android.view.VelocityTracker#obtain

Source File: LazyViewPager.java From AndroidBase with Apache License 2.0

6 votes

/**
 * Start a fake drag of the pager.
 *
 * <p>A fake drag can be useful if you want to synchronize the motion of the ViewPager
 * with the touch scrolling of another view, while still letting the ViewPager
 * control the snapping motion and fling behavior. (e.g. parallax-scrolling tabs.)
 * Call {@link #fakeDragBy(float)} to simulate the actual drag motion. Call
 * {@link #endFakeDrag()} to complete the fake drag and fling as necessary.
 *
 * <p>During a fake drag the ViewPager will ignore all touch events. If a real drag
 * is already in progress, this method will return false.
 *
 * @return true if the fake drag began successfully, false if it could not be started.
 *
 * @see #fakeDragBy(float)
 * @see #endFakeDrag()
 */
public boolean beginFakeDrag() {
    if (mIsBeingDragged) {
        return false;
    }
    mFakeDragging = true;
    setScrollState(SCROLL_STATE_DRAGGING);
    mInitialMotionX = mLastMotionX = 0;
    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    } else {
        mVelocityTracker.clear();
    }
    final long time = SystemClock.uptimeMillis();
    final MotionEvent ev = MotionEvent.obtain(time, time, MotionEvent.ACTION_DOWN, 0, 0, 0);
    mVelocityTracker.addMovement(ev);
    ev.recycle();
    mFakeDragBeginTime = time;
    return true;
}

Source File: DirectionalViewpager.java From fangzhuishushenqi with Apache License 2.0

6 votes

/**
 * Start a fake drag of the pager.
 *
 * @return true if the fake drag began successfully, false if it could not be started.
 */
public boolean beginFakeDrag() {
    if (mIsBeingDragged) {
        return false;
    }
    mFakeDragging = true;
    setScrollState(SCROLL_STATE_DRAGGING);
    if (isHorizontal()) {
        mInitialMotionX = mLastMotionX = 0;
    } else {
        mInitialMotionY = mLastMotionY = 0;
    }
    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    } else {
        mVelocityTracker.clear();
    }
    final long time = SystemClock.uptimeMillis();
    final MotionEvent ev = MotionEvent.obtain(time, time, MotionEvent.ACTION_DOWN, 0, 0, 0);
    mVelocityTracker.addMovement(ev);
    ev.recycle();
    mFakeDragBeginTime = time;
    return true;
}

Source File: imgSlider.java From Android-Music-Player with MIT License

5 votes

public imgSlider(Context context, int width, int height) {
    super(context, width, height);
    setBackgroundColor(itemBack.Color0);
    Vx = VelocityTracker.obtain();

    btm = creatImg();
    addView(btm);

    top = creatImg();
    addView(top);

    FMTop = new FMView(getContext(),width,height);
    FMTop.setBackgroundColor(0x66000000);
    FMTop.setClickable(false);
    addView(FMTop);

    Ui.ef.playerEvent.addEvent(new EventCall(new int[]{playerEvents.SONG_CHANGED,playerEvents.PLAYLIST_CHANGED, Ui.ef.Event_onBind}){
        @Override
        public void onCall(int eventId) {
            if(eventId == playerEvents.SONG_CHANGED){
                songChanged();
            }

            if(eventId == Ui.ef.Event_onBind || playerEvents.PLAYLIST_CHANGED == eventId){
                if(Ui.ef.MusicPlayer.handler.list!= null){
                    songChanged();
                }
            }
        }
    });
}

Source File: ItemTouchHelper.java From Telegram-FOSS with GNU General Public License v2.0

5 votes

@SuppressWarnings("WeakerAccess") /* synthetic access */
void obtainVelocityTracker() {
    if (mVelocityTracker != null) {
        mVelocityTracker.recycle();
    }
    mVelocityTracker = VelocityTracker.obtain();
}

Source File: RefreshLayout.java From SimpleProject with MIT License

5 votes

private void initView(Context context) {
	setOrientation(VERTICAL);
	mRefreshStatus = REFRESH_STATUS_NONE;
	mScroller = new Scroller(context);
	mScreenHeight = Resources.getSystem().getDisplayMetrics().heightPixels;
	mVelocityTracker = VelocityTracker.obtain();
	ViewConfiguration configuration = ViewConfiguration.get(context);
	mMinVelocity = configuration.getScaledMinimumFlingVelocity();
}

Source File: WheelView.java From WheelView with Apache License 2.0

5 votes

private void startWheelDrag(MotionEvent event, float x, float y) {
    mIsDraggingWheel = true;
    mDraggedAngle = 0f;

    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    } else {
        mVelocityTracker.clear();
    }
    mVelocityTracker.addMovement(event);

    mAngularVelocity = 0f;
    mLastTouchAngle = mWheelBounds.angleToDegrees(x, y);
}

Source File: DragController.java From LB-Launcher with Apache License 2.0

5 votes

/**
 * Used to create a new DragLayer from XML.
 *
 * @param context The application's context.
 */
public DragController(Launcher launcher) {
    Resources r = launcher.getResources();
    mLauncher = launcher;
    mHandler = new Handler();
    mScrollZone = r.getDimensionPixelSize(R.dimen.scroll_zone);
    mVelocityTracker = VelocityTracker.obtain();

    float density = r.getDisplayMetrics().density;
    mFlingToDeleteThresholdVelocity =
            (int) (r.getInteger(R.integer.config_flingToDeleteMinVelocity) * density);
}

Source File: LWebView.java From ELinkageScroll with Apache License 2.0

4 votes

private void initVelocityTrackerIfNotExists() {
    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
}

Source File: CupcakeGestureDetector.java From light-novel-library_Wenku8_Android with GNU General Public License v2.0

4 votes

@Override
public boolean onTouchEvent(MotionEvent ev) {
    switch (ev.getAction()) {
        case MotionEvent.ACTION_DOWN: {
            mVelocityTracker = VelocityTracker.obtain();
            if (null != mVelocityTracker) {
                mVelocityTracker.addMovement(ev);
            } else {
                Log.i(LOG_TAG, "Velocity tracker is null");
            }

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

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

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

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

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

                    // 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);
                    }
                }
            }

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

    return true;
}

Source File: CupcakeGestureDetector.java From zen4android with MIT License

4 votes

@Override
public boolean onTouchEvent(MotionEvent ev) {
    switch (ev.getAction()) {
        case MotionEvent.ACTION_DOWN: {
            mVelocityTracker = VelocityTracker.obtain();
            if (null != mVelocityTracker) {
                mVelocityTracker.addMovement(ev);
            } else {
                Log.i(LOG_TAG, "Velocity tracker is null");
            }

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

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

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

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

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

                    // 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);
                    }
                }
            }

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

    return true;
}

Source File: RuleView.java From RulerView with Apache License 2.0

4 votes

@Override
public boolean onTouchEvent(MotionEvent event) {
    final int action = event.getAction();
    final int x = (int) event.getX();
    final int y = (int) event.getY();
    logD("onTouchEvent: action=%d", action);
    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
    mVelocityTracker.addMovement(event);
    switch (action) {
        case MotionEvent.ACTION_DOWN:
            mScroller.forceFinished(true);
            mDownX = x;
            isMoved = false;
            break;
        case MotionEvent.ACTION_MOVE:
            final int dx = x - mLastX;

            // 判断是否已经滑动
            if (!isMoved) {
                final int dy = y - mLastY;
                // 滑动的触发条件：水平滑动大于垂直滑动；滑动距离大于阈值
                if (Math.abs(dx) < Math.abs(dy) || Math.abs(x - mDownX) < TOUCH_SLOP) {
                    break;
                }
                isMoved = true;
            }

            mCurrentDistance += -dx;
            calculateValue();
            break;
        case MotionEvent.ACTION_UP:
            // 计算速度：使用1000ms为单位
            mVelocityTracker.computeCurrentVelocity(1000, MAX_FLING_VELOCITY);
            // 获取速度。速度有方向性，水平方向：左滑为负，右滑为正
            int xVelocity = (int) mVelocityTracker.getXVelocity();
            // 达到速度则惯性滑动，否则缓慢滑动到刻度
            if (Math.abs(xVelocity) >= MIN_FLING_VELOCITY) {
                // 速度具有方向性，需要取反
                mScroller.fling((int)mCurrentDistance, 0, -xVelocity, 0,
                        0, (int)mNumberRangeDistance, 0, 0);
                invalidate();
            } else {
                scrollToGradation();
            }
            break;
        default:
            break;
    }
    mLastX = x;
    mLastY = y;
    return true;
}

Source File: ScrollPageAnim.java From NovelReader with MIT License

4 votes

@Override
public boolean onTouchEvent(MotionEvent event) {
    int x = (int) event.getX();
    int y = (int) event.getY();

    // 初始化速度追踪器
    if (mVelocity == null) {
        mVelocity = VelocityTracker.obtain();
    }

    mVelocity.addMovement(event);
    // 设置触碰点
    setTouchPoint(x, y);

    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            isRunning = false;
            // 设置起始点
            setStartPoint(x, y);
            // 停止动画
            abortAnim();
            break;
        case MotionEvent.ACTION_MOVE:
            mVelocity.computeCurrentVelocity(VELOCITY_DURATION);
            isRunning = true;
            // 进行刷新
            mView.postInvalidate();
            break;
        case MotionEvent.ACTION_UP:
            isRunning = false;
            // 开启动画
            startAnim();
            // 删除检测器
            mVelocity.recycle();
            mVelocity = null;
            break;

        case MotionEvent.ACTION_CANCEL:
            try {
                mVelocity.recycle(); // if velocityTracker won't be used should be recycled
                mVelocity = null;
            } catch (Exception e) {
                e.printStackTrace();
            }
            break;
    }
    return true;
}

Source File: PileLayout.java From timecat with Apache License 2.0

4 votes

private void initVelocityTrackerIfNotExists() {
    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
}

Source File: BGAStickyNavLayout.java From AndroidStudyDemo with GNU General Public License v2.0

4 votes

private void initVelocityTrackerIfNotExists() {
    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
}

Source File: AbsHListView.java From Klyph with MIT License

4 votes

private void initVelocityTrackerIfNotExists() {
	if ( mVelocityTracker == null ) {
		mVelocityTracker = VelocityTracker.obtain();
	}
}

Source File: ImageViewActivity.java From Zom-Android-XMPP with GNU General Public License v3.0

4 votes

public ConditionallyEnabledViewPager(Context context) {
    super(context);
    gestureDetectorListener = new SwipeToCloseListener(context);
    gestureDetector = new GestureDetector(context, gestureDetectorListener);
    velocityTracker = VelocityTracker.obtain();
}

Source File: ELinkageScrollLayout.java From ELinkageScroll with Apache License 2.0

4 votes

/**
 * 初始化VelocityTracker
 */
private void initVelocityTrackerIfNotExists() {
    if (mVelocityTracker == null) {
        mVelocityTracker = VelocityTracker.obtain();
    }
}

Source File: CustomGestureDetector.java From Mysplash with GNU Lesser General Public License v3.0

4 votes

private boolean processTouchEvent(MotionEvent ev) {
    final int action = ev.getAction();
    switch (action & MotionEvent.ACTION_MASK) {
        case MotionEvent.ACTION_DOWN:
            mActivePointerId = ev.getPointerId(0);

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

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

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

                if (null != mVelocityTracker) {
                    mVelocityTracker.addMovement(ev);
                }
            }
            break;
        case MotionEvent.ACTION_CANCEL:
            mActivePointerId = INVALID_POINTER_ID;
            // Recycle Velocity Tracker
            if (null != mVelocityTracker) {
                mVelocityTracker.recycle();
                mVelocityTracker = null;
            }
            break;
        case MotionEvent.ACTION_UP:
            mActivePointerId = INVALID_POINTER_ID;
            if (mIsDragging) {
                if (null != mVelocityTracker) {
                    mLastTouchX = getActiveX(ev);
                    mLastTouchY = getActiveY(ev);

                    // 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);
                    }
                }
            }

            // Recycle Velocity Tracker
            if (null != mVelocityTracker) {
                mVelocityTracker.recycle();
                mVelocityTracker = null;
            }
            break;
        case MotionEvent.ACTION_POINTER_UP:
            final int pointerIndex = Util.getPointerIndex(ev.getAction());
            final int pointerId = ev.getPointerId(pointerIndex);
            if (pointerId == mActivePointerId) {
                // This was our active pointer going up. Choose a new
                // active pointer and adjust accordingly.
                final int newPointerIndex = pointerIndex == 0 ? 1 : 0;
                mActivePointerId = ev.getPointerId(newPointerIndex);
                mLastTouchX = ev.getX(newPointerIndex);
                mLastTouchY = ev.getY(newPointerIndex);
            }
            break;
    }

    mActivePointerIndex = ev
            .findPointerIndex(mActivePointerId != INVALID_POINTER_ID ? mActivePointerId
                    : 0);
    return true;
}

Source File: ItemTouchHelperExtension.java From CrazyDaily with Apache License 2.0

4 votes

private void obtainVelocityTracker() {
    if (mVelocityTracker != null) {
        mVelocityTracker.recycle();
    }
    mVelocityTracker = VelocityTracker.obtain();
}

Source File: ScrollFlowLayout.java From FlowHelper with Apache License 2.0

4 votes

@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
    if (!isCanMove){
        return super.onInterceptTouchEvent(ev);
    }
    final ViewParent parent = getParent();
    switch (ev.getAction()) {
        case MotionEvent.ACTION_DOWN:
            if (isVertical()){
                mLastPos = ev.getY();
            }else {
                mLastPos = ev.getX();
            }
            //拿到上次的down坐标
            if (isVertical()){
                mMovePos = ev.getY();
            }else {
                mMovePos = ev.getX();
            }

            if (mScroller != null && !mScroller.isFinished()) {
                mScroller.abortAnimation();
            }

            if (mVelocityTracker != null) {
                mVelocityTracker.recycle();
                mVelocityTracker = null;
            }

            mVelocityTracker = VelocityTracker.obtain();

            mVelocityTracker.addMovement(ev);
            //如果能滚动，应该要屏蔽父控件的触摸事件
            if (parent != null) {
                parent.requestDisallowInterceptTouchEvent(true);
            }

            break;

        case MotionEvent.ACTION_MOVE:
            float offset;
            if (isVerticalMove()){
                offset = ev.getY() - mLastPos;
            }else{
                offset = ev.getX() - mLastPos;
            }
            if (Math.abs(offset) >= mTouchSlop) {
                if (parent != null) {
                    parent.requestDisallowInterceptTouchEvent(true);
                }

                if (mVelocityTracker == null){
                    mVelocityTracker = VelocityTracker.obtain();
                }
                mVelocityTracker.addMovement(ev);
                //由父控件接管触摸事件
                return true;
            }
            if (isVerticalMove()){
                mLastPos = ev.getY();
            }else {
                mLastPos = ev.getX();
            }
            break;

        default:
            break;
    }
    return super.onInterceptTouchEvent(ev);
}

Java Code Examples for android.view.VelocityTracker#obtain()