Android实现旋转木马的音乐效果

public class MainActivity extends Activity {
  MediaPlayer m1;
  ImageView infoOperatingIV;
 
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    infoOperatingIV = (ImageView) findViewById(R.id.infoOperating);
 
    Button play = (Button) findViewById(R.id.play);
    Button stop = (Button) findViewById(R.id.stop);
 
    play.setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        playMusic();
      }
    });
 
    stop.setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        stopMusic();
      }
    });
 
  }
 
  private void playMusic() {
    m1 = MediaPlayer.create(this, R.raw.quiet);
    m1.start();
 
    Animation operatingAnim = AnimationUtils.loadAnimation(this, R.anim.tip);
    LinearInterpolator lin = new LinearInterpolator();
    operatingAnim.setInterpolator(lin);
    if (operatingAnim != null) {
      infoOperatingIV.startAnimation(operatingAnim);
    }
 
    m1.setOnCompletionListener(new OnCompletionListener() {
      @Override
      public void onCompletion(MediaPlayer mp) {
        mp.stop();
        infoOperatingIV.clearAnimation();
      }
    });
  }
 
  private void stopMusic() {
    m1.stop();
    infoOperatingIV.clearAnimation();
  }
 
}

  public class RoundImageView extends ImageView {
  private int mBorderThickness = 0;
  private Context mContext;
  private int defaultColor = 0xFFFFFFFF;
  // 如果只有其中一个有值，则只画一个圆形边框
  private int mBorderOutsideColor = 0;
  private int mBorderInsideColor = 0;
  // 控件默认长、宽
  private int defaultWidth = 0;
  private int defaultHeight = 0;
 
  public RoundImageView(Context context) {
    super(context);
    mCOntext= context;
  }
 
  public RoundImageView(Context context, AttributeSet attrs) {
    super(context, attrs);
    mCOntext= context;
    setCustomAttributes(attrs);
  }
 
  public RoundImageView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    mCOntext= context;
    setCustomAttributes(attrs);
  }
 
  private void setCustomAttributes(AttributeSet attrs) {
    TypedArray a = mContext.obtainStyledAttributes(attrs, R.styleable.roundedimageview);
    mBorderThickness = a.getDimensionPixelSize(R.styleable.roundedimageview_border_thickness, 0);
    mBorderOutsideColor = a.getColor(R.styleable.roundedimageview_border_outside_color, defaultColor);
    mBorderInsideColor = a.getColor(R.styleable.roundedimageview_border_inside_color, defaultColor);
  }
 
  @Override
  protected void onDraw(Canvas canvas) {
    Drawable drawable = getDrawable();
    if (drawable == null) {
      return;
    }
 
    if (getWidth() == 0 || getHeight() == 0) {
      return;
    }
    this.measure(0, 0);
    if (drawable.getClass() == NinePatchDrawable.class)
      return;
    Bitmap b = ((BitmapDrawable) drawable).getBitmap();
    Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);
    if (defaultWidth == 0) {
      defaultWidth = getWidth();
 
    }
    if (defaultHeight == 0) {
      defaultHeight = getHeight();
    }
    // 保证重新读取图片后不会因为图片大小而改变控件宽、高的大小（针对宽、高为wrap_content布局的imageview，但会导致margin无效）
    // if (defaultWidth != 0 && defaultHeight != 0) {
    // LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
    // defaultWidth, defaultHeight);
    // setLayoutParams(params);
    // }
    int radius = 0;
    if (mBorderInsideColor != defaultColor && mBorderOutsideColor != defaultColor) {// 定义画两个边框，分别为外圆边框和内圆边框
      radius = (defaultWidth  bmpWidth) {// 高大于宽
      squareWidth = squareHeight = bmpWidth;
      x = 0;
      y = (bmpHeight - bmpWidth) / 2;
      // 截取正方形图片
      squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth, squareHeight);
    } else if (bmpHeight