Kotlin02.frameLayout霓虹灯效果

MainActivity.kt

package com.example.framelayout

import androidx.appcompat.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)

    class MyHandler(private val activity : WeakReference<MainActivity>) : Handler(){
        private var currentColor = 0;
        internal val 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 + currentColor) % colors.size]
                    )
                }
                currentColor++
            }
            super.handleMessage(msg)
        }
    }
    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])
        }
        Timer().schedule(object : TimerTask(){
            override fun run() {
                handler.sendEmptyMessage(0x123)
            }
        },0, 200)
    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <!-- 依次定义6个TextView，先定义的TextView位于底层，
        后定义的TextView位于上层 -->
    <TextView
        android:id="@+id/view01"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:width="160pt"
        android:height="160pt"
        android:background="#f00"/>
    <TextView
        android:id="@+id/view02"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:width="140pt"
        android:height="140pt"
        android:background="#0f0"/>
    <TextView
        android:id="@+id/view03"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:width="120pt"
        android:height="120pt"
        android:background="#00f"/>
    <TextView
        android:id="@+id/view04"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:width="100pt"
        android:height="100pt"
        android:background="#ff0"/>
    <TextView
        android:id="@+id/view05"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:width="80pt"
        android:height="80pt"
        android:background="#f0f"/>
    <TextView
        android:id="@+id/view06"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:width="60pt"
        android:height="60pt"
        android:background="#0ff"/>
</FrameLayout>

colors.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="colorPrimary">#3F51B5</color>
    <color name="colorPrimaryDark">#303F9F</color>
    <color name="colorAccent">#FF4081</color>
    <color name="color1">#f00</color>
    <color name="color2">#0f0</color>
    <color name="color3">#00f</color>
    <color name="color4">#ff0</color>
    <color name="color5">#f0f</color>
    <color name="color6">#0ff</color>
</resources>

效果图

本文地址：https://blog.csdn.net/augfun/article/details/107881839