Vue v-for loop - How To Target Component When Array is Filtered

Question

I am using a computed value to dynamically filter an array ("orders").

The computed .filter() function allows the user to dynamically search by order number, name or reference:

data() {
  return {
    orders: [],
    search: ""  // search string from a text input    
  };
},

computed: {
  filtered: 
    return this.orders.filter(order => {
      const s =
        order.order_number + order.reference + order.name;
      const su = s.toUpperCase();
      return su.match(this.search.toUpperCase());
    });
  }

I am using a v-for loop to render the search results as follows:

 <tbody v-for="(order, index) in filtered" :key="order.id">              
   <tr>       
     <td @click="add_events(order, index)>{{order.order_number}}</td>
     <td>{{order.reference}}</td>
     <td>{{order.name}}</td>
      ...
    </tr>
  </tbody>

I want to use the @click to target a specific component (an object) in the filtered array and use $set to append a value ("objEvents") to that object:

methods: {
  add_events (order, index) {
    const objEvents= [ external data from an API ]      
    this.$set(this.orders[index], "events", objEvents)          
  }
}

However the index of the component in the filtered array ("filtered") is not the same as its index in the original array ("orders") and so the add_events method targets the wrong component.

Can I use key to target the correct component? or is there some other way to identify the target component in the filtered array?

Answer 1

There's no need to track index. filtered is just an array of references to the original objects in orders, so you could modify the order iterator in add_events() to achieve the desired effect:

this.$set(order, 'events', objEvents);

new Vue({
  el: '#app',
  data() {
    return {
      orders: [
        {id: 1, order_number: 111, name: 'John', reference: 'R111'},
        {id: 2, order_number: 222, name: 'Bob', reference: 'R222'},
        {id: 3, order_number: 333, name: 'Bob', reference: 'R333'},
      ],
      search: ''
    };
  },
  computed: {
    filtered() {
      return this.orders.filter(order => {
        const s =
              order.order_number + order.reference + order.name;
        const su = s.toUpperCase();
        return su.match(this.search.toUpperCase());
      });
    }
  },
  methods: {
    add_events(order, index) {
      const objEvents = [
        {id: 1, name: 'Event 1'},
        {id: 2, name: 'Event 2'},
        {id: 3, name: 'Event 3'}
      ];
      this.$set(order, "events", objEvents);
    }
  }
})

<script src="https://unpkg.com/vue@2.5.17"></script>

<div id="app">
  <input type="text" v-model="search" placeholder="Search">
  <table>
    <tbody v-for="(order, index) in filtered" :key="order.id">              
      <tr>
        <td @click="add_events(order, index)">{{order.order_number}}</td>
        <td>{{order.reference}}</td>
        <td>{{order.name}}</td>
        <td>{{order.events}}</td>
      </tr>
    </tbody>
  </table>
  
  <pre>{{orders}}</pre>
</div>

Answer 2

You could map the original array and add the an origIndex property to each item as follows :

    computed:{
        filtered(){
           let mapped= this.orders.map((item,i)=>{
                             let tmp=item;
                              tmp.origIndex=i;
                             return tmp;
                            });
             return this.mapped.filter(order => {
                    const s =
                      order.order_number + order.reference + order.name;
                       const su = s.toUpperCase();
                    return su.match(this.search.toUpperCase());
             });
            }
        }//end computed

In your template use the origIndex property instead of index

           <tbody v-for="(order, index) in filtered" :key="order.id">              
              <tr>       
                <td @click="add_events(order, order.origIndex)>{{order.order_number}}</td>
               <td>{{order.reference}}</td>
                <td>{{order.name}}</td>
                 ...
               </tr>
            </tbody>