diff options
Diffstat (limited to 'core/java/android/widget/ScrollView.java')
| -rw-r--r-- | core/java/android/widget/ScrollView.java | 76 |
1 files changed, 61 insertions, 15 deletions
diff --git a/core/java/android/widget/ScrollView.java b/core/java/android/widget/ScrollView.java index 082d728..34a6a40 100644 --- a/core/java/android/widget/ScrollView.java +++ b/core/java/android/widget/ScrollView.java @@ -138,6 +138,12 @@ public class ScrollView extends FrameLayout { private int mActivePointerId = INVALID_POINTER; /** + * Used during scrolling to retrieve the new offset within the window. + */ + private final int[] mScrollOffset = new int[2]; + private final int[] mScrollConsumed = new int[2]; + + /** * The StrictMode "critical time span" objects to catch animation * stutters. Non-null when a time-sensitive animation is * in-flight. Must call finish() on them when done animating. @@ -505,7 +511,7 @@ public class ScrollView extends FrameLayout { final int y = (int) ev.getY(pointerIndex); final int yDiff = Math.abs(y - mLastMotionY); - if (yDiff > mTouchSlop) { + if (yDiff > mTouchSlop && (getNestedScrollAxes() & SCROLL_AXIS_VERTICAL) == 0) { mIsBeingDragged = true; mLastMotionY = y; initVelocityTrackerIfNotExists(); @@ -606,6 +612,7 @@ public class ScrollView extends FrameLayout { // Remember where the motion event started mLastMotionY = (int) ev.getY(); mActivePointerId = ev.getPointerId(0); + startNestedScroll(SCROLL_AXIS_VERTICAL); break; } case MotionEvent.ACTION_MOVE: @@ -617,6 +624,9 @@ public class ScrollView extends FrameLayout { final int y = (int) ev.getY(activePointerIndex); int deltaY = mLastMotionY - y; + if (dispatchNestedPreScroll(0, deltaY, mScrollConsumed, mScrollOffset)) { + deltaY -= mScrollConsumed[1] + mScrollOffset[1]; + } if (!mIsBeingDragged && Math.abs(deltaY) > mTouchSlop) { final ViewParent parent = getParent(); if (parent != null) { @@ -633,22 +643,25 @@ public class ScrollView extends FrameLayout { // Scroll to follow the motion event mLastMotionY = y; - final int oldX = mScrollX; final int oldY = mScrollY; final int range = getScrollRange(); final int overscrollMode = getOverScrollMode(); - final boolean canOverscroll = overscrollMode == OVER_SCROLL_ALWAYS || + boolean canOverscroll = overscrollMode == OVER_SCROLL_ALWAYS || (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && range > 0); // Calling overScrollBy will call onOverScrolled, which // calls onScrollChanged if applicable. - if (overScrollBy(0, deltaY, 0, mScrollY, - 0, range, 0, mOverscrollDistance, true)) { + if (overScrollBy(0, deltaY, 0, mScrollY, 0, range, 0, mOverscrollDistance, true) + && !hasNestedScrollingParent()) { // Break our velocity if we hit a scroll barrier. mVelocityTracker.clear(); } - if (canOverscroll) { + final int scrolledDeltaY = mScrollY - oldY; + final int unconsumedY = deltaY - scrolledDeltaY; + if (dispatchNestedScroll(0, scrolledDeltaY, 0, unconsumedY, mScrollOffset)) { + mLastMotionY -= mScrollOffset[1]; + } else if (canOverscroll) { final int pulledToY = oldY + deltaY; if (pulledToY < 0) { mEdgeGlowTop.onPull((float) deltaY / getHeight()); @@ -674,15 +687,11 @@ public class ScrollView extends FrameLayout { velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); int initialVelocity = (int) velocityTracker.getYVelocity(mActivePointerId); - if (getChildCount() > 0) { - if ((Math.abs(initialVelocity) > mMinimumVelocity)) { - fling(-initialVelocity); - } else { - if (mScroller.springBack(mScrollX, mScrollY, 0, 0, 0, - getScrollRange())) { - postInvalidateOnAnimation(); - } - } + if ((Math.abs(initialVelocity) > mMinimumVelocity)) { + flingWithNestedDispatch(-initialVelocity); + } else if (mScroller.springBack(mScrollX, mScrollY, 0, 0, 0, + getScrollRange())) { + postInvalidateOnAnimation(); } mActivePointerId = INVALID_POINTER; @@ -1553,6 +1562,15 @@ public class ScrollView extends FrameLayout { } } + private void flingWithNestedDispatch(int velocityY) { + if (mScrollY == 0 && velocityY < 0 || + mScrollY == getScrollRange() && velocityY > 0) { + dispatchNestedFling(0, velocityY); + } else { + fling(velocityY); + } + } + private void endDrag() { mIsBeingDragged = false; @@ -1603,6 +1621,34 @@ public class ScrollView extends FrameLayout { } @Override + public boolean onStartNestedScroll(View child, View target, int nestedScrollAxes) { + return (nestedScrollAxes & SCROLL_AXIS_VERTICAL) != 0; + } + + /** + * @inheritDoc + */ + @Override + public void onStopNestedScroll(View target) { + super.onStopNestedScroll(target); + } + + @Override + public void onNestedScroll(View target, int dxConsumed, int dyConsumed, + int dxUnconsumed, int dyUnconsumed) { + scrollBy(0, dyUnconsumed); + } + + /** + * @inheritDoc + */ + @Override + public boolean onNestedFling(View target, float velocityX, float velocityY) { + flingWithNestedDispatch((int) velocityY); + return true; + } + + @Override public void draw(Canvas canvas) { super.draw(canvas); if (mEdgeGlowTop != null) { |