Code for expansion panel

expansion_panel_part.dart

    return ExpansionPanelList(
      expansionCallback: (int index, bool isExpanded) {
        setState(() {
            isExpanded1 = !isExpanded;
        });
      },
      children: gridTiles.map<ExpansionPanel>((tile) {
        return ExpansionPanel(
          body: Text("test body"),
          headerBuilder: (BuildContext context, bool isExpanded) {
            return ListTile(
              leading: Icon(Icons.title),
              title: Text("test"),
              onTap: () => print("Test"),
            );
          },
          canTapOnHeader: true,
          isExpanded: isExpanded1,
        );
      }).toList(),
    );