Confident attitude about current ITV broadcast (8)
I believe the answer is:
positive
'confident' is the definition.
('positive' can be similar in meaning to 'confident')
'attitude about current itv broadcast' is the wordplay.
'attitude' becomes 'pose' (I've seen this before).
'about' is an insertion indicator.
'current' becomes 'i' (symbol for electric current).
'broadcast' indicates an anagram.
'i'+'itv'='iitv'
'iitv' with letters rearranged gives 'itiv'.
'pose' enclosing 'itiv' is 'POSITIVE'.
(Other definitions for positive that I've seen before include "'Definite, categorical (8)'" , "Confident, very sure" , "Definite, confident" , "Definite, sure" , "Certain, confident in opinion" .)