Android实现垂直进度条VerticalSeekBar

本文实例为大家分享了Android实现垂直进度条的具体代码，供大家参考，具体内容如下

成都创新互联基于分布式IDC数据中心构建的平台为众多户提供服务器托管四川大带宽租用成都机柜租用成都服务器租用。

水平的进度条见多了，总会想见个垂直的进度条开开眼。今天咱就试试。
要说原理也简单，就是把宽高倒置，其他的理论上都不需要动，发现问题再补补也就行了。

官方提供

官方是提供了垂直进度条的例子源码的，位置在android-sdk-windows\sources\android-23\com\android\example\rscamera\VerticalSeekBar.java，当然首先你SDK中要有Android 6.0。

VerticalSeekBar.java

/**
 * 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;
  }
}

继承SeekBar是最简单快捷的，不用重写太多方法，只需要把

onMeasure
onSizeChanged
onDraw

三个方法作一些改动；但也有一些问题，比如只能响应onPregress方法，为了让他能响应onStartTrackingTouch和onStopTrackingTouch方法，只好再加一些代码，于是有了改进版。

稍作改进

VerticalSeekBar2.java

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;
  }

为了响应另外两个不知道怎么就被onPregress抛弃的方法，添了这么多代码真是罪过，不过都是从SeekBar的父类AbsSeekBar中仿写过来的，逻辑稍作改动就能用。

对比测试

上图。

Android实现垂直进度条VerticalSeekBar

左边是官方例子中的，右边是改进过的。

测试源码：垂直进度条VerticalSeekBar

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持创新互联。

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