public void setSelectionModel(SelectionModel<? super T> selectionModel,
                                  CellPreviewEvent.Handler<T> selectionEventManager) {
        // Remove the old manager.
        if (this.selectionManagerReg != null) {
            this.selectionManagerReg.removeHandler();
            this.selectionManagerReg = null;
        }

        // Add the new manager.
        if (selectionEventManager != null) {
            this.selectionManagerReg = addCellPreviewHandler(selectionEventManager);
        }

        // Set the selection model.
        setSelectionModel(selectionModel);
    }
Set the {@link SelectionModel} that defines which items are selected and
the {@link com.google.gwt.view.client.CellPreviewEvent.Handler} that
controls how user selection is handled.

@param selectionModel the {@link SelectionModel} that defines selection
@param selectionEventManager the handler that controls user selection
stroom-core-client-widget/src/main/java/com/google/gwt/user/cellview/client/AbstractHasData.java