get access to selected row data from outside table component

What you can do is pass maintain some state for selectedRows in you parent component then pass a callback to Table component that'll be called every time a row is selected or unselected. Here I have made some changes to your sandbox, hope it helps :)

https://codesandbox.io/s/naughty-sun-3nhue?file=/src/App.js

@jiltender 

    i fix my problem by doing this to get row data outside the table 
    
        rowProps={row =>(console.log(row)
                )} 
        

add this on parent components where u call the Table 
     <Table
            sortByProps={[]}
            columns={columns}
            rowProps={row =>(setSelectedItems(row))}  /// pass row props
           
          />
    
and the table side 
add this in 
function props 
` `rowProps = () => ({}) }) 

    function Table({ columns, data, showSpinnerProp, hiddenColumnsProps,getCellProps, getRowProps, height, sortByProps, source, 

    setSelectedItems,rowProps = () => ({}) }) {
        
        this will return u all the select data  you can call it before return 
        useEffect(() => {
            setSelectedItems = selectedFlatRows;
            rowProps(selectedFlatRows)
          }, [selectedFlatRows]);
        
        }