@8.20, 21

//debug release profile
//assets file binary network
//container
// Material , Cupertino
//Stateless .Stateful
//row column wrap container stack
//listview gridview

import 'package:flutter/material.dart';

//asset file network memory
void main() {
  runApp(const MaterialApp(debugShowCheckedModeBanner: false, home: Home()));
}
//List ListView.builder() ListView.separeate()
class Home extends StatelessWidget {
  const Home({Key? key}) : super(key: key);
 //positioned
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Stack Lesson'),
      ),
      body: GridView.builder(
        padding: EdgeInsets.all(8),
        itemCount: 1000,
        gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
          crossAxisCount: 3,
          mainAxisSpacing: 8,
          crossAxisSpacing: 8,
          childAspectRatio: 2/3
        ),
        itemBuilder: (BuildContext context, int index) {
          return Container(
            padding: const EdgeInsets.all(3),
            color: Colors.grey,
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Text('Person $index'),
                const Divider(color: Colors.white,),
                const Icon(Icons.person),
                const Divider(color: Colors.white,),
                ElevatedButton(onPressed: (){
                  _showSnackBar(context, "You followed Person $index");
                }, child: const Text('Follow'))
              ],
            ),
          );
        },


      )
    );
  }
  Widget _profile(BuildContext context,int position){
    debugPrint('ui is building $position');
   return Column(
     children: [
       ListTile(
         onTap: (){
           _showSnackBar(context, 'Person $position');
         },
         leading: const Icon(Icons.person),
         title: Text('Person $position'),
         subtitle: Text('Address $position'),
         trailing: (position %2 == 0) ? const Icon(Icons.phone) : const Icon(Icons.email),
       ),
       const Divider(height: 4,thickness: 3,),
     ],
   );
  }
  void _showSnackBar(BuildContext context,String text){
    ScaffoldMessenger.of(context)
        .showSnackBar(SnackBar(content: Text(text)));
  }
}