Diagram templates are always associated with schematic feature classes. For the Standard builder, these schematic feature classes are related to the GIS feature classes with which the builder is supposed to deal.
When generating a diagram based on the Standard builder from a set of GIS features organized into a geometric network or a network dataset, the builder populates the schematic feature classes—that is, it creates the schematic features expected in the diagram as follows:
- It analyzes the geometric network features currently highlighted in the map document after a selection or tracing operation, or the network elements currently selected in the map document.
- For each feature layer containing these network features, it verifies whether it is expected to deal with them—that is, it verifies that a schematic feature class associated with the related GIS feature class exists for the diagram template.
If there is such a schematic feature class for the diagram template, for each feature currently highlighted in the feature layer, it creates the associated schematic feature in memory, evaluates its attributes, and initializes its topology and geometry.
- If schematic rules are specified for the related diagram template, they are executed on all the schematic features built in memory.
- If there is a default schematic layout algorithm configured for the diagram template, the algorithm is executed and the geometry for all the in-memory schematic features is updated accordingly.
- All the schematic features in memory are saved in the schematic feature classes in the schematic dataset.
- All the created schematic features are queried from the schematic feature classes, and the diagram is displayed.
Then, at any time and for its lifetime—that is, until it is deleted from the schematic dataset—the diagram can be
- Edited, laid out, and saved.
- Updated so its content stays in accord with the network features, and changes that impacted the associated GIS features are reported on the associated schematic feature. For diagrams based on GIS versioned data, it can also be updated from any other reference version; this means that even if diagram generation was based on a specific version, if this GIS data version no longer exists or is not the reference version anymore, the diagram reference version can also be changed so the diagram content evolves with the change of GIS reference version.