Scrollbar disappears when using SectionIndexer at specific sections on HoneyComb

Question

I'm using adapter for ListView that implements SectionIndexer. ListView has fastScrollEnabled set to true in xml file. Everything works great on Android 2.2 and 2.3, but when I test my application on a tablet with Android 3.0, at some sections scrollbar disappears. For example when I scroll down the list, at elements beginning with letters A-B scrollbar is visible, but for letters C-H it's not, and then after H again visible.

This adapter is made for sorting content alphabetically in ListView so that fastscroll can be used.

Application is designed for API Level 8, so I couldn't use fastScrollAlwaysVisible.

Here is a code of my adapter:

public class AlphabetSimpleAdapter extends SimpleAdapter implements SectionIndexer {

    private HashMap<String, Integer> charList;
    private String[] alphabet;
    public Typeface tfSansMedium;
    public Context mContext; 
    public int mResource;
    public int[] mTo;
    public List<? extends Map<String, ?>> mData;
    public String mTitleKey;

    public AlphabetSimpleAdapter(Context context,
            List<? extends Map<String, ?>> data, int resource, String[] from,
            int[] to, String titleKey /* key sent in hashmap */) {
        super(context, data, resource, from, to);
        mData = data;
        mTitleKey = titleKey;
        mContext = context;
        mResource = resource;
        mTo = new int[to.length];
        for ( int i = 0; i < to.length; i ++)
        {
            mTo[i] = to[i];
        }
        charList = new HashMap<String, Integer>();
        int size = data.size();
        tfSansMedium = Typeface.createFromAsset(context.getAssets(), "fonts/VitesseSans-Medium.otf");
        for(int i = 0; i < size; i++) {
                        // Parsing first letter of hashmap element
            String ch = data.get(i).get(titleKey).toString().substring(0, 1); 
            ch = ch.toUpperCase();

            if(!charList.containsKey(ch)) {
                charList.put(ch, i); // Using hashmap to avoid duplicates
            }
        }

        Set<String> sectionLetters = charList.keySet(); // A set of all first letters

        ArrayList<String> sectionList = new ArrayList<String>(sectionLetters); // Creating arraylist to be able to sort elements
        Collections.sort(sectionList, Collator.getInstance(new Locale("pl", "PL"))); // Sorting elements
        alphabet = new String[sectionList.size()];
        sectionList.toArray(alphabet);

    }

    // Methods required by SectionIndexer

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View v = convertView;
        if (v == null) {
            LayoutInflater li = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            v = li.inflate(mResource, null);
        }
        for (int i = 0; i < mTo.length; i ++) {
            TextView tv = (TextView)v.findViewById(mTo[i]);
            if (tv != null) tv.setTypeface(tfSansMedium);
        }
        return super.getView(position, v, parent);
    }

    @Override
    public int getPositionForSection(int section) {
        if(!(section > alphabet.length-1)) {
            return charList.get(alphabet[section]);
        }
        else {
            return charList.get(alphabet[alphabet.length-1]);
        }
    }

    @Override
    public int getSectionForPosition(int position) {
        return charList.get(mData.get(position).get(mTitleKey).toString().substring(0, 1));
    }

    @Override
    public Object[] getSections() {
        return alphabet;
    }
}

charList is a HashMap where I store letters with their last appearing index so when I have 6 elements starting with letter "A", the value for key "A" is 5 and so on.

alphabet is a String array with all existing first letters.

Answer 1

I was facing same problem. I just gave my minimum SDK version as 8 and traget as 16 and wrote the code below. And everything worked fine.

             int currentapiVersion = android.os.Build.VERSION.SDK_INT;
                 if (currentapiVersion <= android.os.Build.VERSION_CODES.FROYO){
                     // Do something for froyo and above versions
                     fblist.setFastScrollEnabled(true);


                 } else if(currentapiVersion > android.os.Build.VERSION_CODES.HONEYCOMB){
                     // do something for phones running an SDK before froyo
                     fblist.setFastScrollEnabled(true);
                     fblist.setFastScrollAlwaysVisible(true);
                 }