How get selected index of ListView and ListTile of multiple submenus sidebar?

Question

How get selected index of ListView and ListTile of multiple submenu's sidebar in Flutter?

This is my code:

class _SidebarState extends State<Sidebar> {
  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        ListTile(
          title: Text(
            'test',
            style: TextStyle(color: Colors.lightBlue),
          ),
          leading: Icon(
            Icons.keyboard_command_key,
            size: 40,
            color: Colors.lightBlue,
          ),
        ),
        SizedBox(
          height: 50,
        ),
        Expanded(
          child: ListView(
            children: basictiles.map(buildTile).toList(),
          ),
        ),
      ],
    );
  }

  Widget buildTile(BasicTile tile, {double leftPadding = 16}) {
    if (tile.tiles.isEmpty) {
      return ListTile(
        leading: tile.icon,
        contentPadding: EdgeInsets.only(left: leftPadding),
        title: Text(tile.title),
      );
    } else {
      return ExpansionTile(
        tilePadding: EdgeInsets.only(left: leftPadding),
        leading: tile.icon,
        title: Text(tile.title),
        children: tile.tiles
            .map((tile) => buildTile(tile, leftPadding: 16 + leftPadding))
            .toList(),
      );
    }
  }
}

How get selected index of ListView and ListTile of multiple submenus sidebar in Flutter?

Answer 1

You can use the index for loop as following.

@override
  Widget build(BuildContext context) {
    return Material(
      child: Column(
        children: [
          ListTile(
            title: Text(
              'test',
              style: TextStyle(color: Colors.lightBlue),
            ),
            leading: Icon(
              Icons.keyboard_command_key,
              size: 40,
              color: Colors.lightBlue,
            ),
          ),
          SizedBox(height: 50),
          Expanded(
            child: ListView(
              children: [
                for (var i = 0; i < basictiles.length; i++)
                  buildTile(basictiles[i], i),
              ],
              // children: basictiles.map(buildTile).toList(),
            ),
          ),
        ],
      ),
    );
  }
Widget buildTile(BasicTile tile, int mainIndex, {double leftPadding = 16}) {
    if (tile.tiles.isEmpty) {
      return ListTile(
        leading: tile.icon,
        contentPadding: EdgeInsets.only(left: leftPadding),
        title: Text(tile.title),
      );
    } else {
      return ExpansionTile(
        tilePadding: EdgeInsets.only(left: leftPadding),
        leading: tile.icon,
        title: Text(tile.title),
        children: [
          for (var i = 0; i < tile.tiles.length; i++)
            GestureDetector(
              onTap: () {
                print('Main Index: $mainIndex');
                print('Sub Index: $i');
              },
              child: buildTile(tile.tiles[i], i, leftPadding: 16+leftPadding),
            )
        ],
      );
    }
  }