MUI Checkbox and Switch within Controller don't work as expected without default values.

Describe the bug If a default value is not provided for MUI Checkbox or Switch, the component will return empty string as value on submit.

To Reproduce

1. Go to sandbox example
2. Click on Submit

{}

1. Check the checkbox and the switch and click on Submit again.

{
  "Checkbox": "",
  "switch": ""
}

1. Uncoment defaultValues (lines 25-27).

const defaultValues = {
  TextField: "",
  Checkbox: false,
  switch: false,
};

1. repeat step 3.

{
  "Checkbox": true,
  "TextField": "",
  "switch": true
}

Codesandbox link (Required) The sandbox example is a stripped down version of example from Controlled input.

https://codesandbox.io/s/react-hook-form-controller-d76q8

Expected behavior Both MUI Checkbox and Switch should return bool values even if default values were not set.

Desktop (please complete the following information):

• OS: Chrome OS
• Browser: Chrome
• Version: 81

[bluebill1049]

we detect if this is a checkbox by the initial value.

[bluebill1049]

Would it be possible/reasonable to detect if it is a checkbox by type passed to it? I see in examples that type is passed to Controller.

no, that’s the thing: we can’t guarantee by type, some of the checkbox (non MIUI) return string…