Very happy, City, with figure in charge (8)
I believe the answer is:
ecstatic
'very happy' is the definition.
'city with figure in charge' is the wordplay.
'city' becomes 'ec' (the City of London postcode).
'with' means one lot of letters go next to another.
'figure' becomes 'stat' (I've seen this before).
'in charge' becomes 'ic' (abbreviation for 'in charge').
'ec'+'stat'+'ic'='ECSTATIC'
(Other definitions for ecstatic that I've seen before include "Transported by joy" , "Joyful" , "In a state of great delight" , "Euphoric" , "Full of bliss" .)