This Bugzilla instance is a read-only archive of historic NetBeans bug reports. To report a bug in NetBeans please follow the project's instructions for reporting issues.
if element is associated with diagram, this association can't be deleted. e.g. element-to-element association is shown as project tree node and can be removed. But element-to-diagram association is not shown in the tree (issue 79763). There only place where it is shown is 'Element Navigation' dialog, but it is also can't be removed from there.
Element's property sheet also lists its associated diagram, but the property is non-editable.
low use case not currently impacting our installed user base.
Make it an enhancement request. Reference is meant for model element to element. Diagram is not considered an element, when associating an element with a diagram, no 'Reference' object is created for the element, instead, the diagram attribute is modified to remember this association. Hence no reference is created under element node, this information is displayed in 'element navigation dialog' and element property sheet. Enhancement can be made to use custom editor for "associated diagram" property to list all associated diagrams and allow user to add or remove items.