创建一个网格列表

有时候，你可能希望用网格来展示内容，而不是一条接着一条的普通列表来展示。在本文当中，我们将采用 GridView widget。

In some cases, you might want to display your items as a grid rather than a normal list of items that come one after the next. For this task, use the GridView widget.

用网格展示数据最简单的方式，就是通过使用 GridView.count() 构造方法，因为它允许我们指定有多少行多少列。

The simplest way to get started using grids is by using the GridView.count() constructor, because it allows you to specify how many rows or columns you’d like.

为了帮助我们想象 GridView 是如何工作的，在这个例子中，我们将创建一个包含有 100 个 widget 的 List，每个 Widget 将展示它在 List 中的索引。

To visualize how GridView works, generate a list of 100 widgets that display their index in the list.

GridView.count(
  // Create a grid with 2 columns. If you change the scrollDirection to
  // horizontal, this produces 2 rows.
  crossAxisCount: 2,
  // Generate 100 widgets that display their index in the List.
  children: List.generate(100, (index) {
    return Center(
      child: Text(
        'Item $index',
        style: Theme.of(context).textTheme.headline,
      ),
    );
  }),
);

交互式样例

Interactive example

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final title = 'Grid List';

    return MaterialApp(
      title: title,
      home: Scaffold(
        appBar: AppBar(
          title: Text(title),
        ),
        body: GridView.count(
          // Create a grid with 2 columns. If you change the scrollDirection to
          // horizontal, this produces 2 rows.
          crossAxisCount: 2,
          // Generate 100 widgets that display their index in the List.
          children: List.generate(100, (index) {
            return Center(
              child: Text(
                'Item $index',
                style: Theme.of(context).textTheme.headline,
              ),
            );
          }),
        ),
      ),
    );
  }
}