how to migrate the selection provider in e4

Question

I'm migrating Eclipse views to using the e4 framework, currently we use Ecipse 4.4.1 in compability mode.

In most views I'm setting the selection provider of the site:

site.setSelectionProvider(treeViewer);

In different handlers I then use code like this to get the selection:

IWorkbenchSite site = HandlerUtil.getActiveSite(event);
ISelectionProvider selectionProvider = site.getSelectionProvider();
ISelection selection = selectionProvider.getSelection();

Some handler even use the selection provider and if it is Viewer work with it eg refersh, expand...

ISelectionProvider selectionProvider = activeSite.getSelectionProvider();
if (selectionProvider instanceof StructuredViewer) {
...
}

The wiki describes how to handle selections new in e4. https://wiki.eclipse.org/E4/EAS/Selection

What I can't find is a way to migrate using the actual selection provider?

Answer 1

In an e4 handler you use something like:

@Execute
void execute(@Named(IServiceConstants.ACTIVE_SELECTION) IStructuredSelection selection
{
  ...
}

to get the active selection.

If you want to look at the active part you can use:

@Execute
void execute(@Named(IServiceConstants.ACTIVE_PART) MPart activePart)
{
  Object object = activePart.getObject();

  // 'object' is the class you defined for the part in the Application.e4xmi
}