No. Nonresidents such as travelers and tourists currently on a visa in the UK, cannot file their visa application at the Schengen embassies in the United Kingdom. Instead, they should apply for a Schengen visa at the appropriate Schengen embassy in their home country.
Kung nasa UK si Juan Dela Cruz as a visitor, hindi sya pwedeng mag-apply ng visit visa sa European countries (also known as Schengen countries). Dapat syang mag-apply ng Schengen visa sa Pilipinas.