Example usage for android.support.v4.view ViewCompat getOverScrollMode

List of usage examples for android.support.v4.view ViewCompat getOverScrollMode

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Introduction

In this page you can find the example usage for android.support.v4.view ViewCompat getOverScrollMode.

Prototype

public static int getOverScrollMode(View v)

Source Link

Document

Returns the over-scroll mode for this view.

Usage

From source file:com.cjj.staggeredgridview.StaggeredGridView.java

/**
 * @param deltaY Pixels that content should move by
 * @return true if the movement completed, false if it was stopped prematurely.
 *//* www. j a v  a 2  s.  co m*/
private boolean trackMotionScroll(int deltaY, boolean allowOverScroll) {
    final boolean contentFits = contentFits();
    final int allowOverhang = Math.abs(deltaY);

    final int overScrolledBy;
    int movedBy;

    if (!contentFits) {
        final int overhang;
        final boolean up;
        mPopulating = true;

        if (deltaY > 0) {
            overhang = fillUp(mFirstPosition - 1, allowOverhang) + mItemMargin;
            up = true;
        } else {
            overhang = fillDown(mFirstPosition + getChildCount(), allowOverhang) + mItemMargin;
            up = false;
        }

        movedBy = Math.min(overhang, allowOverhang);
        if (movedBy < 0) {
            movedBy = 0;
        }

        if (movedBy == 0) {
            if (up) {
                mGetToTop = true;
                lazyload = false;
            } else {
                mGetToTop = false;
                lazyload = true;

                if (!loadlock && mLoadListener != null) {
                    mLoadListener.onLoadmore();
                    loadlock = true;
                }
            }
        } else {
            mGetToTop = false;
            lazyload = true;
        }

        offsetChildren(up ? movedBy : -movedBy);
        if (getChildCount() > MAX_CHILD_COUNT) {
            recycleOffscreenViews();
        }

        mPopulating = false;
        overScrolledBy = allowOverhang - overhang;

    } else {
        overScrolledBy = allowOverhang;
        movedBy = 0;
    }

    if (allowOverScroll) {
        final int overScrollMode = ViewCompat.getOverScrollMode(this);

        if (overScrollMode == ViewCompat.OVER_SCROLL_ALWAYS
                || (overScrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && !contentFits)) {
            if (overScrolledBy > 0) {
                EdgeEffectCompat edge = deltaY > 0 ? mTopEdge : mBottomEdge;
                edge.onPull((float) Math.abs(deltaY) / getHeight());
                invalidate();
            }
        }
    }

    if (mSelectorPosition != INVALID_POSITION) {
        final int childIndex = mSelectorPosition - mFirstPosition;
        if (childIndex >= 0 && childIndex < getChildCount()) {
            positionSelector(INVALID_POSITION, getChildAt(childIndex));
        }
    } else {
        mSelectorRect.setEmpty();
    }

    return deltaY == 0 || movedBy != 0;
}

From source file:com.skurro.pricesnapp1.staggeredgridview.StaggeredGridView.java

/**
 * @param deltaY Pixels that content should move by
 * @return true if the movement completed, false if it was stopped prematurely.
 *///from   w  w  w. ja  v a 2s  .  co m
private boolean trackMotionScroll(int deltaY, boolean allowOverScroll) {
    final boolean contentFits = contentFits();
    final int allowOverhang = Math.abs(deltaY);

    final int overScrolledBy;
    int movedBy;

    if (!contentFits) {
        final int overhang;
        final boolean up;
        mPopulating = true;

        if (deltaY > 0) {
            overhang = fillUp(mFirstPosition - 1, allowOverhang) + mItemMargin;
            up = true;
        } else {
            overhang = fillDown(mFirstPosition + getChildCount(), allowOverhang) + mItemMargin;
            up = false;
        }

        movedBy = Math.min(overhang, allowOverhang);
        if (movedBy < 0) {
            movedBy = 0;
        }

        if (movedBy == 0) {
            if (up) {
                mGetToTop = true;
                lazyload = false;

            } else {
                mGetToTop = false;
                lazyload = true;

                if (!loadlock) {

                    mLoadListener.onLoadmore();
                    loadlock = true;
                }
            }
        } else {
            mGetToTop = false;
            lazyload = true;
        }

        offsetChildren(up ? movedBy : -movedBy);
        if (getChildCount() > MAX_CHILD_COUNT) {
            recycleOffscreenViews();
        }

        mPopulating = false;
        overScrolledBy = allowOverhang - overhang;

    } else {
        overScrolledBy = allowOverhang;
        movedBy = 0;
    }

    if (allowOverScroll) {
        final int overScrollMode = ViewCompat.getOverScrollMode(this);

        if (overScrollMode == ViewCompat.OVER_SCROLL_ALWAYS
                || (overScrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && !contentFits)) {
            if (overScrolledBy > 0) {
                EdgeEffectCompat edge = deltaY > 0 ? mTopEdge : mBottomEdge;
                edge.onPull((float) Math.abs(deltaY) / getHeight());
                invalidate();
            }
        }
    }

    if (mSelectorPosition != INVALID_POSITION) {
        final int childIndex = mSelectorPosition - mFirstPosition;
        if (childIndex >= 0 && childIndex < getChildCount()) {
            positionSelector(INVALID_POSITION, getChildAt(childIndex));
        }
    } else {
        mSelectorRect.setEmpty();
    }

    /* HERE we call onScroll */

    if (mOnScrollLis != null) {
        mOnScrollLis.onScroll(this, getFirstPosition(), getChildCount(), this.mItemCount);
        mOnScrollLis.onScrollStateChanged(this, 0);
    }

    return deltaY == 0 || movedBy != 0;
}

From source file:com.hxqc.mall.core.views.CustomScrollView.java

@Override
public boolean onTouchEvent(MotionEvent ev) {
    initVelocityTrackerIfNotExists();/*from   ww w.j a va  2  s . c o m*/

    MotionEvent vtev = MotionEvent.obtain(ev);

    final int actionMasked = MotionEventCompat.getActionMasked(ev);

    if (actionMasked == MotionEvent.ACTION_DOWN) {
        mNestedYOffset = 0;
    }
    vtev.offsetLocation(0, mNestedYOffset);

    switch (actionMasked) {
    case MotionEvent.ACTION_DOWN: {
        if (getChildCount() == 0) {
            return false;
        }
        if ((mIsBeingDragged = !mScroller.isFinished())) {
            final ViewParent parent = getParent();
            if (parent != null) {
                parent.requestDisallowInterceptTouchEvent(true);
            }
        }

        /*
         * If being flinged and user touches, stop the fling. isFinished
         * will be false if being flinged.
         */
        if (!mScroller.isFinished()) {
            mScroller.abortAnimation();
        }

        // Remember where the motion event started
        mLastMotionY = (int) ev.getY();
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        startNestedScroll(ViewCompat.SCROLL_AXIS_VERTICAL);
        break;
    }
    case MotionEvent.ACTION_MOVE:
        final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
        if (activePointerIndex == -1) {
            DebugLog.e(TAG, "Invalid pointerId=" + mActivePointerId + " in onTouchEvent");
            break;
        }

        final int y = (int) MotionEventCompat.getY(ev, activePointerIndex);
        int deltaY = mLastMotionY - y;
        if (dispatchNestedPreScroll(0, deltaY, mScrollConsumed, mScrollOffset)) {
            deltaY -= mScrollConsumed[1];
            vtev.offsetLocation(0, mScrollOffset[1]);
            mNestedYOffset += mScrollOffset[1];
        }
        if (!mIsBeingDragged && Math.abs(deltaY) > mTouchSlop) {
            final ViewParent parent = getParent();
            if (parent != null) {
                parent.requestDisallowInterceptTouchEvent(true);
            }
            mIsBeingDragged = true;
            if (deltaY > 0) {
                deltaY -= mTouchSlop;
            } else {
                deltaY += mTouchSlop;
            }
        }
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            mLastMotionY = y - mScrollOffset[1];

            final int oldY = getScrollY();
            final int range = getScrollRange();
            final int overscrollMode = ViewCompat.getOverScrollMode(this);
            boolean canOverscroll = overscrollMode == ViewCompat.OVER_SCROLL_ALWAYS
                    || (overscrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && range > 0);

            // Calling overScrollByCompat will call onOverScrolled, which
            // calls onScrollChanged if applicable.
            if (overScrollByCompat(0, deltaY, 0, getScrollY(), 0, range, 0, 0, true)
                    && !hasNestedScrollingParent()) {
                // Break our velocity if we hit a scroll barrier.
                mVelocityTracker.clear();
            }

            final int scrolledDeltaY = getScrollY() - oldY;
            final int unconsumedY = deltaY - scrolledDeltaY;
            if (dispatchNestedScroll(0, scrolledDeltaY, 0, unconsumedY, mScrollOffset)) {
                mLastMotionY -= mScrollOffset[1];
                vtev.offsetLocation(0, mScrollOffset[1]);
                mNestedYOffset += mScrollOffset[1];
            } else if (canOverscroll) {
                ensureGlows();
                final int pulledToY = oldY + deltaY;
                if (pulledToY < 0) {
                    mEdgeGlowTop.onPull((float) deltaY / getHeight(),
                            MotionEventCompat.getX(ev, activePointerIndex) / getWidth());
                    if (!mEdgeGlowBottom.isFinished()) {
                        mEdgeGlowBottom.onRelease();
                    }
                } else if (pulledToY > range) {
                    mEdgeGlowBottom.onPull((float) deltaY / getHeight(),
                            1.f - MotionEventCompat.getX(ev, activePointerIndex) / getWidth());
                    if (!mEdgeGlowTop.isFinished()) {
                        mEdgeGlowTop.onRelease();
                    }
                }
                if (mEdgeGlowTop != null && (!mEdgeGlowTop.isFinished() || !mEdgeGlowBottom.isFinished())) {
                    ViewCompat.postInvalidateOnAnimation(this);
                }
            }
        }
        break;
    case MotionEvent.ACTION_UP:
        if (mIsBeingDragged) {
            final VelocityTracker velocityTracker = mVelocityTracker;
            velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            int initialVelocity = (int) VelocityTrackerCompat.getYVelocity(velocityTracker, mActivePointerId);

            if ((Math.abs(initialVelocity) > mMinimumVelocity)) {
                flingWithNestedDispatch(-initialVelocity);
            }

            mActivePointerId = INVALID_POINTER;
            endDrag();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged && getChildCount() > 0) {
            mActivePointerId = INVALID_POINTER;
            endDrag();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);
        mLastMotionY = (int) MotionEventCompat.getY(ev, index);
        mActivePointerId = MotionEventCompat.getPointerId(ev, index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        mLastMotionY = (int) MotionEventCompat.getY(ev,
                MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        break;
    }

    if (mVelocityTracker != null) {
        mVelocityTracker.addMovement(vtev);
    }
    vtev.recycle();
    return true;
}

From source file:org.nekC.android.support.widget.RecyclerView.java

public RecyclerView(Context context, @Nullable AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    setFocusableInTouchMode(true);/*ww w.  j ava  2  s  .  com*/
    final int version = Build.VERSION.SDK_INT;
    mPostUpdatesOnAnimation = version >= 16;

    final ViewConfiguration vc = ViewConfiguration.get(context);
    mTouchSlop = vc.getScaledTouchSlop();
    mMinFlingVelocity = vc.getScaledMinimumFlingVelocity();
    mMaxFlingVelocity = vc.getScaledMaximumFlingVelocity();
    setWillNotDraw(ViewCompat.getOverScrollMode(this) == ViewCompat.OVER_SCROLL_NEVER);

    mItemAnimator.setListener(mItemAnimatorListener);
    initAdapterManager();
    initChildrenHelper();
    // If not explicitly specified this view is important for accessibility.
    if (ViewCompat.getImportantForAccessibility(this) == ViewCompat.IMPORTANT_FOR_ACCESSIBILITY_AUTO) {
        ViewCompat.setImportantForAccessibility(this, ViewCompat.IMPORTANT_FOR_ACCESSIBILITY_YES);
    }
    mAccessibilityManager = (AccessibilityManager) getContext().getSystemService(Context.ACCESSIBILITY_SERVICE);
    setAccessibilityDelegateCompat(new RecyclerViewAccessibilityDelegate(this));
    // Create the layoutManager if specified.

    mScrollingChildHelper = new NestedScrollingChildHelper(this);
    setNestedScrollingEnabled(true);
}

From source file:org.lee.pulltorefresh.library.View.StaggeredGridView.java

/**
 * @param deltaY/*www  . jav  a 2s  .co m*/
 *            Pixels that content should move by
 * @return true if the movement completed, false if it was stopped
 *         prematurely.
 */
private boolean trackMotionScroll(int deltaY, boolean allowOverScroll) {
    final boolean contentFits = contentFits();
    final int allowOverhang = Math.abs(deltaY);

    final int overScrolledBy;
    int movedBy;

    if (!contentFits) {
        final int overhang;
        final boolean up;
        mPopulating = true;

        if (deltaY > 0) {
            overhang = fillUp(mFirstPosition - 1, allowOverhang) + mItemMargin;
            up = true;
        } else {
            overhang = fillDown(mFirstPosition + getChildCount(), allowOverhang) + mItemMargin;
            up = false;
        }

        movedBy = Math.min(overhang, allowOverhang);
        if (movedBy < 0) {
            movedBy = 0;
        }

        if (movedBy == 0) {
            if (up) {
                mGetToTop = true;
                lazyload = false;
            } else {
                mGetToTop = false;
                lazyload = true;

                if (!loadlock) {
                    if (mLoadListener != null) {
                        mLoadListener.onLoadmore();
                    }
                    loadlock = true;
                }
            }
        } else {
            mGetToTop = false;
            lazyload = true;
        }

        offsetChildren(up ? movedBy : -movedBy);
        if (getChildCount() > MAX_CHILD_COUNT) {
            recycleOffscreenViews();
        }

        mPopulating = false;
        overScrolledBy = allowOverhang - overhang;

    } else {
        overScrolledBy = allowOverhang;
        movedBy = 0;
    }

    if (allowOverScroll) {
        final int overScrollMode = ViewCompat.getOverScrollMode(this);

        if (overScrollMode == ViewCompat.OVER_SCROLL_ALWAYS
                || (overScrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && !contentFits)) {
            if (overScrolledBy > 0) {
                EdgeEffectCompat edge = deltaY > 0 ? mTopEdge : mBottomEdge;
                edge.onPull((float) Math.abs(deltaY) / getHeight());
                invalidate();
            }
        }
    }

    if (mSelectorPosition != INVALID_POSITION) {
        final int childIndex = mSelectorPosition - mFirstPosition;
        if (childIndex >= 0 && childIndex < getChildCount()) {
            positionSelector(INVALID_POSITION, getChildAt(childIndex));
        }
    } else {
        mSelectorRect.setEmpty();
    }

    return deltaY == 0 || movedBy != 0;
}

From source file:com.hxqc.mall.thirdshop.views.CustomScrollView.java

@Override
public boolean onTouchEvent(MotionEvent ev) {
    initVelocityTrackerIfNotExists();//from ww  w . j  a  va  2  s . c o  m

    MotionEvent vtev = MotionEvent.obtain(ev);

    final int actionMasked = MotionEventCompat.getActionMasked(ev);

    if (actionMasked == MotionEvent.ACTION_DOWN) {
        mNestedYOffset = 0;
    }
    vtev.offsetLocation(0, mNestedYOffset);

    switch (actionMasked) {
    case MotionEvent.ACTION_DOWN: {
        if (getChildCount() == 0) {
            return false;
        }
        if ((mIsBeingDragged = !mScroller.isFinished())) {
            final ViewParent parent = getParent();
            if (parent != null) {
                parent.requestDisallowInterceptTouchEvent(true);
            }
        }

        /*
         * If being flinged and user touches, stop the fling. isFinished
         * will be false if being flinged.
         */
        if (!mScroller.isFinished()) {
            mScroller.abortAnimation();
        }

        // Remember where the motion event started
        mLastMotionY = (int) ev.getY();
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        startNestedScroll(ViewCompat.SCROLL_AXIS_VERTICAL);
        break;
    }
    case MotionEvent.ACTION_MOVE:
        final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
        if (activePointerIndex == -1) {
            DebugLog.e(TAG, "Invalid pointerId=" + mActivePointerId + " in onTouchEvent");
            break;
        }

        final int y = (int) MotionEventCompat.getY(ev, activePointerIndex);
        int deltaY = mLastMotionY - y;
        if (dispatchNestedPreScroll(0, deltaY, mScrollConsumed, mScrollOffset)) {
            deltaY -= mScrollConsumed[1];
            vtev.offsetLocation(0, mScrollOffset[1]);
            mNestedYOffset += mScrollOffset[1];
        }
        if (!mIsBeingDragged && Math.abs(deltaY) > mTouchSlop) {
            final ViewParent parent = getParent();
            if (parent != null) {
                parent.requestDisallowInterceptTouchEvent(true);
            }
            mIsBeingDragged = true;
            if (deltaY > 0) {
                deltaY -= mTouchSlop;
            } else {
                deltaY += mTouchSlop;
            }
        }
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            mLastMotionY = y - mScrollOffset[1];

            final int oldY = getScrollY();
            final int range = getScrollRange();
            final int overscrollMode = ViewCompat.getOverScrollMode(this);
            boolean canOverscroll = overscrollMode == ViewCompat.OVER_SCROLL_ALWAYS
                    || (overscrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && range > 0);

            // Calling overScrollByCompat will call onOverScrolled, which
            // calls onScrollChanged if applicable.
            if (overScrollByCompat(0, deltaY, 0, getScrollY(), 0, range, 0, 0, true)
                    && !hasNestedScrollingParent()) {
                // Break our velocity if we hit a scroll barrier.
                mVelocityTracker.clear();
            }

            final int scrolledDeltaY = getScrollY() - oldY;
            final int unconsumedY = deltaY - scrolledDeltaY;
            if (dispatchNestedScroll(0, scrolledDeltaY, 0, unconsumedY, mScrollOffset)) {
                mLastMotionY -= mScrollOffset[1];
                vtev.offsetLocation(0, mScrollOffset[1]);
                mNestedYOffset += mScrollOffset[1];
            } else if (canOverscroll) {
                ensureGlows();
                final int pulledToY = oldY + deltaY;
                if (pulledToY < 0) {
                    mEdgeGlowTop.onPull((float) deltaY / getHeight(),
                            MotionEventCompat.getX(ev, activePointerIndex) / getWidth());
                    if (!mEdgeGlowBottom.isFinished()) {
                        mEdgeGlowBottom.onRelease();
                    }
                } else if (pulledToY > range) {
                    mEdgeGlowBottom.onPull((float) deltaY / getHeight(),
                            1.f - MotionEventCompat.getX(ev, activePointerIndex) / getWidth());
                    if (!mEdgeGlowTop.isFinished()) {
                        mEdgeGlowTop.onRelease();
                    }
                }
                if (mEdgeGlowTop != null && (!mEdgeGlowTop.isFinished() || !mEdgeGlowBottom.isFinished())) {
                    ViewCompat.postInvalidateOnAnimation(this);
                }
            }
        }
        break;
    case MotionEvent.ACTION_UP:
        if (mIsBeingDragged) {
            final VelocityTracker velocityTracker = mVelocityTracker;
            velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            int initialVelocity = (int) VelocityTrackerCompat.getYVelocity(velocityTracker, mActivePointerId);

            if ((Math.abs(initialVelocity) > mMinimumVelocity)) {
                flingWithNestedDispatch(-initialVelocity);
            }

            mActivePointerId = INVALID_POINTER;
            endDrag();
        }
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged && getChildCount() > 0) {
            mActivePointerId = INVALID_POINTER;
            endDrag();
        }
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);
        mLastMotionY = (int) MotionEventCompat.getY(ev, index);
        mActivePointerId = MotionEventCompat.getPointerId(ev, index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        mLastMotionY = (int) MotionEventCompat.getY(ev,
                MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        break;
    default:
        break;
    }

    if (mVelocityTracker != null) {
        mVelocityTracker.addMovement(vtev);
    }
    vtev.recycle();
    return true;
}

From source file:com.app.afteryou.ui.staggered.StaggeredGridView.java

/**
 * // w ww  .ja v a 2  s .  co m
 * @param deltaY
 *            Pixels that content should move by
 * @return true if the movement completed, false if it was stopped
 *         prematurely.
 */
private boolean trackMotionScroll(int deltaY, boolean allowOverScroll) {
    final boolean contentFits = contentFits();
    final int allowOverhang = Math.abs(deltaY);

    final int overScrolledBy;
    final int movedBy;
    if (!contentFits) {
        final int overhang;
        final boolean up;
        mPopulating = true;
        if (deltaY > 0) {
            overhang = fillUp(mFirstPosition - 1, allowOverhang) + mItemMargin;
            up = true;
        } else {
            overhang = fillDown(mFirstPosition + getChildCount(), allowOverhang) + mItemMargin;
            up = false;
        }
        movedBy = Math.min(overhang, allowOverhang);
        offsetChildren(up ? movedBy : -movedBy);
        //recycleOffscreenViews();
        mPopulating = false;
        overScrolledBy = allowOverhang - overhang;
    } else {
        overScrolledBy = allowOverhang;
        movedBy = 0;
    }

    if (allowOverScroll) {
        final int overScrollMode = ViewCompat.getOverScrollMode(this);

        if (overScrollMode == ViewCompat.OVER_SCROLL_ALWAYS
                || (overScrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && !contentFits)) {

            if (overScrolledBy > 0) {
                EdgeEffectCompat edge = deltaY > 0 ? mTopEdge : mBottomEdge;
                edge.onPull((float) Math.abs(deltaY) / getHeight());
                ViewCompat.postInvalidateOnAnimation(this);
            }
        }
    }

    if (mSelectorPosition != INVALID_POSITION) {
        final int childIndex = mSelectorPosition - mFirstPosition;
        if (childIndex >= 0 && childIndex < getChildCount()) {
            positionSelector(INVALID_POSITION, getChildAt(childIndex));
        }
    } else {
        mSelectorRect.setEmpty();
    }
    invokeOnItemScrollListener();
    return deltaY == 0 || movedBy != 0;
}

From source file:com.goftagram.telegram.messenger.support.widget.RecyclerView.java

public RecyclerView(Context context, @Nullable AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    setScrollContainer(true);// www  . j  a v a2  s . c om
    setFocusableInTouchMode(true);
    final int version = Build.VERSION.SDK_INT;
    mPostUpdatesOnAnimation = version >= 16;

    final ViewConfiguration vc = ViewConfiguration.get(context);
    mTouchSlop = vc.getScaledTouchSlop();
    mMinFlingVelocity = vc.getScaledMinimumFlingVelocity();
    mMaxFlingVelocity = vc.getScaledMaximumFlingVelocity();
    setWillNotDraw(ViewCompat.getOverScrollMode(this) == ViewCompat.OVER_SCROLL_NEVER);

    mItemAnimator.setListener(mItemAnimatorListener);
    initAdapterManager();
    initChildrenHelper();
    // If not explicitly specified this view is important for accessibility.
    if (ViewCompat.getImportantForAccessibility(this) == ViewCompat.IMPORTANT_FOR_ACCESSIBILITY_AUTO) {
        ViewCompat.setImportantForAccessibility(this, ViewCompat.IMPORTANT_FOR_ACCESSIBILITY_YES);
    }
    mAccessibilityManager = (AccessibilityManager) getContext().getSystemService(Context.ACCESSIBILITY_SERVICE);
    setAccessibilityDelegateCompat(new RecyclerViewAccessibilityDelegate(this));

    mScrollingChildHelper = new NestedScrollingChildHelper(this);
    setNestedScrollingEnabled(true);
}

From source file:mrfu.blurstaggered.lib.view.StaggeredGridView.java

/**
 * @param deltaY Pixels that content should move by
 * @return true if the movement completed, false if it was stopped prematurely.
 *///w  w  w  .  java2s . c o m
private boolean trackMotionScroll(int deltaY, boolean allowOverScroll) {
    final boolean contentFits = contentFits();
    final int allowOverhang = Math.abs(deltaY);

    final int overScrolledBy;
    int movedBy;

    if (!contentFits) {
        final int overhang;
        final boolean up;
        mPopulating = true;

        if (deltaY > 0) {
            overhang = fillUp(mFirstPosition - 1, allowOverhang) + mItemMargin;
            up = true;
        } else {
            overhang = fillDown(mFirstPosition + getChildCount(), allowOverhang) + mItemMargin;
            up = false;
        }

        movedBy = Math.min(overhang, allowOverhang);
        if (movedBy < 0) {
            movedBy = 0;
        }

        if (movedBy == 0) {
            if (up) {
                mGetToTop = true;
                lazyload = false;
            } else {
                mGetToTop = false;
                lazyload = true;

                if (!loadlock) {
                    //                        mLoadListener.onLoadmore();
                    loadlock = true;
                }
            }
        } else {
            mGetToTop = false;
            lazyload = true;
        }

        offsetChildren(up ? movedBy : -movedBy);
        if (getChildCount() > MAX_CHILD_COUNT) {
            recycleOffscreenViews();
        }

        mPopulating = false;
        overScrolledBy = allowOverhang - overhang;

    } else {
        overScrolledBy = allowOverhang;
        movedBy = 0;
    }

    if (allowOverScroll) {
        final int overScrollMode = ViewCompat.getOverScrollMode(this);

        if (overScrollMode == ViewCompat.OVER_SCROLL_ALWAYS
                || (overScrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && !contentFits)) {
            if (overScrolledBy > 0) {
                EdgeEffectCompat edge = deltaY > 0 ? mTopEdge : mBottomEdge;
                edge.onPull((float) Math.abs(deltaY) / getHeight());
                invalidate();
            }
        }
    }

    if (mSelectorPosition != INVALID_POSITION) {
        final int childIndex = mSelectorPosition - mFirstPosition;
        if (childIndex >= 0 && childIndex < getChildCount()) {
            positionSelector(INVALID_POSITION, getChildAt(childIndex));
        }
    } else {
        mSelectorRect.setEmpty();
    }

    //TODO MrFu
    invokeOnItemScrollListener();

    return deltaY == 0 || movedBy != 0;
}

From source file:com.apptentive.android.sdk.view.ApptentiveNestedScrollView.java

@Override
public boolean onTouchEvent(MotionEvent ev) {
    initVelocityTrackerIfNotExists();/*from w  w w  .  j ava 2 s.  co  m*/

    MotionEvent vtev = MotionEvent.obtain(ev);

    final int actionMasked = MotionEventCompat.getActionMasked(ev);

    if (actionMasked == MotionEvent.ACTION_DOWN) {
        mNestedYOffset = 0;
    }
    vtev.offsetLocation(0, mNestedYOffset);

    switch (actionMasked) {
    case MotionEvent.ACTION_DOWN: {
        if (getChildCount() == 0) {
            return false;
        }
        if ((mIsBeingDragged = !mScroller.isFinished())) {
            final ViewParent parent = getParent();
            if (parent != null) {
                parent.requestDisallowInterceptTouchEvent(true);
            }
        }

        /*
         * If being flinged and user touches, stop the fling. isFinished
         * will be false if being flinged.
         */
        if (!mScroller.isFinished()) {
            mScroller.abortAnimation();
        }

        // Remember where the motion event started
        mLastMotionY = (int) ev.getY();
        mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
        startNestedScroll(ViewCompat.SCROLL_AXIS_VERTICAL);
        break;
    }
    case MotionEvent.ACTION_MOVE:
        final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
        if (activePointerIndex == -1) {
            Log.e(TAG, "Invalid pointerId=" + mActivePointerId + " in onTouchEvent");
            break;
        }

        final int y = (int) MotionEventCompat.getY(ev, activePointerIndex);
        int deltaY = mLastMotionY - y;
        if (dispatchNestedPreScroll(0, deltaY, mScrollConsumed, mScrollOffset)) {
            deltaY -= mScrollConsumed[1];
            vtev.offsetLocation(0, mScrollOffset[1]);
            mNestedYOffset += mScrollOffset[1];
        }
        if (!mIsBeingDragged && Math.abs(deltaY) > mTouchSlop) {
            final ViewParent parent = getParent();
            if (parent != null) {
                parent.requestDisallowInterceptTouchEvent(true);
            }
            mIsBeingDragged = true;
            if (deltaY > 0) {
                deltaY -= mTouchSlop;
            } else {
                deltaY += mTouchSlop;
            }
        }
        if (mIsBeingDragged) {
            // Scroll to follow the motion event
            mLastMotionY = y - mScrollOffset[1];

            final int oldY = getScrollY();
            final int range = getScrollRange();
            final int overscrollMode = ViewCompat.getOverScrollMode(this);
            boolean canOverscroll = overscrollMode == ViewCompat.OVER_SCROLL_ALWAYS
                    || (overscrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && range > 0);

            // Calling overScrollByCompat will call onOverScrolled, which
            // calls onScrollChanged if applicable.
            if (overScrollByCompat(0, deltaY, 0, getScrollY(), 0, range, 0, 0, true)
                    && !hasNestedScrollingParent()) {
                // Break our velocity if we hit a scroll barrier.
                mVelocityTracker.clear();
            }

            final int scrolledDeltaY = getScrollY() - oldY;
            final int unconsumedY = deltaY - scrolledDeltaY;
            if (dispatchNestedScroll(0, scrolledDeltaY, 0, unconsumedY, mScrollOffset)) {
                mLastMotionY -= mScrollOffset[1];
                vtev.offsetLocation(0, mScrollOffset[1]);
                mNestedYOffset += mScrollOffset[1];
            } else if (canOverscroll) {
                ensureGlows();
                final int pulledToY = oldY + deltaY;
                if (pulledToY < 0) {
                    mEdgeGlowTop.onPull((float) deltaY / getHeight(),
                            MotionEventCompat.getX(ev, activePointerIndex) / getWidth());
                    if (!mEdgeGlowBottom.isFinished()) {
                        mEdgeGlowBottom.onRelease();
                    }
                } else if (pulledToY > range) {
                    mEdgeGlowBottom.onPull((float) deltaY / getHeight(),
                            1.f - MotionEventCompat.getX(ev, activePointerIndex) / getWidth());
                    if (!mEdgeGlowTop.isFinished()) {
                        mEdgeGlowTop.onRelease();
                    }
                }
                if (mEdgeGlowTop != null && (!mEdgeGlowTop.isFinished() || !mEdgeGlowBottom.isFinished())) {
                    ViewCompat.postInvalidateOnAnimation(this);
                }
            }
        }
        break;
    case MotionEvent.ACTION_UP:
        if (mIsBeingDragged) {
            final VelocityTracker velocityTracker = mVelocityTracker;
            velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
            int initialVelocity = (int) VelocityTrackerCompat.getYVelocity(velocityTracker, mActivePointerId);

            if ((Math.abs(initialVelocity) > mMinimumVelocity)) {
                flingWithNestedDispatch(-initialVelocity);
            } else if (mScroller.springBack(getScrollX(), getScrollY(), 0, 0, 0, getScrollRange())) {
                ViewCompat.postInvalidateOnAnimation(this);
            }
        }
        mActivePointerId = INVALID_POINTER;
        endDrag();
        break;
    case MotionEvent.ACTION_CANCEL:
        if (mIsBeingDragged && getChildCount() > 0) {
            if (mScroller.springBack(getScrollX(), getScrollY(), 0, 0, 0, getScrollRange())) {
                ViewCompat.postInvalidateOnAnimation(this);
            }
        }
        mActivePointerId = INVALID_POINTER;
        endDrag();
        break;
    case MotionEventCompat.ACTION_POINTER_DOWN: {
        final int index = MotionEventCompat.getActionIndex(ev);
        mLastMotionY = (int) MotionEventCompat.getY(ev, index);
        mActivePointerId = MotionEventCompat.getPointerId(ev, index);
        break;
    }
    case MotionEventCompat.ACTION_POINTER_UP:
        onSecondaryPointerUp(ev);
        mLastMotionY = (int) MotionEventCompat.getY(ev,
                MotionEventCompat.findPointerIndex(ev, mActivePointerId));
        break;
    }

    if (mVelocityTracker != null) {
        mVelocityTracker.addMovement(vtev);
    }
    vtev.recycle();
    return true;
}