Integrating a personnalized user-interface in a CORMAS model

2. Construct a graphic interface that displaysa histogramUtilization of ‘Canvas Builder’ of VisualWorks

1. Prepare the data to be visualizedExample: structure in classes of annual age of the population of blue cephalophes in the Djemiong model

3. Connect the graphic interface to the dataBonus: activate it with a click on the spatial grid

1. Prepare the data to be visualized

In the Djemiong model, the class Duiker is characterizedby an attribute age, expressed in weeks.

Initially, the age is attributed by chance between 0 and 80.

At each time step, by the activation of the methodgrowth, each instance of Duiker sees the value of itsattribute age augmented by 1.

At each time step, by the activation of the methodmortality, each instance of Duiker is subjected to a probability to die. This probability is high for the youngsters, mild for the adults, and becomes very high when the age corresponding to the life expectancy (7 years) is reached.

The objective is to calculate the proportions of each 7 annual age group (the last being the class 7+ )

1. (continued) Write the methodDjemiong>>duikersYearlyClasses

At the level of the Cormas model Djemiong, the collection of instances of Duiker are called theDuikers.

duikersYearlyClasses| nbYearClasses yearlyClasses yearClass | nbYearClasses := 7. yearlyClasses := Array new: nbYearClasses withAll: 0. self theDuikers do: [:aDuiker | yearClass := nbYearClasses min: (aDuiker age quo: 52) + 1. yearlyClasses at: yearClass put: (yearlyClasses at: yearClass) + 1]. yearlyClasses := yearlyClasses collect: [:anInteger | (anInteger / self theDuikers size) asFloat]. ^yearlyClasses

2. Construct a graphic interfacethat displays a histogram

Open the ‘canvas builder’ from VisualWorks

2.1 Give a title to the window

2.2 Place an element of type ‘Chart’on the canvas

« Drag & drop »

2.3 Comple the properties of the element ‘Chart’

2.4 Create (‘install’) the class from the interface

Click on the icon ‘install’

Open the assistant for the creation

Complete the fields

2.4 (continued)

2.4 (end)

Name the resource

Validate

3. Link with the model Djemiong

3.1 Add an attribute cormasModelto the class Interfaces

Do not forget the accessor methods !!!

3.2 Write the method linking to the data

1. Create a new protocol ‘data’

2. Write the method that establishes the link with the data

3.3 Activate the link with a simple click