Link with Spot to Spot

when i connect a link fromSpot to toSpot,curve prop not work

When a fromSpot is a specific Spot or a “…Side” Spot, the link’s route will start with an end segment (points 0 and 1) so that it extends out from the fromPort.

The same goes for toSpot and the last segment of the route (points 2 and 3) at the toPort.

A Bezier curve has two end points (0 and 3) and two control points (1 and 2). But because you specified Spots, the end segments determine the position of the control points. Don’t set or bind the fromSpot or toSpot if you want the natural curve.

I use spot to solve a problem. When dragging a node, the connection point will change. Can it be fixed?

Please describe your problem in more detail with small screenshots. What behavior do you want as nodes move?