Vue - Pass data from child component from axios reponse

Question

I have one parent component with 2 child components. In ChildComponent1 I use axios to get my data and list it with v-for ( Cars to rent ). Every block of data has an button which upon click, it should select that vehicle. The selected vehicles data should transfer to the ChildComponent2 which is a Booking summary card, or panel so to speak. Link:

https://codesandbox.io/s/koyjjoo1y3

I'm not sure what approach to take here. I used props to pass response data from parent to child. But I have no clue how can I pass that data from 1 child to another on button click.

Result.vue / Parent

    <section class="section__results--cars">

      <div class="col-lg-8">
         <cars-details></cars-details>
      </div>
      <div class="col-lg-4">
          <booking-summary></booking-summary>
      </div>
    </section>


CarsDetails.vue / Child1

<v-card class="mb-3" v-for="car in cars" :key="car.id">
  <img :src="car.image"></img>
     <h4 class="title">{{ car.title }}</h4>

        <car-attributes
           :maxPersons="car.maxPersons"
           :maxLuggage="car.maxLuggage"
           :interiorColor="car.interiorColor"
           :exteriorColor="car.exteriorColor"
        ></car-attributes>

        <div>
          <span class="price__title">Hourly price</span>
          <span class="price__value">{{ car.pricePerHour }}€</span>
          <v-btn @click="passData">Select Car</v-btn>
        </div>
        <div>
          <h6 class="subheading font-weight-medium">Description</h6>
          <p>{{ car.description }}</p>
        </div>
</v-card>
<script>
    import axios from "axios";
    const URL = "https://next.json-generator.com/api/json/get/NJgWweNm8";
    import CarAttributes from "@/components/cars/CarAttributes";
    export default {
      name: "carsdetails",
      components: { CarAttributes },
      data: () => ({
        cars: []
      }),
      mounted() {
        axios
          .get(URL)
          .then(response => {
            this.cars = response.data;
          })
          .catch(e => {
            this.errors.push(e);
          });
      }
    };
    </script>



BookingSummary.vue / Child2

<v-card>
   <h4>Booking Summary</h4>
   <h6>{{ car.title }}</h6>
   <h6>{{ car.maxPersons}}</h6>
</v-card>

Answer 1

The main design pattern is Data -> Down and Events <- Up. Use $emit('some-event', payload) to push the event up the chain, and use `@some-event="yourFunction" to handle it.

Here is an article that explains why this pattern works (and works long term): https://jasonformat.com/props-down-events-up/

For your use case

Parent

    <template>
      <div>
         <cars-details 
           v-for="(car, i) in cars" 
           :key="i" 
           :car="car" 
           @getCar="getCar" 
         />
      </div>
      <div v-if="selectedCar">
          <booking-summary :car="selectedCar" />
      </div>
    </template>

    <script>
      export default {
        data: {
          cars: [car1, car2, ...],
          selectedCar: null
        },
        methods: {
          getCar(car) {
            this.selectedCar = car
            // Do axios call for the `car` object
          }
        }
      }
    </script>


Child1

    <template>
      ...
      <div>
        ...
        <v-btn @click="passData">Select Car</v-btn>
      </div>
    </template>

    <script>
      export default {
        ...
        props: {
          car: { required: true }
        },
        methods: {
          passData() {
            this.$emit('getCar', this.car)
          }
        }
      }
    </script>


Child2

    <template>
      ...
    </template>

    <script>
      export default {
        ...
        props: {
          car: { required: true }
        },
      }
    </script>