gistfile1.js

$('body').on('keyup.search', function(e) {
    if ($('#search-dropdown').is(':visible')) {
        console.log(e.which);

        var selectedIndex = Discourse.__container__.lookup("controller:search").get("selectedIndex");
        var lastIndex = Discourse.__container__.lookup("controller:search").get("lastIndex");

        if (e.which == 9) {

            if (document.activeElement) {
                selectedElementId = document.activeElement.parentElement.id; //focused element id

                if (Ember.View.views.hasOwnProperty(selectedElementId)) { //check if we have an emberview with that id. if yes we assume it is a search result item
                    var ElementIndex = Ember.View.views[document.activeElement.parentElement.id].content.index; //get the element index 
                    Discourse.__container__.lookup("controller:search").set("selectedIndex", ElementIndex); //and set the item to be selected
                } else { //if the element in focus is not a search result. probably a show more, unselect the selected item
                    var lastIndex = Discourse.__container__.lookup("controller:search").get("selectedIndex");
                    Discourse.__container__.lookup("controller:search").set("lastIndex", lastIndex);
                    Discourse.__container__.lookup("controller:search").set("selectedIndex", -1);
                }
            }


        } else if (e.which == 13) { //allow click on "show more" or "(x)" button in the view

            if (document.activeElement.classList.contains("filter")) {
                $(document.activeElement).click();
            }

        } else if (e.which == 38) { //arrow up/down restore from unselected mode
            if (selectedIndex == -1) {
                Discourse.__container__.lookup("controller:search").set("selectedIndex", lastIndex);
            }
            if (document.activeElement != $("#search-term")[0]) { //make sure search input is selected if the user stopped using tab navigation
                $("#search-term").focus(); //assure focus on input
                Discourse.__container__.lookup("controller:search").set("selectedIndex", lastIndex); //TODO in some cases lastIndex will no be most up to date and it can we when se it to selected again
            }

        } else if (e.which == 40) {
            if (selectedIndex == -1) {
                if (lastIndex == 0) lastIndex = 1;
                Discourse.__container__.lookup("controller:search").set("selectedIndex", lastIndex - 1);

            }
            if (document.activeElement != $("#search-term")[0]) { //make sure search input is selected if the user stopped using tab navigation
                $("#search-term").focus(); //assure focus on input
                Discourse.__container__.lookup("controller:search").set("selectedIndex", lastIndex);
            }
        }
    }
});