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Check if sub-menus are overflowing the viewport and adjust their horizontal positioning accordingly.

JavaScript February 7, 2021


This function runs automatically, so it is not called manually. Is this incorrect?

Additional Notes

This function checks the ID #primarynav for their first sub-menu automatically.

Source File

Located in /assets/js/modules/helpers.js on line 83.

No Hooks

This function does not have any filters or actions available. Request one?
nebula.overflowDetector = async function(){
    if ( jQuery('.sub-menu').length ){ //Only add the event listener if sub-menus actually exist
            'mouseenter focus focusin': function(){
                if ( jQuery(this).children('.sub-menu').length ){ //Check if this menu has sub-menus
                    let submenuLeft = jQuery(this).children('.sub-menu').offset().left; //Left side of the sub-menu
                    let submenuRight = submenuLeft+jQuery(this).children('.sub-menu').width(); //Right side of the sub-menu

                    if ( submenuRight > nebula.dom.window.width() ){ //If the right side is greater than the width of the viewport
                        jQuery(this).children('.sub-menu').addClass('overflowing overflowing-left');
                    } else if (submenuLeft > nebula.dom.window.width() ) {
                        jQuery(this).children('.sub-menu').addClass('overflowing overflowing-right');
                    } else {
                        jQuery(this).children('.sub-menu').removeClass('overflowing overflowing-left overflowing-right');
            'mouseleave': function(){


To override or disable this JavaScript function, simply redeclare it with the exact same function name.

nebula.overflowDetector = function(){
    //Write your own code here, leave it blank, or return false.