我不做大哥好多年

Thank you for your reply. I think the original intention of ChildenExpression was Func, which is to pass in the parent node information to obtain the content of the child...

I solved this problem. The DataSource cannot use expressions or functions and needs to use fixed variables, otherwise this problem will occur.  

The problem occurred again during use, which should be due to the logic malfunctioning after resetting the data source parameters. This results in the inability to refresh the tree root...

Of course, the solution is simple, which is not to use data sources 

I misplaced the first image. 

When dragging, the crosshair of the mouse is easily reproduced when facing the title. When dragging, users usually drag onto the title. I guess the problem is that the title...

I understand what you mean and have tried it before. This is not consistent with the effect I want to achieve. I want to implement a hover trigger event on...