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systemcomposer.interaction.OptFragment

Optional fragment in interaction

Since R2024a

    Description

    A OptFragment object is a container for operands in a sequence diagram that specifies the behavior of contained elements.

    An Opt Fragment is used to represent an IF condition in the interaction. An optional fragment has a single operand which contains the message events or other fragments that are expected when the guard condition is satisfied.

    An optional fragment is drawn as a box in the sequence diagram, with the label Opt in the box header. The operand is then drawn within this box as a separate section.

    Creation

    Access Fragment objects via the RootFragment property of the corresponding systemcomposer.interaction.Interaction object. Access the Operand property of the root fragment and then, if there are fragments within the root operand, access the Fragment property of the root operand and iterate over it to view details about each of the fragments.

    Properties

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    Operands, specified as an array of systemcomposer.interaction.Operand objects.

    Lifelines covered, specified as an array of systemcomposer.interaction.Lifeline objects.

    Parent operand, specified as an systemcomposer.interaction.Operand object.

    Universal unique identifier, specified as a character vector.

    Example: '91d5de2c-b14c-4c76-a5d6-5dd0037c52df'

    Data Types: char

    Examples

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    This example shows how to use read-only API workflows to navigate sequence diagrams in System Composer™ and display information about each of the elements.

    Open Traffic Light Example

    Open the traffic light example architecture model so that you can inspect the sequence diagrams visually and confirm the programmatic outputs.

    model = systemcomposer.openModel("TLExample");

    On the System Composer toolstrip, navigate to Modeling > Sequence Diagram to view the sequence diagrams associated with the model.

    The press detection sequence diagram in the views gallery of the top model.

    Programmatically Navigate Sequence Diagram

    Collect the sequence diagrams represented by interactions that contain specific interactions of elements in the model.

    interactions = model.getInteractions;

    For the first interaction, extract the name of the sequence diagram.

    disp("The first sequence diagram is called " + interactions(1).Name + ".")
    The first sequence diagram is called SignalSequence.
    

    For this sequence diagram, display each lifeline and the component the lifeline represents.

    for i = 1:length(interactions(1).Lifelines)
        disp("The " + interactions(1).Lifelines(i).Name + ...
        " lifeline represents the " + ...
        interactions(1).Lifelines(i).RelatedElements.Name + ...
        " component.")
    end
    The ped lamp lifeline represents the ped lamp component.
    The lampController lifeline represents the lampController component.
    The poller lifeline represents the poller component.
    The source lifeline represents the source component.
    

    Now, display the contents of one message in the root fragment.

    disp("The sequence diagram message starting at the " + ...
        interactions(1).RootFragment.Operands.Fragments(1).Name + ...
        " message end is of type " + ...
        string(interactions(1).RootFragment.Operands.Fragments(1).Message.Type) + ...
        " and the message label is " + ...
        interactions(1).RootFragment.Operands.Fragments(1).Message.Condition + ".")
    The sequence diagram message starting at the switchout message end is of type Signal and the message label is rising(sw-1).
    

    Use Iterator Utility to Step Through Sequence Diagram

    Step through the Inhibit sequence diagram using the Iterator utility.

    interaction = model.getInteraction('Inhibit');
    interaction.open

    Inhibit sequence diagram from the top model.

    Display the annotation from the interaction.

    disp(interaction.Annotations.Content)
    When inhibit is true, it means pedestrian crossing is not controlled by a walk signal on this intersection.
    

    Use an iterator to navigate through all elements of a sequence diagram before extracting their properties.

    iterator = systemcomposer.interaction.Iterator(interaction.RootFragment);
    next = iterator.next;
    while ~isempty(next)
        disp(class(next))
        next = iterator.next;
    end
    systemcomposer.interaction.RootFragment
    systemcomposer.interaction.Operand
    systemcomposer.interaction.MessageEvent
    systemcomposer.interaction.MessageEvent
    systemcomposer.interaction.MessageEvent
    systemcomposer.interaction.MessageEvent
    systemcomposer.interaction.AltFragment
    systemcomposer.interaction.Operand
    systemcomposer.interaction.MessageEvent
    systemcomposer.interaction.MessageEvent
    systemcomposer.interaction.MessageEvent
    systemcomposer.interaction.MessageEvent
    systemcomposer.interaction.Operand
    systemcomposer.interaction.MessageEvent
    systemcomposer.interaction.MessageEvent
    

    More About

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    Version History

    Introduced in R2024a