Named Groups

Named Groups provide a way for a MicroStation user to connect logically a set of MicroStation graphic elements. Named groups can include elements from the active file and those from directly attached references. Elements in a named group can be manipulated collectively: read MicroStation help for more information. The MicroStation user interface makes it easy to create a named group and add and remove elements in that group …

Enumerate Named Groups Using Python

Get the named groups collection for a specified DGN model like this …

dgn_model: DgnModel = ISessionMgr.ActiveDgnModelRef
named_groups = NamedGroupCollection(dgn_model)

Function list_named_groups()

Here's a function that uses that call and then enumerates the NamedGroup objects in that collection …

from MSPyBentley import *
from MSPyBentleyGeom import *
from MSPyDgnPlatform import *
from MSPyDgnView import *
from MSPyMstnPlatform import *

from  NamedGroups.common import  (VersionInfo, collect_named_groups, named_group_collection_to_dictionary, named_group_collection_to_list, )
from  NamedGroups.named_group_proxy import  NamedGroupProxy

def list_named_groups(dgn_model: DgnModel = ISessionMgr.ActiveDgnModelRef)->int:
    """
    List the Named Groups found in a DGN model.

    Returns: The number of Named Groups found.
    """
    n_groups = 0
    assert dgn_model is not None, "No DGN model reference supplied"

    # Create a NamedGroupCollection for the specified model
    n_groups, named_group_collection = collect_named_groups(dgn_model)
    if 0 == n_groups:
        msg = "No Named Groups found in the DGN model"
        MessageCenter.ShowErrorMessage(msg, msg, False)
        return 0

    msg = f"{n_groups} Named Groups in the DGN model:"
    MessageCenter.ShowInfoMessage(msg, msg, False)
    group_list = named_group_collection_to_list(named_group_collection)

    print("Enumerate group_list...")
    for i, proxy in enumerate (group_list):
        msg = f"[{i}] {proxy}"
        print(msg)
        MessageCenter.ShowInfoMessage(msg, msg, False)

	#  Convert the list to a dictionary, for no particular reason
	#  (We perform this conversion in the write-to-JSON module)
    print("Enumerate groups_dict...")
    groups_dict = named_group_collection_to_dictionary(named_group_collection)
    for i, proxy in enumerate (groups_dict.values()):
        msg = f"[{i}] {proxy}"
        MessageCenter.ShowInfoMessage(msg, msg, False)

    return n_groups

Function collect_named_groups()

def collect_named_groups(dgn_model: DgnModel = ISessionMgr.ActiveDgnModelRef)->(int, NamedGroupCollection):
    """
    Create a list of Named Groups found in a DGN model.
    Each Named Group is collected as a dictionary of tuples,
    each containing  ('Name': name, 'Value': value, 'Type': ng_type)

    Returns: tuple (int, NamedGroupCollection collection of Named Groups).  NamedGroupCollection is not a Python list.
    """
    assert dgn_model is not None, "No DGN model reference supplied"

    # Create a NamedGroupCollection for the specified model
    named_group_collection = NamedGroupCollection(dgn_model)
    n_groups = len(list(named_group_collection))
    print(f"{n_groups} Named Groups in the DGN model...")
    for i, group in enumerate (named_group_collection):
        assert group is not None
        proxy = NamedGroupProxy(group, dgn_model)
        print(f"[{i}] {proxy}")

    if 0 == n_groups:
        print("No Named Groups found in the DGN model")

    return (n_groups, named_group_collection)

Function named_group_collection_to_list()

def named_group_collection_to_list(named_group_collection: NamedGroupCollection)->(int, list[NamedGroupProxy]):
    '''
    Convert a NamedGroupCollection to a Python list.

    Returns: tuple (int, list[NamedGroupProxy])
    '''
    print("named_group_collection_to_list...")
    n_groups = 0
    dgn_model = named_group_collection.GetModelRef().GetDgnModel()
    ng_list = []

    for i, group in enumerate (named_group_collection):
        proxy = NamedGroupProxy(group, dgn_model)
        print(f"[{i}] {proxy}")
        ng_list.append(proxy)
    n_groups = len(ng_list)
    print(f"named_group_collection_to_list {len(ng_list)} groups")
    return n_groups, ng_list

__main__ function

if __name__ == "__main__":
    vinfo = VersionInfo("List Named Groups", 26, 2, 23, "Show Named Groups in a DGN file")
    MessageCenter.ShowInfoMessage(vinfo.brief, vinfo.verbose, False)
    list_named_groups()

Class VersionInfo

VersionInfo is a small class I use to store version information. Read more here.

Class Python-NamedGroupProxy

Python-NamedGroupProxy is a small class I use to help with Named Group programming. Class NamedGroupProxy is explained here.

Questions

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