braintree into fliutter web using JS got this error “options.selector or options.container must reference a valid DOM node”
问题 Trying to implement Braintree payment gateway into flutter web. Still no SDK for flutter web from Braintree. So trying to implement their javascript SDK. Here is my js file function payment(auth){ var button = document.querySelector('submit-button'); console.log(auth); console.log(button); braintree.dropin.create({ authorization: auth, container: 'dropin-container' }, function (createErr, instance) { console.log(createErr); console.log(instance); button.addEventListener('click', function () {