how can i get ref for every grid-item while using react-grid-layout

Question

i am trying to use react-grid-layout to draw my page. while getting each ref for grid-item, i get some trouble.. here is my code

      <ReactGridLayout
        layout={layout}
        {...{
          className: "layout",
          items: 10,
          cols: 8,
          rowHeight: 12,
          verticalCompact: false,

          isDraggable: false,
        }}
      >
        {eles.map((item) => {
          return (
            <div
              key={item.key}
              ref={(el) => {
                itemsEls.current[item.key] = el;
              }}
            >
              {item.key}
            </div>
          );
        })}
      </ReactGridLayout>

i have searched a lot...i got an answer from this question but i dont know how it works...