I don't get what the problem is with learning the notes, why you'd want an easy way when there's not really a hard way.
Learn the notes on each string from the 1st fret to the 4th, including the open strings that's just 20 notes on a 4 string bass, and they're pretty much just the alphabet from E onwards (ok so you've a few #'s, but it's really not exactly particle physics). The note at the 5th fret is the same as the open next higher string, the notes from the 5th fret onwards are the same as the next higher strings from the 1st fret, and this keeps repeating onwards and upwards. So from the 10th fret you're talking the 2nd highest string etc.
E string - F, F#,G, G#
A string - A#, B, C, C#
D string - D#, E, F, F#
G string - G#, A, A#, B
If you look at the above you'll see that descending across the neck (moving down from the G string), the notes move in the cycle of 5ths e.g. start on A, the next note is its 5th E, the next is its 5th B etc.
If you look ascending it's the cycle of 4ths e.g. start on F and the neighbouring note on the next string is A# (same note as Bb) etc.