Brake pedal wont hold when applied

my friend honda civic has a brake problem it start when he overheat the brake shoes coz he forgot to remove the e-brake 7 miles..so he come to me and i checked and its has a burn brakes shoes and also leaking wheel cylinder so i suggest that he need to change his brake shoes also his wheel cylinder coz when he applying the brakes pedal its leaking big time so i also change it my also he said he change the brake pad for some reason i dont know but my question is after changing all of this he still having a problem with his brake it wont hold when he apply the brake pedal it grab in the beggining but its drooping until hit to the floor also when that happen the engine stall..any help will appreciate thank you GOD bless..