Delay Search only partially working

egglesworth

I am using DT within an RShiny app with a large datatable. I am using a regex search for character columns, so it takes 2 or 3 seconds for each search. I therefore put in a delay search, but it seems to be triggering once with the first letter of the search, as per this question.

Is there a solution (or a workaround that would work in RShiny?)

https://datatables.net/forums/discussion/37988/option-searchdelay-triggering-once-before-specified-delay

rf1234

Have you seen throttled search? Here is an example from my own coding with a delay of 1 second, if I recall it correctly:

https://datatables.net/reference/api/DataTable.util.throttle()

$('.filterHead', ctrTable.table().header()).each( function (i) {
    var title = (lang === 'de' ? 'Suche ' : 'Search ') + $(this).text();
    var column = ctrTable.column(i);
    var throttledSearch = $.fn.dataTable.util.throttle(                        
        function (e) {
            var code = e.which;
        // 8: backspace, 46: delete, 13: enter, 32: space, 
        // 59 or 186: semi-colon,
        // 188: comma, 189: dash or minus, 190: period
            if ( code == 13 ) { //enter key
                e.preventDefault();
            }
            var txt = $(this).val();
            if ( txt.length > 1 || code == 8 || code == 46 ) {
                column
                    .search(txt)
                    .draw();
            }
        },
        1000
    );
    $('<input type="text" placeholder="'+title+'" class="text-muted"/>')
        .appendTo( $(this).empty() )
        .on( 'keyup change', throttledSearch); 
} ); 

allan

Hi,

This is sort of intended - the idea was to start a process as soon as the user does some kind of interaction, and then debounce from there. In retrospect that was a mistake, we should just do a delay debounce rather than a throttle. I plan to change that for v2, but wasn't planning to change it before.

It would require a tweak in the DataTables source if you wanted to make that change before then.

Allan

rf1234

@allan, thanks for clarifying. I had found out that searchDelay isn't working too - and got a combination of searchDelay and throttled search running.

egglesworth

Thanks for the responses - is there a way to get the above to work in R Shiny?