| /* |
| * Copyright (C) 2007 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.view; |
| |
| import android.graphics.Rect; |
| import android.util.ArrayMap; |
| import android.util.SparseArray; |
| import android.util.SparseBooleanArray; |
| |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.Comparator; |
| |
| /** |
| * The algorithm used for finding the next focusable view in a given direction |
| * from a view that currently has focus. |
| */ |
| public class FocusFinder { |
| |
| private static final ThreadLocal<FocusFinder> tlFocusFinder = |
| new ThreadLocal<FocusFinder>() { |
| @Override |
| protected FocusFinder initialValue() { |
| return new FocusFinder(); |
| } |
| }; |
| |
| /** |
| * Get the focus finder for this thread. |
| */ |
| public static FocusFinder getInstance() { |
| return tlFocusFinder.get(); |
| } |
| |
| final Rect mFocusedRect = new Rect(); |
| final Rect mOtherRect = new Rect(); |
| final Rect mBestCandidateRect = new Rect(); |
| final SequentialFocusComparator mSequentialFocusComparator = new SequentialFocusComparator(); |
| |
| private final ArrayList<View> mTempList = new ArrayList<View>(); |
| |
| // enforce thread local access |
| private FocusFinder() {} |
| |
| /** |
| * Find the next view to take focus in root's descendants, starting from the view |
| * that currently is focused. |
| * @param root Contains focused. Cannot be null. |
| * @param focused Has focus now. |
| * @param direction Direction to look. |
| * @return The next focusable view, or null if none exists. |
| */ |
| public final View findNextFocus(ViewGroup root, View focused, int direction) { |
| return findNextFocus(root, focused, null, direction); |
| } |
| |
| /** |
| * Find the next view to take focus in root's descendants, searching from |
| * a particular rectangle in root's coordinates. |
| * @param root Contains focusedRect. Cannot be null. |
| * @param focusedRect The starting point of the search. |
| * @param direction Direction to look. |
| * @return The next focusable view, or null if none exists. |
| */ |
| public View findNextFocusFromRect(ViewGroup root, Rect focusedRect, int direction) { |
| mFocusedRect.set(focusedRect); |
| return findNextFocus(root, null, mFocusedRect, direction); |
| } |
| |
| private View findNextFocus(ViewGroup root, View focused, Rect focusedRect, int direction) { |
| View next = null; |
| if (focused != null) { |
| next = findNextUserSpecifiedFocus(root, focused, direction); |
| } |
| if (next != null) { |
| return next; |
| } |
| ArrayList<View> focusables = mTempList; |
| try { |
| focusables.clear(); |
| root.addFocusables(focusables, direction); |
| if (!focusables.isEmpty()) { |
| next = findNextFocus(root, focused, focusedRect, direction, focusables); |
| } |
| } finally { |
| focusables.clear(); |
| } |
| return next; |
| } |
| |
| private View findNextUserSpecifiedFocus(ViewGroup root, View focused, int direction) { |
| // check for user specified next focus |
| View userSetNextFocus = focused.findUserSetNextFocus(root, direction); |
| if (userSetNextFocus != null && userSetNextFocus.isFocusable() |
| && (!userSetNextFocus.isInTouchMode() |
| || userSetNextFocus.isFocusableInTouchMode())) { |
| return userSetNextFocus; |
| } |
| return null; |
| } |
| |
| private View findNextFocus(ViewGroup root, View focused, Rect focusedRect, |
| int direction, ArrayList<View> focusables) { |
| if (focused != null) { |
| if (focusedRect == null) { |
| focusedRect = mFocusedRect; |
| } |
| // fill in interesting rect from focused |
| focused.getFocusedRect(focusedRect); |
| root.offsetDescendantRectToMyCoords(focused, focusedRect); |
| } else { |
| if (focusedRect == null) { |
| focusedRect = mFocusedRect; |
| // make up a rect at top left or bottom right of root |
| switch (direction) { |
| case View.FOCUS_RIGHT: |
| case View.FOCUS_DOWN: |
| setFocusTopLeft(root, focusedRect); |
| break; |
| case View.FOCUS_FORWARD: |
| if (root.isLayoutRtl()) { |
| setFocusBottomRight(root, focusedRect); |
| } else { |
| setFocusTopLeft(root, focusedRect); |
| } |
| break; |
| |
| case View.FOCUS_LEFT: |
| case View.FOCUS_UP: |
| setFocusBottomRight(root, focusedRect); |
| break; |
| case View.FOCUS_BACKWARD: |
| if (root.isLayoutRtl()) { |
| setFocusTopLeft(root, focusedRect); |
| } else { |
| setFocusBottomRight(root, focusedRect); |
| break; |
| } |
| } |
| } |
| } |
| |
| switch (direction) { |
| case View.FOCUS_FORWARD: |
| case View.FOCUS_BACKWARD: |
| return findNextFocusInRelativeDirection(focusables, root, focused, focusedRect, |
| direction); |
| case View.FOCUS_UP: |
| case View.FOCUS_DOWN: |
| case View.FOCUS_LEFT: |
| case View.FOCUS_RIGHT: |
| return findNextFocusInAbsoluteDirection(focusables, root, focused, |
| focusedRect, direction); |
| default: |
| throw new IllegalArgumentException("Unknown direction: " + direction); |
| } |
| } |
| |
| private View findNextFocusInRelativeDirection(ArrayList<View> focusables, ViewGroup root, |
| View focused, Rect focusedRect, int direction) { |
| try { |
| // Note: This sort is stable. |
| mSequentialFocusComparator.setRoot(root); |
| mSequentialFocusComparator.setIsLayoutRtl(root.isLayoutRtl()); |
| mSequentialFocusComparator.setFocusables(focusables); |
| Collections.sort(focusables, mSequentialFocusComparator); |
| } finally { |
| mSequentialFocusComparator.recycle(); |
| } |
| |
| final int count = focusables.size(); |
| switch (direction) { |
| case View.FOCUS_FORWARD: |
| return getNextFocusable(focused, focusables, count); |
| case View.FOCUS_BACKWARD: |
| return getPreviousFocusable(focused, focusables, count); |
| } |
| return focusables.get(count - 1); |
| } |
| |
| private void setFocusBottomRight(ViewGroup root, Rect focusedRect) { |
| final int rootBottom = root.getScrollY() + root.getHeight(); |
| final int rootRight = root.getScrollX() + root.getWidth(); |
| focusedRect.set(rootRight, rootBottom, rootRight, rootBottom); |
| } |
| |
| private void setFocusTopLeft(ViewGroup root, Rect focusedRect) { |
| final int rootTop = root.getScrollY(); |
| final int rootLeft = root.getScrollX(); |
| focusedRect.set(rootLeft, rootTop, rootLeft, rootTop); |
| } |
| |
| View findNextFocusInAbsoluteDirection(ArrayList<View> focusables, ViewGroup root, View focused, |
| Rect focusedRect, int direction) { |
| // initialize the best candidate to something impossible |
| // (so the first plausible view will become the best choice) |
| mBestCandidateRect.set(focusedRect); |
| switch(direction) { |
| case View.FOCUS_LEFT: |
| mBestCandidateRect.offset(focusedRect.width() + 1, 0); |
| break; |
| case View.FOCUS_RIGHT: |
| mBestCandidateRect.offset(-(focusedRect.width() + 1), 0); |
| break; |
| case View.FOCUS_UP: |
| mBestCandidateRect.offset(0, focusedRect.height() + 1); |
| break; |
| case View.FOCUS_DOWN: |
| mBestCandidateRect.offset(0, -(focusedRect.height() + 1)); |
| } |
| |
| View closest = null; |
| |
| int numFocusables = focusables.size(); |
| for (int i = 0; i < numFocusables; i++) { |
| View focusable = focusables.get(i); |
| |
| // only interested in other non-root views |
| if (focusable == focused || focusable == root) continue; |
| |
| // get focus bounds of other view in same coordinate system |
| focusable.getFocusedRect(mOtherRect); |
| root.offsetDescendantRectToMyCoords(focusable, mOtherRect); |
| |
| if (isBetterCandidate(direction, focusedRect, mOtherRect, mBestCandidateRect)) { |
| mBestCandidateRect.set(mOtherRect); |
| closest = focusable; |
| } |
| } |
| return closest; |
| } |
| |
| private static View getNextFocusable(View focused, ArrayList<View> focusables, int count) { |
| if (focused != null) { |
| int position = focusables.lastIndexOf(focused); |
| if (position >= 0 && position + 1 < count) { |
| return focusables.get(position + 1); |
| } |
| } |
| if (!focusables.isEmpty()) { |
| return focusables.get(0); |
| } |
| return null; |
| } |
| |
| private static View getPreviousFocusable(View focused, ArrayList<View> focusables, int count) { |
| if (focused != null) { |
| int position = focusables.indexOf(focused); |
| if (position > 0) { |
| return focusables.get(position - 1); |
| } |
| } |
| if (!focusables.isEmpty()) { |
| return focusables.get(count - 1); |
| } |
| return null; |
| } |
| |
| /** |
| * Is rect1 a better candidate than rect2 for a focus search in a particular |
| * direction from a source rect? This is the core routine that determines |
| * the order of focus searching. |
| * @param direction the direction (up, down, left, right) |
| * @param source The source we are searching from |
| * @param rect1 The candidate rectangle |
| * @param rect2 The current best candidate. |
| * @return Whether the candidate is the new best. |
| */ |
| boolean isBetterCandidate(int direction, Rect source, Rect rect1, Rect rect2) { |
| |
| // to be a better candidate, need to at least be a candidate in the first |
| // place :) |
| if (!isCandidate(source, rect1, direction)) { |
| return false; |
| } |
| |
| // we know that rect1 is a candidate.. if rect2 is not a candidate, |
| // rect1 is better |
| if (!isCandidate(source, rect2, direction)) { |
| return true; |
| } |
| |
| // if rect1 is better by beam, it wins |
| if (beamBeats(direction, source, rect1, rect2)) { |
| return true; |
| } |
| |
| // if rect2 is better, then rect1 cant' be :) |
| if (beamBeats(direction, source, rect2, rect1)) { |
| return false; |
| } |
| |
| // otherwise, do fudge-tastic comparison of the major and minor axis |
| return (getWeightedDistanceFor( |
| majorAxisDistance(direction, source, rect1), |
| minorAxisDistance(direction, source, rect1)) |
| < getWeightedDistanceFor( |
| majorAxisDistance(direction, source, rect2), |
| minorAxisDistance(direction, source, rect2))); |
| } |
| |
| /** |
| * One rectangle may be another candidate than another by virtue of being |
| * exclusively in the beam of the source rect. |
| * @return Whether rect1 is a better candidate than rect2 by virtue of it being in src's |
| * beam |
| */ |
| boolean beamBeats(int direction, Rect source, Rect rect1, Rect rect2) { |
| final boolean rect1InSrcBeam = beamsOverlap(direction, source, rect1); |
| final boolean rect2InSrcBeam = beamsOverlap(direction, source, rect2); |
| |
| // if rect1 isn't exclusively in the src beam, it doesn't win |
| if (rect2InSrcBeam || !rect1InSrcBeam) { |
| return false; |
| } |
| |
| // we know rect1 is in the beam, and rect2 is not |
| |
| // if rect1 is to the direction of, and rect2 is not, rect1 wins. |
| // for example, for direction left, if rect1 is to the left of the source |
| // and rect2 is below, then we always prefer the in beam rect1, since rect2 |
| // could be reached by going down. |
| if (!isToDirectionOf(direction, source, rect2)) { |
| return true; |
| } |
| |
| // for horizontal directions, being exclusively in beam always wins |
| if ((direction == View.FOCUS_LEFT || direction == View.FOCUS_RIGHT)) { |
| return true; |
| } |
| |
| // for vertical directions, beams only beat up to a point: |
| // now, as long as rect2 isn't completely closer, rect1 wins |
| // e.g for direction down, completely closer means for rect2's top |
| // edge to be closer to the source's top edge than rect1's bottom edge. |
| return (majorAxisDistance(direction, source, rect1) |
| < majorAxisDistanceToFarEdge(direction, source, rect2)); |
| } |
| |
| /** |
| * Fudge-factor opportunity: how to calculate distance given major and minor |
| * axis distances. Warning: this fudge factor is finely tuned, be sure to |
| * run all focus tests if you dare tweak it. |
| */ |
| int getWeightedDistanceFor(int majorAxisDistance, int minorAxisDistance) { |
| return 13 * majorAxisDistance * majorAxisDistance |
| + minorAxisDistance * minorAxisDistance; |
| } |
| |
| /** |
| * Is destRect a candidate for the next focus given the direction? This |
| * checks whether the dest is at least partially to the direction of (e.g left of) |
| * from source. |
| * |
| * Includes an edge case for an empty rect (which is used in some cases when |
| * searching from a point on the screen). |
| */ |
| boolean isCandidate(Rect srcRect, Rect destRect, int direction) { |
| switch (direction) { |
| case View.FOCUS_LEFT: |
| return (srcRect.right > destRect.right || srcRect.left >= destRect.right) |
| && srcRect.left > destRect.left; |
| case View.FOCUS_RIGHT: |
| return (srcRect.left < destRect.left || srcRect.right <= destRect.left) |
| && srcRect.right < destRect.right; |
| case View.FOCUS_UP: |
| return (srcRect.bottom > destRect.bottom || srcRect.top >= destRect.bottom) |
| && srcRect.top > destRect.top; |
| case View.FOCUS_DOWN: |
| return (srcRect.top < destRect.top || srcRect.bottom <= destRect.top) |
| && srcRect.bottom < destRect.bottom; |
| } |
| throw new IllegalArgumentException("direction must be one of " |
| + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT}."); |
| } |
| |
| |
| /** |
| * Do the "beams" w.r.t the given direction's axis of rect1 and rect2 overlap? |
| * @param direction the direction (up, down, left, right) |
| * @param rect1 The first rectangle |
| * @param rect2 The second rectangle |
| * @return whether the beams overlap |
| */ |
| boolean beamsOverlap(int direction, Rect rect1, Rect rect2) { |
| switch (direction) { |
| case View.FOCUS_LEFT: |
| case View.FOCUS_RIGHT: |
| return (rect2.bottom >= rect1.top) && (rect2.top <= rect1.bottom); |
| case View.FOCUS_UP: |
| case View.FOCUS_DOWN: |
| return (rect2.right >= rect1.left) && (rect2.left <= rect1.right); |
| } |
| throw new IllegalArgumentException("direction must be one of " |
| + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT}."); |
| } |
| |
| /** |
| * e.g for left, is 'to left of' |
| */ |
| boolean isToDirectionOf(int direction, Rect src, Rect dest) { |
| switch (direction) { |
| case View.FOCUS_LEFT: |
| return src.left >= dest.right; |
| case View.FOCUS_RIGHT: |
| return src.right <= dest.left; |
| case View.FOCUS_UP: |
| return src.top >= dest.bottom; |
| case View.FOCUS_DOWN: |
| return src.bottom <= dest.top; |
| } |
| throw new IllegalArgumentException("direction must be one of " |
| + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT}."); |
| } |
| |
| /** |
| * @return The distance from the edge furthest in the given direction |
| * of source to the edge nearest in the given direction of dest. If the |
| * dest is not in the direction from source, return 0. |
| */ |
| static int majorAxisDistance(int direction, Rect source, Rect dest) { |
| return Math.max(0, majorAxisDistanceRaw(direction, source, dest)); |
| } |
| |
| static int majorAxisDistanceRaw(int direction, Rect source, Rect dest) { |
| switch (direction) { |
| case View.FOCUS_LEFT: |
| return source.left - dest.right; |
| case View.FOCUS_RIGHT: |
| return dest.left - source.right; |
| case View.FOCUS_UP: |
| return source.top - dest.bottom; |
| case View.FOCUS_DOWN: |
| return dest.top - source.bottom; |
| } |
| throw new IllegalArgumentException("direction must be one of " |
| + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT}."); |
| } |
| |
| /** |
| * @return The distance along the major axis w.r.t the direction from the |
| * edge of source to the far edge of dest. If the |
| * dest is not in the direction from source, return 1 (to break ties with |
| * {@link #majorAxisDistance}). |
| */ |
| static int majorAxisDistanceToFarEdge(int direction, Rect source, Rect dest) { |
| return Math.max(1, majorAxisDistanceToFarEdgeRaw(direction, source, dest)); |
| } |
| |
| static int majorAxisDistanceToFarEdgeRaw(int direction, Rect source, Rect dest) { |
| switch (direction) { |
| case View.FOCUS_LEFT: |
| return source.left - dest.left; |
| case View.FOCUS_RIGHT: |
| return dest.right - source.right; |
| case View.FOCUS_UP: |
| return source.top - dest.top; |
| case View.FOCUS_DOWN: |
| return dest.bottom - source.bottom; |
| } |
| throw new IllegalArgumentException("direction must be one of " |
| + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT}."); |
| } |
| |
| /** |
| * Find the distance on the minor axis w.r.t the direction to the nearest |
| * edge of the destination rectangle. |
| * @param direction the direction (up, down, left, right) |
| * @param source The source rect. |
| * @param dest The destination rect. |
| * @return The distance. |
| */ |
| static int minorAxisDistance(int direction, Rect source, Rect dest) { |
| switch (direction) { |
| case View.FOCUS_LEFT: |
| case View.FOCUS_RIGHT: |
| // the distance between the center verticals |
| return Math.abs( |
| ((source.top + source.height() / 2) - |
| ((dest.top + dest.height() / 2)))); |
| case View.FOCUS_UP: |
| case View.FOCUS_DOWN: |
| // the distance between the center horizontals |
| return Math.abs( |
| ((source.left + source.width() / 2) - |
| ((dest.left + dest.width() / 2)))); |
| } |
| throw new IllegalArgumentException("direction must be one of " |
| + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT}."); |
| } |
| |
| /** |
| * Find the nearest touchable view to the specified view. |
| * |
| * @param root The root of the tree in which to search |
| * @param x X coordinate from which to start the search |
| * @param y Y coordinate from which to start the search |
| * @param direction Direction to look |
| * @param deltas Offset from the <x, y> to the edge of the nearest view. Note that this array |
| * may already be populated with values. |
| * @return The nearest touchable view, or null if none exists. |
| */ |
| public View findNearestTouchable(ViewGroup root, int x, int y, int direction, int[] deltas) { |
| ArrayList<View> touchables = root.getTouchables(); |
| int minDistance = Integer.MAX_VALUE; |
| View closest = null; |
| |
| int numTouchables = touchables.size(); |
| |
| int edgeSlop = ViewConfiguration.get(root.mContext).getScaledEdgeSlop(); |
| |
| Rect closestBounds = new Rect(); |
| Rect touchableBounds = mOtherRect; |
| |
| for (int i = 0; i < numTouchables; i++) { |
| View touchable = touchables.get(i); |
| |
| // get visible bounds of other view in same coordinate system |
| touchable.getDrawingRect(touchableBounds); |
| |
| root.offsetRectBetweenParentAndChild(touchable, touchableBounds, true, true); |
| |
| if (!isTouchCandidate(x, y, touchableBounds, direction)) { |
| continue; |
| } |
| |
| int distance = Integer.MAX_VALUE; |
| |
| switch (direction) { |
| case View.FOCUS_LEFT: |
| distance = x - touchableBounds.right + 1; |
| break; |
| case View.FOCUS_RIGHT: |
| distance = touchableBounds.left; |
| break; |
| case View.FOCUS_UP: |
| distance = y - touchableBounds.bottom + 1; |
| break; |
| case View.FOCUS_DOWN: |
| distance = touchableBounds.top; |
| break; |
| } |
| |
| if (distance < edgeSlop) { |
| // Give preference to innermost views |
| if (closest == null || |
| closestBounds.contains(touchableBounds) || |
| (!touchableBounds.contains(closestBounds) && distance < minDistance)) { |
| minDistance = distance; |
| closest = touchable; |
| closestBounds.set(touchableBounds); |
| switch (direction) { |
| case View.FOCUS_LEFT: |
| deltas[0] = -distance; |
| break; |
| case View.FOCUS_RIGHT: |
| deltas[0] = distance; |
| break; |
| case View.FOCUS_UP: |
| deltas[1] = -distance; |
| break; |
| case View.FOCUS_DOWN: |
| deltas[1] = distance; |
| break; |
| } |
| } |
| } |
| } |
| return closest; |
| } |
| |
| |
| /** |
| * Is destRect a candidate for the next touch given the direction? |
| */ |
| private boolean isTouchCandidate(int x, int y, Rect destRect, int direction) { |
| switch (direction) { |
| case View.FOCUS_LEFT: |
| return destRect.left <= x && destRect.top <= y && y <= destRect.bottom; |
| case View.FOCUS_RIGHT: |
| return destRect.left >= x && destRect.top <= y && y <= destRect.bottom; |
| case View.FOCUS_UP: |
| return destRect.top <= y && destRect.left <= x && x <= destRect.right; |
| case View.FOCUS_DOWN: |
| return destRect.top >= y && destRect.left <= x && x <= destRect.right; |
| } |
| throw new IllegalArgumentException("direction must be one of " |
| + "{FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, FOCUS_RIGHT}."); |
| } |
| |
| private static final boolean isValidId(final int id) { |
| return id != 0 && id != View.NO_ID; |
| } |
| |
| /** |
| * Sorts views according to their visual layout and geometry for default tab order. |
| * If views are part of a focus chain (nextFocusForwardId), then they are all grouped |
| * together. The head of the chain is used to determine the order of the chain and is |
| * first in the order and the tail of the chain is the last in the order. The views |
| * in the middle of the chain can be arbitrary order. |
| * This is used for sequential focus traversal. |
| */ |
| private static final class SequentialFocusComparator implements Comparator<View> { |
| private final Rect mFirstRect = new Rect(); |
| private final Rect mSecondRect = new Rect(); |
| private ViewGroup mRoot; |
| private boolean mIsLayoutRtl; |
| private final SparseArray<View> mFocusables = new SparseArray<View>(); |
| private final SparseBooleanArray mIsConnectedTo = new SparseBooleanArray(); |
| private final ArrayMap<View, View> mHeadsOfChains = new ArrayMap<View, View>(); |
| |
| public void recycle() { |
| mRoot = null; |
| mFocusables.clear(); |
| mHeadsOfChains.clear(); |
| mIsConnectedTo.clear(); |
| } |
| |
| public void setRoot(ViewGroup root) { |
| mRoot = root; |
| } |
| |
| public void setIsLayoutRtl(boolean b) { |
| mIsLayoutRtl = b; |
| } |
| |
| public void setFocusables(ArrayList<View> focusables) { |
| for (int i = focusables.size() - 1; i >= 0; i--) { |
| final View view = focusables.get(i); |
| final int id = view.getId(); |
| if (isValidId(id)) { |
| mFocusables.put(id, view); |
| } |
| final int nextId = view.getNextFocusForwardId(); |
| if (isValidId(nextId)) { |
| mIsConnectedTo.put(nextId, true); |
| } |
| } |
| |
| for (int i = focusables.size() - 1; i >= 0; i--) { |
| final View view = focusables.get(i); |
| final int nextId = view.getNextFocusForwardId(); |
| if (isValidId(nextId) && !mIsConnectedTo.get(view.getId())) { |
| setHeadOfChain(view); |
| } |
| } |
| } |
| |
| private void setHeadOfChain(View head) { |
| for (View view = head; view != null; |
| view = mFocusables.get(view.getNextFocusForwardId())) { |
| final View otherHead = mHeadsOfChains.get(view); |
| if (otherHead != null) { |
| if (otherHead == head) { |
| return; // This view has already had its head set properly |
| } |
| // A hydra -- multi-headed focus chain (e.g. A->C and B->C) |
| // Use the one we've already chosen instead and reset this chain. |
| view = head; |
| head = otherHead; |
| } |
| mHeadsOfChains.put(view, head); |
| } |
| } |
| |
| public int compare(View first, View second) { |
| if (first == second) { |
| return 0; |
| } |
| // Order between views within a chain is immaterial -- next/previous is |
| // within a chain is handled elsewhere. |
| View firstHead = mHeadsOfChains.get(first); |
| View secondHead = mHeadsOfChains.get(second); |
| if (firstHead == secondHead && firstHead != null) { |
| if (first == firstHead) { |
| return -1; // first is the head, it should be first |
| } else if (second == firstHead) { |
| return 1; // second is the head, it should be first |
| } else if (isValidId(first.getNextFocusForwardId())) { |
| return -1; // first is not the end of the chain |
| } else { |
| return 1; // first is end of chain |
| } |
| } |
| if (firstHead != null) { |
| first = firstHead; |
| } |
| if (secondHead != null) { |
| second = secondHead; |
| } |
| |
| // First see if they belong to the same focus chain. |
| getRect(first, mFirstRect); |
| getRect(second, mSecondRect); |
| |
| if (mFirstRect.top < mSecondRect.top) { |
| return -1; |
| } else if (mFirstRect.top > mSecondRect.top) { |
| return 1; |
| } else if (mFirstRect.left < mSecondRect.left) { |
| return mIsLayoutRtl ? 1 : -1; |
| } else if (mFirstRect.left > mSecondRect.left) { |
| return mIsLayoutRtl ? -1 : 1; |
| } else if (mFirstRect.bottom < mSecondRect.bottom) { |
| return -1; |
| } else if (mFirstRect.bottom > mSecondRect.bottom) { |
| return 1; |
| } else if (mFirstRect.right < mSecondRect.right) { |
| return mIsLayoutRtl ? 1 : -1; |
| } else if (mFirstRect.right > mSecondRect.right) { |
| return mIsLayoutRtl ? -1 : 1; |
| } else { |
| // The view are distinct but completely coincident so we consider |
| // them equal for our purposes. Since the sort is stable, this |
| // means that the views will retain their layout order relative to one another. |
| return 0; |
| } |
| } |
| |
| private void getRect(View view, Rect rect) { |
| view.getDrawingRect(rect); |
| mRoot.offsetDescendantRectToMyCoords(view, rect); |
| } |
| } |
| } |
