AtTokenizer.java

package com.mcxiaoke.minicat.adapter;

import android.text.SpannableString;
import android.text.Spanned;
import android.text.TextUtils;
import android.widget.MultiAutoCompleteTextView.Tokenizer;

/**
 * AtTokenizer allows for auto-completion of user names starting with an @ sign.
 */
public class AtTokenizer implements Tokenizer {

    @Override
    public int findTokenStart(CharSequence text, int cursor) {
        int i = cursor;
        while (i > 0 && text.charAt(i - 1) != '@')
            i--;
        while (i < cursor && text.charAt(i) == ' ')
            i++;
        return i;
    }

    @Override
    public int findTokenEnd(CharSequence text, int cursor) {
        int i = cursor;
        int len = text.length();
        while (i < len) {
            if (text.charAt(i) == '@') {
                return i;
            } else {
                i++;
            }
        }
        return len;
    }

    @Override
    public CharSequence terminateToken(CharSequence text) {
        int i = text.length();
        while (i > 0 && text.charAt(i - 1) == ' ')
            i--;
        if (i > 0 && text.charAt(i - 1) == '@') {
            return text;
        } else {
            if (text instanceof Spanned) {
                SpannableString sp = new SpannableString(text);
                TextUtils.copySpansFrom((Spanned) text, 0, text.length(),
                        Object.class, sp, 0);
                return sp;
            } else {
                return text + " ";
            }
        }
    }
}