test.js

Row {
	handleMoveDown() {
		this.props.onChange(this.props.index, -1);
	}

	handleMoveUp() {
		this.props.onChange(this.props.index, 1);
	}
}



Group {
	handleReorder(index, numOfRows) {
		const newRowOrder = [...this.state.rows];

		// Manipulate newRowOrder here to move it +/- rows

		return newRowOrder
	}

	render() {
		return <div>
			{this.state.rows.map((item, i) => <Row index={i} onChange={this.handleReorder} />)}
		</div>
	}
}