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Android實現(xiàn)垂直進度條VerticalSeekBar

更新時間：2021年01月27日 11:55:49 作者：秦漢春秋

這篇文章主要為大家詳細介紹了Android實現(xiàn)垂直進度條VerticalSeekBar的相關(guān)資料，具有一定的參考價值，感興趣的小伙伴們可以參考一下

本文實例為大家分享了Android實現(xiàn)垂直進度條的具體代碼，供大家參考，具體內(nèi)容如下

水平的進度條見多了，總會想見個垂直的進度條開開眼。今天咱就試試。
要說原理也簡單，就是把寬高倒置，其他的理論上都不需要動，發(fā)現(xiàn)問題再補補也就行了。

官方提供

官方是提供了垂直進度條的例子源碼的，位置在android-sdk-windows\sources\android-23\com\android\example\rscamera\VerticalSeekBar.java，當(dāng)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;
 }
}

繼承SeekBar是最簡單快捷的，不用重寫太多方法，只需要把

onMeasure
onSizeChanged
onDraw

三個方法作一些改動；但也有一些問題，比如只能響應(yīng)onPregress方法，為了讓他能響應(yīng)onStartTrackingTouch和onStopTrackingTouch方法，只好再加一些代碼，于是有了改進版。

稍作改進

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;
 }

為了響應(yīng)另外兩個不知道怎么就被onPregress拋棄的方法，添了這么多代碼真是罪過，不過都是從SeekBar的父類AbsSeekBar中仿寫過來的，邏輯稍作改動就能用。

對比測試

上圖。