Question

I have a searchable textbox which populates a div with the search results. The div is scrollable. What I am trying to achieve, is to navigate through the result items with page up and down (keycode 38 & 40). But as soon as I try this, the whole div scrolls, and the result item itself does not take on the new selected css class.

Below is some of my code

this.TagNavigation = function (event) {
    var div = $("#TagSearchResults");
    var anchors = $("#TagSearchResults a");
    var selectedAnchor = $("#TagSearchResults a.selected");
    var position = anchors.index(selectedAnchor);

        if (event.keyCode == "13" && anchors.length > 0) {
            FRAMEWORK.AddUpdateInterventionTags(selectedAnchor.attr("id").split("-")[1] + "|" + selectedAnchor.text(), "add");
        }
        if (event.keyCode == "13" && anchors.length == 0 && $("#txtTagSearch").val() != "Start typing to search Tags") {
            FRAMEWORK.AddNewTag($("#txtTagSearch").val());
        }
        else if (event.keyCode == "38") {

            if (position > 0) {
                canClose = false;
                selectedAnchor.removeClass("selected");
                var newSelectedAnchor = $(anchors.get(position - 1));
                newSelectedAnchor.addClass("selected");
                $("#txtTagSearch").val(newSelectedAnchor.text());
            }
        }
        else if (event.keyCode == "40") {

            if (position <= anchors.length) {
                canClose = false;
                selectedAnchor.removeClass("selected");
                var newSelectedAnchor = $(anchors.get(position + 1));
                newSelectedAnchor.addClass("selected");
                $("#txtTagSearch").val(newSelectedAnchor.text());
                //newSelectedAnchor.focus();
            }
        }
    };

    this.AjaxSearch = function (text) {
        var div = $("#TagSearchResults");
        var anchors = $("#TagSearchResults a");
        var selectedAnchor = $("#TagSearchResults a.selected");
        var position = anchors.index(selectedAnchor);

        if (event.keyCode == "13") {
            FRAMEWORK.TagNavigation(event);
        }
        else if (event.keyCode == "38") {
            FRAMEWORK.TagNavigation(event);
        }
        else if (event.keyCode == "40") {
            FRAMEWORK.TagNavigation(event);
        }
        else if (text.length >= 3) {
            FRAMEWORK.RenderSearchResults(text);
        }
        else {
            $("#TagSearchResults").html("");
            $("#TagSearchResults").hide();
        }
    };

As you can see in the TagNavigation function (keycode 40), I tried to set the focus on the active element, but still no success.

Any help please.

Answer 1

You need to check weather the newly selected element has a higher Y value that the bottom of the containing div. If so, then scroll the div by the height of the new element. Change your ‘if (event.keyCode == “40”)’ statement to the following:

this.TagNavigation = function (event) {
        var div = $("#TagSearchResults");
        var anchors = $("#TagSearchResults a");
        var selectedAnchor = $("#TagSearchResults a.selected");
        var position = anchors.index(selectedAnchor);

        if (event.keyCode == "13" && anchors.length > 0) {
            FRAMEWORK.AddUpdateInterventionTags(selectedAnchor.attr("id").split("-")[1] + "|" + selectedAnchor.text(), "add");
        }
        if (event.keyCode == "13" && anchors.length == 0 && $("#txtTagSearch").val() != "Start typing to search Tags") {
            FRAMEWORK.AddNewTag($("#txtTagSearch").val());
        }
        else if (event.keyCode == "38") {

            if (position > 0) {
                canClose = false;
                selectedAnchor.removeClass("selected");
                var newSelectedAnchor = $(anchors.get(position - 1));
                newSelectedAnchor.addClass("selected");
                $("#txtTagSearch").val(newSelectedAnchor.text());
                var newSelectedAnchorPosistion = newSelectedAnchor.offset();
                var divPosition = div.offset();
                divPosition = divPosition.top;
                if (newSelectedAnchorPosistion.top + 1 > divPosition) {
                    var newPos = div.scrollTop() - newSelectedAnchor.outerHeight();
                    div.scrollTop(newPos);
                }
            }
        }
        else if (event.keyCode == "40") {
            if (position < anchors.length - 1) {
                canClose = false;
                selectedAnchor.removeClass("selected");
                var newSelectedAnchor = $(anchors.get(position + 1));
                newSelectedAnchor.addClass("selected");
                $("#txtTagSearch").val(newSelectedAnchor.text());
                var newSelectedAnchorPosistion = newSelectedAnchor.offset();
                var divPosition = div.offset();
                divPosition = divPosition.top + div.outerHeight();
                if (newSelectedAnchorPosistion.top + 1 >= divPosition) {
                    var newPos = div.scrollTop() + newSelectedAnchor.outerHeight();
                    div.scrollTop(newPos);
                }
            }
        }
    };