flutter: LateInitializationError: Field '_children@37042623' has not been initialized

Question

I use StaggeredGrid Widget but it's showing errors "LateInitializationError: Field '_children@37042623' has not been initialized".

ERROR:

LateInitializationError: Field '_children@37042623' has not been initialized

MY CODE:

Widget build(BuildContext context) {
    return Scaffold(
        body: StaggeredGrid.count(
            crossAxisCount: 4,
            mainAxisSpacing: 4,
            crossAxisSpacing: 4,
            children: [
          StaggeredGridTile.count(
            crossAxisCellCount: 2,
            mainAxisCellCount: 2,
            child: Container(
              child: Text("abc"),
            ),
          ),
          StaggeredGridTile.count(
            crossAxisCellCount: 2,
            mainAxisCellCount: 1,
            child: Container(
              child: Text("abc"),
            ),
          ),
          StaggeredGridTile.count(
            crossAxisCellCount: 1,
            mainAxisCellCount: 1,
            child: Container(
              child: Text("abc"),
            ),
          ),
          StaggeredGridTile.count(
            crossAxisCellCount: 1,
            mainAxisCellCount: 1,
            child: Container(
              child: Text("abc"),
            ),
          ),
          StaggeredGridTile.count(
            crossAxisCellCount: 4,
            mainAxisCellCount: 2,
            child: Container(
              child: Text("abc"),
            ),
          ),
        ]));
  }