<?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"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:completionHint="请选择您喜欢的图书："

        android:dropDownHorizontalOffset="10dp"

        android:completionThreshold="1"/>

    <!-- 定义一个MultiAutoCompleteTextView组件 -->

    <MultiAutoCompleteTextView

        android:id="@+id/mauto"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:completionThreshold="1"/>

</LinearLayout>

package com.example.autocompletetextview

import android.support.v7.app.AppCompatActivity

import android.os.Bundle

import android.widget.ArrayAdapter

import android.widget.AutoCompleteTextView

import android.widget.MultiAutoCompleteTextView

class MainActivity : AppCompatActivity() {

    // 定义字符串数组，作为提示的文本

    private var books = arrayOf("aaaa", "abbbbbbb",

        "abcccccccccc", "ccccccccc")

    override fun onCreate(savedInstanceState: Bundle?) {

        super.onCreate(savedInstanceState)

        setContentView(R.layout.activity_main)

        // 创建一个ArrayAdapter，封装数组

        val aa = ArrayAdapter(this, android.R.layout.simple_dropdown_item_1line, books)

        val actv = findViewById<AutoCompleteTextView>(R.id.auto)

        // 设置Adapter

        actv.setAdapter(aa)

        val mauto = findViewById<MultiAutoCompleteTextView>(R.id.mauto)

        // 设置Adapter

        mauto.setAdapter(aa)

        // 为MultiAutoCompleteTextView设置分隔符

        mauto.setTokenizer(MultiAutoCompleteTextView.CommaTokenizer())

    }

}