$(document).ready(function () {
    var tree = $('#listagem_cadastro_menu').tree({
        primaryKey: 'id',
        uiLibrary: 'materialicons',
        iconsLibrary: 'materialicons',
        dataSource: '/Permissao/Get',
        params: { NivelID: @ViewBag.ID},
        checkboxes: true,
        icons: {
            expand: '<i class="material-icons">keyboard_arrow_right</i>',
            collapse: '<i class="material-icons">keyboard_arrow_right</i>',
        },
    });

    tree.on('checkboxChange', function (e, $node, record, state) {
         // alert('record ' + JSON.stringify(record));
        //alert('node ' + JSON.stringify($node))
        //alert('state ' + JSON.stringify(e))
        //alert(record.checked);
        atualizaPermissao(record.id, record.checked);

    });

    function atualizaPermissao(MenuID, checked) {
        $.ajax({
            url: "/Permissao/SaveCheckedNode",
            data: { NivelID: @ViewBag.ID, MenuID: MenuID, checked: checked },
            dataType: "json",
            method: 'POST',
           }
        )
            .fail(function () {
                alert('Failed to save.');
        });
    }
   });

[HttpPost]
    public JsonResult SaveCheckedNode (int NivelID, int MenuID, bool @checked)
    {

        if (@checked == true)
        {
                var Menus = db.MENUs.Find(MenuID);
                var Nivel = db.NIVELs.Find(NivelID);

                Menus.NIVELs.Add(Nivel);
                db.Entry(Menus).State = System.Data.Entity.EntityState.Modified;
                db.SaveChanges();
        }
        else if (@checked == false)
        {
                var Menus = db.MENUs.Find(MenuID);
                var Nivel = db.NIVELs.Find(NivelID);

                Menus.NIVELs.Remove(Nivel);
                db.Entry(Menus).State = System.Data.Entity.EntityState.Modified;
                db.SaveChanges();
        }
        return Json(@checked, JsonRequestBehavior.AllowGet);
    }