loading start never call

[Gu3]

Hi !
It's seems that's the start method of the loading bar was never called, only the finish or fail method.
I made a custom loading bar, but It's seems the same for a traditional loading bar

for example :

<template>
  <v-overlay :value="loading" class="loading-page">
    <v-progress-circular
      indeterminate
      size="64"
    ></v-progress-circular>
  </v-overlay>
</template>

<script>
  export default {
    data: () => ({
      loading: false
    }),
    methods: {
      set(){
      --- Edit : that's work ---- 
      this.loading = true
      --- Edit ---- 
        return true
      },
      start() {
        console.log('ok')
        this.loading = true
      },
      finish() {
        console.log('ko')
        this.loading = false
      }
    }
  }
</script>

"OK" was never printed, but "KO" was...
Do I miss some point ?
Thanks you !

[Gu3]

My bad, I didn't see the set method... Maybe some documentation about it would be interesting :)
Cheers.