Did Officer Friendly violate Grant’s Fourth Amendment’s rights when he searched his pants pockets,

Officer Friendly is riding through the Dardow community when he sees Grant smoking a marijuana cigarette. Officer Friendly arrests Grant for possession of marijuana. Officer Friendly searches Grant before putting him in the police car and he finds crack cocaine and a crack pipe in Grant’s back pocket. Did Officer Friendly violate Grant’s Fourth Amendment’s rights when he searched his pants pockets, i.e. was the search of Grant’s pockets an “unreasonable” search under the Fourth Amendment? Please Explain