/**
* 构造器1
* @param context
* @param listener
*/
public MultiTouchGestureDetector(Context context, MultiTouchGestureListener listener) {
this(context, listener, null);
} /**
* 构造器2
* @param context
* @param listener
* @param handler
*/
public MultiTouchGestureDetector(Context context, MultiTouchGestureListener listener, Handler handler) {
if (handler != null) {
mHandler = new GestureHandler(handler);
} else {
mHandler = new GestureHandler();
}
mListener = listener;
if (listener instanceof MultiTouchDoubleTapListener) {
setOnDoubleTapListener((MultiTouchDoubleTapListener) listener);
}
init(context);
} /**
* 初始化识别器
* @param context
*/
private void init(Context context) {
if (mListener == null) {
throw new NullPointerException("OnGestureListener must not be null");
}
mIsLongpressEnabled = true; int touchSlop, doubleTapSlop;
if (context == null) {
touchSlop = ViewConfiguration.getTouchSlop();
doubleTapSlop = DOUBLE_TAP_SLAP;
mMinimumFlingVelocity = ViewConfiguration.getMinimumFlingVelocity();
mMaximumFlingVelocity = ViewConfiguration.getMaximumFlingVelocity();
} else {//允许识别器在App中，使用偏好的设定
final ViewConfiguration configuration = ViewConfiguration.get(context);
touchSlop = configuration.getScaledTouchSlop();
doubleTapSlop = configuration.getScaledDoubleTapSlop();
mMinimumFlingVelocity = configuration.getScaledMinimumFlingVelocity();
mMaximumFlingVelocity = configuration.getScaledMaximumFlingVelocity();
}
mTouchSlopSquare = touchSlop * touchSlop / 16;
mDoubleTapSlopSquare = doubleTapSlop * doubleTapSlop;
} /**
* 设置双击监听器
* @param onDoubleTapListener
*/
public void setOnDoubleTapListener(MultiTouchDoubleTapListener onDoubleTapListener) {
mDoubleTapListener = onDoubleTapListener;
} /**
* 设置是否允许长按
* @param isLongpressEnabled
*/
public void setIsLongpressEnabled(boolean isLongpressEnabled) {
mIsLongpressEnabled = isLongpressEnabled;
} /**
* 判断是否允许长按
* @return
*/
public boolean isLongpressEnabled() {
return mIsLongpressEnabled;
} /**
* 判断当前事件是否为双击事件
* <br/> 通过遍历sEventForDoubleTap来匹配是否存在能够构成双击事件的单击事件
* @param e
* @return
*/
private EventInfo checkForDoubleTap(MultiMotionEvent e) {
if (sEventForDoubleTap.isEmpty()) {
// Log.e(MYTAG, CLASS_NAME + ":checkForDoubleTap(), sEventForDoubleTap is empty !");
return null;
}
for (int i = 0; i < sEventForDoubleTap.size(); i++) {
EventInfo info = sEventForDoubleTap.get(i);
if (info != null && isConsideredDoubleTap(info, e)) {
sEventForDoubleTap.set(i, null);// 这个单击事件已经被消耗了，所以置为null
mHandler.removeMessages(TAP_DOUBLE, i);// 移除Handler内的为处理消息
return info;
}
}
return null;
} /**
* 判断当前按下事件是否能和指定的单击事件构成双击事件
*
* @param info
* @param secondDown
* @return
*/
private boolean isConsideredDoubleTap(EventInfo info, MultiMotionEvent secondDown) {
if (!info.mAlwaysInBiggerTapRegion) { //如多第一次单击事件有过较大距离的移动，则无法构成双击事件
return false;
}
if (secondDown.getEventTime() - info.mPreviousUpEvent.getEventTime() > DOUBLE_TAP_TIMEOUT) {
//如果第一次单击的UP时间和第二次单击的down时间时间间隔大于DOUBLE_TAP_TIMEOUT，也无法构成双击事件
return false;
}
int deltaX = (int) info.mCurrentDownEvent.getX() - (int) secondDown.getX();
int deltaY = (int) info.mCurrentDownEvent.getY() - (int) secondDown.getY();
return (deltaX * deltaX + deltaY * deltaY < mDoubleTapSlopSquare);//最后判断两次单击事件的距离
} /**
* 将事件信息放入双击判断队列，并返回序号
*
* @param info
* @return
*/
private int addIntoTheMinIndex(EventInfo info) {
for (int i = 0; i < sEventForDoubleTap.size(); i++) {
if (sEventForDoubleTap.get(i) == null) {
sEventForDoubleTap.set(i, info);
return i;
}
}
sEventForDoubleTap.add(info);
return sEventForDoubleTap.size() - 1;
} /**
* 从事件信息队列中移除指定序号的事件
*
* @param idx
*/
private void removeEventFromList(int id) {
if (id > sEventInfos.size() || id < 0) {
// Log.e(MYTAG, CLASS_NAME + ".removeEventFromList(), id=" + id + ", while sEventInfos.size() =" + sEventInfos.size());
return;
}
sEventInfos.set(id, null);
} /**
* 向事件队列中添加新信息
*
* @param e
*/
private void addEventIntoList(EventInfo info) {
int id = info.mCurrentDownEvent.getId();
if (id < sEventInfos.size()) {
// if (sEventInfos.get(id) != null)
// Log.e(MYTAG, CLASS_NAME + ".addEventIntoList, info(" + id + ") has not set to null !");
sEventInfos.set(info.mCurrentDownEvent.getId(), info);
} else if (id == sEventInfos.size()) {
sEventInfos.add(info);
} else {
// Log.e(MYTAG, CLASS_NAME + ".addEventIntoList, invalidata id !");
}
}
* 构造器1
* @param context
* @param listener
*/
public MultiTouchGestureDetector(Context context, MultiTouchGestureListener listener) {
this(context, listener, null);
} /**
* 构造器2
* @param context
* @param listener
* @param handler
*/
public MultiTouchGestureDetector(Context context, MultiTouchGestureListener listener, Handler handler) {
if (handler != null) {
mHandler = new GestureHandler(handler);
} else {
mHandler = new GestureHandler();
}
mListener = listener;
if (listener instanceof MultiTouchDoubleTapListener) {
setOnDoubleTapListener((MultiTouchDoubleTapListener) listener);
}
init(context);
} /**
* 初始化识别器
* @param context
*/
private void init(Context context) {
if (mListener == null) {
throw new NullPointerException("OnGestureListener must not be null");
}
mIsLongpressEnabled = true; int touchSlop, doubleTapSlop;
if (context == null) {
touchSlop = ViewConfiguration.getTouchSlop();
doubleTapSlop = DOUBLE_TAP_SLAP;
mMinimumFlingVelocity = ViewConfiguration.getMinimumFlingVelocity();
mMaximumFlingVelocity = ViewConfiguration.getMaximumFlingVelocity();
} else {//允许识别器在App中，使用偏好的设定
final ViewConfiguration configuration = ViewConfiguration.get(context);
touchSlop = configuration.getScaledTouchSlop();
doubleTapSlop = configuration.getScaledDoubleTapSlop();
mMinimumFlingVelocity = configuration.getScaledMinimumFlingVelocity();
mMaximumFlingVelocity = configuration.getScaledMaximumFlingVelocity();
}
mTouchSlopSquare = touchSlop * touchSlop / 16;
mDoubleTapSlopSquare = doubleTapSlop * doubleTapSlop;
} /**
* 设置双击监听器
* @param onDoubleTapListener
*/
public void setOnDoubleTapListener(MultiTouchDoubleTapListener onDoubleTapListener) {
mDoubleTapListener = onDoubleTapListener;
} /**
* 设置是否允许长按
* @param isLongpressEnabled
*/
public void setIsLongpressEnabled(boolean isLongpressEnabled) {
mIsLongpressEnabled = isLongpressEnabled;
} /**
* 判断是否允许长按
* @return
*/
public boolean isLongpressEnabled() {
return mIsLongpressEnabled;
} /**
* 判断当前事件是否为双击事件
* <br/> 通过遍历sEventForDoubleTap来匹配是否存在能够构成双击事件的单击事件
* @param e
* @return
*/
private EventInfo checkForDoubleTap(MultiMotionEvent e) {
if (sEventForDoubleTap.isEmpty()) {
// Log.e(MYTAG, CLASS_NAME + ":checkForDoubleTap(), sEventForDoubleTap is empty !");
return null;
}
for (int i = 0; i < sEventForDoubleTap.size(); i++) {
EventInfo info = sEventForDoubleTap.get(i);
if (info != null && isConsideredDoubleTap(info, e)) {
sEventForDoubleTap.set(i, null);// 这个单击事件已经被消耗了，所以置为null
mHandler.removeMessages(TAP_DOUBLE, i);// 移除Handler内的为处理消息
return info;
}
}
return null;
} /**
* 判断当前按下事件是否能和指定的单击事件构成双击事件
*
* @param info
* @param secondDown
* @return
*/
private boolean isConsideredDoubleTap(EventInfo info, MultiMotionEvent secondDown) {
if (!info.mAlwaysInBiggerTapRegion) { //如多第一次单击事件有过较大距离的移动，则无法构成双击事件
return false;
}
if (secondDown.getEventTime() - info.mPreviousUpEvent.getEventTime() > DOUBLE_TAP_TIMEOUT) {
//如果第一次单击的UP时间和第二次单击的down时间时间间隔大于DOUBLE_TAP_TIMEOUT，也无法构成双击事件
return false;
}
int deltaX = (int) info.mCurrentDownEvent.getX() - (int) secondDown.getX();
int deltaY = (int) info.mCurrentDownEvent.getY() - (int) secondDown.getY();
return (deltaX * deltaX + deltaY * deltaY < mDoubleTapSlopSquare);//最后判断两次单击事件的距离
} /**
* 将事件信息放入双击判断队列，并返回序号
*
* @param info
* @return
*/
private int addIntoTheMinIndex(EventInfo info) {
for (int i = 0; i < sEventForDoubleTap.size(); i++) {
if (sEventForDoubleTap.get(i) == null) {
sEventForDoubleTap.set(i, info);
return i;
}
}
sEventForDoubleTap.add(info);
return sEventForDoubleTap.size() - 1;
} /**
* 从事件信息队列中移除指定序号的事件
*
* @param idx
*/
private void removeEventFromList(int id) {
if (id > sEventInfos.size() || id < 0) {
// Log.e(MYTAG, CLASS_NAME + ".removeEventFromList(), id=" + id + ", while sEventInfos.size() =" + sEventInfos.size());
return;
}
sEventInfos.set(id, null);
} /**
* 向事件队列中添加新信息
*
* @param e
*/
private void addEventIntoList(EventInfo info) {
int id = info.mCurrentDownEvent.getId();
if (id < sEventInfos.size()) {
// if (sEventInfos.get(id) != null)
// Log.e(MYTAG, CLASS_NAME + ".addEventIntoList, info(" + id + ") has not set to null !");
sEventInfos.set(info.mCurrentDownEvent.getId(), info);
} else if (id == sEventInfos.size()) {
sEventInfos.add(info);
} else {
// Log.e(MYTAG, CLASS_NAME + ".addEventIntoList, invalidata id !");
}
}
if (mVelocityTracker == null) {
mVelocityTracker = VelocityTracker.obtain();
}
mVelocityTracker.addMovement(ev);//把所有事件都添加到速度追踪器，为计算速度做准备 boolean handled = false;
final int action = ev.getAction(); //获取Action
// int idx = (action & MotionEvent.ACTION_POINTER_INDEX_MASK) >> MotionEvent.ACTION_POINTER_INDEX_SHIFT;//获取触摸事件的序号
int idx = ev.getPointerId(ev.getActionIndex());//获取触摸事件的id switch (action & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
case MotionEvent.ACTION_POINTER_DOWN: {
EventInfo info = new EventInfo(MotionEvent.obtain(ev));
this.addEventIntoList(info);//将手势信息保存到队列中
if (mDoubleTapListener != null) {//如果双击监听器不为null
if (mHandler.hasMessages(TAP_DOUBLE)) {
MultiMotionEvent e = new MultiMotionEvent(ev);
EventInfo origInfo = checkForDoubleTap(e);//检查是否构成双击事件
if (origInfo != null) {
info.mIsDoubleTapping = true;
handled |= mDoubleTapListener.onDoubleTap(origInfo.mCurrentDownEvent);
handled |= mDoubleTapListener.onDoubleTapEvent(e);
}
}
if (!info.mIsDoubleTapping) {//当前事件不构成双击事件，那么发送延迟消息以判断onSingleTapConfirmed事件
mHandler.sendMessageDelayed(mHandler.obtainMessage(TAP_SINGLE, idx), DOUBLE_TAP_TIMEOUT);
// Log.d(MYTAG, CLASS_NAME + ": add TAP_SINGLE");
}
}
// 记录X坐标和Y坐标
info.mLastMotionX = info.mCurrentDownEvent.getX();
info.mLastMotionY = info.mCurrentDownEvent.getY();
if (mIsLongpressEnabled) {//允许长按
mHandler.removeMessages(LONG_PRESS, idx);
mHandler.sendMessageAtTime(mHandler.obtainMessage(LONG_PRESS, idx), info.mCurrentDownEvent.getEventTime() + TAP_TIMEOUT
+ LONGPRESS_TIMEOUT);//延时消息以触发长按手势
// Log.d(MYTAG, CLASS_NAME +
// ":add LONG_PRESS to handler for idx " + idx);
} mHandler.sendMessageAtTime(mHandler.obtainMessage(SHOW_PRESS, idx), info.mCurrentDownEvent.getEventTime() + TAP_TIMEOUT);// 延时消息，触发showPress手势
handled |= mListener.onDown(info.mCurrentDownEvent);//触发onDown（）
break;
}
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_POINTER_UP: {
MultiMotionEvent currentUpEvent = new MultiMotionEvent(ev);
if (idx >= sEventInfos.size()) {
// Log.e(MYTAG, CLASS_NAME + ":ACTION_POINTER_UP, idx=" + idx + ", while sEventInfos.size()=" + sEventInfos.size());
break;
}
EventInfo info = sEventInfos.get(currentUpEvent.getId());
if (info == null) {
// Log.e(MYTAG, CLASS_NAME + ":ACTION_POINTER_UP, idx=" + idx + ", Info = null");
break;
} info.mStillDown = false;
if (info.mIsDoubleTapping) { //处于双击状态，则触发onDoubleTapEvent事件
handled |= mDoubleTapListener.onDoubleTapEvent(currentUpEvent);
} else if (info.mInLongPress) {//处于长按状态
mHandler.removeMessages(TAP_SINGLE, idx);//可以无视这行代码
info.mInLongPress = false;
} else if (info.mAlwaysInTapRegion) {//尚未移动过
if (mHandler.hasMessages(TAP_SINGLE, idx)) {//还在双击的时间阀值内，所以要为双击判断做额外处理
mHandler.removeMessages(TAP_SINGLE, idx);
info.mPreviousUpEvent = new MultiMotionEvent(MotionEvent.obtain(ev));
int index = this.addIntoTheMinIndex(info);// 把当前事件放入队列，等待双击的判断
mHandler.sendMessageAtTime(mHandler.obtainMessage(TAP_DOUBLE, index), info.mCurrentDownEvent.getEventTime()
+ DOUBLE_TAP_TIMEOUT); // 将双击超时判断添加到Handler
// Log.d(MYTAG, CLASS_NAME + ": add TAP_DOUBLE");
}
handled = mListener.onSingleTapUp(currentUpEvent);//触发onSingleTapUp事件
} else {
// A fling must travel the minimum tap distance
final VelocityTracker velocityTracker = mVelocityTracker;
velocityTracker.computeCurrentVelocity(1000, mMaximumFlingVelocity);//计算1秒钟内的滑动速度
//获取X和Y方向的速度
final float velocityX = velocityTracker.getXVelocity(idx);
final float velocityY = velocityTracker.getYVelocity(idx); // Log.i(MYTAG, CLASS_NAME + ":ACTION_POINTER_UP, idx=" + idx +
// ", vx=" + velocityX + ", vy=" + velocityY);
// 触发滑动事件
if ((Math.abs(velocityY) > mMinimumFlingVelocity) || (Math.abs(velocityX) > mMinimumFlingVelocity)) {
handled = mListener.onFling(info.mCurrentDownEvent, currentUpEvent, velocityX, velocityY);
}
}
// Hold the event we obtained above - listeners may have changed the
// original.
if (action == MotionEvent.ACTION_UP) { //释放速度追踪器
mVelocityTracker.recycle();
mVelocityTracker = null;
// Log.w(MYTAG, CLASS_NAME +
// ":ACTION_POINTER_UP, mVelocityTracker.recycle()");
}
info.mIsDoubleTapping = false;
// Log.d(MYTAG, CLASS_NAME + "remove LONG_PRESS");
// 移除showPress和长按消息
mHandler.removeMessages(SHOW_PRESS, idx);
mHandler.removeMessages(LONG_PRESS, idx); removeEventFromList(currentUpEvent.getId());//手指离开，则从队列中删除手势信息
break;
} case MotionEvent.ACTION_MOVE:
for (int rIdx = 0; rIdx < ev.getPointerCount(); rIdx++) {//因为无法确定当前发生移动的是哪个手指，所以遍历处理所有手指
MultiMotionEvent e = new MultiMotionEvent(ev, rIdx);
if (e.getId() >= sEventInfos.size()) {
// Log.e(MYTAG, CLASS_NAME + ":ACTION_MOVE, idx=" + rIdx + ", while sEventInfos.size()=" + sEventInfos.size());
break;
}
EventInfo info = sEventInfos.get(e.getId());
if (info == null) {
// Log.e(MYTAG, CLASS_NAME + ":ACTION_MOVE, idx=" + rIdx + ", Info = null");
break;
}
if (info.mInLongPress) { //长按，则不处理move事件
break;
}
//当前坐标
float x = e.getX();
float y = e.getY();
//距离上次事件移动的位置
final float scrollX = x - info.mLastMotionX;
final float scrollY = y - info.mLastMotionY;
if (info.mIsDoubleTapping) {//双击事件
handled |= mDoubleTapListener.onDoubleTapEvent(e);
} else if (info.mAlwaysInTapRegion) {//该手势尚未移动过（移动的距离小于mTouchSlopSquare,视为未移动过）
// 计算从落下到当前事件，移动的距离
final int deltaX = (int) (x - info.mCurrentDownEvent.getX());
final int deltaY = (int) (y - info.mCurrentDownEvent.getY());
// Log.d(MYTAG, CLASS_NAME + "deltaX="+deltaX+";deltaY=" +
// deltaX +"mTouchSlopSquare=" + mTouchSlopSquare);
int distance = (deltaX * deltaX) + (deltaY * deltaY);
if (distance > mTouchSlopSquare) { // 移动距离超过mTouchSlopSquare
handled = mListener.onScroll(info.mCurrentDownEvent, e, scrollX, scrollY);
info.mLastMotionX = e.getX();
info.mLastMotionY = e.getY();
info.mAlwaysInTapRegion = false;
// Log.d(MYTAG, CLASS_NAME +
// ":remove LONG_PRESS for idx" + rIdx +
// ",mTouchSlopSquare("+mTouchSlopSquare+"), distance("+distance+")");
// 清除onSingleTapConform，showPress,longPress三种消息
int id = e.getId();
mHandler.removeMessages(TAP_SINGLE, id);
mHandler.removeMessages(SHOW_PRESS, id);
mHandler.removeMessages(LONG_PRESS, id);
}
if (distance > mBiggerTouchSlopSquare) {//移动距离大于mBiggerTouchSlopSquare，则无法构成双击事件
info.mAlwaysInBiggerTapRegion = false;
}
} else if ((Math.abs(scrollX) >= 1) || (Math.abs(scrollY) >= 1)) {//之前已经移动过了
handled = mListener.onScroll(info.mCurrentDownEvent, e, scrollX, scrollY);
info.mLastMotionX = x;
info.mLastMotionY = y;
}
}
break;
case MotionEvent.ACTION_CANCEL:
cancel();//清理
}
return handled;
} // 清理所有队列
private void cancel() {
mHandler.removeMessages(SHOW_PRESS);
mHandler.removeMessages(LONG_PRESS);
mHandler.removeMessages(TAP_SINGLE);
mVelocityTracker.recycle();
mVelocityTracker = null;
sEventInfos.clear();
sEventForDoubleTap.clear();
}
} 最后在这里小小的挂个广告：
我和朋友们写的App在这里，希望给个支持：
电子市场链接地址
Youtube演示视频1（请翻墙）
Youtube演示视频2（请翻墙）
谢谢指教，以后个人的小App里，会尝试使用的