Bug 45509 Allow to disable icons in vertical ruler
I20031023 A feature for Dirk
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/JavaEditorPreferencePage.java
fContentAssistColorList.getDisplay().asyncExec(new Runnable() {
			public void run() {
				if (fContentAssistColorList != null && !fContentAssistColorList.isDisposed()) {
					fContentAssistColorList.select(0);
					handleContentAssistColorListSelection();
				}
			}
		});
	}
	
	private void initializeFields() {
		
		Iterator e= fColorButtons.keySet().iterator();
		while (e.hasNext()) {
			ColorEditor c= (ColorEditor) e.next();
			String key= (String) fColorButtons.get(c);
			RGB rgb= PreferenceConverter.getColor(fOverlayStore, key);
			c.setColorValue(rgb);
		}
		
		e= fCheckBoxes.keySet().iterator();
		while (e.hasNext()) {
			Button b= (Button) e.next();
			String key= (String) fCheckBoxes.get(b);
			b.setSelection(fOverlayStore.getBoolean(key));
		}
		
		e= fTextFields.keySet().iterator();
		while (e.hasNext()) {
			Text t= (Text) e.next();