how to get current sort order from tablesorter plugin?

Question

I'm just starting to use Christian Bach's excellent TableSorter plugin, and I need to get a column's current sort direction. I have several columns:

• ID
• Name
• Category

ID and Name are set to non-sortable using

headers:    { 0: {sorter: false}, 1: {sorter: false} }

I'm adding a click handler on Name so that it fires the sort event on the Category column. Using the example "Sort table using a link outside the table", I'm able to get the Name header to fire the Category sort -- but it's hard-coded to sort in one direction.

How can I get it to look at the current direction the Category column is currently sorted, and sort in the opposite direction? (I can handle flipping the values; since the sort order is 0 or 1, I can XOR the value to get the opposite, like var sort; sort ^= sort; -- my question is how to get the current value.

Here's the code that currently sets the click handler on the Name column:

$("#nameCol").click(function() {
    var sorting = [[2, 0]];     /* sort 3rd col (Category) descending */
    $("#SearchResults").trigger("sorton", [sorting] );  /* SearchResults is the ID of the sortable table */
    return false;               /* cancel default link action on a#nameCol */
});

Thanks!

Answer 1

The table headers should all call the same click event:

$('th').click(function() {
     handleHeaderClick(this);
});  

Then click handler should add/remove the applicable classes.

function handleHeaderClick(hdr) {
    if ($(hdr).hasClass('headerSortDown') == true) {
        $(hdr).removeClass('headerSortDown');
        $(hdr).addClass('headerSortUp');
    } else if ($(hdr).hasClass('headerSortUp') == true) {
        $(hdr).removeClass('headerSortUp');
        $(hdr).addClass('headerSortDown');
    } else {
        $('th', myTable).removeClass('headerSortUp headerSortDown');
        $(hdr).addClass('headerSortDown');
    }
    doSomething();
};

I hope this helps.

Answer 2

You can use the built in sortEnd event to get the sortOrder as explained here: https://stackoverflow.com/a/4150187/363155

$('#yourtableId').on('sortEnd', function(event) {
    // Prints the current sort order to the console
    console.log(event.target.config.sortList);
});

Answer 3

You can also capture it outside, anywhere else (e.g. in your function, start of ajax, ..), and only when needed and not on every click, with a bit less overhead like this:

lastSortList=$("#mytable")[0].config.sortList;

And example for sorting it back after ajax update:

$("#mytable").trigger("sorton", [lastSortList]);

Remember to declare the first line in the right scope though.

Answer 4

I wrote a function to save the current sort order. This helped me out in a situation where the table was being rebuilt from scratch.

function SaveSortOrder(tablename) {
//returns an array of a tablesorter sort order
var hdrorder = new Array();
var hdrs = $("#" + tablename + " th");
var arrayindex = 0;
hdrs.each(function (index) {
    if ($(this).hasClass('headerSortDown')) {
        hdrorder[arrayindex] = [index, 0];
        arrayindex++;
    }
    else if ($(this).hasClass('headerSortUp')) {
        hdrorder[arrayindex] = [index, 1];
        arrayindex++;
    }       
});

return hdrorder;
}