Qt, how does Synchronize move two windows?

recently writing a player, now there are two window classes, one is QMainWindow class: SImplePlayer, is my video window; the other is playlist, QDialog class, I want to drag the video window, that is, my SimplePlayer window, my playlist can move, what should I do?

move the window on the left and move the window on the right. What should I do?

Qt
Dec.12,2021
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