projects built with vue cli are mounted in < div id="app" > div > 
 in template, and in the entry file of webpack: 
const app = new Vue({
  el: "-sharpapp",
  data: {
       text: "" 
  },
});
want to use a method in template to change the value of data and update the view. Used
document.getElementById ("change"). Onclick = function () {
Vue.set(app.$data,"text","")} 
 value can be changed, but the view has not been updated. Is there any way to update the view? 
