Developing a DSL Graphical Notation - Eclipse Modeling Project: A Domain-Specific Language Toolkit - page 166

4.5.4 Generation

As usual, we invoke the transformation from mapping to generator model using
the context menu Create Generator Model on our scenario.gmfmap model. In
the generator model, we change the Diagram File Extension property to
scenario , and we set the Same File For Diagram And Model property to
true , as seen in Figure 4-34.

Figure 4-34 Scenario GMF generator model

We next generate our scenario diagram plug-in and move on to making some
of the necessary code changes—or you can run the diagram now to see how it
looks.

Border Item Adjustment
Our border item Event nodes are offset by default so that the edge of the node
meets the edge of the parent. For our Event nodes, we want them to straddle the
border, so we must modify the addFixedChild() method of the parent
TaskEditPart class to set the offset to half the diameter of the Event circle fig-
ure. The modified method follows, showing the general EventXEditPart mod-
ification, where X is replaced by the number of each side-affixed event. A better
solution would be to use childEditPart.getSize().width/2 to calculate
the offset. Changes appear in bold.

/**
* Modified to add border offset for overlapping event nodes
*
* @generated NOT
*/
protected boolean addFixedChild(EditPart childEditPart) {
if (childEditPart instanceof TaskNameEditPart) {