android - Highlight searched text in ListView items

Question

I have a ListView and i am using a custom adapter to show data. Now i want to change searched text letter colour as in above screen shot.

Here is the code for SearchView

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.actionbar_menu_item, menu);
    SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
    final SearchView searchView = (SearchView) menu.findItem(R.id.action_search)
            .getActionView();
    searchView.setSearchableInfo(searchManager
            .getSearchableInfo(getComponentName()));
    searchView.setOnQueryTextListener(this);
        return super.onCreateOptionsMenu(menu);
        }

public boolean onQueryTextChange(String newText) {
    // this is adapter that will be filtered
      if (TextUtils.isEmpty(newText)){
            lvCustomList.clearTextFilter();
      }
      else{
            lvCustomList.setFilterText(newText.toString());
       }
    return false;
 }

@Override
public boolean onQueryTextSubmit(String query) {
    return false;
}

Thank you.

Answer 1

I assume that you have a custom Adapter with getCount() and getView() implemented and already filtering items, and you just need the bold part.

To achieve that, you need to use a SpannableString, which is basically text with markup attached. For example, a TextAppearanceSpan can be used to change typeface, font style, size, and color.

So, you should update your adapter's getView() to change the part where you use textView.setText() into something more or less like this:

String filter = ...;
String itemValue = ...;

int startPos = itemValue.toLowerCase(Locale.US).indexOf(filter.toLowerCase(Locale.US));
int endPos = startPos + filter.length();

if (startPos != -1) // This should always be true, just a sanity check
{
    Spannable spannable = new SpannableString(itemValue);
    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);
    textView.setText(spannable);
}
else
    textView.setText(itemValue);