FrameLayout--霓虹灯

package com.example.framelayout

import android.support.v7.app.AppCompatActivity

import android.os.Bundle

import android.os.Handler

import android.os.Message

import android.widget.TextView

import java.lang.ref.WeakReference

import java.util.*

class MainActivity : AppCompatActivity() {

    internal val names = intArrayOf(R.id.view01,R.id.view02,R.id.view03,R.id.view04,R.id.view05,R.id.view06)

    private var views = arrayOfNulls<TextView>(names.size)

    private var handler:Handler = MyHandler(WeakReference(this))

    override fun onCreate(savedInstanceState: Bundle?) {

        super.onCreate(savedInstanceState)

        setContentView(R.layout.activity_main)

        for(i in names.indices)

        {

            views[i]=findViewById(names[i])

        }

        //定义一个线程，周期改变textView的背景色

        Timer().schedule(object:TimerTask()

        {

            override fun run()

            {

                //发送一条消息通知系统改变背景色

                handler.sendEmptyMessage(0x123)

            }

        },0,200)

    }

    class MyHandler(private val activity: WeakReference<MainActivity>):Handler()

    {

        private var cur =0

        //定义一个颜色数组

        internal var colors = intArrayOf(R.color.color1,

            R.color.color2,

            R.color.color3,R.color.color4,R.color.color5,R.color.color6)

        override fun handleMessage(msg: Message?) {

            if(msg?.what==0x123)

            {

                for(i in activity.get()?.names?.indices!!)

                {

                    activity.get()?.views!![i]?.setBackgroundResource(colors[(i+cur)%colors.size])

                }

                cur++

            }

            super.handleMessage(msg)

        }

    }

}

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

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:app="http://schemas.android.com/apk/res-auto"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".MainActivity">

    <TextView

            android:id="@+id/view01"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="center"

            android:width="320dp"

            android:height="320dp"

            android:background="@color/color1"

    />

    <TextView

            android:id="@+id/view02"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="center"

            android:width="280dp"

            android:height="280dp"

            android:background="@color/color2"

    />

    <TextView

            android:id="@+id/view03"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="center"

            android:width="240dp"

            android:height="240dp"

            android:background="@color/color3"

    />

    <TextView

            android:id="@+id/view04"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="center"

            android:width="200dp"

            android:height="200dp"

            android:background="@color/color4"

    />

    <TextView

            android:id="@+id/view05"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="center"

            android:width="160dp"

            android:height="160dp"

            android:background="@color/color5"

    />

    <TextView

            android:id="@+id/view06"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="center"

            android:width="120dp"

            android:height="120dp"

            android:background="@color/color5"

    />

</FrameLayout>