Can't create handler inside thread that has not called Looper.prepare()怎么解决？

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Can't create handler inside thread that has not called Looper.prepare()怎么解决？5

绘制小球，当小球触底或触顶时自动改变方向继续运行
代码如下：
package com.amaker.test.app;

import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Bundle;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.Looper;
import android.os.Message;
import android.util.AttributeSet;
import android.view.View;

public class MainActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
MyView v = new MyView(this, null);
setContentView(v);
}
// 自定义视图类
class MyView extends View implements Runnable {
// 图形当前坐标
private int x = 20, y = 20;
// 构造方法
public MyView(Context context, AttributeSet attrs) {
super(context, attrs);
// 获得焦点
setFocusable(true);
// 启动线程
new Thread(this).start();
}
@Override
public void run() {
RefreshHandler mRedrawHandler = new RefreshHandler();

while (!Thread.currentThread().isInterrupted()) {
// 通过发送消息更新界面
Message m = new Message();
m.what = 0x101;
mRedrawHandler.sendMessage(m);
try {
Thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}

@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
// 实例化画笔
Paint p = new Paint();
// 设置画笔颜色
p.setColor(Color.GREEN);
// 画圆
canvas.drawCircle(x, y, 10, p);
}

// 更新界面处理器
class RefreshHandler extends Handler {

/*public RefreshHandler(){}
public RefreshHandler(Looper looper){
super(looper);
}*/
public void handleMessage(Message msg) {
if (msg.what == 0x101) {
MyView.this.update();
MyView.this.invalidate();
}

super.handleMessage(msg);
}
};

// 更新坐标
private void update() {
int h = getHeight();
y += 5;
if (y >= h)
y = 20;
}
}
}