How to watch directions of pagination in v-data-table vuetify

Question

I need make different get requests to backend depending on whether I move forward or backward on the table. What event I must use and how to make this?

Answer 1

You could use @pagination event from data-table. It emits an object like this:

{page: 2, itemsPerPage: 5, pageStart: 5, pageStop: 10, pageCount: 2}

So you can capture it in a custom method and determine if 'page' value is higher or lower than current value in order to know if is forward or backward. An example:

<template>
<div>
  <v-data-table
    :headers="headers"
    :items="desserts"
    :items-per-page="5"
    class="elevation-1"
    @pagination="writeLog"
  ></v-data-table>
</div>
</template>
<script>
  export default {
    data () {
      return {
        headers: [
          {
            text: 'Dessert (100g serving)',
            align: 'start',
            sortable: false,
            value: 'name',
          },
          { text: 'Calories', value: 'calories' },
          { text: 'Fat (g)', value: 'fat' },
          { text: 'Carbs (g)', value: 'carbs' },
          { text: 'Protein (g)', value: 'protein' },
          { text: 'Iron (%)', value: 'iron' },
        ],
        desserts: [
          {
            name: 'Frozen Yogurt',
            calories: 159,
            fat: 6.0,
            carbs: 24,
            protein: 4.0,
            iron: '1%',
          },
          {
            name: 'Ice cream sandwich',
            calories: 237,
            fat: 9.0,
            carbs: 37,
            protein: 4.3,
            iron: '1%',
          },
          {
            name: 'Eclair',
            calories: 262,
            fat: 16.0,
            carbs: 23,
            protein: 6.0,
            iron: '7%',
          },
          {
            name: 'Cupcake',
            calories: 305,
            fat: 3.7,
            carbs: 67,
            protein: 4.3,
            iron: '8%',
          },
          {
            name: 'Gingerbread',
            calories: 356,
            fat: 16.0,
            carbs: 49,
            protein: 3.9,
            iron: '16%',
          },
          {
            name: 'Jelly bean',
            calories: 375,
            fat: 0.0,
            carbs: 94,
            protein: 0.0,
            iron: '0%',
          },
          {
            name: 'Lollipop',
            calories: 392,
            fat: 0.2,
            carbs: 98,
            protein: 0,
            iron: '2%',
          },
          {
            name: 'Honeycomb',
            calories: 408,
            fat: 3.2,
            carbs: 87,
            protein: 6.5,
            iron: '45%',
          },
          {
            name: 'Donut',
            calories: 452,
            fat: 25.0,
            carbs: 51,
            protein: 4.9,
            iron: '22%',
          },
          {
            name: 'KitKat',
            calories: 518,
            fat: 26.0,
            carbs: 65,
            protein: 7,
            iron: '6%',
          },
        ],
      }
      currentPage = 1
    },
    methods: {
       writeLog(paginationObject){
            let action
            console.log(paginationObject);
            this.currentPage < paginationObject.page ? action = 'forward' : action ='backguard'
            this.currentPage = paginationObject.page
            console.log(action)
            //Write code to call your backend using action...
        }
    },

  }
</script>