Framing Diagram Elements

You can use a rectangular frame to visually group diagram elements.

Prerequisites

The diagram is in Edit Mode and you have selected at least one diagram node.

Frames are not available in the following diagram types:

UML activity diagram (activity)
UML sequence diagram (interaction)
UML state diagram (state machine)

Context

A rectangle is available to frame diagram elements. The frames visually group diagram elements, but have no semantic meaning.

Frames can be arranged in the background or foreground. You can change the transparency and frame thickness settings. You can assign titles for frames and position them.

You can create the rectangle in one of two ways.

Drag the Frames shape from the Design>Create Diagram Contents>New from Template gallery and drop it into the diagram, then adjust it to fit. No selection is required to do this.
Select at least one node in the diagram and select Design>Model Elements>Frame. The selected diagram elements are framed by a rectangle.

Each rectangle can be

Colored (Design>Model Elements>Colorize)
Given a specific frame thickness (Properties tool window)
Given a title and the title position can be set (Properties tool window)
Set to the foreground or background (context menu)

How to proceed

To frame a diagram area, in the scroll bar of the Design>Create Diagram Contents gallery click on New from Template at the bottom and drag-and-drop the Frame form into the diagram.

A default rectangle is inserted at the desired location in the diagram.
To frame particular diagram elements, select these diagram nodes and select Design>Model Elements>Frame.

The selected diagram elements are framed with a default rectangle.
Adjust the size and position of the frame as desired.
To colorize the rectangle and the frame, select Design>Model Elements>Colorize.

The color selection dialog appears. No Color means that the gray default frame appears again with no fill. To assign a previously selected color, click on .
To set the frame thickness, enter the Frame Thickness in pixels in the Properties tab in the Properties tool window. The value must be between 1 and 100.
To display a title, enter the frame title in the Properties tool window in the Properties tab.

The frame title is displayed centered above the frame by default.
To reposition the title, select the settings for Horizontal Alignment, Title inside and Title Position from the Properties tab in the Properties tool window.

The frame title is positioned accordingly.