ios - Show wrong route direction Alert in google maps for Xcode -

i doing maps related app, in app drawing route line location location, based on root line user reach destination.but issue need display alert whenever user take wrong direction.

i have 1 suggestion if work u or not go through once.

you check current location in source , destination path eg.. current location latitude , latitude values should check source , destination values.if current location out of range can display alert message.