I've tried to make a checkbox-cell in datatatable with vuetify, but it doesn't work

I'd like to make a checkbox in a datatable, where the checkbox is ticked when the user (datatable contains users) is an admin.

I tried this code, but it doesn't work. {{value==1}} works, so the value is true/false. But the checkbox doesn't change.

What can I do?

<template v-slot:item.admin="{value}">
        <v-checkbox>
                readonly
				:value="value==1"
		></v-checkbox>
	    {{value==1}}
</template>

Use v-model to set the checkbox state.

I think you may have an issue setting the v-slot for the template. Typically, item is passed to the v-slot value and then when referenced to get a key's value use item[key], e.g item.admin, assuming admin is going to be 0,1,true,false, null, or undefined.

The refactor to your provided code would be:

<template v-slot:item.admin="{item}">
  <v-checkbox>
    v-model="item.admin"
    :ripple="false"
    readonly
  ></v-checkbox>
</template>
<!-- :ripple="false" is to remove the animation on click -->

Working example:

<!-- begin snippet: js hide: false console: false babel: false -->

<!-- language: lang-js -->

Vue.config.productionTip = false;
new Vue({
  el: '#app',
  vuetify: new Vuetify(),
  data () {
    return {
      headers: [
        {
          text: 'Name',
          width: '9rem',
          value: 'name',
        },
        { 
          text: 'Is Admin',
          value: 'admin'
        }
      ],
      users: [
        {
          name: 'Person A',
          admin: 1
        },
        {
          name: 'Person B',
          admin: 0
        }
      ],
    }
  }
})

<!-- language: lang-css -->

.v-data-table {
  width: 16rem;
}

<!-- language: lang-html -->

<link href="https://fonts.googleapis.com/css?family=Roboto:100,300,400,500,700,900" rel="stylesheet"/>
<link href="https://cdn.jsdelivr.net/npm/@mdi/font@4.x/css/materialdesignicons.min.css" rel="stylesheet"/>
<link href="https://fonts.googleapis.com/css?family=Material+Icons" rel="stylesheet"/>
<link href="https://cdn.jsdelivr.net/npm/vuetify@2.1.14/dist/vuetify.min.css" rel="stylesheet"/>


<script src="https://cdn.jsdelivr.net/npm/vue@2.x/dist/vue.js"></script>
<script src="https://cdn.jsdelivr.net/npm/vuetify@2.x/dist/vuetify.js"></script>

<div id="app">
  <v-app id="inspire">
    <v-data-table
      :headers="headers"
      :items="users"
      class="elevation-1"
      hide-default-footer
    >
      <template v-slot:item.admin="{ item }">
        <v-checkbox v-model="item.admin" readonly :ripple="false"></v-checkbox>
      </template>
    </v-data-table>
  </v-app>
</div>

<!-- end snippet -->