edittext 监听内容变化

给EditText追加ChangedListener可以监听EditText内容变化的监听

如图是效果图  类似于过滤的一种实现

1  布局也就是一个EditText，当EditText内容发生变化时（当输入数字时）就会出现一个PopupWindow通过ChangedListener来显示监听

2 数据是进入这个页面就加载出来的，当输入的内容变化时，通过遍历改变

3 字体颜色的变化http://www.cnblogs.com/sinber/archive/2011/10/27/2227012.html

Demo下载地址：http://download.csdn.net/detail/qq_29774291/9728733

如下是主要代码：

package com.item.demo;

import java.util.ArrayList;
import java.util.List;

import android.os.Bundle;
import android.text.Editable;
import android.text.SpannableString;
import android.text.Spanned;
import android.text.TextWatcher;
import android.text.style.ForegroundColorSpan;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.EditText;
import android.widget.LinearLayout.LayoutParams;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.PopupWindow;
import android.widget.TextView;
import android.app.Activity;
import android.content.Context;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;

/**
 * EditText的一个Demo 实现EditText + PopupWindow来实现搜索的功能
 *
 * @author Administrator
 *
 */
public class MainActivity extends Activity {
    private PopupWindow popupWindow;
    private ListView lView;
    private MyAdapter adapter;
    private EditText edtText;
    private List<String> list = new ArrayList<String>();
    private List<SpannableString> carNumber = new ArrayList<SpannableString>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        edtText = (EditText) findViewById(R.id.edt_hello);
        initData();
        adapter = new MyAdapter(this, carNumber);
        edtText.addTextChangedListener(new TextWatcher() {

            @Override
            public void onTextChanged(CharSequence s, int arg1, int arg2, int arg3) {
                // TODO Auto-generated method stub
                if(s.length() > 0){
                    if(popupWindow == null){
                        View contentView = View.inflate(MainActivity.this, R.layout.item_list, null);
                        lView = (ListView)contentView.findViewById(R.id.item_list);
                        popupWindow = new PopupWindow(contentView,edtText.getWidth(),LayoutParams.WRAP_CONTENT,true);
                    }
                    carNumber.clear();
                    for(String str : list){
                        if(str.startsWith("" + s)){
                            SpannableString ss = new SpannableString(str);
                            ss.setSpan(new ForegroundColorSpan(Color.BLUE), 0, s.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
                            carNumber.add(ss);
                        }
                    }
                    if(carNumber.size() == 0){
                        SpannableString ssString = new SpannableString("无该车牌号");
                        ssString.setSpan(new ForegroundColorSpan(Color.RED), 0, ssString.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
                        carNumber.add(ssString);
                    }
                    adapter.notifyDataSetChanged();
                    lView.setAdapter(adapter);
                    popupWindow.setOutsideTouchable(true);
                    popupWindow.setFocusable(false);
                    popupWindow.setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
                    popupWindow.showAsDropDown(edtText, 0, 0);
                    if(carNumber.size() >=5){
                        popupWindow.update(edtText.getWidth(), 250);
                    }else {
                        popupWindow.update(edtText.getWidth(), LayoutParams.WRAP_CONTENT);
                    }
                    lView.setOnItemClickListener(new OnItemClickListener() {

                        @Override
                        public void onItemClick(AdapterView<?> arg0, View arg1,
                                int arg2, long arg3) {
                            // TODO Auto-generated method stub
                            edtText.setText(carNumber.get(arg2).toString());
                            if(popupWindow !=null && popupWindow.isShowing()){
                                popupWindow.dismiss();
                            }
                        }
                    });
                }
            }

            @Override
            public void beforeTextChanged(CharSequence arg0, int arg1, int arg2,
                    int arg3) {
                // TODO Auto-generated method stub

            }

            @Override
            public void afterTextChanged(Editable arg0) {
                // TODO Auto-generated method stub

            }
        });
    }
    /**
     * 模拟数据
     */
    private void initData(){
        list.add("皖A0000");
        list.add("皖A1000");
        list.add("皖A1100");
        list.add("皖A1110");
        list.add("皖A1111");
        list.add("皖A2000");
        list.add("皖A2100");
        list.add("皖A2110");
        list.add("皖A2111");
        list.add("皖A2200");
        list.add("皖A2201");
        list.add("皖A2210");
        list.add("皖A2211");
        list.add("皖A2223");
        list.add("皖A3000");
        list.add("皖A4030");
        list.add("皖A5000");
        list.add("皖A6200");
        list.add("皖A7060");
        list.add("皖A8070");
        list.add("皖A9000");
    }
    /**
     * 适配器
     * @author Administrator
     *
     */
    private class MyAdapter extends BaseAdapter{
        private Context context;
        private List<SpannableString> carList;

        public MyAdapter(Context context, List<SpannableString> carList) {
            super();
            this.context = context;
            this.carList = carList;
        }

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

        @Override
        public Object getItem(int arg0) {
            // TODO Auto-generated method stub
            return null;
        }

        @Override
        public long getItemId(int arg0) {
            // TODO Auto-generated method stub
            return 0;
        }

        @Override
        public View getView(int arg0, View arg1, ViewGroup arg2) {
            // TODO Auto-generated method stub
            ViewHoler holer = null;
            if(arg1 == null) {
                holer = new ViewHoler();
                arg1 = View.inflate(context, R.layout.item_adpter, null);
                holer.tv_name = (TextView)arg1.findViewById(R.id.item_carnum);
                arg1.setTag(holer);
            }else {
                holer = (ViewHoler)arg1.getTag();
            }
            holer.tv_name.setText(carList.get(arg0));
            return arg1;
        }
        class ViewHoler{
            private TextView tv_name;
        }
    }

}