title: Customizing schema fields in sanity.io
body: <p>In sanity studio schema I made some object type with one field, dependent of other. If "all" field check to true, then "date" field should be hidden or disabled. </p>
  
  <p>But I don't know how to realize it. I tried to find examples, or guides in docs, but found nothing. 
  I will be grateful for the help and advice.</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>const dateTime = {
    name: 'dateTime',
    type: 'object',
    fields: [
      {
        name: 'all',
        type: 'boolean',
      },
      {
        name: 'date',
        type: 'date',
      },
    ],
  };</code></pre>
  </div>
  </div>
  </p>