本文實例為大家分享了Android實現垂直進度條的具體代碼，供大家參考，具體內容如下
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，發現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onPregress方法，為了讓他能響應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。
左邊是官方例子中的，右邊是改進過的。
測試源碼：垂直進度條VerticalSeekBar
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持億速云。
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