message: docs: added checked property documentation
diff: @@ -69,6 +69,8 @@ interface FieldOptions {
  validateOnValueUpdate?: boolean; // if the field should be validated when the value changes (default is true)
  bails?: boolean; // if the field validation should run all validations
  label?: string; // A friendly name to be used in `generateMessage` config instead of the field name
  + type?: string; // The input type, can be any string. Toggles specific toggle mode for `checkbox`
  + valueProp?: string; // Used the input type is `checkbox` or `radio` otherwise ignored
  }
  interface ValidationResult {
  @@ -98,6 +100,7 @@ type useField = (
  handleInput: (e: Event) => void; // updates the field meta associated with input event and syncs the field value
  handleBlur: (e: Event) => void; // updates the field meta associated with blur event
  setValidationState: (v: ValidationResult) => ValidationResult; // updates the field state
  + checked: ComputedRef<boolean> | undefined; // Present if input type is checkbox
  };
  ```
  @@ -415,3 +418,22 @@ const { setTouched } = useField('field', value => !!value);
  // mark the field as touched
  setTouched(true);
  ```
  +
  +<code-title level="4">
  +
  +`checked: ComputedRef<boolean> | undefined`
  +
  +</code-title>
  +
  +A computed property that indicates if the field should be checked or unchecked, only available if `type=checkbox` or `type=radio` in field options. Useful if you are creating [custom checkboxes](/examples/custom-checkboxes).
  +
  +```js
  +const { checked } = useField('field', ..., {
  + type: 'checkbox',
  + valueProp: 'Checkbox value'
  +});
  +
  +checked.value; // true or false
  +```
  +
  +For more information on how you might use the `checked` property, check the [custom checkboxes example](/examples/custom-checkboxes).
  