android之AutoCompleteTextView控件用法

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/container"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    tools:context="com.example.mar_2300_autocompletetextview.MainActivity"
    tools:ignore="MergeRootFrame" >
<AutoCompleteTextView android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:id="@+id/atv"/>
<TextView android:id="@+id/textView1"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"/>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string name="app_name">Mar_2300_AutoCompleteTextView</string>
    <string name="hello_world">Hello world!</string>
    <string name="action_settings">Settings</string>

    <string-array name="test">
        <item>Mercury</item>
        <item>Mercury2</item>
        <item>Venus</item>
        <item>Earth</item>
        <item>Mars</item>
        <item>Jupiter</item>
        <item>Saturn</item>
        <item>Uranus</item>
        <item>Neptune</item>
    </string-array>

</resources>

package com.example.mar_2300_autocompletetextview;

import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.text.Editable;
import android.text.TextWatcher;
import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.AutoCompleteTextView;
import android.widget.TextView;
import android.os.Build;

public class MainActivity extends Activity implements TextWatcher {
    private AutoCompleteTextView atv;
    private TextView tv;
    private ArrayAdapter<CharSequence> adapter;

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

    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count,
            int after) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        // TODO Auto-generated method stub
        tv.setText(atv.getText());
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        atv = (AutoCompleteTextView) findViewById(R.id.atv);
        tv = (TextView) findViewById(R.id.textView1);
        adapter = ArrayAdapter.createFromResource(this, R.array.test,
                android.R.layout.simple_dropdown_item_1line);
        atv.setAdapter(adapter);
        atv.addTextChangedListener(this);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}