[移动开发]霓虹灯的效果

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

    <!-- 依次定义7个TextView，先定义的TextView位于底层
     后定义的TextView位于上层-->
    <TextView
        android:id="@+id/view1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:width="210dp"
        android:height="50dp"
        android:background="#ff0000"
        />
    <TextView
        android:id="@+id/view2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:width="180dp"
        android:height="50dp"
        android:background="#dd0000"
        />
    <TextView
        android:id="@+id/view3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:width="150dp"
        android:height="50dp"
        android:background="#bb0000"
        />
    <TextView
        android:id="@+id/view4"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:width="120dp"
        android:height="50dp"
        android:background="#990000"
        />
    <TextView
        android:id="@+id/view5"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:width="90dp"
        android:height="50dp"
        android:background="#770000"
        />
    <TextView
        android:id="@+id/view6"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:width="60dp"
        android:height="50dp"
        android:background="#550000"
        />
    <TextView
        android:id="@+id/view7"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:width="30dp"
        android:height="50dp"
        android:background="#330000"
        />
</FrameLayout>

<?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">#FF0000</color>
    <color name="color2">#dd0000</color>
    <color name="color3">#bb0000</color>
    <color name="color4">#990000</color>
    <color name="color5">#770000</color>
    <color name="color6">#550000</color>
    <color name="color7">#330000</color>


</resources>

package com.example.shangqiuju.myapplication;

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.widget.TextView;

import java.util.Timer;
import java.util.TimerTask;

/**
 * Created by shangqiuju on 2021/7/30.
 */

public class FrameLayoutColor extends AppCompatActivity {
    private int currentColor = 0;
    //定义一个颜色数组
    final int[] colors = new int[]{
            R.color.color7,
            R.color.color6,
            R.color.color5,
            R.color.color4,
            R.color.color3,
            R.color.color2,
            R.color.color1
    };
    final int[] names = new int[]{
            R.id.view1,
            R.id.view2,
            R.id.view2,
            R.id.view3,
            R.id.view4,
            R.id.view5,
            R.id.view6,
            R.id.view7
    };
    TextView[] views = new TextView[7];

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.frame_layout);
        for(int i = 0;i < 7; i++){
            views[i] = (TextView)findViewById(names[i]);
        }
        final Handler handler = new Handler(){
            @Override
            public void handleMessage(Message msg) {
                //表明消息来自本程序所发送
                if(msg.what == 0x1122){
                    //依次改变7个TextView 的背景色
                    for(int i = 0 ;i < 7 - currentColor;i++){
                        views[i].setBackgroundResource(colors[i + currentColor]);
                    }
                    for(int i = 7 - currentColor,j = 0 ; i < 7; i++,j++){
                        views[i].setBackgroundResource(colors[i]);
                    }
                }
                super.handleMessage(msg);
            }
        };
        //定义一个线程周期性的改变currentColor变量值
        new Timer().schedule(new TimerTask() {
            @Override
            public void run() {
                currentColor++;
                if(currentColor >= 6){
                    currentColor = 0;
                }
                //发送一条消息通知系统改变7个TextView组件的背景色
                Message m = new Message();
                //给该消息定义一个标识
                m.what = 0x1122;
                handler.sendMessage(m);
            }
        },0,100);

    }
}