Example usage for android.view VelocityTracker obtain

List of usage examples for android.view VelocityTracker obtain

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Introduction

In this page you can find the example usage for android.view VelocityTracker obtain.

Prototype

static public VelocityTracker obtain()

Source Link

Document

Retrieve a new VelocityTracker object to watch the velocity of a motion.

Usage

From source file:ngoctdn.vng.gesture.CupcakeGestureDetector.java

public boolean onTouchEvent(MotionEvent ev) {
    switch (ev.getAction()) {
    case MotionEvent.ACTION_DOWN: {
        mVelocityTracker = VelocityTracker.obtain();
        if (null != mVelocityTracker) {
            mVelocityTracker.addMovement(ev);
        } else {//from ww w.j ava2s .  c o  m
            Log.i(LOG_TAG, "Velocity tracker is null");
        }

        mLastTouchX = getActiveX(ev);
        mLastTouchY = getActiveY(ev);
        mFirstRawTouchY = ev.getRawY();
        mLastRawTouchY = ev.getRawY();
        mIsDragging = false;
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        break;
    }

    case MotionEvent.ACTION_POINTER_DOWN:
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        break;

    case MotionEvent.ACTION_MOVE: {
        final float x = getActiveX(ev);
        final float y = getActiveY(ev);
        final float dx = x - mLastTouchX, dy = y - mLastTouchY;

        if (!mIsDragging) {
            // Use Pythagoras to see if drag length is larger than
            // touch slop
            mIsDragging = Math.sqrt((dx * dx) + (dy * dy)) >= mTouchSlop;
        }

        if (mIsDragging) {
            if (ev.getPointerCount() == 1)
                mListener.onDrag(mLastRawTouchY, ev.getRawY(), dx, dy);
            mLastTouchX = x;
            mLastTouchY = y;
            mLastRawTouchY = ev.getRawY();
            // if (mListener != null) {
            // mListener.onScrolling(mLastRawTouchY, ev.getRawY());
            // mLastRawTouchY = ev.getRawY();
            // }

            if (null != mVelocityTracker) {
                mVelocityTracker.addMovement(ev);
            }
        }
        if (mActivePointerId == -1 && mListener != null) {
            mListener.onRelease(mFirstRawTouchY, ev.getRawY(), 0);
        }
        break;
    }

    case MotionEvent.ACTION_POINTER_UP:
    case MotionEvent.ACTION_CANCEL:
    case MotionEvent.ACTION_UP: {

        if (mIsDragging) {
            if (null != mVelocityTracker) {

                mLastTouchX = getActiveX(ev);
                mLastTouchY = getActiveY(ev);

                // if (mListener != null) {
                // mListener.onScrolling(mFirstTouchY, mLastTouchY);
                // }

                // Compute velocity within the last 1000ms
                mVelocityTracker.addMovement(ev);
                mVelocityTracker.computeCurrentVelocity(1000);

                final float vX = mVelocityTracker.getXVelocity(), vY = mVelocityTracker.getYVelocity();

                // If the velocity is greater than minVelocity, call
                // listener
                if (Math.max(Math.abs(vX), Math.abs(vY)) >= mMinimumVelocity) {
                    mListener.onFling(mLastTouchX, mLastTouchY, -vX, -vY);
                }
            }
        }

        if (mListener != null) {
            mLastRawTouchY = ev.getRawY();
            if (mVelocityTracker != null)
                mListener.onRelease(mFirstRawTouchY, ev.getRawY(), mVelocityTracker.getYVelocity());
            else
                mListener.onRelease(mFirstRawTouchY, ev.getRawY(), 0);
        }

        // Recycle Velocity Tracker
        if (null != mVelocityTracker) {
            mVelocityTracker.recycle();
            mVelocityTracker = null;
        }
        break;
    }
    }

    return true;
}

From source file:ngoctdn.vng.gesture.DragGestureDetector.java

public boolean onTouchEvent(MotionEvent ev) {
    switch (ev.getAction()) {
    case MotionEvent.ACTION_DOWN: {
        mVelocityTracker = VelocityTracker.obtain();
        if (null != mVelocityTracker) {
            mVelocityTracker.addMovement(ev);
        } else {//ww w.j  a  v  a 2 s.  com
            Log.i(LOG_TAG, "Velocity tracker is null");
        }

        mLastTouchX = getActiveX(ev);
        mLastTouchY = getActiveY(ev);
        mFirstRawTouchY = ev.getRawY();
        mLastRawTouchY = ev.getRawY();
        mIsDragging = false;
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        break;
    }

    case MotionEvent.ACTION_POINTER_DOWN:
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        break;

    case MotionEvent.ACTION_MOVE: {
        final float x = getActiveX(ev);
        final float y = getActiveY(ev);
        final float dx = x - mLastTouchX, dy = y - mLastTouchY;

        if (!mIsDragging) {
            // Use Pythagoras to see if drag length is larger than
            // touch slop
            mIsDragging = (float) Math.sqrt((dx * dx) + (dy * dy)) >= mTouchSlop;
        }

        if (mIsDragging) {
            if (ev.getPointerCount() == 1)
                mListener.onDrag(mLastRawTouchY, ev.getRawY(), dx, dy);
            mLastTouchX = x;
            mLastTouchY = y;
            mLastRawTouchY = ev.getRawY();
            // if (mListener != null) {
            // mListener.onScrolling(mLastRawTouchY, ev.getRawY());
            // mLastRawTouchY = ev.getRawY();
            // }

            if (null != mVelocityTracker) {
                mVelocityTracker.addMovement(ev);
            }
        }
        if (mActivePointerId == -1 && mListener != null) {
            mListener.onRelease(mFirstRawTouchY, ev.getRawY(), 0);
        }
        break;
    }

    //      case MotionEvent.ACTION_CANCEL: {
    //         if (mListener != null) {
    //            mLastRawTouchY = ev.getRawY();
    //            mListener.onRelease(mFirstRawTouchY, ev.getRawY());
    //         }
    //         // Recycle Velocity Tracker
    //         if (null != mVelocityTracker) {
    //            mVelocityTracker.recycle();
    //            mVelocityTracker = null;
    //         }
    //         break;
    //      }
    case MotionEvent.ACTION_POINTER_UP:
    case MotionEvent.ACTION_CANCEL:
    case MotionEvent.ACTION_UP: {

        if (mIsDragging) {
            if (null != mVelocityTracker) {

                mLastTouchX = getActiveX(ev);
                mLastTouchY = getActiveY(ev);

                // if (mListener != null) {
                // mListener.onScrolling(mFirstTouchY, mLastTouchY);
                // }

                // Compute velocity within the last 1000ms
                mVelocityTracker.addMovement(ev);
                mVelocityTracker.computeCurrentVelocity(1000);

                final float vX = mVelocityTracker.getXVelocity(), vY = mVelocityTracker.getYVelocity();

                // If the velocity is greater than minVelocity, call
                // listener
                if (Math.max(Math.abs(vX), Math.abs(vY)) >= mMinimumVelocity) {
                    mListener.onFling(mLastTouchX, mLastTouchY, -vX, -vY);
                }
            }
        }

        if (mListener != null) {
            mLastRawTouchY = ev.getRawY();
            if (mVelocityTracker != null)
                mListener.onRelease(mFirstRawTouchY, ev.getRawY(), mVelocityTracker.getYVelocity());
            else
                mListener.onRelease(mFirstRawTouchY, ev.getRawY(), 0);
        }

        // Recycle Velocity Tracker
        if (null != mVelocityTracker) {
            mVelocityTracker.recycle();
            mVelocityTracker = null;
        }
        break;
    }
    }

    return true;
}

From source file:co.adrianblan.fastbrush.MyGLSurfaceView.java

@Override
public boolean onTouchEvent(MotionEvent e) {
    // MotionEvent reports input details from the touch screen
    // and other input controls. In this case, you are only
    // interested in events where the touch position changed.

    switch (e.getAction()) {

    case MotionEvent.ACTION_DOWN:
        if (mVelocityTracker == null) {
            mVelocityTracker = VelocityTracker.obtain();
        } else {/*from  ww  w  .  j a  v  a  2 s.co m*/
            mVelocityTracker.clear();
        }

        queueEvent(new Runnable() {
            @Override
            public void run() {
                mRenderer.touchHasStarted();
            }
        });

        // No break is intentional

    case MotionEvent.ACTION_MOVE:

        mVelocityTracker.addMovement(e);

        // Compute velocity in pixels per second
        mVelocityTracker.computeCurrentVelocity(1);

        final ArrayList<TouchData> touchDataList = new ArrayList<>(e.getHistorySize() + 1);
        Vector2 viewportPosition;

        Vector2 viewportVelocity = new Vector2(
                VelocityTrackerCompat.getXVelocity(mVelocityTracker, e.getActionIndex()),
                VelocityTrackerCompat.getYVelocity(mVelocityTracker, e.getActionIndex()));

        // Add previous touch coordinates
        for (int i = 0; i < e.getHistorySize(); i++) {
            viewportPosition = new Vector2(e.getHistoricalX(i), e.getHistoricalY(i));

            touchDataList.add(new TouchData(mRenderer.viewportToWorld(viewportPosition), viewportVelocity,
                    e.getHistoricalSize(i), e.getHistoricalPressure(i)));
        }

        // Add current touch coordinates
        viewportPosition = new Vector2(e.getX(), e.getY());
        touchDataList.add(new TouchData(mRenderer.viewportToWorld(viewportPosition), viewportVelocity,
                e.getSize(), e.getPressure()));

        // Ensure we call switchMode() on the OpenGL thread.
        // queueEvent() is a method of GLSurfaceView that will do this for us.
        queueEvent(new Runnable() {
            @Override
            public void run() {
                mRenderer.addTouchData(touchDataList);
            }
        });

        requestRender();
        break;

    case MotionEvent.ACTION_UP:

        queueEvent(new Runnable() {
            @Override
            public void run() {
                mRenderer.touchHasEnded();
            }
        });
        requestRender();
        break;
    }
    return true;
}

From source file:com.focosee.qingshow.widget.MVerticalViewPager.java

public boolean onTouchEvent(MotionEvent event) {
    super.onTouchEvent(event);

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }/* w ww .  java  2 s  .  c  o  m*/
    mVelocityTracker.addMovement(event);

    float currentY = event.getRawY();
    switch (event.getAction() & MotionEventCompat.ACTION_MASK) {
    case MotionEvent.ACTION_DOWN:
        mLastY = currentY;
        mMoved = false;
        break;
    case MotionEvent.ACTION_MOVE:
        mMoved = true;
        break;
    case MotionEvent.ACTION_UP:
        if (mMoved) {
            mVelocityTracker.computeCurrentVelocity(1000);
            int velocity = (int) mVelocityTracker.getYVelocity();
            float moveDistance = currentY - mLastY;
            int nextPage = mCurrentPage;
            if (moveDistance < 0 && Math.abs(moveDistance) >= SCROLL_PERCENTAGE * mSinglePageHeight
                    || velocity < 0 && Math.abs(velocity) > MIN_FLING_VELOCITY) {
                ++nextPage;
            } else if (moveDistance > 0 && Math.abs(moveDistance) >= SCROLL_PERCENTAGE * mSinglePageHeight
                    || velocity > 0 && Math.abs(velocity) > MIN_FLING_VELOCITY) {
                --nextPage;
            }
            setCurrentItem(nextPage);
        }
        break;
    }
    return true;
}

From source file:com.github.shareme.gwsmaterialuikit.library.ccv.CompactCalendarView.java

public CompactCalendarView(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
    compactCalendarController = new CompactCalendarController(new Paint(), new OverScroller(getContext()),
            new Rect(), attrs, getContext(), Color.argb(255, 233, 84, 81), Color.argb(255, 64, 64, 64),
            Color.argb(255, 219, 219, 219), VelocityTracker.obtain());
    gestureDetector = new GestureDetectorCompat(getContext(), gestureListener);
    animationHandler = new AnimationHandler(compactCalendarController, this);
}

From source file:com.appsimobile.appsii.SidebarHotspot.java

@Override
public boolean onTouchEvent(MotionEvent e) {
    switch (e.getAction()) {
    case MotionEvent.ACTION_DOWN: {
        mVelocityTracker = VelocityTracker.obtain();
        mVelocityTracker.addMovement(e);
        // remove the background to make sure it does not overlap
        // the sidebar

        mIsDragOpening = true;/*from w  ww.ja  v a 2 s  . c o  m*/
        setBackgroundResource(0);

        float x = e.getX();
        float y = e.getY();

        if (mCallback != null) {
            mSwipeListener = mCallback.open(this, Gesture.TO_CENTER, (int) x, (int) y);
            mSwipeInProgress = mSwipeListener != null;
            mState = STATE_AWAITING_RELEASE;
            if (mVibrate) {
                vibrate();
            }

            return true;
        }
        return false;
    }
    case MotionEvent.ACTION_MOVE:
        mVelocityTracker.addMovement(e);
        float x = e.getX();
        float y = e.getY();
        return detectSwipe(x, y, e);
    case MotionEvent.ACTION_UP:
    case MotionEvent.ACTION_CANCEL:
        cancelMotionHandling(e, false);
        return false;
    }

    return super.onTouchEvent(e);
}

From source file:com.tjych.swip.vertical_t.VerticalViewPager.java

public boolean onTouchEvent(MotionEvent event) {
    super.onTouchEvent(event);

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }/*from ww  w  . j a va  2s  . c o m*/
    mVelocityTracker.addMovement(event);

    float currentY = event.getRawY();
    float currentX = event.getRawX();
    switch (event.getAction() & MotionEventCompat.ACTION_MASK) {
    case MotionEvent.ACTION_DOWN:
        mLastY = currentY;
        mLastX = currentX;
        mMoved = false;
        return false;
    case MotionEvent.ACTION_MOVE:
        float x = event.getRawX() - mLastX;
        float y = event.getRawY() - mLastY;

        System.out.println(x + " : " + y);

        if (Math.abs(x) > Math.abs(y)) {
            // getParent().requestDisallowInterceptTouchEvent(true);
            return false;
        } else {
            mMoved = true;
            return true;
        }

    case MotionEvent.ACTION_UP:
        x = event.getRawX() - mLastX;
        y = event.getRawY() - mLastY;
        System.out.println(x + " : " + y);
        if (Math.abs(x) > Math.abs(y)) {
            // getParent().requestDisallowInterceptTouchEvent(true);
            return false;
        }
        if (mMoved) {
            mVelocityTracker.computeCurrentVelocity(1000);
            int velocity = (int) mVelocityTracker.getYVelocity();
            float moveDistance = currentY - mLastY;
            int nextPage = mCurrentPage;
            if (moveDistance < 0 && Math.abs(moveDistance) >= SCROLL_PERCENTAGE * mSinglePageHeight
                    || velocity < 0 && Math.abs(velocity) > MIN_FLING_VELOCITY) {
                ++nextPage;
            } else if (moveDistance > 0 && Math.abs(moveDistance) >= SCROLL_PERCENTAGE * mSinglePageHeight
                    || velocity > 0 && Math.abs(velocity) > MIN_FLING_VELOCITY) {
                --nextPage;
            }
            setCurrentItem(nextPage);
        }
        return true;
    }
    return true;
}

From source file:com.itude.mobile.mobbl.blueprint.app.view.listeners.SwipeDismissRecyclerViewTouchListener.java

@Override
public boolean onTouch(View view, MotionEvent motionEvent) {

    if (mViewWidth < 2) {
        mViewWidth = mIsVertical ? mRecyclerView.getHeight() : mRecyclerView.getWidth();
    }// ww  w  .j  a v  a2  s .c om

    switch (motionEvent.getActionMasked()) {
    case MotionEvent.ACTION_DOWN: {
        if (mPaused) {
            return false;
        }

        // TODO: ensure this is a finger, and set a flag

        // Find the child view that was touched (perform a hit test)
        Rect rect = new Rect();
        int childCount = mRecyclerView.getChildCount();
        int[] listViewCoords = new int[2];
        mRecyclerView.getLocationOnScreen(listViewCoords);
        int x = (int) motionEvent.getRawX() - listViewCoords[0];
        int y = (int) motionEvent.getRawY() - listViewCoords[1];
        View child;

        mDownView = mRecyclerView.findChildViewUnder(x, y);

        if (mDownView != null) {
            mDownX = motionEvent.getRawX();
            mDownY = motionEvent.getRawY();

            mDownPosition = mRecyclerView.getChildPosition(mDownView);
            if (mCallbacks.canDismiss(mDownPosition)) {
                mVelocityTracker = VelocityTracker.obtain();
                mVelocityTracker.addMovement(motionEvent);
            } else {
                mDownView = null;
            }
        }
        return false;
    }

    case MotionEvent.ACTION_CANCEL: {
        if (mVelocityTracker == null) {
            break;
        }

        if (mDownView != null && mSwiping) {
            // cancel
            if (mIsVertical) {
                mDownView.animate().translationY(0).alpha(1).setDuration(mAnimationTime).setListener(null);
            } else {
                mDownView.animate().translationX(0).alpha(1).setDuration(mAnimationTime).setListener(null);
            }
        }
        mVelocityTracker.recycle();
        mVelocityTracker = null;
        mDownX = 0;
        mDownY = 0;
        mDownView = null;
        mDownPosition = RecyclerView.NO_POSITION;
        mSwiping = false;
        break;
    }

    case MotionEvent.ACTION_UP: {
        if (!mSwiping && mDownView != null && mItemTouchCallback != null) {

            mItemTouchCallback.onTouch(mRecyclerView.getChildPosition(mDownView));
            mVelocityTracker.recycle();
            mVelocityTracker = null;
            mDownX = 0;
            mDownY = 0;
            mDownView = null;
            mDownPosition = ListView.INVALID_POSITION;
            mSwiping = false;
            return true;
        }

        if (mVelocityTracker == null) {
            break;
        }

        float deltaX = motionEvent.getRawX() - mDownX;
        float deltaY = motionEvent.getRawY() - mDownY;
        mVelocityTracker.addMovement(motionEvent);
        mVelocityTracker.computeCurrentVelocity(1000);
        float velocityX = mVelocityTracker.getXVelocity();
        float velocityY = mVelocityTracker.getYVelocity();
        float absVelocityX = Math.abs(velocityX);
        float absVelocityY = Math.abs(mVelocityTracker.getYVelocity());
        boolean dismiss = false;
        boolean dismissRight = false;

        if (mIsVertical) {
            if (Math.abs(deltaY) > mViewWidth / 2 && mSwiping) {
                dismiss = true;
                dismissRight = deltaY > 0;
            } else if (mMinFlingVelocity <= absVelocityY && absVelocityY <= mMaxFlingVelocity
                    && absVelocityX < absVelocityY && mSwiping) {
                // dismiss only if flinging in the same direction as dragging
                dismiss = (velocityY < 0) == (deltaY < 0);
                dismissRight = mVelocityTracker.getYVelocity() > 0;
            }
            if (dismiss && mDownPosition != ListView.INVALID_POSITION) {
                // dismiss
                final View downView = mDownView; // mDownView gets null'd before animation ends
                final int downPosition = mDownPosition;
                ++mDismissAnimationRefCount;
                mDownView.animate().translationY(dismissRight ? mViewWidth : -mViewWidth).alpha(0)
                        .setDuration(mAnimationTime).setListener(new AnimatorListenerAdapter() {
                            @Override
                            public void onAnimationEnd(Animator animation) {
                                performDismiss(downView, downPosition);
                            }
                        });
            } else {
                // cancel
                mDownView.animate().translationY(0).alpha(1).setDuration(mAnimationTime).setListener(null);
            }
            mVelocityTracker.recycle();
            mVelocityTracker = null;
            mDownX = 0;
            mDownY = 0;
            mDownView = null;
            mDownPosition = ListView.INVALID_POSITION;
            mSwiping = false;
        } else {

            if (Math.abs(deltaX) > mViewWidth / 2 && mSwiping) {
                dismiss = true;
                dismissRight = deltaX > 0;
            } else if (mMinFlingVelocity <= absVelocityX && absVelocityX <= mMaxFlingVelocity
                    && absVelocityY < absVelocityX && mSwiping) {
                // dismiss only if flinging in the same direction as dragging
                dismiss = (velocityX < 0) == (deltaX < 0);
                dismissRight = mVelocityTracker.getXVelocity() > 0;
            }
            if (dismiss && mDownPosition != ListView.INVALID_POSITION) {
                // dismiss
                final View downView = mDownView; // mDownView gets null'd before animation ends
                final int downPosition = mDownPosition;
                ++mDismissAnimationRefCount;
                mDownView.animate().translationX(dismissRight ? mViewWidth : -mViewWidth).alpha(0)
                        .setDuration(mAnimationTime).setListener(new AnimatorListenerAdapter() {
                            @Override
                            public void onAnimationEnd(Animator animation) {
                                performDismiss(downView, downPosition);
                            }
                        });
            } else {
                // cancel
                mDownView.animate().translationX(0).alpha(1).setDuration(mAnimationTime).setListener(null);
            }
            mVelocityTracker.recycle();
            mVelocityTracker = null;
            mDownX = 0;
            mDownY = 0;
            mDownView = null;
            mDownPosition = ListView.INVALID_POSITION;
            mSwiping = false;
        }
        break;
    }

    case MotionEvent.ACTION_MOVE: {

        if (mVelocityTracker == null || mPaused) {
            break;
        }

        mVelocityTracker.addMovement(motionEvent);
        float deltaX = motionEvent.getRawX() - mDownX;
        float deltaY = motionEvent.getRawY() - mDownY;
        if (mIsVertical) {
            if (Math.abs(deltaY) > mSlop && Math.abs(deltaX) < Math.abs(deltaY) / 2) {
                mSwiping = true;
                mSwipingSlop = (deltaY > 0 ? mSlop : -mSlop);
                mRecyclerView.requestDisallowInterceptTouchEvent(true);

                // Cancel ListView's touch (un-highlighting the item)
                MotionEvent cancelEvent = MotionEvent.obtain(motionEvent);
                cancelEvent.setAction(MotionEvent.ACTION_CANCEL
                        | (motionEvent.getActionIndex() << MotionEvent.ACTION_POINTER_INDEX_SHIFT));
                mRecyclerView.onTouchEvent(cancelEvent);
                cancelEvent.recycle();
            }

            if (mSwiping) {
                mDownView.setTranslationY(deltaY - mSwipingSlop);
                mDownView.setAlpha(Math.max(0f, Math.min(1f, 1f - 2f * Math.abs(deltaY) / mViewWidth)));
                return true;
            }

        } else {
            if (Math.abs(deltaX) > mSlop && Math.abs(deltaY) < Math.abs(deltaX) / 2) {
                mSwiping = true;
                mSwipingSlop = (deltaX > 0 ? mSlop : -mSlop);
                mRecyclerView.requestDisallowInterceptTouchEvent(true);

                // Cancel ListView's touch (un-highlighting the item)
                MotionEvent cancelEvent = MotionEvent.obtain(motionEvent);
                cancelEvent.setAction(MotionEvent.ACTION_CANCEL
                        | (motionEvent.getActionIndex() << MotionEvent.ACTION_POINTER_INDEX_SHIFT));
                mRecyclerView.onTouchEvent(cancelEvent);
                cancelEvent.recycle();
            }

            if (mSwiping) {
                mDownView.setTranslationX(deltaX - mSwipingSlop);
                mDownView.setAlpha(Math.max(0f, Math.min(1f, 1f - 2f * Math.abs(deltaX) / mViewWidth)));
                return true;
            }
        }
        break;
    }
    }
    return false;
}

From source file:cn.goodjobs.common.view.photodraweeview.ScaleDragDetector.java

private void onTouchDragEvent(int action, MotionEvent ev) {
    switch (action) {
    case MotionEvent.ACTION_DOWN: {
        mVelocityTracker = VelocityTracker.obtain();
        if (null != mVelocityTracker) {
            mVelocityTracker.addMovement(ev);
        }//from  www  .  j a va  2  s.  c o  m

        mLastTouchX = getActiveX(ev);
        mLastTouchY = getActiveY(ev);
        mIsDragging = false;
        break;
    }

    case MotionEvent.ACTION_MOVE: {
        final float x = getActiveX(ev);
        final float y = getActiveY(ev);
        final float dx = x - mLastTouchX, dy = y - mLastTouchY;

        if (!mIsDragging) {
            mIsDragging = Math.sqrt((dx * dx) + (dy * dy)) >= mTouchSlop;
        }

        if (mIsDragging) {
            mScaleDragGestureListener.onDrag(dx, dy);
            mLastTouchX = x;
            mLastTouchY = y;

            if (null != mVelocityTracker) {
                mVelocityTracker.addMovement(ev);
            }
        }
        break;
    }

    case MotionEvent.ACTION_CANCEL: {
        if (null != mVelocityTracker) {
            mVelocityTracker.recycle();
            mVelocityTracker = null;
        }
        break;
    }

    case MotionEvent.ACTION_UP: {
        if (mIsDragging) {
            if (null != mVelocityTracker) {
                mLastTouchX = getActiveX(ev);
                mLastTouchY = getActiveY(ev);

                mVelocityTracker.addMovement(ev);
                mVelocityTracker.computeCurrentVelocity(1000);

                final float vX = mVelocityTracker.getXVelocity(), vY = mVelocityTracker.getYVelocity();

                if (Math.max(Math.abs(vX), Math.abs(vY)) >= mMinimumVelocity) {
                    mScaleDragGestureListener.onFling(mLastTouchX, mLastTouchY, -vX, -vY);
                }
            }
        }
        if (null != mVelocityTracker) {
            mVelocityTracker.recycle();
            mVelocityTracker = null;
        }
        break;
    }
    }
}

From source file:ch.tutti.android.bottomsheet.ResolverDrawerLayout.java

public ResolverDrawerLayout(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);

    final TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.ResolverDrawerLayout, defStyleAttr,
            0);/*from ww  w .  j  ava2s . c om*/
    mMaxWidth = a.getDimensionPixelSize(R.styleable.ResolverDrawerLayout_android_maxWidth, -1);
    mMaxCollapsedHeight = a.getDimensionPixelSize(R.styleable.ResolverDrawerLayout_maxCollapsedHeight, 0);
    mMaxCollapsedHeightSmall = a.getDimensionPixelSize(R.styleable.ResolverDrawerLayout_maxCollapsedHeightSmall,
            mMaxCollapsedHeight);
    a.recycle();

    mScroller = new OverScroller(context,
            AnimationUtils.loadInterpolator(context, android.R.interpolator.decelerate_quint));
    mVelocityTracker = VelocityTracker.obtain();

    final ViewConfiguration vc = ViewConfiguration.get(context);
    mTouchSlop = vc.getScaledTouchSlop();
    mMinFlingVelocity = vc.getScaledMinimumFlingVelocity();
}