<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="match_parent">

    <!-- 定义一个自动完成文本框，指定输入一个字符后进行提示 -->
    <AutoCompleteTextView
        android:id="@+id/auto_actv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="输入联系人姓名"
        android:completionHint="选择联系人"
        android:dropDownHorizontalOffset="10dp"
        android:completionThreshold="1"/>

    <!-- 定义一个MultiAutoCompleteTextView组件 -->
    <MultiAutoCompleteTextView
        android:id="@+id/mauto_mactv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="输入联系人姓名，可多个分隔符分隔"
        android:completionThreshold="1"/>
</LinearLayout>

package com.jinyu.cqkxzsxy.android.listviewsample;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.ArrayAdapter;
import android.widget.AutoCompleteTextView;
import android.widget.MultiAutoCompleteTextView;

public class AutoCompleteTextViewActivity extends AppCompatActivity {
    private AutoCompleteTextView mAutoTv = null;
    private MultiAutoCompleteTextView mMultiAutoTv = null;

    // 定义字符串数组，作为提示的文本
    private String[] mContacts = new String[]{
            "test", "abc", "aaa", "aabbcc", "bac", "ok", "say", "aabbsd"
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.autocomplete_textview_layout);
        mAutoTv = (AutoCompleteTextView)findViewById(R.id.auto_actv);
        mMultiAutoTv = (MultiAutoCompleteTextView)findViewById(R.id.mauto_mactv);

        // 创建一个ArrayAdapter，封装数组
        ArrayAdapter<String> aa = new ArrayAdapter<String>(this,
                android.R.layout.simple_dropdown_item_1line, mContacts);

        // 设置Adapter
        mAutoTv.setAdapter(aa);
        mMultiAutoTv.setAdapter(aa);

        // 为MultiAutoCompleteTextView设置分隔符
        mMultiAutoTv.setTokenizer(new MultiAutoCompleteTextView.CommaTokenizer());
    }
}