Variation of the GridView_Demo

gridview_demo02.dart

//
//   https://fluttercentral.com/Articles/Post/45
//
//   Author: Seven Srikanth 
//
//   Modified: Greg Perry
//
import 'package:flutter/material.dart';

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // TODO: implement build
    return MaterialApp(
      home: DefaultTabController(
          length: 5,
          child: Scaffold(
              appBar: AppBar(
                  title: Text('Grid Demo'),
                  bottom: TabBar(
                    tabs: [
                      Tab(
                        text: 'GridView',
                      ),
                      Tab(
                        text: 'GridView.Count',
                      ),
                      Tab(
                        text: 'GridView.builder',
                      ),
                      Tab(
                        text: 'GridView.custom',
                      ),
                      Tab(
                        text: 'GridView.extent',
                      ),
                    ],
                    isScrollable: true,
                  )),
              body: TabBarView(children: [
                GridView(
                  gridDelegate: SliverGridDelegateWithMaxCrossAxisExtent(
                      maxCrossAxisExtent: 200.0),
                  children: List.generate(100, sampleContainer),
                ),
                GridView.count(
                    crossAxisCount: 3,
                    children: List.generate(100, sampleContainer)),
                GridView.builder(
                  itemCount: 100,
                  gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
                      crossAxisCount: 3),
                  itemBuilder: (_, int index) {
                    return sampleContainer(index);
                  },
                ),
                GridView.custom(
                    gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
                        crossAxisCount: 3),
                    childrenDelegate:
                    SliverChildListDelegate(List.generate(100, sampleContainer))),
                GridView.extent(
                  maxCrossAxisExtent: 200.0,
                  children: List.generate(100, sampleContainer),
                )
              ]))),
    );
  }

  Widget Function(int index) sampleContainer = (index) {
    return Container(
      padding: EdgeInsets.all(20.0),
      child: Center(
        child: GridTile(
          footer: Text(
            'Item $index',
            textAlign: TextAlign.center,
          ),
          header: Text(
            'SubItem $index',
            textAlign: TextAlign.center,
          ),
          child: Icon(Icons.access_alarm,
              size: 40.0, color: Colors.white30),
        ),
      ),
      color: Colors.blue[400],
      margin: EdgeInsets.all(1.0),
    );
  };
}

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