Yes.In this case, I think it may help to be American - the better to hear (understand) his accent in exactly what he's saying. I agree with Minkahed and in this case, Doc: "there ain't no end to this song...!" (I've never heard it otherwise in decades of listening..)
But on the prior point, as a huge blues fan (and also someone who has heard that Bobbie Gentry song his whole life) I never once heard (or thought) of a connection between it and "All I Needed Was the Rain," not that it's not an interesting hypothesis.
Yet I have always heard it more as a rootsy return to the blues he was steeped as a youth in Memphis. That's much more obvious, as the blues boom (the Rolling Stones and many other bands) were so influenced by it.
Structurally, I don't hear much in common, although there is a surface level similarity in instrumentality and his tone , having the quietly confessional feel of many a folk or blues song.
On the other hand, I will grant that the "acoustic" / folksy song had been millling around since the popular ascendency of Bob Dylan (and roots-based rockers like the Rolling Stones) as well as things like the Newport Jazz Festival (featuring many "rusty figs" bearing their souls on vocal and a guitar) so much that Elvis (or his writers or producers ) surely been both picking up on the same strands i(direct and indirect) in the culture.
Elvis
knew this music and this song (and others at the time) were a way of saying, "hey, I was rootsy when y'all were in diapers..."
The chronology, if true, as was pointed out, doesn't appear to bear out a direct connection between this song and the Gentry hit.