Android实现垂直进度条VerticalSeekBar

/**
 * Class to create a vertical slider
 */
public class VerticalSeekBar extends SeekBar {

  public VerticalSeekBar(Context context) {
    super(context);
  }

  public VerticalSeekBar(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
  }

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

  protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    super.onSizeChanged(h, w, oldh, oldw);
  }

  @Override
  protected synchronized void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(heightMeasureSpec, widthMeasureSpec);
    setMeasuredDimension(getMeasuredHeight(), getMeasuredWidth());
  }

  protected void onDraw(Canvas c) {
    c.rotate(-90);
    c.translate(-getHeight(), 0);

    super.onDraw(c);
  }

  @Override
  public boolean onTouchEvent(MotionEvent event) {
    if (!isEnabled()) {
      return false;
    }

    switch (event.getAction()) {
      case MotionEvent.ACTION_DOWN:
      case MotionEvent.ACTION_MOVE:
      case MotionEvent.ACTION_UP:
        setProgress(getMax() - (int) (getMax() * event.getY() / getHeight()));
        onSizeChanged(getWidth(), getHeight(), 0, 0);
        break;

      case MotionEvent.ACTION_CANCEL:
        break;
    }
    return true;
  }
}

public class VerticalSeekBar2 extends SeekBar {
  private Drawable mThumb;
  private OnSeekBarChangeListener mOnSeekBarChangeListener;

  public VerticalSeekBar2(Context context) {
    super(context);
  }

  public VerticalSeekBar2(Context context, AttributeSet attrs) {
    super(context, attrs);
  }

  public VerticalSeekBar2(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
  }

  public void setOnSeekBarChangeListener(OnSeekBarChangeListener l) {
    mOnSeekBarChangeListener = l;
  }

  protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    super.onSizeChanged(h, w, oldh, oldw);
  }

  @Override
  protected synchronized void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(heightMeasureSpec, widthMeasureSpec);
    setMeasuredDimension(getMeasuredHeight(), getMeasuredWidth());
  }

  protected void onDraw(Canvas c) {
    c.rotate(-90);
    c.translate(-getHeight(), 0);

    super.onDraw(c);
  }

  void onProgressRefresh(float scale, boolean fromUser) {
    Drawable thumb = mThumb;
    if (thumb != null) {
      setThumbPos(getHeight(), thumb, scale, Integer.MIN_VALUE);
      invalidate();
    }
    if (mOnSeekBarChangeListener != null) {
      mOnSeekBarChangeListener.onProgressChanged(this, getProgress(), fromUser);
    }
  }

  private void setThumbPos(int w, Drawable thumb, float scale, int gap) {
    int available = w - getPaddingLeft() - getPaddingRight();

    int thumbWidth = thumb.getIntrinsicWidth();
    int thumbHeight = thumb.getIntrinsicHeight();

    int thumbPos = (int) (scale * available + 0.5f);

    // int topBound = getWidth() / 2 - thumbHeight / 2 - getPaddingTop();
    // int bottomBound = getWidth() / 2 + thumbHeight / 2 - getPaddingTop();
    int topBound, bottomBound;
    if (gap == Integer.MIN_VALUE) {
      Rect oldBounds = thumb.getBounds();
      topBound = oldBounds.top;
      bottomBound = oldBounds.bottom;
    } else {
      topBound = gap;
      bottomBound = gap + thumbHeight;
    }
    thumb.setBounds(thumbPos, topBound, thumbPos + thumbWidth, bottomBound);
  }

  public void setThumb(Drawable thumb) {
    mThumb = thumb;
    super.setThumb(thumb);
  }

  void onStartTrackingTouch() {
    if (mOnSeekBarChangeListener != null) {
      mOnSeekBarChangeListener.onStartTrackingTouch(this);
    }
  }

  void onStopTrackingTouch() {
    if (mOnSeekBarChangeListener != null) {
      mOnSeekBarChangeListener.onStopTrackingTouch(this);
    }
  }

  private void attemptClaimDrag() {
    if (getParent() != null) {
      getParent().requestDisallowInterceptTouchEvent(true);
    }
  }

  @Override
  public boolean onTouchEvent(MotionEvent event) {
    if (!isEnabled()) {
      return false;
    }

    switch (event.getAction()) {
    case MotionEvent.ACTION_DOWN:
      setPressed(true);
      onStartTrackingTouch();
      break;

    case MotionEvent.ACTION_MOVE:
      attemptClaimDrag();
      setProgress(getMax() - (int) (getMax() * event.getY() / getHeight()));
      break;
    case MotionEvent.ACTION_UP:
      onStopTrackingTouch();
      setPressed(false);
      break;

    case MotionEvent.ACTION_CANCEL:
      onStopTrackingTouch();
      setPressed(false);
      break;
    }
    return true;
  }