From 00481b3ed322b4f36b669201d2287964febda65f Mon Sep 17 00:00:00 2001 From: Adam Cohen Date: Fri, 18 Nov 2011 12:03:48 -0800 Subject: Fixing PagedView bad snap-back decisions -> There was some code that was causing pages to snap back much to the original page much too frequently. Change-Id: Ibd02ac634c737887a2bcfd7096882c95c51087f1 --- src/com/android/launcher2/PagedView.java | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) (limited to 'src') diff --git a/src/com/android/launcher2/PagedView.java b/src/com/android/launcher2/PagedView.java index 935d26df9..f08072142 100644 --- a/src/com/android/launcher2/PagedView.java +++ b/src/com/android/launcher2/PagedView.java @@ -61,8 +61,6 @@ public abstract class PagedView extends ViewGroup { // the min drag distance for a fling to register, to prevent random page shifts private static final int MIN_LENGTH_FOR_FLING = 25; - // The min drag distance to trigger a page shift (regardless of velocity) - private static final int MIN_LENGTH_FOR_MOVE = 200; private static final int PAGE_SNAP_ANIMATION_DURATION = 550; protected static final float NANOTIME_DIV = 1000000000.0f; @@ -72,6 +70,8 @@ public abstract class PagedView extends ViewGroup { private static final int MINIMUM_SNAP_VELOCITY = 2200; private static final int MIN_FLING_VELOCITY = 250; private static final float RETURN_TO_ORIGINAL_PAGE_THRESHOLD = 0.33f; + // The page is moved more than halfway, automatically move to the next page on touch up. + private static final float SIGNIFICANT_MOVE_THRESHOLD = 0.4f; // the velocity at which a fling gesture will cause us to snap to the next page protected int mSnapVelocity = 500; @@ -1205,24 +1205,25 @@ public abstract class PagedView extends ViewGroup { velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); int velocityX = (int) velocityTracker.getXVelocity(activePointerId); final int deltaX = (int) (x - mDownMotionX); - boolean isSignificantMove = Math.abs(deltaX) > MIN_LENGTH_FOR_MOVE; + final int pageWidth = getScaledMeasuredWidth(getPageAt(mCurrentPage)); + boolean isSignificantMove = Math.abs(deltaX) > pageWidth * + SIGNIFICANT_MOVE_THRESHOLD; final int snapVelocity = mSnapVelocity; mTotalMotionX += Math.abs(mLastMotionX + mLastMotionXRemainder - x); + boolean isFling = mTotalMotionX > MIN_LENGTH_FOR_FLING && + Math.abs(velocityX) > snapVelocity; + // In the case that the page is moved far to one direction and then is flung // in the opposite direction, we use a threshold to determine whether we should // just return to the starting page, or if we should skip one further. boolean returnToOriginalPage = false; - final int pageWidth = getScaledMeasuredWidth(getPageAt(mCurrentPage)); if (Math.abs(deltaX) > pageWidth * RETURN_TO_ORIGINAL_PAGE_THRESHOLD && - Math.signum(velocityX) != Math.signum(deltaX)) { + Math.signum(velocityX) != Math.signum(deltaX) && isFling) { returnToOriginalPage = true; } - boolean isFling = mTotalMotionX > MIN_LENGTH_FOR_FLING && - Math.abs(velocityX) > snapVelocity; - int finalPage; // We give flings precedence over large moves, which is why we short-circuit our // test for a large move if a fling has been registered. That is, a large -- cgit v1.2.3