11.11: Events

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Each mouse movement, click and keyboard keystroke corresponds to a particular event. Mondrian offers a rich hierarchy of events. The root of the hierarchy is MOEvent. To associate a particular action to an event, a handler has to be defined on the object interaction. In the following example, clicking on a class opens a code browser:

view shape rectangle
    width: [ :each | each instVarNames size * 5 ];
    height: [ :each | each methods size ];
    if: #hasAbstractMethods fillColor: Color lightRed;
    if: [:cls | cls methods anySatisfy: #isAbstract ] fillColor: Color red.

view interaction on: ROMouseClick do: [ :event | event model browse ].

view nodes: Collection withAllSubclasses.
view edgesFrom: #superclass.
view treeLayout.

The block handler accepts one argument: the event generated. The object that triggered the event is obtained by sending modelElement to the event object.