Call javascript function after script is loaded

To call a js function after load a script we can use the function loadScript()

To display a sweet-alert with html code use the function as shown below  

 loadScript: function(url, callback) {
              

            var sweetalert = '<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/sweetalert/1.1.3/sweetalert.min.css">'

            $('head').append(sweetalert);

            var script = document.createElement("script")
            script.type = "text/javascript";
            if (script.readyState) { // only required for IE <9
                script.onreadystatechange = function() {
                    if (script.readyState === "loaded" || script.readyState === "complete") {
                        script.onreadystatechange = null;
                        callback();
                    }
                };
            } else { //Others
                script.onload = function() {
                    callback();
                };
            }

            script.src = url;

            document.getElementsByTagName("head")[0].appendChild(script);
            
        },

 self.loadScript('https://cdnjs.cloudflare.com/ajax/libs/sweetalert/1.1.3/sweetalert.min.js', function() {

                    swal({
                        title: "",
                        text: "PREVIEW NOT AVAILABLE FOR THIS SELECTION",
                        icon: "warning",
                        confirmButtonColor: 'black',

                    })
                   self.render();
                })