Interactive Grid "Add Row" generate In the last section

In the last section, you want to generate a row in the Grid region.
So you can follow the steps.

Go to 
Function and Global Variable Declaration :

function f_add_row_last() {

    var row$;

    var region = apex.region('tots');

    var view = region.call("getCurrentView");

    if (view.internalIdentifier === "grid") {

        row$ = region.widget().find(".a-GV-row").last();

        view.view$.grid("setSelection", row$);

        region.call("getActions").invoke("selection-add-row");

    }

}

Select  Grid region then Static ID: tots

Go to Grid region attributes then
Go to  Initialization JavaScript Function and paste the following code:

function(config) {

    let $ = apex.jQuery,

        toolbarData = $.apex.interactiveGrid.copyDefaultToolbar();

    // toolbarGroup = toolbarData.toolbarRemove("actions2");

    toolbarGroup = toolbarData.toolbarRemove("actions3");

    toolbarData.push(

        {

            groupTogether: false,

            align: "start",

            controls: [

                {

                    type: "BUTTON",

                    action: "addrow",

                    id: "saveid",

                    label: "Add Row",

                    hot: true

                }

            ]

        }

    );

    config.initActions = function (actions) {

        actions.add({

            name: "addrow",

            action: function () {

               f_add_row_last();

            },

        });

    }

    config.toolbarData = toolbarData;

    return config;

}