Change estimate shipping country programatically

Question

I want to change the country in estimate shipping (cart page) programatically in my module (meaning user clicks on a button in footer on homepage and I change the shipping country on cart page for that session):

However it doesn't work if I do it with the session object.

// Magento\Checkout\Model\Session;

$quote = $this->session->getQuote()
$quote->getShippingAddress()->setCountryId('GB')->save();
$quote->getShippingAddress()->getCountryId() // returns GB which is right, but the sidebar on frontend is still showing US on refresh. 

Answer 1

This needs to be done with js. Something like:

var countryData = customerData.get('checkout-data');
            if (countryData()) {
                if (countryData().shippingAddressFromData) {
                    countryData().shippingAddressFromData.country_id = "GB";
                } else {
                    countryData().shippingAddressFromData = {};
                    countryData().shippingAddressFromData.country_id = "US;
                }
                customerData.set('checkout-data', countryData());
            }

Answer 2

This should be $quote->setShippingAddress()->getCountryId()->save();

Answer 3

use this: $quote->getShippingAddress()->setCountryId("GB")->save()