win32gui.DragDetect

DragDetect(hwnd, point)

captures the mouse and tracks its movement until the user releases the left button, presses the ESC key, or moves the mouse outside the drag rectangle around the specified point.

Parameters

hwnd : int

Handle to the Window

point : (int, int)

Initial position of the mouse, in screen coordinates. The function determines the coordinates of the drag rectangle by using this point.

Return Value

If the user moved the mouse outside of the drag rectangle while holding down the left button , the return value is nonzero.
If the user did not move the mouse outside of the drag rectangle while holding down the left button , the return value is zero.