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androidandroid-layoutandroid-fragmentstextviewandroid-search

how do I highlight the searched text in my search filter?


I am trying to do a search such that all the "visible" search letters should be highlighted. I tried using spannable but that didn't do the trick, maybe I wasnt doing it right? based on this: Highlight searched text in ListView items How do i get to highlight the visible text? here's my filter :

private LayoutInflater mInflater;

        private ValueFilter valueFilter;

        public MySimpleArrayAdapter(Activity context) {

            this.context = context;
            mInflater = LayoutInflater.from(context);

        }
        private class ValueFilter extends Filter {


            //Invoked in a worker thread to filter the data according to the constraint.
            @Override
            protected synchronized FilterResults performFiltering(CharSequence constraint) {

                FilterResults results = new FilterResults();

                if (constraint != null && constraint.length() > 0) {

                    ArrayList<Integer> filterList = new ArrayList<>();

                    int iCnt = listItemsHolder.Names.size();
                    for (int i = 0; i < iCnt; i++) {
                        if(listItemsHolder.Types.get(i).toString().indexOf("HEADER_")>-1){
                            continue;
                        }
                        if (listItemsHolder.Names.get(i).matches(getRegEx(constraint))||(listItemsHolder.Names.get(i).toLowerCase().contains(constraint.toString().toLowerCase()))) {
                            if(filterList.contains(i))
                                continue;

                            filterList.add(i);

                        }
                        }

                    results.count = filterList.size();

                    results.values = filterList;
                }else {
                String prefixString = getRegEx(constraint);
                mSearchText = prefixString;
                    results.count = listItemsHolder.Names.size();

                    ArrayList<Integer> tList = new ArrayList<>();
                    for(int i=0;i<results.count;i++){
                        tList.add(i);
                    }

                    results.values = tList;

                }

                return results;


}


                //Invoked in the UI thread to publish the filtering results in the user interface.
                @SuppressWarnings("unchecked")
                @Override
                protected void publishResults(CharSequence constraint, FilterResults results) {
                    ArrayList<Integer> resultsList = (ArrayList<Integer>)results.values;
                    if(resultsList != null) {
                        m_filterList = resultsList;
                    }
                    notifyDataSetChanged();
                }

            }

            public String getRegEx(CharSequence elements){
                String result = "(?i).*";
                for(String element : elements.toString().split("\\s")){
                    result += element + ".*";
                }
                result += ".*";
                return result;
            }

Thanks in advance! 

Here's my getview

@Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View rowView = convertView;
            ViewHolder holder;
            if(filtering && m_filterList != null && m_filterList.size() > position)
                position = m_filterList.get(position);

            if (rowView == null) {
                holder = new ViewHolder();

                mInflater = context.getLayoutInflater();
                rowView = mInflater.inflate(R.layout.rowlayout, null);
                // configure view holder
                holder.text = (TextView) rowView.findViewById(R.id.label);
                holder.text.setTextColor(Color.WHITE);
                holder.text.setSingleLine();
                holder.text.setTextSize(15);
                holder.text.setEllipsize(TextUtils.TruncateAt.END);
                holder.text.setPadding(2, 2, 6, 2);
                Typeface label = Typeface.createFromAsset(holder.text.getContext().getAssets(),
                        "fonts/arial-bold.ttf");
                holder.text.setTypeface(label);
                holder.image = (ImageView) rowView.findViewById(R.id.icon);
                holder.image.setPadding(6, 4, 0, 4);
                holder.image.getLayoutParams().height = (int) getResources().getDimension(R.dimen.icon_width_height);
                holder.image.getLayoutParams().width = (int) getResources().getDimension(R.dimen.icon_width_height);
                rowView.setBackgroundResource(R.drawable.row_border);
                rowView.setPadding(2, 2, 6, 2);
                rowView.setTag(holder);
            }else {

                // fill data
                holder = (ViewHolder) rowView.getTag();
            }

            String id  = listItemsHolder.getid(position);
            String name = listItemsHolder.getName(position);
            holder.image.setVisibility(View.VISIBLE);


            if (name != null) {
                holder.text.setText(listItemsHolder.getName(position));
                ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams) holder.text.getLayoutParams();
                params.leftMargin = 20;
            }else{
                holder.text.setText(id);
            }
            String fullText = listItemsHolder.getName(position);
            // highlight search text
            if (mSearchText != null && !mSearchText.isEmpty()) {
                int startPos = fullText.toLowerCase(Locale.US).indexOf(mSearchText.toLowerCase(Locale.US));
                int endPos = startPos + mSearchText.length();
                if (startPos != -1) {
                    Spannable spannable = new SpannableString(fullText);
                    ColorStateList blueColor = new ColorStateList(new int[][]{new int[]{}}, new int[]{Color.BLUE});
                    TextAppearanceSpan highlightSpan = new TextAppearanceSpan(null, Typeface.BOLD, -1, blueColor, null);
                    spannable.setSpan(highlightSpan, startPos, endPos, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
                    holder.text.setText(spannable);
                } else {
                    holder.text.setText(fullText);
                }
            } else {
                holder.text.setText(fullText);
            }
            return rowView;
        }

Solution

  • Let's assume you have create a custom adapter, then you can refer to the following code:

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View view;
            TextView text;
    
            if (convertView == null) {
                view = mInflater.inflate(mResource, parent, false);
            } else {
                view = convertView;
            }
    
            try {
                if (mFieldId == 0) {
                    //  If no custom field is assigned, assume the whole resource is a TextView
                    text = (TextView) view;
                } else {
                    //  Otherwise, find the TextView field within the layout
                    text = (TextView) view.findViewById(mFieldId);
                }
            } catch (ClassCastException e) {
                Log.e("ArrayAdapter", "You must supply a resource ID for a TextView");
                throw new IllegalStateException(
                        "ArrayAdapter requires the resource ID to be a TextView", e);
            }
            String item = getItem(position);
            text.setText(item);
    
            String fullText = getItem(position);
            // highlight search text
            if (mSearchText != null && !mSearchText.isEmpty()) {
                int startPos = fullText.toLowerCase(Locale.US).indexOf(mSearchText.toLowerCase(Locale.US));
                int endPos = startPos + mSearchText.length();
    
                if (startPos != -1) {
                    Spannable spannable = new SpannableString(fullText);
                    ColorStateList blueColor = new ColorStateList(new int[][]{new int[]{}}, new int[]{Color.BLUE});
                    TextAppearanceSpan highlightSpan = new TextAppearanceSpan(null, Typeface.BOLD, -1, blueColor, null);
                    spannable.setSpan(highlightSpan, startPos, endPos, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
                    text.setText(spannable);
                } else {
                    text.setText(fullText);
                }
            } else {
                text.setText(fullText);
            }
    
            return view;
        }
    

    The mSearchText will be updated at the following inside performFiltering of ArrayFilter class.

    String prefixString = prefix.toString().toLowerCase();
    mSearchText = prefixString;
    

    You can find more details in my sample code here or my GitHub (with lastest update).

    Here is the screenshot

    enter image description here