在 ListView 中突出显示搜索结果 [英] Highlight search results in ListView

问题描述

我有一个带有 String 的 ListView.使用下面的代码，我可以突出显示搜索结果，但用户必须输入单词才能搜索区分大小写.如何实现不区分大小写的搜索结果突出显示，例如原生 Android 联系人搜索?

I have a ListView with Strings. With the below code I can highlight search results, but the user must type the words to search case sensitive. How can I implement a none - case sensitive highlighting of search results for example like the native Android Contact search?

这是我的高亮代码.我扩展了 ArrayAdapter 并实现自定义过滤器以获取要搜索的字符串.在 getView 方法中，我检查 ListView 中的 String 是否包含 prefixString 并突出显示它.

Here is my code for Highlighting. I extend the ArrayAdapter and implement customized filter to get the string to search. In the getView method I check if my String in ListView contains the prefixString and highlight it.

public class HighlightListAdapter extends ArrayAdapter {
    ArrayList<String> objects;
    final Object mLock =new Object();
    private ArrayList<String> mOriginalValues;
    private ArrayFilter filter;
    private String prefixString;
    public AuthorsListAdapter(Context context, int textViewResourceId,  ArrayList<String> objects) {
        super(context, textViewResourceId, objects);
        this.objects = objects;
    }



    class ViewHolder{
        TextView author;

    }

    public View getView(final int position, View convertView, ViewGroup parent){

        // assign the view we are converting to a local variable
        View v = convertView;
        ViewHolder holder = null;

        // first check to see if the view is null. if so, we have to inflate it.
        // to inflate it basically means to render, or show, the view.
        LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        if (v == null) {
            holder = new ViewHolder();
            v = inflater.inflate(R.layout.author_list_item, null);
            holder.author =(TextView) v.findViewById(R.id.author_list_item_text);
            v.setTag(holder);

        }else{
            holder = (ViewHolder) v.getTag();

        }


         final String author = objects.get(position);        
        if (author != null) {


        holder.author.setText(author);
        if(prefixString !=null && prefixString.length()>1){
            String s =  author;



        **if(s.contains(prefixString)){
            String rep = s.replace(prefixString,    "<b><font color=#2825A6>"+ prefixString+ "</font></b>");
            holder.author.setText(Html.fromHtml(rep));
        }** // higlight 



        }

            }

        return v;
    }
    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return objects.size();
    }



     @Override
    public Filter getFilter() {
        // TODO Auto-generated method stub
        if(filter == null){
            filter =new ArrayFilter();
        }
        return filter;
    }



    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return this.objects.get(position);
    }



    private class ArrayFilter extends Filter {
            @Override
            protected FilterResults performFiltering(CharSequence prefix) {
                FilterResults results = new FilterResults();

                if (mOriginalValues == null) {
                    synchronized (mLock) {
                        mOriginalValues = new ArrayList<String>(objects);
                    }
                }

                if (prefix == null || prefix.length() == 0) {
                    ArrayList<String> list;
                    synchronized (mLock) {
                        list = new ArrayList<String>(mOriginalValues);
                    }
                    results.values = list;
                    results.count = list.size();
                } else {
                    **prefixString = prefix.toString();** // get string to search

                    ArrayList<String> values;
                    synchronized (mLock) {
                        values = new ArrayList<String>(mOriginalValues);
                    }

                    final int count = values.size();
                    final ArrayList<String> newValues = new ArrayList<String>();

                    for (int i = 0; i < count; i++) {
                        final String value = values.get(i);
                        final String valueText = value.toString().toLowerCase();

                        // First match against the whole, non-splitted value
                        if (valueText.startsWith(prefixString)) {
                            newValues.add(value);
                        } else {
                            final String[] words = valueText.split(" ");
                            final int wordCount = words.length;

                            // Start at index 0, in case valueText starts with space(s)
                            for (int k = 0; k < wordCount; k++) {
                                if (words[k].startsWith(prefixString)) {
                                    newValues.add(value);
                                    break;
                                }
                            }
                        }
                    }

                    results.values = newValues;
                    results.count = newValues.size();
                }

                return results;
            }
            @SuppressWarnings("unchecked")
            @Override
            protected void publishResults(CharSequence constraint,  FilterResults results) {
                   objects = (ArrayList<String>) results.values;
                if (results.count > 0) {
                                   notifyDataSetChanged();
                               } else {
                                 notifyDataSetInvalidated();
                              }

            }

        };
    }

推荐答案

这就是我使用的:

• 每次出现都被替换(不仅仅是前缀)
• 搜索时会忽略大小写和重音符号，但会保留在结果中.
• 它直接使用SpannableString，您可以在setText() 中使用它.我相信它比使用中间 html 步骤更有效.

• Every occurence is replaced (not only prefix)
• Case and accent are ignored while searching but retained in the result.
• It uses directly SpannableString, which you can use in setText(). I believe it's more efficient than using an intermediate html step.

.

public static CharSequence highlight(String search, String originalText) {
    // ignore case and accents
    // the same thing should have been done for the search text
    String normalizedText = Normalizer.normalize(originalText, Normalizer.Form.NFD).replaceAll("\p{InCombiningDiacriticalMarks}+", "").toLowerCase();

    int start = normalizedText.indexOf(search);
    if (start < 0) {
        // not found, nothing to to
        return originalText;
    } else {
        // highlight each appearance in the original text
        // while searching in normalized text
        Spannable highlighted = new SpannableString(originalText);
        while (start >= 0) {
            int spanStart = Math.min(start, originalText.length());
            int spanEnd = Math.min(start + search.length(), originalText.length());

            highlighted.setSpan(new BackgroundColorSpan(<background_color>), spanStart, spanEnd, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

            start = normalizedText.indexOf(search, spanEnd);
        }

        return highlighted;
    }
}

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