCount: 3, mainAxisSpacing: 10, crossAxisSpacing: 10, childAspectRatio: 0.9),
        padding: EdgeInsets.all(10),
        itemBuilder: getItem,
      ),
    );
  }
  Widget getItem(context, index) {
    return Container(
      decoration:
      BoxDecoration(border: Border.all(color: Colors.black12, width: 2)),
      child: Column(
        children: [
          Image.network(listData[index]['imageUrl']),
          SizedBox(
            height: 10,
          ),
          Text(listData[index]['title'])
        ],
      ),
    );
  }
}

2、数据源文件,Gridview的itemCount的数据源(为了体现列表效果,刻意多造了几条数据):

代码语言:javascript复制
List listData=[
  {
    "title": '行政审批',
    "author": 'Mohamed Chahin',
    "imageUrl": 'https://www.itying.com/images/flutter/1.png',
  },
  {
    "title": '协同办公',
    "author": 'Google',
    "imageUrl": 'https://www.itying.com/images/flutter/2.png',
  },
  {
    "title": '实名认证',
    "author": 'Alibaba',
    "imageUrl": 'https://www.itying.com/images/flutter/3.png',
  },
  {
    "title": '会议室',
    "author": 'Mohamed Chahin',
    "imageUrl": 'https://www.itying.com/images/flutter/4.png',
  },
  {
    "title": '企业邮箱',
    "author": 'Mohamed Chahin',
    "imageUrl": 'https://www.itying.com/images/flutter/5.png',
  },
  {
    "title": '测温',
    "author": 'Mohamed Chahin',
    "imageUrl": 'https://www.itying.com/images/flutter/6.png',
  },
  {
    "title": '企业文化',
    "author": 'Mohamed Chahin',
    "imageUrl": 'https://www.itying.com/images/flutter/7.png',
  },];

3、效果图如下所示:

0 人点赞