flutter_gridview_tut

.\lib\main.dart

import 'package:flutter/material.dart';
import 'package:transparent_image/transparent_image.dart';
//...
class _MyHomePageState extends State<MyHomePage> {
  //...
  Widget _gridList() {
    return GridView.builder(
      itemCount: 60,
      gridDelegate:
          SliverGridDelegateWithFixedCrossAxisCount(crossAxisCount: 4),
      itemBuilder: (context, index) {
        return Padding(
          padding: const EdgeInsets.all(3.0),
          child: GestureDetector(
            child: FadeInImage.memoryNetwork(
                placeholder: kTransparentImage,
                image: 'https://picsum.photos/id/$index/128'),
            onTap: () {
              _openImage(context, index);
            },
          ),
        );
      },
    );
  }
}