7. EQUITY COMPENSATION PLANS (Details - Share based compensation) - USD ($)	3 Months Ended		9 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2018	Jan. 31, 2017
Share based compensation	$ 412,000	$ 869,000	$ 1,206,000	$ 2,591,000
Cost of contract manufacturing [Member]
Share based compensation	139,000	23,000	277,000	89,000
Selling, general and administrative [Member]
Share based compensation	259,000	389,000	589,000	1,183,000
Discontinued Operations [Member]
Share based compensation	14,000	457,000	340,000	1,319,000
Stock Options [Member]
Share based compensation	374,000	815,000	1,070,000	2,369,000
ESPP [Member]
Share based compensation	$ 38,000	$ 54,000	$ 136,000	$ 222,000