SearchView搜索框

//布局
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.sarchview.MainActivity"
    android:orientation="vertical">

    <SearchView
        android:id="@+id/sv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">
    </SearchView>
    <ListView
        android:id="@+id/lv"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
      ></ListView>
</LinearLayout>

//代码块
package com.example.sarchview;

import android.app.Activity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.SearchView;
import android.widget.Toast;
import android.widget.SearchView.OnQueryTextListener;

public class MainActivity extends Activity implements OnQueryTextListener{
    private SearchView sv;
    private ListView lv;
    private String[] mStrings={"aaaaa","bbbbb","ccccc"};

    @Override
    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        lv=(ListView) findViewById(R.id.lv);
        lv.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, mStrings));
        lv.setTextFilterEnabled(true);

        sv=(SearchView) findViewById(R.id.sv);
        //设置该SearchView默认是否自动缩小为图标
        sv.setIconifiedByDefault(false);
        //为该SearchView组件设置事件监听器
        sv.setOnQueryTextListener(this);
        //设置该SearchView显示搜索按钮
        sv.setSubmitButtonEnabled(true);
        //设置该SearchView内默认显示的提示文本
        sv.setQueryHint("查找");
    }

    //单击搜索按钮时激发该方法
    @Override
    public boolean onQueryTextSubmit(String query){
        // TODO Auto-generated method stub
        //实际应用中应该在该方法内执行实际查询
        //此处仅使用Toast显示用户输入的查询内容
        Toast.makeText(this, "您的选择是："+query,Toast.LENGTH_SHORT).show();
        return false;
    }

    //用户输入字符时激发该方法
    @Override
    public boolean onQueryTextChange(String newText) {
        // TODO Auto-generated method stub
        if(TextUtils.isEmpty(newText)){
            //清除ListVIew的过滤
            lv.clearTextFilter();
        }else{
            //使用用户输入的内容对ListView的列表项进行过滤
            lv.setFilterText(newText);
        }
        return true;
    }

}