Green’s Dictionary of Slang

(Aus./US black) on bad = good pattern, first-rate, attractive.

1907		C.W. Chandler Darkest Adelaide 8/1: Th’ cobber ’ad arsked ’is (th’ bloke’s) belle [...] to ’ave a drop o’ tiddley so ’e (th’ bloke) ’ad invited ’is (th’ cobber’s) tricky little kid to ’ave a drop o’ lush, too.
1936		A.E. Duckett ‘Truckin ’round Brooklyn’ in N.Y. Age 18 Jan. 7/1: Brooklyn at last has a really pretty ballroom...the Bedford Palace... [...] the setup is very tricky, indeed.
1937		Duckett & Staple ‘Double Feature’ in N.Y. Age 15 May. 7/2: He walked in with another tricky miss.