I am using PlaceAutocompleteFragment to search places. Below is my xml code
This question is a bit old, but I'll leave this here for future viewers.
While @rajat44's answer solves it when you have one PlaceAutocompleteFragment, if you have multiple you can do this:
pacf.getView().findViewById(R.id.place_autocomplete_search_button).setVisibility(View.GONE);
pacf2.getView().findViewById(R.id.place_autocomplete_search_button).setVisibility(View.GONE);