...in Class: ActionBarContributor...
...in Method: contributeToToolBar...
toolBarManager.add(getAction(GEFActionConstants.ZOOM_IN));
toolBarManager.add(getAction(GEFActionConstants.ZOOM_OUT));
toolBarManager.add(new ZoomComboContributionItem(getPage()));
2. Connect the Zoom Manager with your edit part:
...in Class: YourEditor...
...in Method: configureGraphicalViewer...
ScalableFreeformRootEditPart rootEditPart= new ScalableFreeformRootEditPart();
getGraphicalViewer().setRootEditPart(rootEditPart);
ZoomManager manager = rootEditPart.getZoomManager();
IAction action = new ZoomInAction(manager);
getActionRegistry().registerAction(action);
action = new ZoomOutAction(manager);
getActionRegistry().registerAction(action);
//define the zoom possibilities
double[] zoomLevels = new double[] {0.25,0.5,0.75,1.0,1.5,2.0,2.5,3.0,4.0};
manager.setZoomLevels(zoomLevels);
...in Method: getAdapter...
if (type == ZoomManager.class)
return ((ScalableFreeformRootEditPart) getGraphicalViewer().
getRootEditPart()).getZoomManager();
That's all! Now you have two buttons to zoom in and zoom out. And you can see the zoom level in percent. With the example here you can change zoom level from 25% to 400%.
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