How did the magical magician yif exchange watermelon and banana meat?

This is just my guess and analysis: first, he sent someone to that store to buy some watermelons and bananas (it may be that the fruit varieties in a series of stores are the same in advance, and the appearance will not be too bad), then he tampered with it, and then he went to that store when he was ready. And it will bring an inconspicuous box, giving people the illusion that the box may contain gifts or other items, and no one will notice that it is filled with fruit. Then put the fruit back when people in the shop are not paying attention, or put it directly in the performance place to tell everyone that he is going to perform. On the way, when YIF changed bananas into watermelons, he patted the lady next to him and asked, "Do you feel anything?" He must have felt something when he knocked at the door, and finally let the lady next to him eat watermelon. Why? Because the evidence will be destroyed, maybe no one will ask him to change back, because he won't go, even if others don't eat, he will eat, and the psychological analysis is over.

What did you do to analyze bananas and watermelons on the spot? Banana is to pull out another watermelon pulp in advance and put it in, and then switch the bag on the spot. His hands are so fast that I don't even know how to analyze them. Then, the watermelon marked the place where the bought watermelon should be cut with a knife in advance. Watermelons have many scars on their surfaces. They may have made them themselves. Then use a prop to make a hole in the side of the watermelon, take out the prepared part of the watermelon, put the cut banana aside and the other side on the other side, which is measured (mark this part very carefully). Then take out the watermelon part (this prop is very accurate and the traces are very thin), add some soil to cover it up, and add some traces (either natural or artificial) to cover it up. Then perform, cut it for the first time according to the mark, you can pause the video and take a closer look at the melon pulp inside. Then the banana appeared for the second time, probably because he spun it and rubbed off the skin of the melon pulp. (Every move is very skilled)