Activity Parameter Nodes are object nodes at the beginning and end of the flows that are used to accept inputs and provide outputs from activities.

Example of Activity Parameter Nodes in Activity diagram
 

The following steps show you how to work with Activity Parameter Nodes:

Creating an Activity Parameter Node

To create an Activity Parameter Node


  1. In the Activity diagram palette, click the arrow next to the Object Node button to expand the list, then select Activity Parameter Node.
  2. Click the Activity diagram frame. The Activity Parameter Node is created, and its shortcut menu opens.
  3. Select Edit New Parameter to specify the parameter. The Parameter dialog opens.
  4. Specify the parameter, and click Close.

The parameter for the Activity Parameter Node is created automatically.
The parameter name, type, and multiplicity are synchronized with the pin or Object Node from which/to which the Object Flow was created. The direction of the parameter is set according to the Object Flow direction, otherwise you can set it manually by simply right-clicking the activity parameter, and selecting the preferred direction.

When creating an Activity Parameter Node on a diagram frame, click on the diagram frame to open the menu. In the menu, the following Activity Parameter Nodes are listed: 

    • parameters that are not displayed on the diagram frame.  
    • parameters that are owned by the same activity as the activity diagram. 
    • parameters that have assigned parameters that are also owned by the same activity.

 

If a parameter with an inout direction is selected for the Activity Parameter Node creation, then two Activity Parameter Nodes are created on the diagram frame.

You can also create an Activity Parameter Node by drawing an Object Flow directly to or from the Activity diagram frame.

 

Setting the direction of an Activity Parameter Node

To set the direction of an Activity Parameter Node


  1. Right-click the Activity Parameter Node on the diagram, and select Specification.
  2. In the Parameter property group, click to expand the Direction options drop-down menu.
  3. Select the preferred direction, and click Close.

Displaying Activity Parameter Nodes

You can display Activity Parameter Nodes on the frame of the Activity diagram when you are:

 

To display an Activity Parameter Nodes when creating a new Activity diagram


  1. When creating a new Activity diagram for an Activity element that contains Activity Parameter Nodes, the Select Parameters dialog will open automatically.
    Automatically opened the Select Parameters dialog when creating a new Cool Room Activity diagram
  2. In the opened Select Parameters dialog, select the parameters that you want to display, and click OK.
    Selected Activity Parameter Nodes are displayed on the frame of the Activity diagram.
    Displayed Activity Parameter Nodes on the frame of the Cool Room Activity diagram

    If you want all Activity Parameter Nodes to be displayed automatically when creating a new Activity diagram, go to Options > Project on the main menu, and set the Display All Activity Parameter Nodes in Diagrams option to true.


 

To display Activity Parameter Nodes on the frame in the pre-existing Activity diagram


  1. Select the Activity diagram pane.
  2. Open the Select Parameters dialog by performing one of the following steps:
     - From the shortcut menu, select Display > Display Parameter Nodes.
     - On the diagram toolbar, click Display and select Display Parameter Nodes.

    The Display Parameter Nodes command in the Collect Computer Activity diagram
  3. In the dialog, select the parameters that you want to display, and click OK.
    The Select Parameters dialog of the Collect Computer Activity diagram
    The selected Activity Parameter Nodes are displayed on the frame of the Activity diagram.
    Displayed Activity Parameter Nodes on the frame of the Collect Computer Activity diagram

Displaying or hiding the direction of an Activity Parameter Node

To display or hide the direction of an Activity Parameter Node


  1. Right-click the Activity Parameter Node on the diagram, and select Symbol Properties.
  2. In the Symbol Properties dialog, click to select or clear the Show Direction check box to display or hide the direction.
  3. Click Close.

Example of the parameter direction displayed on Activity Parameter Node
 

  • You can see the direction of the parameter displayed in the Containment tree before choosing the parameter name.
  • If an Activity Parameter Node is associated with the parameter of  an inout direction, then the direction to the Activity Parameter Node is set according to the connected flows. If an outgoing flow is connected to the newly created Activity Parameter Node, then this Activity Parameter Node is set as an input node, and the 'in' parameter direction is used.




The model used in the figures of this page is the Activity diagram sample model that comes with MagicDraw. To open this sample do one of the following:

  • Download activity diagram.mdzip.
  • Find in modeling tool <modeling tool installation directory>\samples\diagrams\activity diagram.mdzip.