GridLayoutManager.java revision ef4e1b371215f9fffa9245159250740b611dfb4d
1/* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except 5 * in compliance with the License. You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software distributed under the License 10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express 11 * or implied. See the License for the specific language governing permissions and limitations under 12 * the License. 13 */ 14package android.support.v17.leanback.widget; 15 16import android.content.Context; 17import android.graphics.PointF; 18import android.graphics.Rect; 19import android.os.Bundle; 20import android.os.Parcel; 21import android.os.Parcelable; 22import android.support.v4.util.CircularIntArray; 23import android.support.v4.view.ViewCompat; 24import android.support.v4.view.accessibility.AccessibilityNodeInfoCompat; 25import android.support.v7.widget.LinearSmoothScroller; 26import android.support.v7.widget.OrientationHelper; 27import android.support.v7.widget.RecyclerView; 28import android.support.v7.widget.RecyclerView.Recycler; 29import android.support.v7.widget.RecyclerView.State; 30import android.support.v17.leanback.os.TraceHelper; 31 32import static android.support.v7.widget.RecyclerView.NO_ID; 33import static android.support.v7.widget.RecyclerView.NO_POSITION; 34import static android.support.v7.widget.RecyclerView.HORIZONTAL; 35import static android.support.v7.widget.RecyclerView.VERTICAL; 36 37import android.util.AttributeSet; 38import android.util.Log; 39import android.view.FocusFinder; 40import android.view.Gravity; 41import android.view.View; 42import android.view.View.MeasureSpec; 43import android.view.ViewGroup.MarginLayoutParams; 44import android.view.ViewGroup; 45 46import java.io.PrintWriter; 47import java.io.StringWriter; 48import java.util.ArrayList; 49 50final class GridLayoutManager extends RecyclerView.LayoutManager { 51 52 /* 53 * LayoutParams for {@link HorizontalGridView} and {@link VerticalGridView}. 54 * The class currently does two internal jobs: 55 * - Saves optical bounds insets. 56 * - Caches focus align view center. 57 */ 58 final static class LayoutParams extends RecyclerView.LayoutParams { 59 60 // For placement 61 private int mLeftInset; 62 private int mTopInset; 63 private int mRightInset; 64 private int mBottomInset; 65 66 // For alignment 67 private int mAlignX; 68 private int mAlignY; 69 private int[] mAlignMultiple; 70 private ItemAlignmentFacet mAlignmentFacet; 71 72 public LayoutParams(Context c, AttributeSet attrs) { 73 super(c, attrs); 74 } 75 76 public LayoutParams(int width, int height) { 77 super(width, height); 78 } 79 80 public LayoutParams(MarginLayoutParams source) { 81 super(source); 82 } 83 84 public LayoutParams(ViewGroup.LayoutParams source) { 85 super(source); 86 } 87 88 public LayoutParams(RecyclerView.LayoutParams source) { 89 super(source); 90 } 91 92 public LayoutParams(LayoutParams source) { 93 super(source); 94 } 95 96 int getAlignX() { 97 return mAlignX; 98 } 99 100 int getAlignY() { 101 return mAlignY; 102 } 103 104 int getOpticalLeft(View view) { 105 return view.getLeft() + mLeftInset; 106 } 107 108 int getOpticalTop(View view) { 109 return view.getTop() + mTopInset; 110 } 111 112 int getOpticalRight(View view) { 113 return view.getRight() - mRightInset; 114 } 115 116 int getOpticalBottom(View view) { 117 return view.getBottom() - mBottomInset; 118 } 119 120 int getOpticalWidth(View view) { 121 return view.getWidth() - mLeftInset - mRightInset; 122 } 123 124 int getOpticalHeight(View view) { 125 return view.getHeight() - mTopInset - mBottomInset; 126 } 127 128 int getOpticalLeftInset() { 129 return mLeftInset; 130 } 131 132 int getOpticalRightInset() { 133 return mRightInset; 134 } 135 136 int getOpticalTopInset() { 137 return mTopInset; 138 } 139 140 int getOpticalBottomInset() { 141 return mBottomInset; 142 } 143 144 void setAlignX(int alignX) { 145 mAlignX = alignX; 146 } 147 148 void setAlignY(int alignY) { 149 mAlignY = alignY; 150 } 151 152 void setItemAlignmentFacet(ItemAlignmentFacet facet) { 153 mAlignmentFacet = facet; 154 } 155 156 ItemAlignmentFacet getItemAlignmentFacet() { 157 return mAlignmentFacet; 158 } 159 160 void calculateItemAlignments(int orientation, View view) { 161 ItemAlignmentFacet.ItemAlignmentDef[] defs = mAlignmentFacet.getAlignmentDefs(); 162 if (mAlignMultiple == null || mAlignMultiple.length != defs.length) { 163 mAlignMultiple = new int[defs.length]; 164 } 165 for (int i = 0; i < defs.length; i++) { 166 mAlignMultiple[i] = ItemAlignmentFacetHelper 167 .getAlignmentPosition(view, defs[i], orientation); 168 } 169 if (orientation == HORIZONTAL) { 170 mAlignX = mAlignMultiple[0]; 171 } else { 172 mAlignY = mAlignMultiple[0]; 173 } 174 } 175 176 int[] getAlignMultiple() { 177 return mAlignMultiple; 178 } 179 180 void setOpticalInsets(int leftInset, int topInset, int rightInset, int bottomInset) { 181 mLeftInset = leftInset; 182 mTopInset = topInset; 183 mRightInset = rightInset; 184 mBottomInset = bottomInset; 185 } 186 187 } 188 189 /** 190 * Base class which scrolls to selected view in onStop(). 191 */ 192 abstract class GridLinearSmoothScroller extends LinearSmoothScroller { 193 GridLinearSmoothScroller() { 194 super(mBaseGridView.getContext()); 195 } 196 197 @Override 198 protected void onStop() { 199 // onTargetFound() may not be called if we hit the "wall" first or get cancelled. 200 View targetView = findViewByPosition(getTargetPosition()); 201 if (targetView == null) { 202 if (getTargetPosition() >= 0) { 203 // if smooth scroller is stopped without target, immediately jumps 204 // to the target position. 205 scrollToSelection(getTargetPosition(), 0, false, 0); 206 } 207 super.onStop(); 208 return; 209 } 210 if (hasFocus()) { 211 mInSelection = true; 212 targetView.requestFocus(); 213 mInSelection = false; 214 } 215 dispatchChildSelected(); 216 super.onStop(); 217 } 218 219 @Override 220 protected int calculateTimeForScrolling(int dx) { 221 int ms = super.calculateTimeForScrolling(dx); 222 if (mWindowAlignment.mainAxis().getSize() > 0) { 223 float minMs = (float) MIN_MS_SMOOTH_SCROLL_MAIN_SCREEN / 224 mWindowAlignment.mainAxis().getSize() * dx; 225 if (ms < minMs) { 226 ms = (int) minMs; 227 } 228 } 229 return ms; 230 } 231 232 @Override 233 protected void onTargetFound(View targetView, 234 RecyclerView.State state, Action action) { 235 if (getScrollPosition(targetView, null, sTwoInts)) { 236 int dx, dy; 237 if (mOrientation == HORIZONTAL) { 238 dx = sTwoInts[0]; 239 dy = sTwoInts[1]; 240 } else { 241 dx = sTwoInts[1]; 242 dy = sTwoInts[0]; 243 } 244 final int distance = (int) Math.sqrt(dx * dx + dy * dy); 245 final int time = calculateTimeForDeceleration(distance); 246 action.update(dx, dy, time, mDecelerateInterpolator); 247 } 248 } 249 } 250 251 /** 252 * The SmoothScroller that remembers pending DPAD keys and consume pending keys 253 * during scroll. 254 */ 255 final class PendingMoveSmoothScroller extends GridLinearSmoothScroller { 256 // -2 is a target position that LinearSmoothScroller can never find until 257 // consumePendingMovesXXX() sets real targetPosition. 258 final static int TARGET_UNDEFINED = -2; 259 // whether the grid is staggered. 260 private final boolean mStaggeredGrid; 261 // Number of pending movements on primary direction, negative if PREV_ITEM. 262 private int mPendingMoves; 263 264 PendingMoveSmoothScroller(int initialPendingMoves, boolean staggeredGrid) { 265 mPendingMoves = initialPendingMoves; 266 mStaggeredGrid = staggeredGrid; 267 setTargetPosition(TARGET_UNDEFINED); 268 } 269 270 void increasePendingMoves() { 271 if (mPendingMoves < MAX_PENDING_MOVES) { 272 mPendingMoves++; 273 } 274 } 275 276 void decreasePendingMoves() { 277 if (mPendingMoves > -MAX_PENDING_MOVES) { 278 mPendingMoves--; 279 } 280 } 281 282 /** 283 * Called before laid out an item when non-staggered grid can handle pending movements 284 * by skipping "mNumRows" per movement; staggered grid will have to wait the item 285 * has been laid out in consumePendingMovesAfterLayout(). 286 */ 287 void consumePendingMovesBeforeLayout() { 288 if (mStaggeredGrid || mPendingMoves == 0) { 289 return; 290 } 291 View newSelected = null; 292 int startPos = mPendingMoves > 0 ? mFocusPosition + mNumRows : 293 mFocusPosition - mNumRows; 294 for (int pos = startPos; mPendingMoves != 0; 295 pos = mPendingMoves > 0 ? pos + mNumRows: pos - mNumRows) { 296 View v = findViewByPosition(pos); 297 if (v == null) { 298 break; 299 } 300 if (!canScrollTo(v)) { 301 continue; 302 } 303 newSelected = v; 304 mFocusPosition = pos; 305 mSubFocusPosition = 0; 306 if (mPendingMoves > 0) { 307 mPendingMoves--; 308 } else { 309 mPendingMoves++; 310 } 311 } 312 if (newSelected != null && hasFocus()) { 313 mInSelection = true; 314 newSelected.requestFocus(); 315 mInSelection = false; 316 } 317 } 318 319 /** 320 * Called after laid out an item. Staggered grid should find view on same 321 * Row and consume pending movements. 322 */ 323 void consumePendingMovesAfterLayout() { 324 if (mStaggeredGrid && mPendingMoves != 0) { 325 // consume pending moves, focus to item on the same row. 326 mPendingMoves = processSelectionMoves(true, mPendingMoves); 327 } 328 if (mPendingMoves == 0 || (mPendingMoves > 0 && hasCreatedLastItem()) 329 || (mPendingMoves < 0 && hasCreatedFirstItem())) { 330 setTargetPosition(mFocusPosition); 331 stop(); 332 } 333 } 334 335 @Override 336 protected void updateActionForInterimTarget(Action action) { 337 if (mPendingMoves == 0) { 338 return; 339 } 340 super.updateActionForInterimTarget(action); 341 } 342 343 @Override 344 public PointF computeScrollVectorForPosition(int targetPosition) { 345 if (mPendingMoves == 0) { 346 return null; 347 } 348 int direction = (mReverseFlowPrimary ? mPendingMoves > 0 : mPendingMoves < 0) ? 349 -1 : 1; 350 if (mOrientation == HORIZONTAL) { 351 return new PointF(direction, 0); 352 } else { 353 return new PointF(0, direction); 354 } 355 } 356 357 @Override 358 protected void onStop() { 359 super.onStop(); 360 // if we hit wall, need clear the remaining pending moves. 361 mPendingMoves = 0; 362 mPendingMoveSmoothScroller = null; 363 View v = findViewByPosition(getTargetPosition()); 364 if (v != null) scrollToView(v, true); 365 } 366 }; 367 368 private static final String TAG = "GridLayoutManager"; 369 private static final boolean DEBUG = false; 370 private static final boolean TRACE = false; 371 372 // maximum pending movement in one direction. 373 private final static int MAX_PENDING_MOVES = 10; 374 // minimal milliseconds to scroll window size in major direction, we put a cap to prevent the 375 // effect smooth scrolling too over to bind an item view then drag the item view back. 376 private final static int MIN_MS_SMOOTH_SCROLL_MAIN_SCREEN = 30; 377 378 private String getTag() { 379 return TAG + ":" + mBaseGridView.getId(); 380 } 381 382 private final BaseGridView mBaseGridView; 383 384 /** 385 * Note on conventions in the presence of RTL layout directions: 386 * Many properties and method names reference entities related to the 387 * beginnings and ends of things. In the presence of RTL flows, 388 * it may not be clear whether this is intended to reference a 389 * quantity that changes direction in RTL cases, or a quantity that 390 * does not. Here are the conventions in use: 391 * 392 * start/end: coordinate quantities - do reverse 393 * (optical) left/right: coordinate quantities - do not reverse 394 * low/high: coordinate quantities - do not reverse 395 * min/max: coordinate quantities - do not reverse 396 * scroll offset - coordinate quantities - do not reverse 397 * first/last: positional indices - do not reverse 398 * front/end: positional indices - do not reverse 399 * prepend/append: related to positional indices - do not reverse 400 * 401 * Note that although quantities do not reverse in RTL flows, their 402 * relationship does. In LTR flows, the first positional index is 403 * leftmost; in RTL flows, it is rightmost. Thus, anywhere that 404 * positional quantities are mapped onto coordinate quantities, 405 * the flow must be checked and the logic reversed. 406 */ 407 408 /** 409 * The orientation of a "row". 410 */ 411 private int mOrientation = HORIZONTAL; 412 private OrientationHelper mOrientationHelper = OrientationHelper.createHorizontalHelper(this); 413 414 private RecyclerView.State mState; 415 private RecyclerView.Recycler mRecycler; 416 417 private static final Rect sTempRect = new Rect(); 418 419 private boolean mInLayout; 420 private boolean mInScroll; 421 private boolean mInFastRelayout; 422 /** 423 * During full layout pass, when GridView had focus: onLayoutChildren will 424 * skip non-focusable child and adjust mFocusPosition. 425 */ 426 private boolean mInLayoutSearchFocus; 427 private boolean mInSelection = false; 428 429 private OnChildSelectedListener mChildSelectedListener = null; 430 431 private ArrayList<OnChildViewHolderSelectedListener> mChildViewHolderSelectedListeners = null; 432 433 private OnChildLaidOutListener mChildLaidOutListener = null; 434 435 /** 436 * The focused position, it's not the currently visually aligned position 437 * but it is the final position that we intend to focus on. If there are 438 * multiple setSelection() called, mFocusPosition saves last value. 439 */ 440 private int mFocusPosition = NO_POSITION; 441 442 /** 443 * A view can have multiple alignment position, this is the index of which 444 * alignment is used, by default is 0. 445 */ 446 private int mSubFocusPosition = 0; 447 448 /** 449 * LinearSmoothScroller that consume pending DPAD movements. 450 */ 451 private PendingMoveSmoothScroller mPendingMoveSmoothScroller; 452 453 /** 454 * The offset to be applied to mFocusPosition, due to adapter change, on the next 455 * layout. Set to Integer.MIN_VALUE means we should stop adding delta to mFocusPosition 456 * until next layout cycler. 457 * TODO: This is somewhat duplication of RecyclerView getOldPosition() which is 458 * unfortunately cleared after prelayout. 459 */ 460 private int mFocusPositionOffset = 0; 461 462 /** 463 * Extra pixels applied on primary direction. 464 */ 465 private int mPrimaryScrollExtra; 466 467 /** 468 * Force a full layout under certain situations. E.g. Rows change, jump to invisible child. 469 */ 470 private boolean mForceFullLayout; 471 472 /** 473 * True if layout is enabled. 474 */ 475 private boolean mLayoutEnabled = true; 476 477 /** 478 * override child visibility 479 */ 480 private int mChildVisibility = -1; 481 482 /** 483 * The scroll offsets of the viewport relative to the entire view. 484 */ 485 private int mScrollOffsetPrimary; 486 private int mScrollOffsetSecondary; 487 488 /** 489 * User-specified row height/column width. Can be WRAP_CONTENT. 490 */ 491 private int mRowSizeSecondaryRequested; 492 493 /** 494 * The fixed size of each grid item in the secondary direction. This corresponds to 495 * the row height, equal for all rows. Grid items may have variable length 496 * in the primary direction. 497 */ 498 private int mFixedRowSizeSecondary; 499 500 /** 501 * Tracks the secondary size of each row. 502 */ 503 private int[] mRowSizeSecondary; 504 505 /** 506 * Flag controlling whether the current/next layout should 507 * be updating the secondary size of rows. 508 */ 509 private boolean mRowSecondarySizeRefresh; 510 511 /** 512 * The maximum measured size of the view. 513 */ 514 private int mMaxSizeSecondary; 515 516 /** 517 * Margin between items. 518 */ 519 private int mHorizontalSpacing; 520 /** 521 * Margin between items vertically. 522 */ 523 private int mVerticalSpacing; 524 /** 525 * Margin in main direction. 526 */ 527 private int mSpacingPrimary; 528 /** 529 * Margin in second direction. 530 */ 531 private int mSpacingSecondary; 532 /** 533 * How to position child in secondary direction. 534 */ 535 private int mGravity = Gravity.START | Gravity.TOP; 536 /** 537 * The number of rows in the grid. 538 */ 539 private int mNumRows; 540 /** 541 * Number of rows requested, can be 0 to be determined by parent size and 542 * rowHeight. 543 */ 544 private int mNumRowsRequested = 1; 545 546 /** 547 * Saves grid information of each view. 548 */ 549 Grid mGrid; 550 551 /** 552 * Focus Scroll strategy. 553 */ 554 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 555 /** 556 * Defines how item view is aligned in the window. 557 */ 558 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 559 560 /** 561 * Defines how item view is aligned. 562 */ 563 private final ItemAlignment mItemAlignment = new ItemAlignment(); 564 565 /** 566 * Dimensions of the view, width or height depending on orientation. 567 */ 568 private int mSizePrimary; 569 570 /** 571 * Pixels of extra space for layout item (outside the widget) 572 */ 573 private int mExtraLayoutSpace; 574 575 /** 576 * Allow DPAD key to navigate out at the front of the View (where position = 0), 577 * default is false. 578 */ 579 private boolean mFocusOutFront; 580 581 /** 582 * Allow DPAD key to navigate out at the end of the view, default is false. 583 */ 584 private boolean mFocusOutEnd; 585 586 /** 587 * Allow DPAD key to navigate out of second axis. 588 * default is true. 589 */ 590 private boolean mFocusOutSideStart = true; 591 592 /** 593 * Allow DPAD key to navigate out of second axis. 594 */ 595 private boolean mFocusOutSideEnd = true; 596 597 /** 598 * True if focus search is disabled. 599 */ 600 private boolean mFocusSearchDisabled; 601 602 /** 603 * True if prune child, might be disabled during transition. 604 */ 605 private boolean mPruneChild = true; 606 607 /** 608 * True if scroll content, might be disabled during transition. 609 */ 610 private boolean mScrollEnabled = true; 611 612 /** 613 * Temporary variable: an int array of length=2. 614 */ 615 private static int[] sTwoInts = new int[2]; 616 617 /** 618 * Set to true for RTL layout in horizontal orientation 619 */ 620 private boolean mReverseFlowPrimary = false; 621 622 /** 623 * Set to true for RTL layout in vertical orientation 624 */ 625 private boolean mReverseFlowSecondary = false; 626 627 /** 628 * Temporaries used for measuring. 629 */ 630 private int[] mMeasuredDimension = new int[2]; 631 632 final ViewsStateBundle mChildrenStates = new ViewsStateBundle(); 633 634 /** 635 * Optional interface implemented by Adapter. 636 */ 637 private FacetProviderAdapter mFacetProviderAdapter; 638 639 public GridLayoutManager(BaseGridView baseGridView) { 640 mBaseGridView = baseGridView; 641 } 642 643 public void setOrientation(int orientation) { 644 if (orientation != HORIZONTAL && orientation != VERTICAL) { 645 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 646 return; 647 } 648 649 mOrientation = orientation; 650 mOrientationHelper = OrientationHelper.createOrientationHelper(this, mOrientation); 651 mWindowAlignment.setOrientation(orientation); 652 mItemAlignment.setOrientation(orientation); 653 mForceFullLayout = true; 654 } 655 656 public void onRtlPropertiesChanged(int layoutDirection) { 657 if (mOrientation == HORIZONTAL) { 658 mReverseFlowPrimary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 659 mReverseFlowSecondary = false; 660 } else { 661 mReverseFlowSecondary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 662 mReverseFlowPrimary = false; 663 } 664 mWindowAlignment.horizontal.setReversedFlow(layoutDirection == View.LAYOUT_DIRECTION_RTL); 665 } 666 667 public int getFocusScrollStrategy() { 668 return mFocusScrollStrategy; 669 } 670 671 public void setFocusScrollStrategy(int focusScrollStrategy) { 672 mFocusScrollStrategy = focusScrollStrategy; 673 } 674 675 public void setWindowAlignment(int windowAlignment) { 676 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 677 } 678 679 public int getWindowAlignment() { 680 return mWindowAlignment.mainAxis().getWindowAlignment(); 681 } 682 683 public void setWindowAlignmentOffset(int alignmentOffset) { 684 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 685 } 686 687 public int getWindowAlignmentOffset() { 688 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 689 } 690 691 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 692 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 693 } 694 695 public float getWindowAlignmentOffsetPercent() { 696 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 697 } 698 699 public void setItemAlignmentOffset(int alignmentOffset) { 700 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 701 updateChildAlignments(); 702 } 703 704 public int getItemAlignmentOffset() { 705 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 706 } 707 708 public void setItemAlignmentOffsetWithPadding(boolean withPadding) { 709 mItemAlignment.mainAxis().setItemAlignmentOffsetWithPadding(withPadding); 710 updateChildAlignments(); 711 } 712 713 public boolean isItemAlignmentOffsetWithPadding() { 714 return mItemAlignment.mainAxis().isItemAlignmentOffsetWithPadding(); 715 } 716 717 public void setItemAlignmentOffsetPercent(float offsetPercent) { 718 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 719 updateChildAlignments(); 720 } 721 722 public float getItemAlignmentOffsetPercent() { 723 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 724 } 725 726 public void setItemAlignmentViewId(int viewId) { 727 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 728 updateChildAlignments(); 729 } 730 731 public int getItemAlignmentViewId() { 732 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 733 } 734 735 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 736 mFocusOutFront = throughFront; 737 mFocusOutEnd = throughEnd; 738 } 739 740 public void setFocusOutSideAllowed(boolean throughStart, boolean throughEnd) { 741 mFocusOutSideStart = throughStart; 742 mFocusOutSideEnd = throughEnd; 743 } 744 745 public void setNumRows(int numRows) { 746 if (numRows < 0) throw new IllegalArgumentException(); 747 mNumRowsRequested = numRows; 748 } 749 750 /** 751 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 752 */ 753 public void setRowHeight(int height) { 754 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 755 mRowSizeSecondaryRequested = height; 756 } else { 757 throw new IllegalArgumentException("Invalid row height: " + height); 758 } 759 } 760 761 public void setItemSpacing(int space) { 762 mVerticalSpacing = mHorizontalSpacing = space; 763 mSpacingPrimary = mSpacingSecondary = space; 764 } 765 766 public void setVerticalSpacing(int space) { 767 if (mOrientation == VERTICAL) { 768 mSpacingPrimary = mVerticalSpacing = space; 769 } else { 770 mSpacingSecondary = mVerticalSpacing = space; 771 } 772 } 773 774 public void setHorizontalSpacing(int space) { 775 if (mOrientation == HORIZONTAL) { 776 mSpacingPrimary = mHorizontalSpacing = space; 777 } else { 778 mSpacingSecondary = mHorizontalSpacing = space; 779 } 780 } 781 782 public int getVerticalSpacing() { 783 return mVerticalSpacing; 784 } 785 786 public int getHorizontalSpacing() { 787 return mHorizontalSpacing; 788 } 789 790 public void setGravity(int gravity) { 791 mGravity = gravity; 792 } 793 794 protected boolean hasDoneFirstLayout() { 795 return mGrid != null; 796 } 797 798 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 799 mChildSelectedListener = listener; 800 } 801 802 public void setOnChildViewHolderSelectedListener(OnChildViewHolderSelectedListener listener) { 803 if (listener == null) { 804 mChildViewHolderSelectedListeners = null; 805 return; 806 } 807 if (mChildViewHolderSelectedListeners == null) { 808 mChildViewHolderSelectedListeners = new ArrayList<OnChildViewHolderSelectedListener>(); 809 } else { 810 mChildViewHolderSelectedListeners.clear(); 811 } 812 mChildViewHolderSelectedListeners.add(listener); 813 } 814 815 public void addOnChildViewHolderSelectedListener(OnChildViewHolderSelectedListener listener) { 816 if (mChildViewHolderSelectedListeners == null) { 817 mChildViewHolderSelectedListeners = new ArrayList<OnChildViewHolderSelectedListener>(); 818 } 819 mChildViewHolderSelectedListeners.add(listener); 820 } 821 822 public void removeOnChildViewHolderSelectedListener(OnChildViewHolderSelectedListener 823 listener) { 824 if (mChildViewHolderSelectedListeners != null) { 825 mChildViewHolderSelectedListeners.remove(listener); 826 } 827 } 828 829 boolean hasOnChildViewHolderSelectedListener() { 830 return mChildViewHolderSelectedListeners != null && 831 mChildViewHolderSelectedListeners.size() > 0; 832 } 833 834 void fireOnChildViewHolderSelected(RecyclerView parent, RecyclerView.ViewHolder child, 835 int position, int subposition) { 836 if (mChildViewHolderSelectedListeners == null) { 837 return; 838 } 839 for (int i = mChildViewHolderSelectedListeners.size() - 1; i >= 0 ; i--) { 840 mChildViewHolderSelectedListeners.get(i).onChildViewHolderSelected(parent, child, 841 position, subposition); 842 } 843 } 844 845 void setOnChildLaidOutListener(OnChildLaidOutListener listener) { 846 mChildLaidOutListener = listener; 847 } 848 849 private int getPositionByView(View view) { 850 if (view == null) { 851 return NO_POSITION; 852 } 853 LayoutParams params = (LayoutParams) view.getLayoutParams(); 854 if (params == null || params.isItemRemoved()) { 855 // when item is removed, the position value can be any value. 856 return NO_POSITION; 857 } 858 return params.getViewPosition(); 859 } 860 861 private int getSubPositionByView(View view, View childView) { 862 if (view == null || childView == null) { 863 return 0; 864 } 865 final LayoutParams lp = (LayoutParams) view.getLayoutParams(); 866 final ItemAlignmentFacet facet = lp.getItemAlignmentFacet(); 867 if (facet != null) { 868 final ItemAlignmentFacet.ItemAlignmentDef[] defs = facet.getAlignmentDefs(); 869 if (defs.length > 1) { 870 while (childView != view) { 871 int id = childView.getId(); 872 if (id != View.NO_ID) { 873 for (int i = 1; i < defs.length; i++) { 874 if (defs[i].getItemAlignmentFocusViewId() == id) { 875 return i; 876 } 877 } 878 } 879 childView = (View) childView.getParent(); 880 } 881 } 882 } 883 return 0; 884 } 885 886 private int getPositionByIndex(int index) { 887 return getPositionByView(getChildAt(index)); 888 } 889 890 private void dispatchChildSelected() { 891 if (mChildSelectedListener == null && !hasOnChildViewHolderSelectedListener()) { 892 return; 893 } 894 895 if (TRACE) TraceHelper.beginSection("onChildSelected"); 896 View view = mFocusPosition == NO_POSITION ? null : findViewByPosition(mFocusPosition); 897 if (view != null) { 898 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(view); 899 if (mChildSelectedListener != null) { 900 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 901 vh == null? NO_ID: vh.getItemId()); 902 } 903 fireOnChildViewHolderSelected(mBaseGridView, vh, mFocusPosition, mSubFocusPosition); 904 } else { 905 if (mChildSelectedListener != null) { 906 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 907 } 908 fireOnChildViewHolderSelected(mBaseGridView, null, NO_POSITION, 0); 909 } 910 if (TRACE) TraceHelper.endSection(); 911 912 // Children may request layout when a child selection event occurs (such as a change of 913 // padding on the current and previously selected rows). 914 // If in layout, a child requesting layout may have been laid out before the selection 915 // callback. 916 // If it was not, the child will be laid out after the selection callback. 917 // If so, the layout request will be honoured though the view system will emit a double- 918 // layout warning. 919 // If not in layout, we may be scrolling in which case the child layout request will be 920 // eaten by recyclerview. Post a requestLayout. 921 if (!mInLayout && !mBaseGridView.isLayoutRequested()) { 922 int childCount = getChildCount(); 923 for (int i = 0; i < childCount; i++) { 924 if (getChildAt(i).isLayoutRequested()) { 925 forceRequestLayout(); 926 break; 927 } 928 } 929 } 930 } 931 932 @Override 933 public boolean canScrollHorizontally() { 934 // We can scroll horizontally if we have horizontal orientation, or if 935 // we are vertical and have more than one column. 936 return mOrientation == HORIZONTAL || mNumRows > 1; 937 } 938 939 @Override 940 public boolean canScrollVertically() { 941 // We can scroll vertically if we have vertical orientation, or if we 942 // are horizontal and have more than one row. 943 return mOrientation == VERTICAL || mNumRows > 1; 944 } 945 946 @Override 947 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 948 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 949 ViewGroup.LayoutParams.WRAP_CONTENT); 950 } 951 952 @Override 953 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 954 return new LayoutParams(context, attrs); 955 } 956 957 @Override 958 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 959 if (lp instanceof LayoutParams) { 960 return new LayoutParams((LayoutParams) lp); 961 } else if (lp instanceof RecyclerView.LayoutParams) { 962 return new LayoutParams((RecyclerView.LayoutParams) lp); 963 } else if (lp instanceof MarginLayoutParams) { 964 return new LayoutParams((MarginLayoutParams) lp); 965 } else { 966 return new LayoutParams(lp); 967 } 968 } 969 970 protected View getViewForPosition(int position) { 971 return mRecycler.getViewForPosition(position); 972 } 973 974 final int getOpticalLeft(View v) { 975 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 976 } 977 978 final int getOpticalRight(View v) { 979 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 980 } 981 982 final int getOpticalTop(View v) { 983 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 984 } 985 986 final int getOpticalBottom(View v) { 987 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 988 } 989 990 @Override 991 public int getDecoratedLeft(View child) { 992 return super.getDecoratedLeft(child) + ((LayoutParams) child.getLayoutParams()).mLeftInset; 993 } 994 995 @Override 996 public int getDecoratedTop(View child) { 997 return super.getDecoratedTop(child) + ((LayoutParams) child.getLayoutParams()).mTopInset; 998 } 999 1000 @Override 1001 public int getDecoratedRight(View child) { 1002 return super.getDecoratedRight(child) - 1003 ((LayoutParams) child.getLayoutParams()).mRightInset; 1004 } 1005 1006 @Override 1007 public int getDecoratedBottom(View child) { 1008 return super.getDecoratedBottom(child) - 1009 ((LayoutParams) child.getLayoutParams()).mBottomInset; 1010 } 1011 1012 @Override 1013 public void getDecoratedBoundsWithMargins(View view, Rect outBounds) { 1014 super.getDecoratedBoundsWithMargins(view, outBounds); 1015 LayoutParams params = ((LayoutParams) view.getLayoutParams()); 1016 outBounds.left += params.mLeftInset; 1017 outBounds.top += params.mTopInset; 1018 outBounds.right -= params.mRightInset; 1019 outBounds.bottom -= params.mBottomInset; 1020 } 1021 1022 private int getViewMin(View v) { 1023 return mOrientationHelper.getDecoratedStart(v); 1024 } 1025 1026 private int getViewMax(View v) { 1027 return mOrientationHelper.getDecoratedEnd(v); 1028 } 1029 1030 private int getViewPrimarySize(View view) { 1031 getDecoratedBoundsWithMargins(view, sTempRect); 1032 return mOrientation == HORIZONTAL ? sTempRect.width() : sTempRect.height(); 1033 } 1034 1035 private int getViewCenter(View view) { 1036 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 1037 } 1038 1039 private int getViewCenterSecondary(View view) { 1040 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 1041 } 1042 1043 private int getViewCenterX(View v) { 1044 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1045 return p.getOpticalLeft(v) + p.getAlignX(); 1046 } 1047 1048 private int getViewCenterY(View v) { 1049 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1050 return p.getOpticalTop(v) + p.getAlignY(); 1051 } 1052 1053 /** 1054 * Save Recycler and State for convenience. Must be paired with leaveContext(). 1055 */ 1056 private void saveContext(Recycler recycler, State state) { 1057 if (mRecycler != null || mState != null) { 1058 Log.e(TAG, "Recycler information was not released, bug!"); 1059 } 1060 mRecycler = recycler; 1061 mState = state; 1062 } 1063 1064 /** 1065 * Discard saved Recycler and State. 1066 */ 1067 private void leaveContext() { 1068 mRecycler = null; 1069 mState = null; 1070 } 1071 1072 /** 1073 * Re-initialize data structures for a data change or handling invisible 1074 * selection. The method tries its best to preserve position information so 1075 * that staggered grid looks same before and after re-initialize. 1076 * @return true if can fastRelayout() 1077 */ 1078 private boolean layoutInit() { 1079 boolean focusViewWasInTree = mGrid != null && mFocusPosition >= 0 1080 && mFocusPosition >= mGrid.getFirstVisibleIndex() 1081 && mFocusPosition <= mGrid.getLastVisibleIndex(); 1082 final int newItemCount = mState.getItemCount(); 1083 if (newItemCount == 0) { 1084 mFocusPosition = NO_POSITION; 1085 mSubFocusPosition = 0; 1086 } else if (mFocusPosition >= newItemCount) { 1087 mFocusPosition = newItemCount - 1; 1088 mSubFocusPosition = 0; 1089 } else if (mFocusPosition == NO_POSITION && newItemCount > 0) { 1090 // if focus position is never set before, initialize it to 0 1091 mFocusPosition = 0; 1092 mSubFocusPosition = 0; 1093 } 1094 if (!mState.didStructureChange() && mGrid.getFirstVisibleIndex() >= 0 && 1095 !mForceFullLayout && mGrid != null && mGrid.getNumRows() == mNumRows) { 1096 updateScrollController(); 1097 updateScrollSecondAxis(); 1098 mGrid.setSpacing(mSpacingPrimary); 1099 if (!focusViewWasInTree && mFocusPosition != NO_POSITION) { 1100 mGrid.setStart(mFocusPosition); 1101 } 1102 return true; 1103 } else { 1104 mForceFullLayout = false; 1105 int firstVisibleIndex = focusViewWasInTree ? mGrid.getFirstVisibleIndex() : 0; 1106 1107 if (mGrid == null || mNumRows != mGrid.getNumRows() || 1108 mReverseFlowPrimary != mGrid.isReversedFlow()) { 1109 mGrid = Grid.createGrid(mNumRows); 1110 mGrid.setProvider(mGridProvider); 1111 mGrid.setReversedFlow(mReverseFlowPrimary); 1112 } 1113 initScrollController(); 1114 updateScrollSecondAxis(); 1115 mGrid.setSpacing(mSpacingPrimary); 1116 detachAndScrapAttachedViews(mRecycler); 1117 mGrid.resetVisibleIndex(); 1118 if (mFocusPosition == NO_POSITION) { 1119 mBaseGridView.clearFocus(); 1120 } 1121 mWindowAlignment.mainAxis().invalidateScrollMin(); 1122 mWindowAlignment.mainAxis().invalidateScrollMax(); 1123 if (focusViewWasInTree && firstVisibleIndex <= mFocusPosition) { 1124 // if focusView was in tree, we will add item from first visible item 1125 mGrid.setStart(firstVisibleIndex); 1126 } else { 1127 // if focusView was not in tree, it's probably because focus position jumped 1128 // far away from visible range, so use mFocusPosition as start 1129 mGrid.setStart(mFocusPosition); 1130 } 1131 return false; 1132 } 1133 } 1134 1135 private int getRowSizeSecondary(int rowIndex) { 1136 if (mFixedRowSizeSecondary != 0) { 1137 return mFixedRowSizeSecondary; 1138 } 1139 if (mRowSizeSecondary == null) { 1140 return 0; 1141 } 1142 return mRowSizeSecondary[rowIndex]; 1143 } 1144 1145 private int getRowStartSecondary(int rowIndex) { 1146 int start = 0; 1147 // Iterate from left to right, which is a different index traversal 1148 // in RTL flow 1149 if (mReverseFlowSecondary) { 1150 for (int i = mNumRows-1; i > rowIndex; i--) { 1151 start += getRowSizeSecondary(i) + mSpacingSecondary; 1152 } 1153 } else { 1154 for (int i = 0; i < rowIndex; i++) { 1155 start += getRowSizeSecondary(i) + mSpacingSecondary; 1156 } 1157 } 1158 return start; 1159 } 1160 1161 private int getSizeSecondary() { 1162 int rightmostIndex = mReverseFlowSecondary ? 0 : mNumRows - 1; 1163 return getRowStartSecondary(rightmostIndex) + getRowSizeSecondary(rightmostIndex); 1164 } 1165 1166 int getDecoratedMeasuredWidthWithMargin(View v) { 1167 final LayoutParams lp = (LayoutParams) v.getLayoutParams(); 1168 return getDecoratedMeasuredWidth(v) + lp.leftMargin + lp.rightMargin; 1169 } 1170 1171 int getDecoratedMeasuredHeightWithMargin(View v) { 1172 final LayoutParams lp = (LayoutParams) v.getLayoutParams(); 1173 return getDecoratedMeasuredHeight(v) + lp.topMargin + lp.bottomMargin; 1174 } 1175 1176 private void measureScrapChild(int position, int widthSpec, int heightSpec, 1177 int[] measuredDimension) { 1178 View view = mRecycler.getViewForPosition(position); 1179 if (view != null) { 1180 final LayoutParams p = (LayoutParams) view.getLayoutParams(); 1181 calculateItemDecorationsForChild(view, sTempRect); 1182 int widthUsed = p.leftMargin + p.rightMargin + sTempRect.left + sTempRect.right; 1183 int heightUsed = p.topMargin + p.bottomMargin + sTempRect.top + sTempRect.bottom; 1184 1185 int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, 1186 getPaddingLeft() + getPaddingRight() + widthUsed, p.width); 1187 int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, 1188 getPaddingTop() + getPaddingBottom() + heightUsed, p.height); 1189 view.measure(childWidthSpec, childHeightSpec); 1190 1191 measuredDimension[0] = getDecoratedMeasuredWidthWithMargin(view); 1192 measuredDimension[1] = getDecoratedMeasuredHeightWithMargin(view); 1193 mRecycler.recycleView(view); 1194 } 1195 } 1196 1197 private boolean processRowSizeSecondary(boolean measure) { 1198 if (mFixedRowSizeSecondary != 0 || mRowSizeSecondary == null) { 1199 return false; 1200 } 1201 1202 if (TRACE) TraceHelper.beginSection("processRowSizeSecondary"); 1203 CircularIntArray[] rows = mGrid == null ? null : mGrid.getItemPositionsInRows(); 1204 boolean changed = false; 1205 int scrapChildWidth = -1; 1206 int scrapChildHeight = -1; 1207 1208 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 1209 CircularIntArray row = rows == null ? null : rows[rowIndex]; 1210 final int rowItemsPairCount = row == null ? 0 : row.size(); 1211 int rowSize = -1; 1212 for (int rowItemPairIndex = 0; rowItemPairIndex < rowItemsPairCount; 1213 rowItemPairIndex += 2) { 1214 final int rowIndexStart = row.get(rowItemPairIndex); 1215 final int rowIndexEnd = row.get(rowItemPairIndex + 1); 1216 for (int i = rowIndexStart; i <= rowIndexEnd; i++) { 1217 final View view = findViewByPosition(i); 1218 if (view == null) { 1219 continue; 1220 } 1221 if (measure) { 1222 measureChild(view); 1223 } 1224 final int secondarySize = mOrientation == HORIZONTAL ? 1225 getDecoratedMeasuredHeightWithMargin(view) 1226 : getDecoratedMeasuredWidthWithMargin(view); 1227 if (secondarySize > rowSize) { 1228 rowSize = secondarySize; 1229 } 1230 } 1231 } 1232 1233 final int itemCount = mState.getItemCount(); 1234 if (!mBaseGridView.hasFixedSize() && measure && rowSize < 0 && itemCount > 0) { 1235 if (scrapChildWidth < 0 && scrapChildHeight < 0) { 1236 int position; 1237 if (mFocusPosition == NO_POSITION) { 1238 position = 0; 1239 } else if (mFocusPosition >= itemCount) { 1240 position = itemCount - 1; 1241 } else { 1242 position = mFocusPosition; 1243 } 1244 measureScrapChild(position, 1245 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1246 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1247 mMeasuredDimension); 1248 scrapChildWidth = mMeasuredDimension[0]; 1249 scrapChildHeight = mMeasuredDimension[1]; 1250 if (DEBUG) Log.v(TAG, "measured scrap child: " + scrapChildWidth + 1251 " " + scrapChildHeight); 1252 } 1253 rowSize = mOrientation == HORIZONTAL ? scrapChildHeight : scrapChildWidth; 1254 } 1255 if (rowSize < 0) { 1256 rowSize = 0; 1257 } 1258 if (mRowSizeSecondary[rowIndex] != rowSize) { 1259 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 1260 ", " + rowSize); 1261 mRowSizeSecondary[rowIndex] = rowSize; 1262 changed = true; 1263 } 1264 } 1265 1266 if (TRACE) TraceHelper.endSection(); 1267 return changed; 1268 } 1269 1270 /** 1271 * Checks if we need to update row secondary sizes. 1272 */ 1273 private void updateRowSecondarySizeRefresh() { 1274 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 1275 if (mRowSecondarySizeRefresh) { 1276 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 1277 forceRequestLayout(); 1278 } 1279 } 1280 1281 private void forceRequestLayout() { 1282 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 1283 // RecyclerView prevents us from requesting layout in many cases 1284 // (during layout, during scroll, etc.) 1285 // For secondary row size wrap_content support we currently need a 1286 // second layout pass to update the measured size after having measured 1287 // and added child views in layoutChildren. 1288 // Force the second layout by posting a delayed runnable. 1289 // TODO: investigate allowing a second layout pass, 1290 // or move child add/measure logic to the measure phase. 1291 ViewCompat.postOnAnimation(mBaseGridView, mRequestLayoutRunnable); 1292 } 1293 1294 private final Runnable mRequestLayoutRunnable = new Runnable() { 1295 @Override 1296 public void run() { 1297 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 1298 requestLayout(); 1299 } 1300 }; 1301 1302 @Override 1303 public void onMeasure(Recycler recycler, State state, int widthSpec, int heightSpec) { 1304 saveContext(recycler, state); 1305 1306 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 1307 int measuredSizeSecondary; 1308 if (mOrientation == HORIZONTAL) { 1309 sizePrimary = MeasureSpec.getSize(widthSpec); 1310 sizeSecondary = MeasureSpec.getSize(heightSpec); 1311 modeSecondary = MeasureSpec.getMode(heightSpec); 1312 paddingSecondary = getPaddingTop() + getPaddingBottom(); 1313 } else { 1314 sizeSecondary = MeasureSpec.getSize(widthSpec); 1315 sizePrimary = MeasureSpec.getSize(heightSpec); 1316 modeSecondary = MeasureSpec.getMode(widthSpec); 1317 paddingSecondary = getPaddingLeft() + getPaddingRight(); 1318 } 1319 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 1320 " heightSpec " + Integer.toHexString(heightSpec) + 1321 " modeSecondary " + Integer.toHexString(modeSecondary) + 1322 " sizeSecondary " + sizeSecondary + " " + this); 1323 1324 mMaxSizeSecondary = sizeSecondary; 1325 1326 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 1327 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1328 mFixedRowSizeSecondary = 0; 1329 1330 if (mRowSizeSecondary == null || mRowSizeSecondary.length != mNumRows) { 1331 mRowSizeSecondary = new int[mNumRows]; 1332 } 1333 1334 // Measure all current children and update cached row heights 1335 processRowSizeSecondary(true); 1336 1337 switch (modeSecondary) { 1338 case MeasureSpec.UNSPECIFIED: 1339 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 1340 break; 1341 case MeasureSpec.AT_MOST: 1342 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 1343 mMaxSizeSecondary); 1344 break; 1345 case MeasureSpec.EXACTLY: 1346 measuredSizeSecondary = mMaxSizeSecondary; 1347 break; 1348 default: 1349 throw new IllegalStateException("wrong spec"); 1350 } 1351 1352 } else { 1353 switch (modeSecondary) { 1354 case MeasureSpec.UNSPECIFIED: 1355 mFixedRowSizeSecondary = mRowSizeSecondaryRequested == 0 ? 1356 sizeSecondary - paddingSecondary: mRowSizeSecondaryRequested; 1357 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1358 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mSpacingSecondary 1359 * (mNumRows - 1) + paddingSecondary; 1360 break; 1361 case MeasureSpec.AT_MOST: 1362 case MeasureSpec.EXACTLY: 1363 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 1364 mNumRows = 1; 1365 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 1366 } else if (mNumRowsRequested == 0) { 1367 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1368 mNumRows = (sizeSecondary + mSpacingSecondary) 1369 / (mRowSizeSecondaryRequested + mSpacingSecondary); 1370 } else if (mRowSizeSecondaryRequested == 0) { 1371 mNumRows = mNumRowsRequested; 1372 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mSpacingSecondary 1373 * (mNumRows - 1)) / mNumRows; 1374 } else { 1375 mNumRows = mNumRowsRequested; 1376 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1377 } 1378 measuredSizeSecondary = sizeSecondary; 1379 if (modeSecondary == MeasureSpec.AT_MOST) { 1380 int childrenSize = mFixedRowSizeSecondary * mNumRows + mSpacingSecondary 1381 * (mNumRows - 1) + paddingSecondary; 1382 if (childrenSize < measuredSizeSecondary) { 1383 measuredSizeSecondary = childrenSize; 1384 } 1385 } 1386 break; 1387 default: 1388 throw new IllegalStateException("wrong spec"); 1389 } 1390 } 1391 if (mOrientation == HORIZONTAL) { 1392 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1393 } else { 1394 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1395 } 1396 if (DEBUG) { 1397 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1398 " measuredSizeSecondary " + measuredSizeSecondary + 1399 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1400 " mNumRows " + mNumRows); 1401 } 1402 leaveContext(); 1403 } 1404 1405 private void measureChild(View child) { 1406 if (TRACE) TraceHelper.beginSection("measureChild"); 1407 final LayoutParams lp = (LayoutParams) child.getLayoutParams(); 1408 calculateItemDecorationsForChild(child, sTempRect); 1409 int widthUsed = lp.leftMargin + lp.rightMargin + sTempRect.left + sTempRect.right; 1410 int heightUsed = lp.topMargin + lp.bottomMargin + sTempRect.top + sTempRect.bottom; 1411 1412 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1413 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1414 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1415 int widthSpec, heightSpec; 1416 1417 if (mOrientation == HORIZONTAL) { 1418 widthSpec = ViewGroup.getChildMeasureSpec( 1419 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), widthUsed, lp.width); 1420 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, heightUsed, lp.height); 1421 } else { 1422 heightSpec = ViewGroup.getChildMeasureSpec( 1423 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), heightUsed, lp.height); 1424 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, widthUsed, lp.width); 1425 } 1426 child.measure(widthSpec, heightSpec); 1427 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1428 " widthSpec " + Integer.toHexString(widthSpec) + 1429 " heightSpec " + Integer.toHexString(heightSpec) + 1430 " measuredWidth " + child.getMeasuredWidth() + 1431 " measuredHeight " + child.getMeasuredHeight()); 1432 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1433 if (TRACE) TraceHelper.endSection(); 1434 } 1435 1436 /** 1437 * Get facet from the ViewHolder or the viewType. 1438 */ 1439 private <E> E getFacet(RecyclerView.ViewHolder vh, Class<? extends E> facetClass) { 1440 E facet = null; 1441 if (vh instanceof FacetProvider) { 1442 facet = (E) ((FacetProvider) vh).getFacet(facetClass); 1443 } 1444 if (facet == null && mFacetProviderAdapter != null) { 1445 FacetProvider p = mFacetProviderAdapter.getFacetProvider(vh.getItemViewType()); 1446 if (p != null) { 1447 facet = (E) p.getFacet(facetClass); 1448 } 1449 } 1450 return facet; 1451 } 1452 1453 private Grid.Provider mGridProvider = new Grid.Provider() { 1454 1455 @Override 1456 public int getCount() { 1457 return mState.getItemCount(); 1458 } 1459 1460 @Override 1461 public int createItem(int index, boolean append, Object[] item) { 1462 if (TRACE) TraceHelper.beginSection("createItem"); 1463 if (TRACE) TraceHelper.beginSection("getview"); 1464 View v = getViewForPosition(index); 1465 if (TRACE) TraceHelper.endSection(); 1466 LayoutParams lp = (LayoutParams) v.getLayoutParams(); 1467 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(v); 1468 lp.setItemAlignmentFacet((ItemAlignmentFacet)getFacet(vh, ItemAlignmentFacet.class)); 1469 // See recyclerView docs: we don't need re-add scraped view if it was removed. 1470 if (!lp.isItemRemoved()) { 1471 if (TRACE) TraceHelper.beginSection("addView"); 1472 if (append) { 1473 addView(v); 1474 } else { 1475 addView(v, 0); 1476 } 1477 if (TRACE) TraceHelper.endSection(); 1478 if (mChildVisibility != -1) { 1479 v.setVisibility(mChildVisibility); 1480 } 1481 1482 if (mPendingMoveSmoothScroller != null) { 1483 mPendingMoveSmoothScroller.consumePendingMovesBeforeLayout(); 1484 } 1485 int subindex = getSubPositionByView(v, v.findFocus()); 1486 if (!mInLayout) { 1487 // when we are appending item during scroll pass and the item's position 1488 // matches the mFocusPosition, we should signal a childSelected event. 1489 // However if we are still running PendingMoveSmoothScroller, we defer and 1490 // signal the event in PendingMoveSmoothScroller.onStop(). This can 1491 // avoid lots of childSelected events during a long smooth scrolling and 1492 // increase performance. 1493 if (index == mFocusPosition && subindex == mSubFocusPosition 1494 && mPendingMoveSmoothScroller == null) { 1495 dispatchChildSelected(); 1496 } 1497 } else if (!mInFastRelayout) { 1498 // fastRelayout will dispatch event at end of onLayoutChildren(). 1499 // For full layout, two situations here: 1500 // 1. mInLayoutSearchFocus is false, dispatchChildSelected() at mFocusPosition. 1501 // 2. mInLayoutSearchFocus is true: dispatchChildSelected() on first child 1502 // equal to or after mFocusPosition that can take focus. 1503 if (!mInLayoutSearchFocus && index == mFocusPosition 1504 && subindex == mSubFocusPosition) { 1505 dispatchChildSelected(); 1506 } else if (mInLayoutSearchFocus && index >= mFocusPosition 1507 && v.hasFocusable()) { 1508 mFocusPosition = index; 1509 mSubFocusPosition = subindex; 1510 mInLayoutSearchFocus = false; 1511 dispatchChildSelected(); 1512 } 1513 } 1514 measureChild(v); 1515 } 1516 item[0] = v; 1517 return mOrientation == HORIZONTAL ? getDecoratedMeasuredWidthWithMargin(v) 1518 : getDecoratedMeasuredHeightWithMargin(v); 1519 } 1520 1521 @Override 1522 public void addItem(Object item, int index, int length, int rowIndex, int edge) { 1523 View v = (View) item; 1524 int start, end; 1525 if (edge == Integer.MIN_VALUE || edge == Integer.MAX_VALUE) { 1526 edge = !mGrid.isReversedFlow() ? mWindowAlignment.mainAxis().getPaddingLow() 1527 : mWindowAlignment.mainAxis().getSize() 1528 - mWindowAlignment.mainAxis().getPaddingHigh(); 1529 } 1530 boolean edgeIsMin = !mGrid.isReversedFlow(); 1531 if (edgeIsMin) { 1532 start = edge; 1533 end = edge + length; 1534 } else { 1535 start = edge - length; 1536 end = edge; 1537 } 1538 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1539 mChildrenStates.loadView(v, index); 1540 layoutChild(rowIndex, v, start, end, startSecondary); 1541 if (DEBUG) { 1542 Log.d(getTag(), "addView " + index + " " + v); 1543 } 1544 if (TRACE) TraceHelper.endSection(); 1545 1546 if (index == mGrid.getFirstVisibleIndex()) { 1547 if (!mGrid.isReversedFlow()) { 1548 updateScrollMin(); 1549 } else { 1550 updateScrollMax(); 1551 } 1552 } 1553 if (index == mGrid.getLastVisibleIndex()) { 1554 if (!mGrid.isReversedFlow()) { 1555 updateScrollMax(); 1556 } else { 1557 updateScrollMin(); 1558 } 1559 } 1560 if (!mInLayout && mPendingMoveSmoothScroller != null) { 1561 mPendingMoveSmoothScroller.consumePendingMovesAfterLayout(); 1562 } 1563 if (mChildLaidOutListener != null) { 1564 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(v); 1565 mChildLaidOutListener.onChildLaidOut(mBaseGridView, v, index, 1566 vh == null ? NO_ID : vh.getItemId()); 1567 } 1568 } 1569 1570 @Override 1571 public void removeItem(int index) { 1572 if (TRACE) TraceHelper.beginSection("removeItem"); 1573 View v = findViewByPosition(index); 1574 if (mInLayout) { 1575 detachAndScrapView(v, mRecycler); 1576 } else { 1577 removeAndRecycleView(v, mRecycler); 1578 } 1579 if (TRACE) TraceHelper.endSection(); 1580 } 1581 1582 @Override 1583 public int getEdge(int index) { 1584 if (mReverseFlowPrimary) { 1585 return getViewMax(findViewByPosition(index)); 1586 } else { 1587 return getViewMin(findViewByPosition(index)); 1588 } 1589 } 1590 1591 @Override 1592 public int getSize(int index) { 1593 return getViewPrimarySize(findViewByPosition(index)); 1594 } 1595 }; 1596 1597 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1598 if (TRACE) TraceHelper.beginSection("layoutChild"); 1599 int sizeSecondary = mOrientation == HORIZONTAL ? getDecoratedMeasuredHeightWithMargin(v) 1600 : getDecoratedMeasuredWidthWithMargin(v); 1601 if (mFixedRowSizeSecondary > 0) { 1602 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1603 } 1604 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1605 final int horizontalGravity = (mReverseFlowPrimary || mReverseFlowSecondary) ? 1606 Gravity.getAbsoluteGravity(mGravity & Gravity.RELATIVE_HORIZONTAL_GRAVITY_MASK, View.LAYOUT_DIRECTION_RTL) : 1607 mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1608 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1609 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1610 // do nothing 1611 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1612 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1613 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1614 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1615 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1616 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1617 } 1618 int left, top, right, bottom; 1619 if (mOrientation == HORIZONTAL) { 1620 left = start; 1621 top = startSecondary; 1622 right = end; 1623 bottom = startSecondary + sizeSecondary; 1624 } else { 1625 top = start; 1626 left = startSecondary; 1627 bottom = end; 1628 right = startSecondary + sizeSecondary; 1629 } 1630 LayoutParams params = (LayoutParams) v.getLayoutParams(); 1631 layoutDecoratedWithMargins(v, left, top, right, bottom); 1632 // Now super.getDecoratedBoundsWithMargins() includes the extra space for optical bounds, 1633 // subtracting it from value passed in layoutDecoratedWithMargins(), we can get the optical 1634 // bounds insets. 1635 super.getDecoratedBoundsWithMargins(v, sTempRect); 1636 params.setOpticalInsets(left - sTempRect.left, top - sTempRect.top, 1637 sTempRect.right - right, sTempRect.bottom - bottom); 1638 updateChildAlignments(v); 1639 if (TRACE) TraceHelper.endSection(); 1640 } 1641 1642 private void updateChildAlignments(View v) { 1643 final LayoutParams p = (LayoutParams) v.getLayoutParams(); 1644 if (p.getItemAlignmentFacet() == null) { 1645 // Fallback to global settings on grid view 1646 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1647 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1648 } else { 1649 // Use ItemAlignmentFacet defined on specific ViewHolder 1650 p.calculateItemAlignments(mOrientation, v); 1651 if (mOrientation == HORIZONTAL) { 1652 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1653 } else { 1654 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1655 } 1656 } 1657 } 1658 1659 private void updateChildAlignments() { 1660 for (int i = 0, c = getChildCount(); i < c; i++) { 1661 updateChildAlignments(getChildAt(i)); 1662 } 1663 } 1664 1665 void setExtraLayoutSpace(int extraLayoutSpace) { 1666 if (mExtraLayoutSpace == extraLayoutSpace) { 1667 return; 1668 } else if (mExtraLayoutSpace < 0) { 1669 throw new IllegalArgumentException("ExtraLayoutSpace must >= 0"); 1670 } 1671 mExtraLayoutSpace = extraLayoutSpace; 1672 requestLayout(); 1673 } 1674 1675 int getExtraLayoutSpace() { 1676 return mExtraLayoutSpace; 1677 } 1678 1679 private void removeInvisibleViewsAtEnd() { 1680 if (mPruneChild) { 1681 mGrid.removeInvisibleItemsAtEnd(mFocusPosition, 1682 mReverseFlowPrimary ? -mExtraLayoutSpace : mSizePrimary + mExtraLayoutSpace); 1683 } 1684 } 1685 1686 private void removeInvisibleViewsAtFront() { 1687 if (mPruneChild) { 1688 mGrid.removeInvisibleItemsAtFront(mFocusPosition, 1689 mReverseFlowPrimary ? mSizePrimary + mExtraLayoutSpace: -mExtraLayoutSpace); 1690 } 1691 } 1692 1693 private boolean appendOneColumnVisibleItems() { 1694 return mGrid.appendOneColumnVisibleItems(); 1695 } 1696 1697 private boolean prependOneColumnVisibleItems() { 1698 return mGrid.prependOneColumnVisibleItems(); 1699 } 1700 1701 private void appendVisibleItems() { 1702 mGrid.appendVisibleItems(mReverseFlowPrimary ? -mExtraLayoutSpace 1703 : mSizePrimary + mExtraLayoutSpace); 1704 } 1705 1706 private void prependVisibleItems() { 1707 mGrid.prependVisibleItems(mReverseFlowPrimary ? mSizePrimary + mExtraLayoutSpace 1708 : -mExtraLayoutSpace); 1709 } 1710 1711 /** 1712 * Fast layout when there is no structure change, adapter change, etc. 1713 * It will layout all views was layout requested or updated, until hit a view 1714 * with different size, then it break and detachAndScrap all views after that. 1715 */ 1716 private void fastRelayout() { 1717 boolean invalidateAfter = false; 1718 final int childCount = getChildCount(); 1719 int position = -1; 1720 for (int index = 0; index < childCount; index++) { 1721 View view = getChildAt(index); 1722 position = getPositionByIndex(index); 1723 Grid.Location location = mGrid.getLocation(position); 1724 if (location == null) { 1725 if (DEBUG) Log.w(getTag(), "fastRelayout(): no Location at " + position); 1726 invalidateAfter = true; 1727 break; 1728 } 1729 1730 int startSecondary = getRowStartSecondary(location.row) - mScrollOffsetSecondary; 1731 int primarySize, end; 1732 int start = getViewMin(view); 1733 int oldPrimarySize = getViewPrimarySize(view); 1734 1735 LayoutParams lp = (LayoutParams) view.getLayoutParams(); 1736 if (lp.viewNeedsUpdate()) { 1737 int viewIndex = mBaseGridView.indexOfChild(view); 1738 detachAndScrapView(view, mRecycler); 1739 view = getViewForPosition(position); 1740 addView(view, viewIndex); 1741 } 1742 1743 measureChild(view); 1744 if (mOrientation == HORIZONTAL) { 1745 primarySize = getDecoratedMeasuredWidthWithMargin(view); 1746 end = start + primarySize; 1747 } else { 1748 primarySize = getDecoratedMeasuredHeightWithMargin(view); 1749 end = start + primarySize; 1750 } 1751 layoutChild(location.row, view, start, end, startSecondary); 1752 if (oldPrimarySize != primarySize) { 1753 // size changed invalidate remaining Locations 1754 if (DEBUG) Log.d(getTag(), "fastRelayout: view size changed at " + position); 1755 invalidateAfter = true; 1756 break; 1757 } 1758 } 1759 if (invalidateAfter) { 1760 final int savedLastPos = mGrid.getLastVisibleIndex(); 1761 mGrid.invalidateItemsAfter(position); 1762 if (mPruneChild) { 1763 // in regular prune child mode, we just append items up to edge limit 1764 appendVisibleItems(); 1765 if (mFocusPosition >= 0 && mFocusPosition <= savedLastPos) { 1766 // make sure add focus view back: the view might be outside edge limit 1767 // when there is delta in onLayoutChildren(). 1768 while (mGrid.getLastVisibleIndex() < mFocusPosition) { 1769 mGrid.appendOneColumnVisibleItems(); 1770 } 1771 } 1772 } else { 1773 // prune disabled(e.g. in RowsFragment transition): append all removed items 1774 while (mGrid.appendOneColumnVisibleItems() 1775 && mGrid.getLastVisibleIndex() < savedLastPos); 1776 } 1777 } 1778 updateScrollMin(); 1779 updateScrollMax(); 1780 updateScrollSecondAxis(); 1781 } 1782 1783 @Override 1784 public void removeAndRecycleAllViews(RecyclerView.Recycler recycler) { 1785 if (TRACE) TraceHelper.beginSection("removeAndRecycleAllViews"); 1786 if (DEBUG) Log.v(TAG, "removeAndRecycleAllViews " + getChildCount()); 1787 for (int i = getChildCount() - 1; i >= 0; i--) { 1788 removeAndRecycleViewAt(i, recycler); 1789 } 1790 if (TRACE) TraceHelper.endSection(); 1791 } 1792 1793 // called by onLayoutChildren, either focus to FocusPosition or declare focusViewAvailable 1794 // and scroll to the view if framework focus on it. 1795 private void scrollToFocusViewInLayout(boolean hadFocus, boolean alignToView) { 1796 View focusView = findViewByPosition(mFocusPosition); 1797 if (focusView != null && alignToView) { 1798 scrollToView(focusView, false); 1799 } 1800 if (focusView != null && hadFocus && !focusView.hasFocus()) { 1801 focusView.requestFocus(); 1802 } else if (!hadFocus && !mBaseGridView.hasFocus()) { 1803 if (focusView != null && focusView.hasFocusable()) { 1804 mBaseGridView.focusableViewAvailable(focusView); 1805 } else { 1806 for (int i = 0, count = getChildCount(); i < count; i++) { 1807 focusView = getChildAt(i); 1808 if (focusView != null && focusView.hasFocusable()) { 1809 mBaseGridView.focusableViewAvailable(focusView); 1810 break; 1811 } 1812 } 1813 // focusViewAvailable() might focus to the view, scroll to it if that is the case. 1814 if (alignToView && focusView != null && focusView.hasFocus()) { 1815 scrollToView(focusView, false); 1816 } 1817 } 1818 } 1819 } 1820 1821 // Lays out items based on the current scroll position 1822 @Override 1823 public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) { 1824 if (DEBUG) { 1825 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1826 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1827 + " inPreLayout " + state.isPreLayout() 1828 + " didStructureChange " + state.didStructureChange() 1829 + " mForceFullLayout " + mForceFullLayout); 1830 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1831 } 1832 1833 if (mNumRows == 0) { 1834 // haven't done measure yet 1835 return; 1836 } 1837 final int itemCount = state.getItemCount(); 1838 if (itemCount < 0) { 1839 return; 1840 } 1841 1842 if (!mLayoutEnabled) { 1843 discardLayoutInfo(); 1844 removeAndRecycleAllViews(recycler); 1845 return; 1846 } 1847 mInLayout = true; 1848 1849 if (state.didStructureChange()) { 1850 // didStructureChange() == true means attached item has been removed/added. 1851 // scroll animation: we are unable to continue a scroll animation, 1852 // kill the scroll animation, and let ItemAnimation move the item to new position. 1853 // position smooth scroller: kill the animation and stop at final position. 1854 // pending smooth scroller: stop and scroll to current focus position. 1855 mBaseGridView.stopScroll(); 1856 } 1857 final boolean scrollToFocus = !isSmoothScrolling() 1858 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED; 1859 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1860 mFocusPosition = mFocusPosition + mFocusPositionOffset; 1861 mSubFocusPosition = 0; 1862 } 1863 mFocusPositionOffset = 0; 1864 saveContext(recycler, state); 1865 1866 View savedFocusView = findViewByPosition(mFocusPosition); 1867 int savedFocusPos = mFocusPosition; 1868 int savedSubFocusPos = mSubFocusPosition; 1869 boolean hadFocus = mBaseGridView.hasFocus(); 1870 1871 // Track the old focus view so we can adjust our system scroll position 1872 // so that any scroll animations happening now will remain valid. 1873 // We must use same delta in Pre Layout (if prelayout exists) and second layout. 1874 // So we cache the deltas in PreLayout and use it in second layout. 1875 int delta = 0, deltaSecondary = 0; 1876 if (mFocusPosition != NO_POSITION && scrollToFocus 1877 && mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE) { 1878 // FIXME: we should get the remaining scroll animation offset from RecyclerView 1879 if (savedFocusView != null) { 1880 if (getScrollPosition(savedFocusView, savedFocusView.findFocus(), sTwoInts)) { 1881 delta = sTwoInts[0]; 1882 deltaSecondary = sTwoInts[1]; 1883 } 1884 } 1885 } 1886 1887 if (mInFastRelayout = layoutInit()) { 1888 fastRelayout(); 1889 // appends items till focus position. 1890 if (mFocusPosition != NO_POSITION) { 1891 scrollToFocusViewInLayout(hadFocus, scrollToFocus); 1892 } 1893 } else { 1894 mInLayoutSearchFocus = hadFocus; 1895 if (mFocusPosition != NO_POSITION) { 1896 // appends items till focus position. 1897 while (appendOneColumnVisibleItems() 1898 && findViewByPosition(mFocusPosition) == null) ; 1899 } 1900 // multiple rounds: scrollToView of first round may drag first/last child into 1901 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1902 int oldFirstVisible; 1903 int oldLastVisible; 1904 do { 1905 updateScrollMin(); 1906 updateScrollMax(); 1907 oldFirstVisible = mGrid.getFirstVisibleIndex(); 1908 oldLastVisible = mGrid.getLastVisibleIndex(); 1909 scrollToFocusViewInLayout(hadFocus, true); 1910 appendVisibleItems(); 1911 prependVisibleItems(); 1912 removeInvisibleViewsAtFront(); 1913 removeInvisibleViewsAtEnd(); 1914 } while (mGrid.getFirstVisibleIndex() != oldFirstVisible || 1915 mGrid.getLastVisibleIndex() != oldLastVisible); 1916 } 1917 1918 if (scrollToFocus) { 1919 scrollDirectionPrimary(-delta); 1920 scrollDirectionSecondary(-deltaSecondary); 1921 } 1922 appendVisibleItems(); 1923 prependVisibleItems(); 1924 removeInvisibleViewsAtFront(); 1925 removeInvisibleViewsAtEnd(); 1926 1927 if (DEBUG) { 1928 StringWriter sw = new StringWriter(); 1929 PrintWriter pw = new PrintWriter(sw); 1930 mGrid.debugPrint(pw); 1931 Log.d(getTag(), sw.toString()); 1932 } 1933 1934 if (mRowSecondarySizeRefresh) { 1935 mRowSecondarySizeRefresh = false; 1936 } else { 1937 updateRowSecondarySizeRefresh(); 1938 } 1939 1940 // For fastRelayout, only dispatch event when focus position changes. 1941 if (mInFastRelayout && (mFocusPosition != savedFocusPos || mSubFocusPosition != 1942 savedSubFocusPos || findViewByPosition(mFocusPosition) != savedFocusView)) { 1943 dispatchChildSelected(); 1944 } else if (!mInFastRelayout && mInLayoutSearchFocus) { 1945 // For full layout we dispatchChildSelected() in createItem() unless searched all 1946 // children and found none is focusable then dispatchChildSelected() here. 1947 dispatchChildSelected(); 1948 } 1949 1950 mInLayout = false; 1951 leaveContext(); 1952 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1953 } 1954 1955 private void offsetChildrenSecondary(int increment) { 1956 final int childCount = getChildCount(); 1957 if (mOrientation == HORIZONTAL) { 1958 for (int i = 0; i < childCount; i++) { 1959 getChildAt(i).offsetTopAndBottom(increment); 1960 } 1961 } else { 1962 for (int i = 0; i < childCount; i++) { 1963 getChildAt(i).offsetLeftAndRight(increment); 1964 } 1965 } 1966 } 1967 1968 private void offsetChildrenPrimary(int increment) { 1969 final int childCount = getChildCount(); 1970 if (mOrientation == VERTICAL) { 1971 for (int i = 0; i < childCount; i++) { 1972 getChildAt(i).offsetTopAndBottom(increment); 1973 } 1974 } else { 1975 for (int i = 0; i < childCount; i++) { 1976 getChildAt(i).offsetLeftAndRight(increment); 1977 } 1978 } 1979 } 1980 1981 @Override 1982 public int scrollHorizontallyBy(int dx, Recycler recycler, RecyclerView.State state) { 1983 if (DEBUG) Log.v(getTag(), "scrollHorizontallyBy " + dx); 1984 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1985 return 0; 1986 } 1987 saveContext(recycler, state); 1988 mInScroll = true; 1989 int result; 1990 if (mOrientation == HORIZONTAL) { 1991 result = scrollDirectionPrimary(dx); 1992 } else { 1993 result = scrollDirectionSecondary(dx); 1994 } 1995 leaveContext(); 1996 mInScroll = false; 1997 return result; 1998 } 1999 2000 @Override 2001 public int scrollVerticallyBy(int dy, Recycler recycler, RecyclerView.State state) { 2002 if (DEBUG) Log.v(getTag(), "scrollVerticallyBy " + dy); 2003 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 2004 return 0; 2005 } 2006 mInScroll = true; 2007 saveContext(recycler, state); 2008 int result; 2009 if (mOrientation == VERTICAL) { 2010 result = scrollDirectionPrimary(dy); 2011 } else { 2012 result = scrollDirectionSecondary(dy); 2013 } 2014 leaveContext(); 2015 mInScroll = false; 2016 return result; 2017 } 2018 2019 // scroll in main direction may add/prune views 2020 private int scrollDirectionPrimary(int da) { 2021 if (TRACE) TraceHelper.beginSection("scrollPrimary"); 2022 boolean isMaxUnknown = false, isMinUnknown = false; 2023 int minScroll = 0, maxScroll = 0; 2024 if (da > 0) { 2025 isMaxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 2026 if (!isMaxUnknown) { 2027 maxScroll = mWindowAlignment.mainAxis().getMaxScroll(); 2028 if (mScrollOffsetPrimary + da > maxScroll) { 2029 da = maxScroll - mScrollOffsetPrimary; 2030 } 2031 } 2032 } else if (da < 0) { 2033 isMinUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 2034 if (!isMinUnknown) { 2035 minScroll = mWindowAlignment.mainAxis().getMinScroll(); 2036 if (mScrollOffsetPrimary + da < minScroll) { 2037 da = minScroll - mScrollOffsetPrimary; 2038 } 2039 } 2040 } 2041 if (da == 0) { 2042 if (TRACE) TraceHelper.endSection(); 2043 return 0; 2044 } 2045 offsetChildrenPrimary(-da); 2046 mScrollOffsetPrimary += da; 2047 if (mInLayout) { 2048 if (TRACE) TraceHelper.endSection(); 2049 return da; 2050 } 2051 2052 int childCount = getChildCount(); 2053 boolean updated; 2054 2055 if (mReverseFlowPrimary ? da > 0 : da < 0) { 2056 prependVisibleItems(); 2057 } else { 2058 appendVisibleItems(); 2059 } 2060 updated = getChildCount() > childCount; 2061 childCount = getChildCount(); 2062 2063 if (TRACE) TraceHelper.beginSection("remove"); 2064 if (mReverseFlowPrimary ? da > 0 : da < 0) { 2065 removeInvisibleViewsAtEnd(); 2066 } else { 2067 removeInvisibleViewsAtFront(); 2068 } 2069 if (TRACE) TraceHelper.endSection(); 2070 updated |= getChildCount() < childCount; 2071 if (updated) { 2072 updateRowSecondarySizeRefresh(); 2073 } 2074 2075 mBaseGridView.invalidate(); 2076 if (TRACE) TraceHelper.endSection(); 2077 return da; 2078 } 2079 2080 // scroll in second direction will not add/prune views 2081 private int scrollDirectionSecondary(int dy) { 2082 if (dy == 0) { 2083 return 0; 2084 } 2085 offsetChildrenSecondary(-dy); 2086 mScrollOffsetSecondary += dy; 2087 mBaseGridView.invalidate(); 2088 return dy; 2089 } 2090 2091 private void updateScrollMax() { 2092 int highVisiblePos = (!mReverseFlowPrimary) ? mGrid.getLastVisibleIndex() 2093 : mGrid.getFirstVisibleIndex(); 2094 int highMaxPos = (!mReverseFlowPrimary) ? mState.getItemCount() - 1 : 0; 2095 if (highVisiblePos < 0) { 2096 return; 2097 } 2098 final boolean highAvailable = highVisiblePos == highMaxPos; 2099 final boolean maxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 2100 if (!highAvailable && maxUnknown) { 2101 return; 2102 } 2103 int maxEdge = mGrid.findRowMax(true, sTwoInts) + mScrollOffsetPrimary; 2104 int rowIndex = sTwoInts[0]; 2105 int pos = sTwoInts[1]; 2106 int savedMaxEdge = mWindowAlignment.mainAxis().getMaxEdge(); 2107 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 2108 int maxScroll = getPrimarySystemScrollPositionOfChildMax(findViewByPosition(pos)); 2109 mWindowAlignment.mainAxis().setMaxEdge(savedMaxEdge); 2110 2111 if (highAvailable) { 2112 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 2113 mWindowAlignment.mainAxis().setMaxScroll(maxScroll); 2114 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge + 2115 " scrollMax to " + maxScroll); 2116 } else { 2117 mWindowAlignment.mainAxis().invalidateScrollMax(); 2118 if (DEBUG) Log.v(getTag(), "Invalidate scrollMax since it should be " 2119 + "greater than " + maxScroll); 2120 } 2121 } 2122 2123 private void updateScrollMin() { 2124 int lowVisiblePos = (!mReverseFlowPrimary) ? mGrid.getFirstVisibleIndex() 2125 : mGrid.getLastVisibleIndex(); 2126 int lowMinPos = (!mReverseFlowPrimary) ? 0 : mState.getItemCount() - 1; 2127 if (lowVisiblePos < 0) { 2128 return; 2129 } 2130 final boolean lowAvailable = lowVisiblePos == lowMinPos; 2131 final boolean minUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 2132 if (!lowAvailable && minUnknown) { 2133 return; 2134 } 2135 int minEdge = mGrid.findRowMin(false, sTwoInts) + mScrollOffsetPrimary; 2136 int rowIndex = sTwoInts[0]; 2137 int pos = sTwoInts[1]; 2138 int savedMinEdge = mWindowAlignment.mainAxis().getMinEdge(); 2139 mWindowAlignment.mainAxis().setMinEdge(minEdge); 2140 int minScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 2141 mWindowAlignment.mainAxis().setMinEdge(savedMinEdge); 2142 2143 if (lowAvailable) { 2144 mWindowAlignment.mainAxis().setMinEdge(minEdge); 2145 mWindowAlignment.mainAxis().setMinScroll(minScroll); 2146 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge + 2147 " scrollMin to " + minScroll); 2148 } else { 2149 mWindowAlignment.mainAxis().invalidateScrollMin(); 2150 if (DEBUG) Log.v(getTag(), "Invalidate scrollMin, since it should be " 2151 + "less than " + minScroll); 2152 } 2153 } 2154 2155 private void updateScrollSecondAxis() { 2156 mWindowAlignment.secondAxis().setMinEdge(0); 2157 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 2158 } 2159 2160 private void initScrollController() { 2161 mWindowAlignment.reset(); 2162 mWindowAlignment.horizontal.setSize(getWidth()); 2163 mWindowAlignment.vertical.setSize(getHeight()); 2164 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 2165 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 2166 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 2167 mScrollOffsetPrimary = -mWindowAlignment.mainAxis().getPaddingLow(); 2168 mScrollOffsetSecondary = -mWindowAlignment.secondAxis().getPaddingLow(); 2169 2170 if (DEBUG) { 2171 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 2172 + " mWindowAlignment " + mWindowAlignment 2173 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 2174 } 2175 } 2176 2177 private void updateScrollController() { 2178 // mScrollOffsetPrimary and mScrollOffsetSecondary includes the padding. 2179 // e.g. when topPadding is 16 for horizontal grid view, the initial 2180 // mScrollOffsetSecondary is -16. fastRelayout() put views based on offsets(not padding), 2181 // when padding changes to 20, we also need update mScrollOffsetSecondary to -20 before 2182 // fastRelayout() is performed 2183 int paddingPrimaryDiff, paddingSecondaryDiff; 2184 if (mOrientation == HORIZONTAL) { 2185 paddingPrimaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 2186 paddingSecondaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 2187 } else { 2188 paddingPrimaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 2189 paddingSecondaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 2190 } 2191 mScrollOffsetPrimary -= paddingPrimaryDiff; 2192 mScrollOffsetSecondary -= paddingSecondaryDiff; 2193 2194 mWindowAlignment.horizontal.setSize(getWidth()); 2195 mWindowAlignment.vertical.setSize(getHeight()); 2196 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 2197 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 2198 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 2199 2200 if (DEBUG) { 2201 Log.v(getTag(), "updateScrollController mSizePrimary " + mSizePrimary 2202 + " mWindowAlignment " + mWindowAlignment 2203 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 2204 } 2205 } 2206 2207 @Override 2208 public void scrollToPosition(int position) { 2209 setSelection(position, 0, false, 0); 2210 } 2211 2212 public void setSelection(int position, 2213 int primaryScrollExtra) { 2214 setSelection(position, 0, false, primaryScrollExtra); 2215 } 2216 2217 public void setSelectionSmooth(int position) { 2218 setSelection(position, 0, true, 0); 2219 } 2220 2221 public void setSelectionWithSub(int position, int subposition, 2222 int primaryScrollExtra) { 2223 setSelection(position, subposition, false, primaryScrollExtra); 2224 } 2225 2226 public void setSelectionSmoothWithSub(int position, int subposition) { 2227 setSelection(position, subposition, true, 0); 2228 } 2229 2230 public int getSelection() { 2231 return mFocusPosition; 2232 } 2233 2234 public int getSubSelection() { 2235 return mSubFocusPosition; 2236 } 2237 2238 public void setSelection(int position, int subposition, boolean smooth, 2239 int primaryScrollExtra) { 2240 if (mFocusPosition != position && position != NO_POSITION 2241 || subposition != mSubFocusPosition || primaryScrollExtra != mPrimaryScrollExtra) { 2242 scrollToSelection(position, subposition, smooth, primaryScrollExtra); 2243 } 2244 } 2245 2246 private void scrollToSelection(int position, int subposition, 2247 boolean smooth, int primaryScrollExtra) { 2248 if (TRACE) TraceHelper.beginSection("scrollToSelection"); 2249 mPrimaryScrollExtra = primaryScrollExtra; 2250 View view = findViewByPosition(position); 2251 if (view != null) { 2252 mInSelection = true; 2253 scrollToView(view, smooth); 2254 mInSelection = false; 2255 } else { 2256 mFocusPosition = position; 2257 mSubFocusPosition = subposition; 2258 mFocusPositionOffset = Integer.MIN_VALUE; 2259 if (!mLayoutEnabled) { 2260 return; 2261 } 2262 if (smooth) { 2263 if (!hasDoneFirstLayout()) { 2264 Log.w(getTag(), "setSelectionSmooth should " + 2265 "not be called before first layout pass"); 2266 return; 2267 } 2268 startPositionSmoothScroller(position); 2269 } else { 2270 mForceFullLayout = true; 2271 requestLayout(); 2272 } 2273 } 2274 if (TRACE) TraceHelper.endSection(); 2275 } 2276 2277 void startPositionSmoothScroller(int position) { 2278 LinearSmoothScroller linearSmoothScroller = new GridLinearSmoothScroller() { 2279 @Override 2280 public PointF computeScrollVectorForPosition(int targetPosition) { 2281 if (getChildCount() == 0) { 2282 return null; 2283 } 2284 final int firstChildPos = getPosition(getChildAt(0)); 2285 // TODO We should be able to deduce direction from bounds of current and target 2286 // focus, rather than making assumptions about positions and directionality 2287 final boolean isStart = mReverseFlowPrimary ? targetPosition > firstChildPos 2288 : targetPosition < firstChildPos; 2289 final int direction = isStart ? -1 : 1; 2290 if (mOrientation == HORIZONTAL) { 2291 return new PointF(direction, 0); 2292 } else { 2293 return new PointF(0, direction); 2294 } 2295 } 2296 2297 }; 2298 linearSmoothScroller.setTargetPosition(position); 2299 startSmoothScroll(linearSmoothScroller); 2300 } 2301 2302 private void processPendingMovement(boolean forward) { 2303 if (forward ? hasCreatedLastItem() : hasCreatedFirstItem()) { 2304 return; 2305 } 2306 if (mPendingMoveSmoothScroller == null) { 2307 // Stop existing scroller and create a new PendingMoveSmoothScroller. 2308 mBaseGridView.stopScroll(); 2309 PendingMoveSmoothScroller linearSmoothScroller = new PendingMoveSmoothScroller( 2310 forward ? 1 : -1, mNumRows > 1); 2311 mFocusPositionOffset = 0; 2312 startSmoothScroll(linearSmoothScroller); 2313 if (linearSmoothScroller.isRunning()) { 2314 mPendingMoveSmoothScroller = linearSmoothScroller; 2315 } 2316 } else { 2317 if (forward) { 2318 mPendingMoveSmoothScroller.increasePendingMoves(); 2319 } else { 2320 mPendingMoveSmoothScroller.decreasePendingMoves(); 2321 } 2322 } 2323 } 2324 2325 @Override 2326 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 2327 if (DEBUG) Log.v(getTag(), "onItemsAdded positionStart " 2328 + positionStart + " itemCount " + itemCount); 2329 if (mFocusPosition != NO_POSITION && mGrid != null && mGrid.getFirstVisibleIndex() >= 0 2330 && mFocusPositionOffset != Integer.MIN_VALUE) { 2331 int pos = mFocusPosition + mFocusPositionOffset; 2332 if (positionStart <= pos) { 2333 mFocusPositionOffset += itemCount; 2334 } 2335 } 2336 mChildrenStates.clear(); 2337 } 2338 2339 @Override 2340 public void onItemsChanged(RecyclerView recyclerView) { 2341 if (DEBUG) Log.v(getTag(), "onItemsChanged"); 2342 mFocusPositionOffset = 0; 2343 mChildrenStates.clear(); 2344 } 2345 2346 @Override 2347 public void onItemsRemoved(RecyclerView recyclerView, int positionStart, int itemCount) { 2348 if (DEBUG) Log.v(getTag(), "onItemsRemoved positionStart " 2349 + positionStart + " itemCount " + itemCount); 2350 if (mFocusPosition != NO_POSITION && mGrid != null && mGrid.getFirstVisibleIndex() >= 0 2351 && mFocusPositionOffset != Integer.MIN_VALUE) { 2352 int pos = mFocusPosition + mFocusPositionOffset; 2353 if (positionStart <= pos) { 2354 if (positionStart + itemCount > pos) { 2355 // stop updating offset after the focus item was removed 2356 mFocusPositionOffset = Integer.MIN_VALUE; 2357 } else { 2358 mFocusPositionOffset -= itemCount; 2359 } 2360 } 2361 } 2362 mChildrenStates.clear(); 2363 } 2364 2365 @Override 2366 public void onItemsMoved(RecyclerView recyclerView, int fromPosition, int toPosition, 2367 int itemCount) { 2368 if (DEBUG) Log.v(getTag(), "onItemsMoved fromPosition " 2369 + fromPosition + " toPosition " + toPosition); 2370 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2371 int pos = mFocusPosition + mFocusPositionOffset; 2372 if (fromPosition <= pos && pos < fromPosition + itemCount) { 2373 // moved items include focused position 2374 mFocusPositionOffset += toPosition - fromPosition; 2375 } else if (fromPosition < pos && toPosition > pos - itemCount) { 2376 // move items before focus position to after focused position 2377 mFocusPositionOffset -= itemCount; 2378 } else if (fromPosition > pos && toPosition < pos) { 2379 // move items after focus position to before focused position 2380 mFocusPositionOffset += itemCount; 2381 } 2382 } 2383 mChildrenStates.clear(); 2384 } 2385 2386 @Override 2387 public void onItemsUpdated(RecyclerView recyclerView, int positionStart, int itemCount) { 2388 if (DEBUG) Log.v(getTag(), "onItemsUpdated positionStart " 2389 + positionStart + " itemCount " + itemCount); 2390 for (int i = positionStart, end = positionStart + itemCount; i < end; i++) { 2391 mChildrenStates.remove(i); 2392 } 2393 } 2394 2395 @Override 2396 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 2397 if (mFocusSearchDisabled) { 2398 return true; 2399 } 2400 if (getPositionByView(child) == NO_POSITION) { 2401 // This shouldn't happen, but in case it does be sure not to attempt a 2402 // scroll to a view whose item has been removed. 2403 return true; 2404 } 2405 if (!mInLayout && !mInSelection && !mInScroll) { 2406 scrollToView(child, focused, true); 2407 } 2408 return true; 2409 } 2410 2411 @Override 2412 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 2413 boolean immediate) { 2414 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 2415 return false; 2416 } 2417 2418 int getScrollOffsetX() { 2419 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 2420 } 2421 2422 int getScrollOffsetY() { 2423 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 2424 } 2425 2426 public void getViewSelectedOffsets(View view, int[] offsets) { 2427 if (mOrientation == HORIZONTAL) { 2428 offsets[0] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2429 offsets[1] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2430 } else { 2431 offsets[1] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2432 offsets[0] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2433 } 2434 } 2435 2436 private int getPrimarySystemScrollPosition(View view) { 2437 final int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 2438 final int viewMin = getViewMin(view); 2439 final int viewMax = getViewMax(view); 2440 // TODO: change to use State object in onRequestChildFocus() 2441 boolean isMin, isMax; 2442 if (!mReverseFlowPrimary) { 2443 isMin = mGrid.getFirstVisibleIndex() == 0; 2444 isMax = mGrid.getLastVisibleIndex() == (mState == null ? 2445 getItemCount() : mState.getItemCount()) - 1; 2446 } else { 2447 isMax = mGrid.getFirstVisibleIndex() == 0; 2448 isMin = mGrid.getLastVisibleIndex() == (mState == null ? 2449 getItemCount() : mState.getItemCount()) - 1; 2450 } 2451 for (int i = getChildCount() - 1; (isMin || isMax) && i >= 0; i--) { 2452 View v = getChildAt(i); 2453 if (v == view || v == null) { 2454 continue; 2455 } 2456 if (isMin && getViewMin(v) < viewMin) { 2457 isMin = false; 2458 } 2459 if (isMax && getViewMax(v) > viewMax) { 2460 isMax = false; 2461 } 2462 } 2463 return mWindowAlignment.mainAxis().getSystemScrollPos(viewCenterPrimary, isMin, isMax); 2464 } 2465 2466 private int getPrimarySystemScrollPositionOfChildMax(View view) { 2467 int scrollPosition = getPrimarySystemScrollPosition(view); 2468 final LayoutParams lp = (LayoutParams) view.getLayoutParams(); 2469 int[] multipleAligns = lp.getAlignMultiple(); 2470 if (multipleAligns != null && multipleAligns.length > 0) { 2471 scrollPosition += multipleAligns[multipleAligns.length - 1] - multipleAligns[0]; 2472 } 2473 return scrollPosition; 2474 } 2475 2476 /** 2477 * Get adjusted primary position for a given childView (if there is multiple ItemAlignment defined 2478 * on the view). 2479 */ 2480 private int getAdjustedPrimaryScrollPosition(int scrollPrimary, View view, View childView) { 2481 int subindex = getSubPositionByView(view, childView); 2482 if (subindex != 0) { 2483 final LayoutParams lp = (LayoutParams) view.getLayoutParams(); 2484 scrollPrimary += lp.getAlignMultiple()[subindex] - lp.getAlignMultiple()[0]; 2485 } 2486 return scrollPrimary; 2487 } 2488 2489 private int getSecondarySystemScrollPosition(View view) { 2490 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 2491 int pos = getPositionByView(view); 2492 Grid.Location location = mGrid.getLocation(pos); 2493 final int row = location.row; 2494 final boolean isMin, isMax; 2495 if (!mReverseFlowSecondary) { 2496 isMin = row == 0; 2497 isMax = row == mGrid.getNumRows() - 1; 2498 } else { 2499 isMax = row == 0; 2500 isMin = row == mGrid.getNumRows() - 1; 2501 } 2502 return mWindowAlignment.secondAxis().getSystemScrollPos(viewCenterSecondary, isMin, isMax); 2503 } 2504 2505 /** 2506 * Scroll to a given child view and change mFocusPosition. 2507 */ 2508 private void scrollToView(View view, boolean smooth) { 2509 scrollToView(view, view == null ? null : view.findFocus(), smooth); 2510 } 2511 2512 /** 2513 * Scroll to a given child view and change mFocusPosition. 2514 */ 2515 private void scrollToView(View view, View childView, boolean smooth) { 2516 int newFocusPosition = getPositionByView(view); 2517 int newSubFocusPosition = getSubPositionByView(view, childView); 2518 if (newFocusPosition != mFocusPosition || newSubFocusPosition != mSubFocusPosition) { 2519 mFocusPosition = newFocusPosition; 2520 mSubFocusPosition = newSubFocusPosition; 2521 mFocusPositionOffset = 0; 2522 if (!mInLayout) { 2523 dispatchChildSelected(); 2524 } 2525 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 2526 mBaseGridView.invalidate(); 2527 } 2528 } 2529 if (view == null) { 2530 return; 2531 } 2532 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 2533 // transfer focus to the child if it does not have focus yet (e.g. triggered 2534 // by setSelection()) 2535 view.requestFocus(); 2536 } 2537 if (!mScrollEnabled && smooth) { 2538 return; 2539 } 2540 if (getScrollPosition(view, childView, sTwoInts)) { 2541 scrollGrid(sTwoInts[0], sTwoInts[1], smooth); 2542 } 2543 } 2544 2545 private boolean getScrollPosition(View view, View childView, int[] deltas) { 2546 switch (mFocusScrollStrategy) { 2547 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2548 default: 2549 return getAlignedPosition(view, childView, deltas); 2550 case BaseGridView.FOCUS_SCROLL_ITEM: 2551 case BaseGridView.FOCUS_SCROLL_PAGE: 2552 return getNoneAlignedPosition(view, deltas); 2553 } 2554 } 2555 2556 private boolean getNoneAlignedPosition(View view, int[] deltas) { 2557 int pos = getPositionByView(view); 2558 int viewMin = getViewMin(view); 2559 int viewMax = getViewMax(view); 2560 // we either align "firstView" to left/top padding edge 2561 // or align "lastView" to right/bottom padding edge 2562 View firstView = null; 2563 View lastView = null; 2564 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 2565 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 2566 final int row = mGrid.getRowIndex(pos); 2567 if (viewMin < paddingLow) { 2568 // view enters low padding area: 2569 firstView = view; 2570 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2571 // scroll one "page" left/top, 2572 // align first visible item of the "page" at the low padding edge. 2573 while (prependOneColumnVisibleItems()) { 2574 CircularIntArray positions = 2575 mGrid.getItemPositionsInRows(mGrid.getFirstVisibleIndex(), pos)[row]; 2576 firstView = findViewByPosition(positions.get(0)); 2577 if (viewMax - getViewMin(firstView) > clientSize) { 2578 if (positions.size() > 2) { 2579 firstView = findViewByPosition(positions.get(2)); 2580 } 2581 break; 2582 } 2583 } 2584 } 2585 } else if (viewMax > clientSize + paddingLow) { 2586 // view enters high padding area: 2587 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2588 // scroll whole one page right/bottom, align view at the low padding edge. 2589 firstView = view; 2590 do { 2591 CircularIntArray positions = 2592 mGrid.getItemPositionsInRows(pos, mGrid.getLastVisibleIndex())[row]; 2593 lastView = findViewByPosition(positions.get(positions.size() - 1)); 2594 if (getViewMax(lastView) - viewMin > clientSize) { 2595 lastView = null; 2596 break; 2597 } 2598 } while (appendOneColumnVisibleItems()); 2599 if (lastView != null) { 2600 // however if we reached end, we should align last view. 2601 firstView = null; 2602 } 2603 } else { 2604 lastView = view; 2605 } 2606 } 2607 int scrollPrimary = 0; 2608 int scrollSecondary = 0; 2609 if (firstView != null) { 2610 scrollPrimary = getViewMin(firstView) - paddingLow; 2611 } else if (lastView != null) { 2612 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 2613 } 2614 View secondaryAlignedView; 2615 if (firstView != null) { 2616 secondaryAlignedView = firstView; 2617 } else if (lastView != null) { 2618 secondaryAlignedView = lastView; 2619 } else { 2620 secondaryAlignedView = view; 2621 } 2622 scrollSecondary = getSecondarySystemScrollPosition(secondaryAlignedView); 2623 scrollSecondary -= mScrollOffsetSecondary; 2624 if (scrollPrimary != 0 || scrollSecondary != 0) { 2625 deltas[0] = scrollPrimary; 2626 deltas[1] = scrollSecondary; 2627 return true; 2628 } 2629 return false; 2630 } 2631 2632 private boolean getAlignedPosition(View view, View childView, int[] deltas) { 2633 int scrollPrimary = getPrimarySystemScrollPosition(view); 2634 if (childView != null) { 2635 scrollPrimary = getAdjustedPrimaryScrollPosition(scrollPrimary, view, childView); 2636 } 2637 int scrollSecondary = getSecondarySystemScrollPosition(view); 2638 if (DEBUG) { 2639 Log.v(getTag(), "getAlignedPosition " + scrollPrimary + " " + scrollSecondary 2640 + " " + mPrimaryScrollExtra + " " + mWindowAlignment); 2641 Log.v(getTag(), "getAlignedPosition " + mScrollOffsetPrimary + " " + mScrollOffsetSecondary); 2642 } 2643 scrollPrimary -= mScrollOffsetPrimary; 2644 scrollSecondary -= mScrollOffsetSecondary; 2645 scrollPrimary += mPrimaryScrollExtra; 2646 if (scrollPrimary != 0 || scrollSecondary != 0) { 2647 deltas[0] = scrollPrimary; 2648 deltas[1] = scrollSecondary; 2649 return true; 2650 } 2651 return false; 2652 } 2653 2654 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 2655 if (mInLayout) { 2656 scrollDirectionPrimary(scrollPrimary); 2657 scrollDirectionSecondary(scrollSecondary); 2658 } else { 2659 int scrollX; 2660 int scrollY; 2661 if (mOrientation == HORIZONTAL) { 2662 scrollX = scrollPrimary; 2663 scrollY = scrollSecondary; 2664 } else { 2665 scrollX = scrollSecondary; 2666 scrollY = scrollPrimary; 2667 } 2668 if (smooth) { 2669 mBaseGridView.smoothScrollBy(scrollX, scrollY); 2670 } else { 2671 mBaseGridView.scrollBy(scrollX, scrollY); 2672 } 2673 } 2674 } 2675 2676 public void setPruneChild(boolean pruneChild) { 2677 if (mPruneChild != pruneChild) { 2678 mPruneChild = pruneChild; 2679 if (mPruneChild) { 2680 requestLayout(); 2681 } 2682 } 2683 } 2684 2685 public boolean getPruneChild() { 2686 return mPruneChild; 2687 } 2688 2689 public void setScrollEnabled(boolean scrollEnabled) { 2690 if (mScrollEnabled != scrollEnabled) { 2691 mScrollEnabled = scrollEnabled; 2692 if (mScrollEnabled && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED 2693 && mFocusPosition != NO_POSITION) { 2694 scrollToSelection(mFocusPosition, mSubFocusPosition, 2695 true, mPrimaryScrollExtra); 2696 } 2697 } 2698 } 2699 2700 public boolean isScrollEnabled() { 2701 return mScrollEnabled; 2702 } 2703 2704 private int findImmediateChildIndex(View view) { 2705 if (mBaseGridView != null && view != mBaseGridView) { 2706 view = findContainingItemView(view); 2707 if (view != null) { 2708 for (int i = 0, count = getChildCount(); i < count; i++) { 2709 if (getChildAt(i) == view) { 2710 return i; 2711 } 2712 } 2713 } 2714 } 2715 return NO_POSITION; 2716 } 2717 2718 void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) { 2719 if (gainFocus) { 2720 // if gridview.requestFocus() is called, select first focusable child. 2721 for (int i = mFocusPosition; ;i++) { 2722 View view = findViewByPosition(i); 2723 if (view == null) { 2724 break; 2725 } 2726 if (view.getVisibility() == View.VISIBLE && view.hasFocusable()) { 2727 view.requestFocus(); 2728 break; 2729 } 2730 } 2731 } 2732 } 2733 2734 void setFocusSearchDisabled(boolean disabled) { 2735 mFocusSearchDisabled = disabled; 2736 } 2737 2738 boolean isFocusSearchDisabled() { 2739 return mFocusSearchDisabled; 2740 } 2741 2742 @Override 2743 public View onInterceptFocusSearch(View focused, int direction) { 2744 if (mFocusSearchDisabled) { 2745 return focused; 2746 } 2747 2748 final FocusFinder ff = FocusFinder.getInstance(); 2749 View result = null; 2750 if (direction == View.FOCUS_FORWARD || direction == View.FOCUS_BACKWARD) { 2751 // convert direction to absolute direction and see if we have a view there and if not 2752 // tell LayoutManager to add if it can. 2753 if (canScrollVertically()) { 2754 final int absDir = 2755 direction == View.FOCUS_FORWARD ? View.FOCUS_DOWN : View.FOCUS_UP; 2756 result = ff.findNextFocus(mBaseGridView, focused, absDir); 2757 } 2758 if (canScrollHorizontally()) { 2759 boolean rtl = getLayoutDirection() == ViewCompat.LAYOUT_DIRECTION_RTL; 2760 final int absDir = (direction == View.FOCUS_FORWARD) ^ rtl 2761 ? View.FOCUS_RIGHT : View.FOCUS_LEFT; 2762 result = ff.findNextFocus(mBaseGridView, focused, absDir); 2763 } 2764 } else { 2765 result = ff.findNextFocus(mBaseGridView, focused, direction); 2766 } 2767 if (result != null) { 2768 return result; 2769 } 2770 2771 if (DEBUG) Log.v(getTag(), "regular focusSearch failed direction " + direction); 2772 int movement = getMovement(direction); 2773 final boolean isScroll = mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE; 2774 if (movement == NEXT_ITEM) { 2775 if (isScroll || !mFocusOutEnd) { 2776 result = focused; 2777 } 2778 if (mScrollEnabled && !hasCreatedLastItem()) { 2779 processPendingMovement(true); 2780 result = focused; 2781 } 2782 } else if (movement == PREV_ITEM) { 2783 if (isScroll || !mFocusOutFront) { 2784 result = focused; 2785 } 2786 if (mScrollEnabled && !hasCreatedFirstItem()) { 2787 processPendingMovement(false); 2788 result = focused; 2789 } 2790 } else if (movement == NEXT_ROW) { 2791 if (isScroll || !mFocusOutSideEnd) { 2792 result = focused; 2793 } 2794 } else if (movement == PREV_ROW) { 2795 if (isScroll || !mFocusOutSideStart) { 2796 result = focused; 2797 } 2798 } 2799 if (result != null) { 2800 return result; 2801 } 2802 2803 if (DEBUG) Log.v(getTag(), "now focusSearch in parent"); 2804 result = mBaseGridView.getParent().focusSearch(focused, direction); 2805 if (result != null) { 2806 return result; 2807 } 2808 return focused != null ? focused : mBaseGridView; 2809 } 2810 2811 boolean hasPreviousViewInSameRow(int pos) { 2812 if (mGrid == null || pos == NO_POSITION || mGrid.getFirstVisibleIndex() < 0) { 2813 return false; 2814 } 2815 if (mGrid.getFirstVisibleIndex() > 0) { 2816 return true; 2817 } 2818 final int focusedRow = mGrid.getLocation(pos).row; 2819 for (int i = getChildCount() - 1; i >= 0; i--) { 2820 int position = getPositionByIndex(i); 2821 Grid.Location loc = mGrid.getLocation(position); 2822 if (loc != null && loc.row == focusedRow) { 2823 if (position < pos) { 2824 return true; 2825 } 2826 } 2827 } 2828 return false; 2829 } 2830 2831 @Override 2832 public boolean onAddFocusables(RecyclerView recyclerView, 2833 ArrayList<View> views, int direction, int focusableMode) { 2834 if (mFocusSearchDisabled) { 2835 return true; 2836 } 2837 // If this viewgroup or one of its children currently has focus then we 2838 // consider our children for focus searching in main direction on the same row. 2839 // If this viewgroup has no focus and using focus align, we want the system 2840 // to ignore our children and pass focus to the viewgroup, which will pass 2841 // focus on to its children appropriately. 2842 // If this viewgroup has no focus and not using focus align, we want to 2843 // consider the child that does not overlap with padding area. 2844 if (recyclerView.hasFocus()) { 2845 if (mPendingMoveSmoothScroller != null) { 2846 // don't find next focusable if has pending movement. 2847 return true; 2848 } 2849 final int movement = getMovement(direction); 2850 final View focused = recyclerView.findFocus(); 2851 final int focusedIndex = findImmediateChildIndex(focused); 2852 final int focusedPos = getPositionByIndex(focusedIndex); 2853 // Add focusables of focused item. 2854 if (focusedPos != NO_POSITION) { 2855 findViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2856 } 2857 if (mGrid == null || getChildCount() == 0) { 2858 // no grid information, or no child, bail out. 2859 return true; 2860 } 2861 if ((movement == NEXT_ROW || movement == PREV_ROW) && mGrid.getNumRows() <= 1) { 2862 // For single row, cannot navigate to previous/next row. 2863 return true; 2864 } 2865 // Add focusables of neighbor depending on the focus search direction. 2866 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2867 mGrid.getLocation(focusedPos).row : NO_POSITION; 2868 final int focusableCount = views.size(); 2869 int inc = movement == NEXT_ITEM || movement == NEXT_ROW ? 1 : -1; 2870 int loop_end = inc > 0 ? getChildCount() - 1 : 0; 2871 int loop_start; 2872 if (focusedIndex == NO_POSITION) { 2873 loop_start = inc > 0 ? 0 : getChildCount() - 1; 2874 } else { 2875 loop_start = focusedIndex + inc; 2876 } 2877 for (int i = loop_start; inc > 0 ? i <= loop_end : i >= loop_end; i += inc) { 2878 final View child = getChildAt(i); 2879 if (child.getVisibility() != View.VISIBLE || !child.hasFocusable()) { 2880 continue; 2881 } 2882 // if there wasn't any focusing item, add the very first focusable 2883 // items and stop. 2884 if (focusedPos == NO_POSITION) { 2885 child.addFocusables(views, direction, focusableMode); 2886 if (views.size() > focusableCount) { 2887 break; 2888 } 2889 continue; 2890 } 2891 int position = getPositionByIndex(i); 2892 Grid.Location loc = mGrid.getLocation(position); 2893 if (loc == null) { 2894 continue; 2895 } 2896 if (movement == NEXT_ITEM) { 2897 // Add first focusable item on the same row 2898 if (loc.row == focusedRow && position > focusedPos) { 2899 child.addFocusables(views, direction, focusableMode); 2900 if (views.size() > focusableCount) { 2901 break; 2902 } 2903 } 2904 } else if (movement == PREV_ITEM) { 2905 // Add first focusable item on the same row 2906 if (loc.row == focusedRow && position < focusedPos) { 2907 child.addFocusables(views, direction, focusableMode); 2908 if (views.size() > focusableCount) { 2909 break; 2910 } 2911 } 2912 } else if (movement == NEXT_ROW) { 2913 // Add all focusable items after this item whose row index is bigger 2914 if (loc.row == focusedRow) { 2915 continue; 2916 } else if (loc.row < focusedRow) { 2917 break; 2918 } 2919 child.addFocusables(views, direction, focusableMode); 2920 } else if (movement == PREV_ROW) { 2921 // Add all focusable items before this item whose row index is smaller 2922 if (loc.row == focusedRow) { 2923 continue; 2924 } else if (loc.row > focusedRow) { 2925 break; 2926 } 2927 child.addFocusables(views, direction, focusableMode); 2928 } 2929 } 2930 } else { 2931 int focusableCount = views.size(); 2932 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2933 // adding views not overlapping padding area to avoid scrolling in gaining focus 2934 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2935 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2936 for (int i = 0, count = getChildCount(); i < count; i++) { 2937 View child = getChildAt(i); 2938 if (child.getVisibility() == View.VISIBLE) { 2939 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2940 child.addFocusables(views, direction, focusableMode); 2941 } 2942 } 2943 } 2944 // if we cannot find any, then just add all children. 2945 if (views.size() == focusableCount) { 2946 for (int i = 0, count = getChildCount(); i < count; i++) { 2947 View child = getChildAt(i); 2948 if (child.getVisibility() == View.VISIBLE) { 2949 child.addFocusables(views, direction, focusableMode); 2950 } 2951 } 2952 } 2953 } else { 2954 View view = findViewByPosition(mFocusPosition); 2955 if (view != null) { 2956 view.addFocusables(views, direction, focusableMode); 2957 } 2958 } 2959 // if still cannot find any, fall through and add itself 2960 if (views.size() != focusableCount) { 2961 return true; 2962 } 2963 if (recyclerView.isFocusable()) { 2964 views.add(recyclerView); 2965 } 2966 } 2967 return true; 2968 } 2969 2970 private boolean hasCreatedLastItem() { 2971 int count = getItemCount(); 2972 return count == 0 || mBaseGridView.findViewHolderForAdapterPosition(count - 1) != null; 2973 } 2974 2975 private boolean hasCreatedFirstItem() { 2976 int count = getItemCount(); 2977 return count == 0 || mBaseGridView.findViewHolderForAdapterPosition(0) != null; 2978 } 2979 2980 boolean canScrollTo(View view) { 2981 return view.getVisibility() == View.VISIBLE && (!hasFocus() || view.hasFocusable()); 2982 } 2983 2984 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2985 Rect previouslyFocusedRect) { 2986 switch (mFocusScrollStrategy) { 2987 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2988 default: 2989 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2990 direction, previouslyFocusedRect); 2991 case BaseGridView.FOCUS_SCROLL_PAGE: 2992 case BaseGridView.FOCUS_SCROLL_ITEM: 2993 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2994 direction, previouslyFocusedRect); 2995 } 2996 } 2997 2998 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2999 int direction, Rect previouslyFocusedRect) { 3000 View view = findViewByPosition(mFocusPosition); 3001 if (view != null) { 3002 boolean result = view.requestFocus(direction, previouslyFocusedRect); 3003 if (!result && DEBUG) { 3004 Log.w(getTag(), "failed to request focus on " + view); 3005 } 3006 return result; 3007 } 3008 return false; 3009 } 3010 3011 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 3012 int direction, Rect previouslyFocusedRect) { 3013 // focus to view not overlapping padding area to avoid scrolling in gaining focus 3014 int index; 3015 int increment; 3016 int end; 3017 int count = getChildCount(); 3018 if ((direction & View.FOCUS_FORWARD) != 0) { 3019 index = 0; 3020 increment = 1; 3021 end = count; 3022 } else { 3023 index = count - 1; 3024 increment = -1; 3025 end = -1; 3026 } 3027 int left = mWindowAlignment.mainAxis().getPaddingLow(); 3028 int right = mWindowAlignment.mainAxis().getClientSize() + left; 3029 for (int i = index; i != end; i += increment) { 3030 View child = getChildAt(i); 3031 if (child.getVisibility() == View.VISIBLE) { 3032 if (getViewMin(child) >= left && getViewMax(child) <= right) { 3033 if (child.requestFocus(direction, previouslyFocusedRect)) { 3034 return true; 3035 } 3036 } 3037 } 3038 } 3039 return false; 3040 } 3041 3042 private final static int PREV_ITEM = 0; 3043 private final static int NEXT_ITEM = 1; 3044 private final static int PREV_ROW = 2; 3045 private final static int NEXT_ROW = 3; 3046 3047 private int getMovement(int direction) { 3048 int movement = View.FOCUS_LEFT; 3049 3050 if (mOrientation == HORIZONTAL) { 3051 switch(direction) { 3052 case View.FOCUS_LEFT: 3053 movement = (!mReverseFlowPrimary) ? PREV_ITEM : NEXT_ITEM; 3054 break; 3055 case View.FOCUS_RIGHT: 3056 movement = (!mReverseFlowPrimary) ? NEXT_ITEM : PREV_ITEM; 3057 break; 3058 case View.FOCUS_UP: 3059 movement = PREV_ROW; 3060 break; 3061 case View.FOCUS_DOWN: 3062 movement = NEXT_ROW; 3063 break; 3064 } 3065 } else if (mOrientation == VERTICAL) { 3066 switch(direction) { 3067 case View.FOCUS_LEFT: 3068 movement = (!mReverseFlowSecondary) ? PREV_ROW : NEXT_ROW; 3069 break; 3070 case View.FOCUS_RIGHT: 3071 movement = (!mReverseFlowSecondary) ? NEXT_ROW : PREV_ROW; 3072 break; 3073 case View.FOCUS_UP: 3074 movement = PREV_ITEM; 3075 break; 3076 case View.FOCUS_DOWN: 3077 movement = NEXT_ITEM; 3078 break; 3079 } 3080 } 3081 3082 return movement; 3083 } 3084 3085 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 3086 View view = findViewByPosition(mFocusPosition); 3087 if (view == null) { 3088 return i; 3089 } 3090 int focusIndex = recyclerView.indexOfChild(view); 3091 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 3092 // drawing order is 0 1 2 3 9 8 7 6 5 4 3093 if (i < focusIndex) { 3094 return i; 3095 } else if (i < childCount - 1) { 3096 return focusIndex + childCount - 1 - i; 3097 } else { 3098 return focusIndex; 3099 } 3100 } 3101 3102 @Override 3103 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 3104 RecyclerView.Adapter newAdapter) { 3105 if (DEBUG) Log.v(getTag(), "onAdapterChanged to " + newAdapter); 3106 if (oldAdapter != null) { 3107 discardLayoutInfo(); 3108 mFocusPosition = NO_POSITION; 3109 mFocusPositionOffset = 0; 3110 mChildrenStates.clear(); 3111 } 3112 if (newAdapter instanceof FacetProviderAdapter) { 3113 mFacetProviderAdapter = (FacetProviderAdapter) newAdapter; 3114 } else { 3115 mFacetProviderAdapter = null; 3116 } 3117 super.onAdapterChanged(oldAdapter, newAdapter); 3118 } 3119 3120 private void discardLayoutInfo() { 3121 mGrid = null; 3122 mRowSizeSecondary = null; 3123 mRowSecondarySizeRefresh = false; 3124 } 3125 3126 public void setLayoutEnabled(boolean layoutEnabled) { 3127 if (mLayoutEnabled != layoutEnabled) { 3128 mLayoutEnabled = layoutEnabled; 3129 requestLayout(); 3130 } 3131 } 3132 3133 void setChildrenVisibility(int visibility) { 3134 mChildVisibility = visibility; 3135 if (mChildVisibility != -1) { 3136 int count = getChildCount(); 3137 for (int i= 0; i < count; i++) { 3138 getChildAt(i).setVisibility(mChildVisibility); 3139 } 3140 } 3141 } 3142 3143 final static class SavedState implements Parcelable { 3144 3145 int index; // index inside adapter of the current view 3146 Bundle childStates = Bundle.EMPTY; 3147 3148 @Override 3149 public void writeToParcel(Parcel out, int flags) { 3150 out.writeInt(index); 3151 out.writeBundle(childStates); 3152 } 3153 3154 @SuppressWarnings("hiding") 3155 public static final Parcelable.Creator<SavedState> CREATOR = 3156 new Parcelable.Creator<SavedState>() { 3157 @Override 3158 public SavedState createFromParcel(Parcel in) { 3159 return new SavedState(in); 3160 } 3161 3162 @Override 3163 public SavedState[] newArray(int size) { 3164 return new SavedState[size]; 3165 } 3166 }; 3167 3168 @Override 3169 public int describeContents() { 3170 return 0; 3171 } 3172 3173 SavedState(Parcel in) { 3174 index = in.readInt(); 3175 childStates = in.readBundle(GridLayoutManager.class.getClassLoader()); 3176 } 3177 3178 SavedState() { 3179 } 3180 } 3181 3182 @Override 3183 public Parcelable onSaveInstanceState() { 3184 if (DEBUG) Log.v(getTag(), "onSaveInstanceState getSelection() " + getSelection()); 3185 SavedState ss = new SavedState(); 3186 // save selected index 3187 ss.index = getSelection(); 3188 // save offscreen child (state when they are recycled) 3189 Bundle bundle = mChildrenStates.saveAsBundle(); 3190 // save views currently is on screen (TODO save cached views) 3191 for (int i = 0, count = getChildCount(); i < count; i++) { 3192 View view = getChildAt(i); 3193 int position = getPositionByView(view); 3194 if (position != NO_POSITION) { 3195 bundle = mChildrenStates.saveOnScreenView(bundle, view, position); 3196 } 3197 } 3198 ss.childStates = bundle; 3199 return ss; 3200 } 3201 3202 void onChildRecycled(RecyclerView.ViewHolder holder) { 3203 final int position = holder.getAdapterPosition(); 3204 if (position != NO_POSITION) { 3205 mChildrenStates.saveOffscreenView(holder.itemView, position); 3206 } 3207 } 3208 3209 @Override 3210 public void onRestoreInstanceState(Parcelable state) { 3211 if (!(state instanceof SavedState)) { 3212 return; 3213 } 3214 SavedState loadingState = (SavedState)state; 3215 mFocusPosition = loadingState.index; 3216 mFocusPositionOffset = 0; 3217 mChildrenStates.loadFromBundle(loadingState.childStates); 3218 mForceFullLayout = true; 3219 requestLayout(); 3220 if (DEBUG) Log.v(getTag(), "onRestoreInstanceState mFocusPosition " + mFocusPosition); 3221 } 3222 3223 @Override 3224 public int getRowCountForAccessibility(RecyclerView.Recycler recycler, 3225 RecyclerView.State state) { 3226 if (mOrientation == HORIZONTAL && mGrid != null) { 3227 return mGrid.getNumRows(); 3228 } 3229 return super.getRowCountForAccessibility(recycler, state); 3230 } 3231 3232 @Override 3233 public int getColumnCountForAccessibility(RecyclerView.Recycler recycler, 3234 RecyclerView.State state) { 3235 if (mOrientation == VERTICAL && mGrid != null) { 3236 return mGrid.getNumRows(); 3237 } 3238 return super.getColumnCountForAccessibility(recycler, state); 3239 } 3240 3241 @Override 3242 public void onInitializeAccessibilityNodeInfoForItem(RecyclerView.Recycler recycler, 3243 RecyclerView.State state, View host, AccessibilityNodeInfoCompat info) { 3244 ViewGroup.LayoutParams lp = host.getLayoutParams(); 3245 if (mGrid == null || !(lp instanceof LayoutParams)) { 3246 super.onInitializeAccessibilityNodeInfoForItem(recycler, state, host, info); 3247 return; 3248 } 3249 LayoutParams glp = (LayoutParams) lp; 3250 int position = glp.getViewLayoutPosition(); 3251 int rowIndex = mGrid.getRowIndex(position); 3252 int guessSpanIndex = position / mGrid.getNumRows(); 3253 if (mOrientation == HORIZONTAL) { 3254 info.setCollectionItemInfo(AccessibilityNodeInfoCompat.CollectionItemInfoCompat.obtain( 3255 rowIndex, 1, guessSpanIndex, 1, false, false)); 3256 } else { 3257 info.setCollectionItemInfo(AccessibilityNodeInfoCompat.CollectionItemInfoCompat.obtain( 3258 guessSpanIndex, 1, rowIndex, 1, false, false)); 3259 } 3260 } 3261 3262 /* 3263 * Leanback widget is different than the default implementation because the "scroll" is driven 3264 * by selection change. 3265 */ 3266 @Override 3267 public boolean performAccessibilityAction(Recycler recycler, State state, int action, 3268 Bundle args) { 3269 saveContext(recycler, state); 3270 switch (action) { 3271 case AccessibilityNodeInfoCompat.ACTION_SCROLL_BACKWARD: 3272 // try to focus all the way to the last visible item on the same row. 3273 processSelectionMoves(false, -mState.getItemCount()); 3274 break; 3275 case AccessibilityNodeInfoCompat.ACTION_SCROLL_FORWARD: 3276 processSelectionMoves(false, mState.getItemCount()); 3277 break; 3278 } 3279 leaveContext(); 3280 return true; 3281 } 3282 3283 /* 3284 * Move mFocusPosition multiple steps on the same row in main direction. 3285 * Stops when moves are all consumed or reach first/last visible item. 3286 * Returning remaining moves. 3287 */ 3288 private int processSelectionMoves(boolean preventScroll, int moves) { 3289 if (mGrid == null) { 3290 return moves; 3291 } 3292 int focusPosition = mFocusPosition; 3293 int focusedRow = focusPosition != NO_POSITION ? 3294 mGrid.getRowIndex(focusPosition) : NO_POSITION; 3295 View newSelected = null; 3296 for (int i = 0, count = getChildCount(); i < count && moves != 0; i++) { 3297 int index = moves > 0 ? i : count - 1 - i; 3298 final View child = getChildAt(index); 3299 if (!canScrollTo(child)) { 3300 continue; 3301 } 3302 int position = getPositionByIndex(index); 3303 int rowIndex = mGrid.getRowIndex(position); 3304 if (focusedRow == NO_POSITION) { 3305 focusPosition = position; 3306 newSelected = child; 3307 focusedRow = rowIndex; 3308 } else if (rowIndex == focusedRow) { 3309 if ((moves > 0 && position > focusPosition) 3310 || (moves < 0 && position < focusPosition)) { 3311 focusPosition = position; 3312 newSelected = child; 3313 if (moves > 0) { 3314 moves--; 3315 } else { 3316 moves++; 3317 } 3318 } 3319 } 3320 } 3321 if (newSelected != null) { 3322 if (preventScroll) { 3323 if (hasFocus()) { 3324 mInSelection = true; 3325 newSelected.requestFocus(); 3326 mInSelection = false; 3327 } 3328 mFocusPosition = focusPosition; 3329 mSubFocusPosition = 0; 3330 } else { 3331 scrollToView(newSelected, true); 3332 } 3333 } 3334 return moves; 3335 } 3336 3337 @Override 3338 public void onInitializeAccessibilityNodeInfo(Recycler recycler, State state, 3339 AccessibilityNodeInfoCompat info) { 3340 saveContext(recycler, state); 3341 if (mScrollEnabled && !hasCreatedFirstItem()) { 3342 info.addAction(AccessibilityNodeInfoCompat.ACTION_SCROLL_BACKWARD); 3343 info.setScrollable(true); 3344 } 3345 if (mScrollEnabled && !hasCreatedLastItem()) { 3346 info.addAction(AccessibilityNodeInfoCompat.ACTION_SCROLL_FORWARD); 3347 info.setScrollable(true); 3348 } 3349 final AccessibilityNodeInfoCompat.CollectionInfoCompat collectionInfo 3350 = AccessibilityNodeInfoCompat.CollectionInfoCompat 3351 .obtain(getRowCountForAccessibility(recycler, state), 3352 getColumnCountForAccessibility(recycler, state), 3353 isLayoutHierarchical(recycler, state), 3354 getSelectionModeForAccessibility(recycler, state)); 3355 info.setCollectionInfo(collectionInfo); 3356 leaveContext(); 3357 } 3358} 3359