The onQueryTextSubmit in SearchView is processed twice in Android Java
It generates two outputs when entered from the keyboard on the emulator but it creates single output when clicked on the search button on the keypad of the emulator. So, I think you should not worry about this. On all mobile phones or tablets, this error might not going to happen.
But, searchView.clearFocus(); also works here.
You can use the following code to prevent onQueryTextSubmit
from getting executed twice:
searchView.clearFocus();