private void setSourceButtonState(final int ss) {
        sources.setCheckedButtonByIndex(0, isAttributeFilterSourcesGC(ss));
        sources.setCheckedButtonByIndex(1, isAttributeFilterSourcesOkapi(ss));
    }
helper to set the correct button states, can't use sourcesState as that gets changed by setting the button states
main/src/main/java/cgeo/geocaching/filters/gui/AttributesFilterViewHolder.java