public void setCurrentItemInternal(int item, boolean smoothScroll, boolean always, int velocity) { if (!always && mCurItem == item) { setScrollingCacheEnabled(false); return; } item = mViewBehind.getMenuPage(item); final boolean dispatchSelected = mCurItem != item; mCurItem = item; if (mViewBehind.getbMode()) { final int destY = getDestScrollX(mCurItem); if (dispatchSelected && mOnPageChangeListener != null) { mOnPageChangeListener.onPageSelected(item); } if (dispatchSelected && mInternalPageChangeListener != null) { mInternalPageChangeListener.onPageSelected(item); } if (smoothScroll) { smoothScrollTo(0, destY, velocity); } else { completeScroll(); scrollTo(0, destY); } } else { final int destX = getDestScrollX(mCurItem); if (dispatchSelected && mOnPageChangeListener != null) { mOnPageChangeListener.onPageSelected(item); } if (dispatchSelected && mInternalPageChangeListener != null) { mInternalPageChangeListener.onPageSelected(item); } if (smoothScroll) { smoothScrollTo(destX, 0, velocity); } else { completeScroll(); scrollTo(destX, 0); } } }
@Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); // Make sure scroll position is set correctly. if (w != oldw) { // [ChrisJ] - This fixes the onConfiguration change for orientation issue.. // maybe worth having a look why the recomputeScroll pos is screwing // up? completeScroll(); scrollTo(getDestScrollX(mCurItem), getScrollY()); } }
/** * Like {@link View#scrollBy}, but scroll smoothly instead of immediately. * * @param x the number of pixels to scroll by on the X axis * @param y the number of pixels to scroll by on the Y axis * @param velocity the velocity associated with a fling, if applicable. (0 otherwise) */ void smoothScrollTo(int x, int y, int velocity) { if (getChildCount() == 0) { // Nothing to do. setScrollingCacheEnabled(false); return; } int sx = getScrollX(); int sy = getScrollY(); int dx = x - sx; int dy = y - sy; if (dx == 0 && dy == 0) { completeScroll(); if (isMenuOpen()) { if (mOpenedListener != null) mOpenedListener.onOpened(); } else { if (mClosedListener != null) mClosedListener.onClosed(); } return; } setScrollingCacheEnabled(true); mScrolling = true; final int width = getBehindWidth(); final int halfWidth = width / 2; final float distanceRatio = Math.min(1f, 1.0f * Math.abs(dx) / width); final float distance = halfWidth + halfWidth * distanceInfluenceForSnapDuration(distanceRatio); int duration = 0; velocity = Math.abs(velocity); if (velocity > 0) { duration = 4 * Math.round(1000 * Math.abs(distance / velocity)); } else { final float pageDelta = (float) Math.abs(dx) / width; duration = (int) ((pageDelta + 1) * 100); duration = MAX_SETTLE_DURATION; } duration = Math.min(duration, MAX_SETTLE_DURATION); mScroller.startScroll(sx, sy, dx, dy, duration); invalidate(); }
@Override public void computeScroll() { if (!mScroller.isFinished()) { if (mScroller.computeScrollOffset()) { int oldX = getScrollX(); int oldY = getScrollY(); int x = mScroller.getCurrX(); int y = mScroller.getCurrY(); if (oldX != x || oldY != y) { scrollTo(x, y); pageScrolled(x); } // Keep on drawing until the animation has finished. invalidate(); return; } } // Done with scroll, clean up state. completeScroll(); }
@Override public boolean onTouchEvent(MotionEvent ev) { if (!mEnabled) return false; if (!mIsBeingDragged && !thisTouchAllowed(ev)) return false; // if (!mIsBeingDragged && !mQuickReturn) // return false; final int action = ev.getAction(); if (mVelocityTracker == null) { mVelocityTracker = VelocityTracker.obtain(); } mVelocityTracker.addMovement(ev); switch (action & MotionEventCompat.ACTION_MASK) { case MotionEvent.ACTION_DOWN: /* * If being flinged and user touches, stop the fling. isFinished * will be false if being flinged. */ completeScroll(); // Remember where the motion event started int index = MotionEventCompat.getActionIndex(ev); mActivePointerId = MotionEventCompat.getPointerId(ev, index); mLastMotionX = mInitialMotionX = ev.getX(); break; case MotionEvent.ACTION_MOVE: if (!mIsBeingDragged) { determineDrag(ev); if (mIsUnableToDrag) return false; } if (mIsBeingDragged) { // Scroll to follow the motion event final int activePointerIndex = getPointerIndex(ev, mActivePointerId); if (mActivePointerId == INVALID_POINTER) break; final float x = MotionEventCompat.getX(ev, activePointerIndex); final float deltaX = mLastMotionX - x; mLastMotionX = x; float oldScrollX = getScrollX(); float scrollX = oldScrollX + deltaX; final float leftBound = getLeftBound(); final float rightBound = getRightBound(); if (scrollX < leftBound) { scrollX = leftBound; } else if (scrollX > rightBound) { scrollX = rightBound; } // Don't lose the rounded component mLastMotionX += scrollX - (int) scrollX; scrollTo((int) scrollX, getScrollY()); pageScrolled((int) scrollX); } break; case MotionEvent.ACTION_UP: if (mIsBeingDragged) { final VelocityTracker velocityTracker = mVelocityTracker; velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); int initialVelocity = (int) VelocityTrackerCompat.getXVelocity(velocityTracker, mActivePointerId); final int scrollX = getScrollX(); final float pageOffset = (float) (scrollX - getDestScrollX(mCurItem)) / getBehindWidth(); final int activePointerIndex = getPointerIndex(ev, mActivePointerId); if (mActivePointerId != INVALID_POINTER) { final float x = MotionEventCompat.getX(ev, activePointerIndex); final int totalDelta = (int) (x - mInitialMotionX); int nextPage = determineTargetPage(pageOffset, initialVelocity, totalDelta); setCurrentItemInternal(nextPage, true, true, initialVelocity); } else { setCurrentItemInternal(mCurItem, true, true, initialVelocity); } mActivePointerId = INVALID_POINTER; endDrag(); } else if (mQuickReturn && mViewBehind.menuTouchInQuickReturn(mContent, mCurItem, ev.getX() + mScrollX)) { // close the menu setCurrentItem(1); endDrag(); } break; case MotionEvent.ACTION_CANCEL: if (mIsBeingDragged) { setCurrentItemInternal(mCurItem, true, true); mActivePointerId = INVALID_POINTER; endDrag(); } break; case MotionEventCompat.ACTION_POINTER_DOWN: { final int indexx = MotionEventCompat.getActionIndex(ev); mLastMotionX = MotionEventCompat.getX(ev, indexx); mActivePointerId = MotionEventCompat.getPointerId(ev, indexx); break; } case MotionEventCompat.ACTION_POINTER_UP: onSecondaryPointerUp(ev); int pointerIndex = getPointerIndex(ev, mActivePointerId); if (mActivePointerId == INVALID_POINTER) break; mLastMotionX = MotionEventCompat.getX(ev, pointerIndex); break; } return true; }