如何在Android中创建LED文本滚动条的背景？

public class LEDTextView extends TextView {
    private String text;
    private int scrollSpeed;

    public LEDTextView(Context context) {
        super(context);
        init();
    }

    public LEDTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public LEDTextView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        text = "Hello LED";
        scrollSpeed = 5; // 滚动速度，可根据需求调整
    }

    @Override
    protected void onDraw(Canvas canvas) {
        // 绘制背景颜色或背景图片
        canvas.drawColor(Color.BLACK);

        Paint paint = new Paint();
        paint.setColor(Color.GREEN);
        paint.setTextSize(50);

        float textWidth = paint.measureText(text);
        float x = getScrollX() % (getWidth() + textWidth);

        // 绘制文本，实现滚动效果
        canvas.drawText(text, x - textWidth, getHeight() / 2, paint);
        canvas.drawText(text, x, getHeight() / 2, paint);

        // 刷新视图，实现动画效果
        invalidate();
    }
}

<com.example.LEDTextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Hello LED"
    android:textSize="50sp" />