changing input connection

    I am writing a new node, but I am having two problems:
    1. when an input connection of a node is changed, the node remains with the currect setting, which can be reseted and reconfigurated according to the new input port during the configure(final PortObjectSpec[] inSpecs) execution. However, before that, I would like to introduce a confirmation message about this action (similar as it is done when the node has been already executed), but in this method, we can not insert any dialog frame, as we have not access to the workflow visual component. Am I rigth? or Do I need to implement this in a different way? Where can I insert such behaivour?
        2.  How can I configurate the visual appearence of an extended port?

Thank you very much,