The Decision Requirements Diagram

In the Getting Started topic we introduced the basic concepts of working with diagrams in Enterprise Architect and we explained how to create a Decision Requirements diagram (DRD), add a number of elements to the diagram and connect the elements with relationships. The DMN is a visual language and the diagram is the main way that you will work with decision models, including creating them, updating them and simulating them. It is important, however, to understand that a diagram is just a view of the underlying repository and that it is used to communicate with a given audience, and the author might deliberately elect not to display all the related elements. For example, when communicating with the business stakeholders it might be important to show the Knowledge Sources that are related to the Business Knowledge Models, and so a diagram could be created showing these relationships. When communicating with a technical audience the author might consider these to be of limited value and create another diagram not showing the Knowledge Sources. The two diagrams will share many elements, and updating properties of elements on one diagram will also mean they are updated on all other diagrams where they exist. In the next section we will look at a number of facilities for working with diagrams.

Alternative Views

Even though the diagram is the most common way to work with a set of elements the tool provides a range of other ways to view the elements in a Package or diagram. These provide great flexibility, are useful in particular circumstances and are also helpful for people who find it easier to work with other modes of presentation such as lists.

These options are available from the diagram's context (right-click) menu and also from this ribbon option:

Ribbon: Design > Diagram > Views

One of the most useful of these is the List View, which presents the diagram elements in a list and allows their properties to be visualized and edited as if in a spreadsheet. This is particularly useful for properties such as Status, Version and Author. A number of properties are displayed by default but other properties, including Tagged Values, can be selected and added by using the header context (right-click) menu.

Another unique way to visualize the elements in a diagram or Package is the Specification View. This presents as both a word processor and a spreadsheet view providing a comforting experience for those business or technical modelers who are more familiar with these types of office automation tools.

There are two other views that are useful when resources have been assigned to the elements -the Gantt and Construct views. The Gantt chart shows a useful view that can be centered around a resource or an object.

Modes and Styles

Diagrams can be viewed in a number of different modes that provide a useful ways of presenting the diagram information in various business contexts. There are three modes or styles that can be applied to a diagram.

• Hand Drawn Mode - applies an effect that the elements have been hand drawn
• Whiteboard Mode - applies the hand-drawn effect and also changes the elements fill color to white as though the diagram had been drawn on a whiteboard
• Custom Style - allows great flexibility with label positions and rotations, transparency and more to create visually compelling diagrams

Layout Ribbon

Diagrams have the most impact when they are well structured and neatly laid out, and Enterprise Architect provides a large number of tools for creating compelling and highly polished diagrams that will be perfect for presentations to executive level, business and technical stakeholders alike. We have already looked at diagram themes, modes and styles, and now we will look at how to change the appearance of elements on the diagram.

Many stakeholders prefer images in diagrams, and adding some image content can make the diagram more compelling and approachable for those stakeholders. An example of the use of an image would be to replace the Knowledge Source element with an image representing the organization or source of the authority. In this diagram we see the use of an icon representing a risk assessment; colors have been used to show the separate inputs to the high level decision, and some details such as stereotypes have been suppressed in the diagram.

In addition to diagram themes and styles, Enterprise Architect also allows styles to be set for each individual element. These Styles include fill, border and font colors, and line and border thickness. These settings and others are available from the style panel of the Layout ribbon and the element icons on the right hand side of a diagram object.

There is also a useful set of alignment tools that can be applied to a selected group of elements to set uniform heights and widths, align edges and centers horizontally and vertically, and more.

Exporting

The model content in Enterprise Architect, including diagrams, can be shared with other users and tools, allowing the model content to be visualized in other contexts. Diagrams can be simply copied to the clipboard and then pasted into any other application such as a slide presentation, word processor document, web page or email. This option is available from the Diagram Image panel of the Publish ribbon.

There is also a useful diagram report that can be used to export all diagrams contained in a Package, including sub-Packages. The diagram can be exported to a variety of formats, including gif, bmp, wmf and emf. Elements in the Decision Model can also be exported to a CSV file for opening in a spreadsheet application.

When high quality documentation is required Enterprise Architect can be used to generate first class publications using a number of pre-defined or custom templates. The template engine provides a large number of configuration points and allows an organization's corporate styles to be imported, including cover pages with images that will make the final document appealing to strategic and business stakeholders.    

Filters

Diagram Filters are a handy focusing device where elements in the diagram can be either hidden or represented in a faded or altered  style to raise the prominence of the remaining elements that are the focus of the diagram. The filters can be toggled and are a useful device for presentations or publications so the audience can visualize the elements that the author wants to draw their attention to. The filters can be based on a search and can be dynamically applied to any diagram with the same effect.

This diagram shows the effect of applying this filter; notice the 'effect' chosen is Fade meaning that diagram elements that are not of type Input Data will be faded in the diagram and just the Input Data elements will remain at full strength. Other effects can be chosen providing useful options for visualizing the elements depending on how the diagram is being viewed and the audience present.

For more information see the Visual Filters Help topic.

Pan and Zoom

The Pan and Zoom facility is one of the tools that can be used to navigate around a large decision diagram. Often the resolution of a diagram must be reduced to ensure it is wholly visible, but by using the Pan and Zoom window you can leave the diagram at a readable resolution and pan around to areas of interest, zooming in when necessary. Even when you are fortunate enough to be using a large monitor, you will often want to change the scale at which you are viewing the diagram and then pan around to find the section or element of interest in the diagram, zooming into that section to see a more detailed view. The Pan and Zoom window will allow you to do this for any size diagram, with options for panning and zooming that are particularly useful during workshops or focus groups organized to discuss the model with an audience who might not be familiar with the diagram.

For more information see the Pan and Zoom topic.

Themes Colors and Styles

The use of color is an important visual cue and when used carefully and consistently can make diagram more appealing and visually compelling. There is a range of tools available starting with the diagram theme that can be set at a global level but this setting can be overridden for individual diagrams. It is also possible to override the default settings for an element's appearance including: its size, font, background and line colors the font type can also be set for individual elements. Elements can also be represented by an image either as a default for every diagram where the element appears or just for a specified diagram.

Toolbox

You will recall that, when you create a new Decision diagram or open an existing one, Enterprise Architect will display the diagram in the main canvas and also display the DMN Components Toolbox page, which provides a range of items including elements, relationships (requirements) and artifacts, which can be dragged and dropped onto the diagram.

While the elements and connectors contained in the DMN Components Toolbox page are the items a modeler needs to create Decision Requirements diagrams (DRDs), any number of other elements can be included on the DRD, or any number of elements can be copied to another diagram that can be embellished. This was described in an earlier part of this Guide, where decisions were linked to other strategic elements such as goals and objectives.