vue.js put focus on input

Question

HTML

<span :style="{ display : displayTitle }" @dblclick="showInput()">
  {{ node.title }}
</span>
<input :style="{ display : displayTitleInput }" type="text" 
       @blur="hideInput1" @keydown="hideInput2" 
       @input="changeTitle(node.id , $event.target.value)" 
       :value="node.title">

JS

data() {
  return {
      displayTitle: "inline-block",
      displayTitleInput: "none"
    };
},
showInput() {
    this.displayTitle = "none"
    this.displayTitleInput = "inline-block"
},
hideInput1() {
   this.displayTitle = "inline-block"
   this.displayTitleInput = "none"
},
hideInput2(event) {
    if (event.keyCode === 13) {
        this.hideInput1()
    }
},

I am a beginner Japanese web developer. I am not good at English, sorry.

HTML is in "v-for" (v-for="node in list").

When double click text, it turns to <input>.

I want to make it possible to focus on input when it appears.

I tried this but it didn't work.

HTML

<span :style="{ display : displayTitle }" @dblclick="showInput(node.id)">
  {{ node.title }}
</span>
<input :ref='"input_" + node.id' :style="{display:displayTitleInput}" type="text" 
       @blur="hideInput1" @keydown="hideInput2" 
       @input="changeTitle(node.id , $event.target.value)" 
       :value="node.title">

JS

showInput(id) {
    this.displayTitle = "none"
    this.displayTitleInput = "inline-block"

    this.$nextTick(this.$refs["input_" + id][0].focus())
},

There was no error on console, but didn't work.

Answer 1

Your primary problem is that $nextTick takes a callback function but you are executing

this.$refs["input_" + id][0].focus()

immediately. You could get your code working correctly with

this.$nextTick(() => {
  this.$refs["input_" + id][0].focus()
})

However, I think you'll run in to further problems and your code can be made much simpler.

One problem you'll find is that all your node inputs will become visible when double-clicking on any of them due to your style rules.

You could instead store an "editing" flag somewhere either on the node or in a separate object.

Below is an example that simplifies your code by...

1. Using the array-like nature of ref when used within a v-for loop, and
2. Using the enter modifier on your @keydown event binding

new Vue({
  el: '#app',
  data: {
    list: [
      {id: 1, title: 'Node #1'},
      {id: 2, title: 'Node #2'}
    ],
    editing: {}
  },
  methods: {
    showInput(id, index) {
      this.$set(this.editing, id, true)
      
      this.$nextTick(() => {
        this.$refs.input[index].focus()
      })
    },
    hideInput(id) {
      this.editing[id] = false
    }
  }
})

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.6.10/vue.min.js"></script>
<ul id="app">
  <li v-for="(node, index) in list">
    <span v-show="!editing[node.id]" @dblclick="showInput(node.id, index)">
      {{ node.title }}
    </span>
    <input v-show="editing[node.id]" type="text"
           ref="input" :value="node.title"
           @blur="hideInput(node.id)" @keydown.enter="hideInput(node.id)">
  </li>
</ul>

Answer 2

The way you use this.$nextTick(); is incorrect. You should pass it a callback function.

this.$nextTick(function () {
    this.$refs["input_" + id].focus()
})

https://jsfiddle.net/un65e9oc/7/

---

I'm not however sure how that array access is working for you, because as I notice, $refs is an object with the keys referring to the ref name.

[Edit: Thanks to @Phil's comment, above is clear.]

---

The above is the correct solution for your problem. Since you have already got that answer, I'll add something other than that.

The reason why you see this behavior is that because the reference you hold in $refs doesn't get updated when you change the visibility of the text box in your showInput() method. So when you call this.$refs["input_" + id].focus();, it's actually trying to set focus on a hidden element (because the current reference is not updated).

That's why you need to call the $nextTick() to update it. But if you wanted a quick fix to your problem, without calling $nextTick(), you could update it manually like this:

this.displayTitleInput = "inline-block"
this.$refs["input_" + id].style.display = this.displayTitleInput

this.$refs["input_" + id].focus();

This would also work :) Hope it helps!!