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                <div id="app" v-cloak class="container mx-auto flex items-center flex-col mt-10">
  <header class="text-center">
    <h1 class="text-5xl font-black">To do list on Vue.js</h1>
    <p class="text-xl font-semibold mb-8">You have {{ items.length }} tasks.</p>

  <main class="mt-3">
    <label for="">
      <input id="add_item" type="text" placeholder="Add task" autofocus ref="addtask"
             class="bg-gray-200 focus:bg-white border-black border-solid border-2 px-2 py-1 w-full mb-4 hover:bg-white"
             @keyup.enter="addItem" />

    <ul class="max-w-xs">
      <li v-for="(item, index) in items" class="my-4 flex items-center justify-end">
        <span v-if="! item.edit" class="px-2 py-1 mr-2 w-40 border-transparent border-solid border-2 hover:border-black" @click="enableEdit(index)">{{ item.title }}</span>
        <input v-else type="text" v-model="item.title" :ref="'task'" @keyup.enter="disableEdit(index)" @blur="disableEdit(index)" class="px-2 py-1 mr-2 w-40 border-black border-transparent focus:border-black border-solid border-2 focus:bg-white">
        <button class="border-black border-solid border-2 bg-orange-400 hover:bg-black hover:text-orange-400 focus:bg-black focus:text-orange-400 px-2 py-1 mr-2" @click="removeItem(index)">Delete</button>
        <button class="border-black border-solid border-2 bg-blue-400 hover:bg-black hover:text-blue-400 focus:bg-black focus:text-blue-400 px-2 py-1" @click="enableEdit(index)">Edit</button>

    <p class="error px-2 py-1 rounded" v-if="isError">☝This task already exists.</p>

  <div class="flex items-center bg-blue-500 text-white text-sm font-bold px-4 py-3 mt-12" role="alert">
  <svg class="fill-current w-4 h-4 mr-2" xmlns="" viewBox="0 0 20 20"><path d="M12.432 0c1.34 0 2.01.912 2.01 1.957 0 1.305-1.164 2.512-2.679 2.512-1.269 0-2.009-.75-1.974-1.99C9.789 1.436 10.67 0 12.432 0zM8.309 20c-1.058 0-1.833-.652-1.093-3.524l1.214-5.092c.211-.814.246-1.141 0-1.141-.317 0-1.689.562-2.502 1.117l-.528-.88c2.572-2.186 5.531-3.467 6.801-3.467 1.057 0 1.233 1.273.705 3.23l-1.391 5.352c-.246.945-.141 1.271.106 1.271.317 0 1.357-.392 2.379-1.207l.6.814C12.098 19.02 9.365 20 8.309 20z"/></svg>
  <p>PWA version <a href="" target="_blank" rel="noreferrer noopeneer" class="underline">here</a></p>

  <!-- <pre>{{ $data }}</pre> -->


                [v-cloak] {
  display: none;

*::before {
  transition: all 0.25s ease-out;



                new Vue({
  el: "#app",
  data() {
    return {
      items: [
          title: "HTML5",
          edit: false
          title: "CSS3",
          edit: false
          title: "JavaScript",
          edit: false
      taskItem: "",
      isError: false
  methods: {
    addItem: function(e) {
      value =;

      if (value === "") {
        return false;

      if (this.itemExist(value) === true) {
        let repeated = []
          function(span) {
            return span.textContent === value;
        this.isError = true;
        return false;

      this.isError = false; = "";
        title: value,
        edit: false

      let repeatedClasses = document.querySelectorAll(".bg-orange-300");
      for (let repeatedClass of repeatedClasses) {
    removeItem: function(index) {
      this.items.splice(index, 1);
    enableEdit: function(index) {
      this.items[index].edit = true;
      this.$nextTick(() => {
        let input = this.$refs.task[0];
    disableEdit: function(index) {
      this.items[index].edit = false;
    itemExist: function(value) {
      for (var i = 0; i < this.items.length; i++) {
        if (this.items[i].title === value) {
          return true;

      return false;