@Override protected Composite doCreatePreviewPane(Composite composite, int numColumns) { super.doCreatePreviewPane(composite, numColumns); Composite previewLineWidthContainer= new Composite(composite, SWT.NONE); previewLineWidthContainer.setLayout(createGridLayout(2, false)); final NumberPreference previewLineWidth= new NumberPreference(previewLineWidthContainer, 2, fPreviewPreferences, LINE_SPLIT, 0, 9999, FormatterMessages.LineWrappingTabPage_line_width_for_preview_label_text); fDefaultFocusManager.add(previewLineWidth); previewLineWidth.addObserver(fUpdater); previewLineWidth.addObserver(new Observer() { @Override public void update(Observable o, Object arg) { fDialogSettings.put(PREF_PREVIEW_LINE_WIDTH, fPreviewPreferences.get(LINE_SPLIT)); } }); return composite; }