Working with Replaceable Components

Replaceable components enable you to define what classes can be selected when replacing the component class. You can use replaceable components, for example, to build templates. Replaceable components also enable you to redeclare classes in the component.

Note: A replaceable component is indicated the following ways:

In the Component Browser by an "R" on the component icon.
In the diagram, by default, displayed as framed. This is defined by the preference Frame replaceable/redeclared components. To specify this option, select Me > Preferences > App Preferences > 3D Modeling > Systems Modeling and Execution > Dymola Behavior Modeling , the Editor tab, the Components Visualization group.

This task shows you how to:

Create a Replaceable Component
Replace the Class of a Replaceable Component
Redeclare a Class in a Replaceable Component

Create a Replaceable Component

You can create replaceable components.

Instantiate a component.
Right-click the component and select Edit Component Parameters, the Attributes tab.
In this tab, in the Properties group:
1. Activate Replaceable.
2. Optional: Activate Add selector for all matching choices.
Optional: In the same tab:
1. Activate Constraining clause
2. To select a base class as the constraining class, select it using the list.
  The default is the class of the component when instantiated.
  
  Tip: Selecting a base class is useful when you create templates.
3. To select any class, click Browse for class to browse for it.
  Note: You have a dynamic search option in the selection pane that appears to browse for the class.
4. To add modifiers to the constraining clause, enter them into the box.
  An example might be to specify a start time. This start time is then applied to all classes used to replace this component.
5. To redeclare the component, click Edit .
  A new parameter dialog appears, where you can edit the redeclaration.
Click OK to define your component as replaceable.

Tips: To create a replaceable component, you can also do any of the following:

Instantiate a partial class: the created component is automatically defined as replaceable.
From any browser containing classes, for example, the main Package Browser, drag the class you want to make replaceable in your model to the Component Browser and select Add class parameter. For more information, see Dragging a Model, Block, Type, or Record to the Component Browser.

Replace the Class of a Replaceable Component

You can replace the class of a top-level replaceable component. What classes you can replace with depends on how the replaceable component is defined.

Before you begin:

Open a model that you can edit and that contain replaceable components.
Open the libraries that contain classes you want to be able to use to replace the classes of replaceable components.

Right-click a replaceable component and select Change Class > Matching Choices .
Tip: You can also perform this command from the Component Browser.
Notes:
- You can only replace the class of one component at a time, multiselecting a number of components and applying the command only works on the first selected component.
- You can select to exchange the class without considering it being replaceable. See Exchanging a Component Class.
  Note: This is for advanced users since it is not following the idea of making the component replaceable in the first place.
The Matching Choices dialog box appears.
In the dialog box, click the class you want to use.
The class of the selected component is replaced by the selected class.
Note: If you have replaced a joint of another type with a cut joint this way, you must also recompute the cut joint configuration. See Recomputing the Cut Joint Configuration.

Redeclare a Class in a Replaceable Component

When a component is replaceable, you can redeclare one or several of its classes.

In a replaceable component, you can redeclare:

the class of a component when it is inherited
the class of a subcomponent.

Warning: When you redeclare a class, you must ensure compatibility with the component, taking into account the constraining clause.

From the Component Browser, right-click a replaceable component, and select Define Redeclare Attributes.
The Define Redeclare Attributes dialog box appears.
The Component Class area displays:
- the class of the component
- the redeclaring class, if the component class has already been redeclared. In such case, you can retrieve the component class by clicking Erase .
The Select which library to search in area displays the libraries linked with the current library (through an Extends link).
To display other libraries, click Search.
The Content Chooser dialog box is displayed.
Use the Content Chooser to do any of the following:
For more about the Content Chooser, see Selecting Objects Using the Content Chooser.
- Select or multiselect from the tree.
  To multiselect, you must activate Multiselection.
  Important: You cannot select from the Package Browser.
- Use the Search box of the top bar to search and then select or multiselect from the result.
  To multiselect, you must activate Multiselection.
  Tip: Enter the name of the library in the Search box and press Enter to search. The wildcard * can be used.
  For general information about search, see About 3DSearch Queries.
The selected library is added in the Define Redeclare Attributes dialog box.
From the Select which library to search in area, select a library in the list.
The Matching Classes area displays all compatible classes.
Select a matching class.
From the Properties area, define properties for this class:
- Replaceable: to keep the component replaceable. By default, this option is not selected.
- Constrained by: if you select a replaceable option, you can add a constraining clause.
Click OK to close the dialog box and validate your change.
A message informs you of the redeclaration status.
Note: You are not allowed to break connections when redeclaring the component class.
Click OK to validate your modifications.
In the diagram, the class in the component is redeclared.