I think I found a way that makes it so you can harvest a wheat and get seeds back in an automatic way. I discovered on accident I put a cactus next to my wheat farm and it caused the wheat to pop and the seeds to come out. basically it was look a like a this:
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When the cactus grows it cause the seed to pop. The way I do it is I keep the water on the top of cactus till I am ready to harvest, I have a central source that I block flow of and it kill all the water allowing the cactus to grow and pop it off.
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When the cactus grows it cause the seed to pop. The way I do it is I keep the water on the top of cactus till I am ready to harvest, I have a central source that I block flow of and it kill all the water allowing the cactus to grow and pop it off.