GridLayoutManager.java revision 3a7aa9cd68bd39f3a843291817dc209d1d9a45aa
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.v7.widget.LinearSmoothScroller; 25import android.support.v7.widget.RecyclerView; 26import android.support.v7.widget.RecyclerView.Recycler; 27import android.support.v7.widget.RecyclerView.State; 28import android.support.v17.leanback.os.TraceHelper; 29 30import static android.support.v7.widget.RecyclerView.NO_ID; 31import static android.support.v7.widget.RecyclerView.NO_POSITION; 32import static android.support.v7.widget.RecyclerView.HORIZONTAL; 33import static android.support.v7.widget.RecyclerView.VERTICAL; 34 35import android.util.AttributeSet; 36import android.util.Log; 37import android.view.FocusFinder; 38import android.view.Gravity; 39import android.view.View; 40import android.view.ViewParent; 41import android.view.View.MeasureSpec; 42import android.view.ViewGroup.MarginLayoutParams; 43import android.view.ViewGroup; 44 45import java.io.PrintWriter; 46import java.io.StringWriter; 47import java.util.ArrayList; 48import java.util.List; 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 static class LayoutParams extends RecyclerView.LayoutParams { 59 60 // The view is saved only during animation. 61 private View mView; 62 63 // For placement 64 private int mLeftInset; 65 private int mTopInset; 66 private int mRightInset; 67 private int mBottomInset; 68 69 // For alignment 70 private int mAlignX; 71 private int mAlignY; 72 73 public LayoutParams(Context c, AttributeSet attrs) { 74 super(c, attrs); 75 } 76 77 public LayoutParams(int width, int height) { 78 super(width, height); 79 } 80 81 public LayoutParams(MarginLayoutParams source) { 82 super(source); 83 } 84 85 public LayoutParams(ViewGroup.LayoutParams source) { 86 super(source); 87 } 88 89 public LayoutParams(RecyclerView.LayoutParams source) { 90 super(source); 91 } 92 93 public LayoutParams(LayoutParams source) { 94 super(source); 95 } 96 97 int getAlignX() { 98 return mAlignX; 99 } 100 101 int getAlignY() { 102 return mAlignY; 103 } 104 105 int getOpticalLeft(View view) { 106 return view.getLeft() + mLeftInset; 107 } 108 109 int getOpticalTop(View view) { 110 return view.getTop() + mTopInset; 111 } 112 113 int getOpticalRight(View view) { 114 return view.getRight() - mRightInset; 115 } 116 117 int getOpticalBottom(View view) { 118 return view.getBottom() - mBottomInset; 119 } 120 121 int getOpticalWidth(View view) { 122 return view.getWidth() - mLeftInset - mRightInset; 123 } 124 125 int getOpticalHeight(View view) { 126 return view.getHeight() - mTopInset - mBottomInset; 127 } 128 129 int getOpticalLeftInset() { 130 return mLeftInset; 131 } 132 133 int getOpticalRightInset() { 134 return mRightInset; 135 } 136 137 int getOpticalTopInset() { 138 return mTopInset; 139 } 140 141 int getOpticalBottomInset() { 142 return mBottomInset; 143 } 144 145 void setAlignX(int alignX) { 146 mAlignX = alignX; 147 } 148 149 void setAlignY(int alignY) { 150 mAlignY = alignY; 151 } 152 153 void setOpticalInsets(int leftInset, int topInset, int rightInset, int bottomInset) { 154 mLeftInset = leftInset; 155 mTopInset = topInset; 156 mRightInset = rightInset; 157 mBottomInset = bottomInset; 158 } 159 160 private void invalidateItemDecoration() { 161 ViewParent parent = mView.getParent(); 162 if (parent instanceof RecyclerView) { 163 // TODO: we only need invalidate parent if it has ItemDecoration 164 ((RecyclerView) parent).invalidate(); 165 } 166 } 167 } 168 169 /** 170 * Base class which scrolls to selected view in onStop(). 171 */ 172 abstract class GridLinearSmoothScroller extends LinearSmoothScroller { 173 GridLinearSmoothScroller() { 174 super(mBaseGridView.getContext()); 175 } 176 177 @Override 178 protected void onStop() { 179 // onTargetFound() may not be called if we hit the "wall" first. 180 View targetView = findViewByPosition(getTargetPosition()); 181 if (hasFocus() && targetView != null) { 182 mInSelection = true; 183 targetView.requestFocus(); 184 mInSelection = false; 185 } 186 if (needsDispatchChildSelectedOnStop()) { 187 dispatchChildSelected(); 188 } 189 super.onStop(); 190 } 191 192 boolean needsDispatchChildSelectedOnStop() { 193 return true; 194 } 195 196 @Override 197 protected void onTargetFound(View targetView, 198 RecyclerView.State state, Action action) { 199 if (getScrollPosition(targetView, sTwoInts)) { 200 int dx, dy; 201 if (mOrientation == HORIZONTAL) { 202 dx = sTwoInts[0]; 203 dy = sTwoInts[1]; 204 } else { 205 dx = sTwoInts[1]; 206 dy = sTwoInts[0]; 207 } 208 final int distance = (int) Math.sqrt(dx * dx + dy * dy); 209 final int time = calculateTimeForDeceleration(distance); 210 action.update(dx, dy, time, mDecelerateInterpolator); 211 } 212 } 213 } 214 215 /** 216 * The SmoothScroller that remembers pending DPAD keys and consume pending keys 217 * during scroll. 218 */ 219 final class PendingMoveSmoothScroller extends GridLinearSmoothScroller { 220 // -2 is a target position that LinearSmoothScroller can never find until 221 // consumePendingMovesXXX() sets real targetPosition. 222 final static int TARGET_UNDEFINED = -2; 223 // whether the grid is staggered. 224 private final boolean mStaggeredGrid; 225 // Number of pending movements on primary direction, negative if PREV_ITEM. 226 private int mPendingMoves; 227 228 PendingMoveSmoothScroller(int initialPendingMoves, boolean staggeredGrid) { 229 mPendingMoves = initialPendingMoves; 230 mStaggeredGrid = staggeredGrid; 231 setTargetPosition(TARGET_UNDEFINED); 232 } 233 234 void increasePendingMoves() { 235 if (mPendingMoves < MAX_PENDING_MOVES) { 236 mPendingMoves++; 237 if (mPendingMoves == 0) { 238 dispatchChildSelected(); 239 } 240 } 241 } 242 243 void decreasePendingMoves() { 244 if (mPendingMoves > -MAX_PENDING_MOVES) { 245 mPendingMoves--; 246 if (mPendingMoves == 0) { 247 dispatchChildSelected(); 248 } 249 } 250 } 251 252 /** 253 * Called before laid out an item when non-staggered grid can handle pending movements 254 * by skipping "mNumRows" per movement; staggered grid will have to wait the item 255 * has been laid out in consumePendingMovesAfterLayout(). 256 */ 257 void consumePendingMovesBeforeLayout() { 258 if (mStaggeredGrid || mPendingMoves == 0) { 259 return; 260 } 261 View newSelected = null; 262 int startPos = mPendingMoves > 0 ? mFocusPosition + mNumRows : 263 mFocusPosition - mNumRows; 264 for (int pos = startPos; mPendingMoves != 0; 265 pos = mPendingMoves > 0 ? pos + mNumRows: pos - mNumRows) { 266 View v = findViewByPosition(pos); 267 if (v == null) { 268 break; 269 } 270 if (!canScrollTo(v)) { 271 continue; 272 } 273 newSelected = v; 274 mFocusPosition = pos; 275 if (mPendingMoves > 0) { 276 mPendingMoves--; 277 } else { 278 mPendingMoves++; 279 } 280 } 281 if (newSelected != null && hasFocus()) { 282 mInSelection = true; 283 newSelected.requestFocus(); 284 mInSelection = false; 285 } 286 } 287 288 /** 289 * Called after laid out an item. Staggered grid should find view on same 290 * Row and consume pending movements. 291 */ 292 void consumePendingMovesAfterLayout() { 293 if (mStaggeredGrid && mPendingMoves != 0) { 294 // consume pending moves, focus to item on the same row. 295 final int focusedRow = mGrid != null && mFocusPosition != NO_POSITION ? 296 mGrid.getLocation(mFocusPosition).row : NO_POSITION; 297 View newSelected = null; 298 for (int i = 0, count = getChildCount(); i < count && mPendingMoves != 0; i++) { 299 int index = mPendingMoves > 0 ? i : count - 1 - i; 300 final View child = getChildAt(index); 301 if (!canScrollTo(child)) { 302 continue; 303 } 304 int position = getPositionByIndex(index); 305 Grid.Location loc = mGrid.getLocation(position); 306 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 307 if (mFocusPosition == NO_POSITION) { 308 mFocusPosition = position; 309 newSelected = child; 310 } else if ((mPendingMoves > 0 && position > mFocusPosition) 311 || (mPendingMoves < 0 && position < mFocusPosition)) { 312 mFocusPosition = position; 313 if (mPendingMoves > 0) { 314 mPendingMoves--; 315 } else { 316 mPendingMoves++; 317 } 318 newSelected = child; 319 } 320 } 321 } 322 if (newSelected != null && hasFocus()) { 323 mInSelection = true; 324 newSelected.requestFocus(); 325 mInSelection = false; 326 } 327 if (mPendingMoves == 0) { 328 dispatchChildSelected(); 329 } 330 } 331 if (mPendingMoves == 0 || (mPendingMoves > 0 && hasCreatedLastItem()) 332 || (mPendingMoves < 0 && hasCreatedFirstItem())) { 333 setTargetPosition(mFocusPosition); 334 stop(); 335 } 336 } 337 338 @Override 339 protected void updateActionForInterimTarget(Action action) { 340 if (mPendingMoves == 0) { 341 return; 342 } 343 super.updateActionForInterimTarget(action); 344 } 345 346 @Override 347 public PointF computeScrollVectorForPosition(int targetPosition) { 348 if (mPendingMoves == 0) { 349 return null; 350 } 351 int direction = (mReverseFlowPrimary ? mPendingMoves > 0 : mPendingMoves < 0) ? 352 -1 : 1; 353 if (mOrientation == HORIZONTAL) { 354 return new PointF(direction, 0); 355 } else { 356 return new PointF(0, direction); 357 } 358 } 359 360 @Override 361 boolean needsDispatchChildSelectedOnStop() { 362 return mPendingMoves != 0; 363 } 364 365 @Override 366 protected void onStop() { 367 super.onStop(); 368 // if we hit wall, need clear the remaining pending moves. 369 mPendingMoves = 0; 370 mPendingMoveSmoothScroller = null; 371 View v = findViewByPosition(getTargetPosition()); 372 if (v != null) scrollToView(v, true); 373 } 374 }; 375 376 private static final String TAG = "GridLayoutManager"; 377 private static final boolean DEBUG = false; 378 private static final boolean TRACE = false; 379 380 // maximum pending movement in one direction. 381 private final static int MAX_PENDING_MOVES = 10; 382 383 private String getTag() { 384 return TAG + ":" + mBaseGridView.getId(); 385 } 386 387 private final BaseGridView mBaseGridView; 388 389 /** 390 * Note on conventions in the presence of RTL layout directions: 391 * Many properties and method names reference entities related to the 392 * beginnings and ends of things. In the presence of RTL flows, 393 * it may not be clear whether this is intended to reference a 394 * quantity that changes direction in RTL cases, or a quantity that 395 * does not. Here are the conventions in use: 396 * 397 * start/end: coordinate quantities - do reverse 398 * (optical) left/right: coordinate quantities - do not reverse 399 * low/high: coordinate quantities - do not reverse 400 * min/max: coordinate quantities - do not reverse 401 * scroll offset - coordinate quantities - do not reverse 402 * first/last: positional indices - do not reverse 403 * front/end: positional indices - do not reverse 404 * prepend/append: related to positional indices - do not reverse 405 * 406 * Note that although quantities do not reverse in RTL flows, their 407 * relationship does. In LTR flows, the first positional index is 408 * leftmost; in RTL flows, it is rightmost. Thus, anywhere that 409 * positional quantities are mapped onto coordinate quantities, 410 * the flow must be checked and the logic reversed. 411 */ 412 413 /** 414 * The orientation of a "row". 415 */ 416 private int mOrientation = HORIZONTAL; 417 418 private RecyclerView.State mState; 419 private RecyclerView.Recycler mRecycler; 420 421 private boolean mInLayout; 422 private boolean mInScroll; 423 private boolean mInFastRelayout; 424 /** 425 * During full layout pass, when GridView had focus: onLayoutChildren will 426 * skip non-focusable child and adjust mFocusPosition. 427 */ 428 private boolean mInLayoutSearchFocus; 429 private boolean mInSelection = false; 430 431 private OnChildSelectedListener mChildSelectedListener = 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 * LinearSmoothScroller that consume pending DPAD movements. 444 */ 445 private PendingMoveSmoothScroller mPendingMoveSmoothScroller; 446 447 /** 448 * The offset to be applied to mFocusPosition, due to adapter change, on the next 449 * layout. Set to Integer.MIN_VALUE means item was removed. 450 * TODO: This is somewhat duplication of RecyclerView getOldPosition() which is 451 * unfortunately cleared after prelayout. 452 */ 453 private int mFocusPositionOffset = 0; 454 455 /** 456 * Extra pixels applied on primary direction. 457 */ 458 private int mPrimaryScrollExtra; 459 460 /** 461 * Force a full layout under certain situations. E.g. Rows change, jump to invisible child. 462 */ 463 private boolean mForceFullLayout; 464 465 /** 466 * True if layout is enabled. 467 */ 468 private boolean mLayoutEnabled = true; 469 470 /** 471 * override child visibility 472 */ 473 private int mChildVisibility = -1; 474 475 /** 476 * The scroll offsets of the viewport relative to the entire view. 477 */ 478 private int mScrollOffsetPrimary; 479 private int mScrollOffsetSecondary; 480 481 /** 482 * User-specified row height/column width. Can be WRAP_CONTENT. 483 */ 484 private int mRowSizeSecondaryRequested; 485 486 /** 487 * The fixed size of each grid item in the secondary direction. This corresponds to 488 * the row height, equal for all rows. Grid items may have variable length 489 * in the primary direction. 490 */ 491 private int mFixedRowSizeSecondary; 492 493 /** 494 * Tracks the secondary size of each row. 495 */ 496 private int[] mRowSizeSecondary; 497 498 /** 499 * Flag controlling whether the current/next layout should 500 * be updating the secondary size of rows. 501 */ 502 private boolean mRowSecondarySizeRefresh; 503 504 /** 505 * The maximum measured size of the view. 506 */ 507 private int mMaxSizeSecondary; 508 509 /** 510 * Margin between items. 511 */ 512 private int mHorizontalMargin; 513 /** 514 * Margin between items vertically. 515 */ 516 private int mVerticalMargin; 517 /** 518 * Margin in main direction. 519 */ 520 private int mMarginPrimary; 521 /** 522 * Margin in second direction. 523 */ 524 private int mMarginSecondary; 525 /** 526 * How to position child in secondary direction. 527 */ 528 private int mGravity = Gravity.START | Gravity.TOP; 529 /** 530 * The number of rows in the grid. 531 */ 532 private int mNumRows; 533 /** 534 * Number of rows requested, can be 0 to be determined by parent size and 535 * rowHeight. 536 */ 537 private int mNumRowsRequested = 1; 538 539 /** 540 * Saves grid information of each view. 541 */ 542 Grid mGrid; 543 544 /** 545 * Focus Scroll strategy. 546 */ 547 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 548 /** 549 * Defines how item view is aligned in the window. 550 */ 551 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 552 553 /** 554 * Defines how item view is aligned. 555 */ 556 private final ItemAlignment mItemAlignment = new ItemAlignment(); 557 558 /** 559 * Dimensions of the view, width or height depending on orientation. 560 */ 561 private int mSizePrimary; 562 563 /** 564 * Allow DPAD key to navigate out at the front of the View (where position = 0), 565 * default is false. 566 */ 567 private boolean mFocusOutFront; 568 569 /** 570 * Allow DPAD key to navigate out at the end of the view, default is false. 571 */ 572 private boolean mFocusOutEnd; 573 574 /** 575 * True if focus search is disabled. 576 */ 577 private boolean mFocusSearchDisabled; 578 579 /** 580 * True if prune child, might be disabled during transition. 581 */ 582 private boolean mPruneChild = true; 583 584 /** 585 * True if scroll content, might be disabled during transition. 586 */ 587 private boolean mScrollEnabled = true; 588 589 /** 590 * Temporary variable: an int array of length=2. 591 */ 592 private static int[] sTwoInts = new int[2]; 593 594 /** 595 * Set to true for RTL layout in horizontal orientation 596 */ 597 private boolean mReverseFlowPrimary = false; 598 599 /** 600 * Set to true for RTL layout in vertical orientation 601 */ 602 private boolean mReverseFlowSecondary = false; 603 604 /** 605 * Temporaries used for measuring. 606 */ 607 private int[] mMeasuredDimension = new int[2]; 608 609 final ViewsStateBundle mChildrenStates = new ViewsStateBundle(); 610 611 public GridLayoutManager(BaseGridView baseGridView) { 612 mBaseGridView = baseGridView; 613 } 614 615 public void setOrientation(int orientation) { 616 if (orientation != HORIZONTAL && orientation != VERTICAL) { 617 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 618 return; 619 } 620 621 mOrientation = orientation; 622 mWindowAlignment.setOrientation(orientation); 623 mItemAlignment.setOrientation(orientation); 624 mForceFullLayout = true; 625 } 626 627 public void onRtlPropertiesChanged(int layoutDirection) { 628 if (mOrientation == HORIZONTAL) { 629 mReverseFlowPrimary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 630 mReverseFlowSecondary = false; 631 } else { 632 mReverseFlowSecondary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 633 mReverseFlowPrimary = false; 634 } 635 mWindowAlignment.horizontal.setReversedFlow(layoutDirection == View.LAYOUT_DIRECTION_RTL); 636 } 637 638 public int getFocusScrollStrategy() { 639 return mFocusScrollStrategy; 640 } 641 642 public void setFocusScrollStrategy(int focusScrollStrategy) { 643 mFocusScrollStrategy = focusScrollStrategy; 644 } 645 646 public void setWindowAlignment(int windowAlignment) { 647 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 648 } 649 650 public int getWindowAlignment() { 651 return mWindowAlignment.mainAxis().getWindowAlignment(); 652 } 653 654 public void setWindowAlignmentOffset(int alignmentOffset) { 655 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 656 } 657 658 public int getWindowAlignmentOffset() { 659 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 660 } 661 662 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 663 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 664 } 665 666 public float getWindowAlignmentOffsetPercent() { 667 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 668 } 669 670 public void setItemAlignmentOffset(int alignmentOffset) { 671 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 672 updateChildAlignments(); 673 } 674 675 public int getItemAlignmentOffset() { 676 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 677 } 678 679 public void setItemAlignmentOffsetWithPadding(boolean withPadding) { 680 mItemAlignment.mainAxis().setItemAlignmentOffsetWithPadding(withPadding); 681 updateChildAlignments(); 682 } 683 684 public boolean isItemAlignmentOffsetWithPadding() { 685 return mItemAlignment.mainAxis().isItemAlignmentOffsetWithPadding(); 686 } 687 688 public void setItemAlignmentOffsetPercent(float offsetPercent) { 689 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 690 updateChildAlignments(); 691 } 692 693 public float getItemAlignmentOffsetPercent() { 694 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 695 } 696 697 public void setItemAlignmentViewId(int viewId) { 698 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 699 updateChildAlignments(); 700 } 701 702 public int getItemAlignmentViewId() { 703 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 704 } 705 706 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 707 mFocusOutFront = throughFront; 708 mFocusOutEnd = throughEnd; 709 } 710 711 public void setNumRows(int numRows) { 712 if (numRows < 0) throw new IllegalArgumentException(); 713 mNumRowsRequested = numRows; 714 mForceFullLayout = true; 715 } 716 717 /** 718 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 719 */ 720 public void setRowHeight(int height) { 721 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 722 mRowSizeSecondaryRequested = height; 723 } else { 724 throw new IllegalArgumentException("Invalid row height: " + height); 725 } 726 } 727 728 public void setItemMargin(int margin) { 729 mVerticalMargin = mHorizontalMargin = margin; 730 mMarginPrimary = mMarginSecondary = margin; 731 } 732 733 public void setVerticalMargin(int margin) { 734 if (mOrientation == HORIZONTAL) { 735 mMarginSecondary = mVerticalMargin = margin; 736 } else { 737 mMarginPrimary = mVerticalMargin = margin; 738 } 739 } 740 741 public void setHorizontalMargin(int margin) { 742 if (mOrientation == HORIZONTAL) { 743 mMarginPrimary = mHorizontalMargin = margin; 744 } else { 745 mMarginSecondary = mHorizontalMargin = margin; 746 } 747 } 748 749 public int getVerticalMargin() { 750 return mVerticalMargin; 751 } 752 753 public int getHorizontalMargin() { 754 return mHorizontalMargin; 755 } 756 757 public void setGravity(int gravity) { 758 mGravity = gravity; 759 } 760 761 protected boolean hasDoneFirstLayout() { 762 return mGrid != null; 763 } 764 765 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 766 mChildSelectedListener = listener; 767 } 768 769 void setOnChildLaidOutListener(OnChildLaidOutListener listener) { 770 mChildLaidOutListener = listener; 771 } 772 773 private int getPositionByView(View view) { 774 if (view == null) { 775 return NO_POSITION; 776 } 777 LayoutParams params = (LayoutParams) view.getLayoutParams(); 778 if (params == null || params.isItemRemoved()) { 779 // when item is removed, the position value can be any value. 780 return NO_POSITION; 781 } 782 return params.getViewPosition(); 783 } 784 785 private int getPositionByIndex(int index) { 786 return getPositionByView(getChildAt(index)); 787 } 788 789 private void dispatchChildSelected() { 790 if (mChildSelectedListener == null) { 791 return; 792 } 793 794 if (TRACE) TraceHelper.beginSection("onChildSelected"); 795 View view = mFocusPosition == NO_POSITION ? null : findViewByPosition(mFocusPosition); 796 if (view != null) { 797 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(view); 798 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 799 vh == null? NO_ID: vh.getItemId()); 800 } else { 801 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 802 } 803 if (TRACE) TraceHelper.endSection(); 804 805 // Children may request layout when a child selection event occurs (such as a change of 806 // padding on the current and previously selected rows). 807 // If in layout, a child requesting layout may have been laid out before the selection 808 // callback. 809 // If it was not, the child will be laid out after the selection callback. 810 // If so, the layout request will be honoured though the view system will emit a double- 811 // layout warning. 812 // If not in layout, we may be scrolling in which case the child layout request will be 813 // eaten by recyclerview. Post a requestLayout. 814 if (!mInLayout && !mBaseGridView.isLayoutRequested()) { 815 int childCount = getChildCount(); 816 for (int i = 0; i < childCount; i++) { 817 if (getChildAt(i).isLayoutRequested()) { 818 forceRequestLayout(); 819 break; 820 } 821 } 822 } 823 } 824 825 @Override 826 public boolean canScrollHorizontally() { 827 // We can scroll horizontally if we have horizontal orientation, or if 828 // we are vertical and have more than one column. 829 return mOrientation == HORIZONTAL || mNumRows > 1; 830 } 831 832 @Override 833 public boolean canScrollVertically() { 834 // We can scroll vertically if we have vertical orientation, or if we 835 // are horizontal and have more than one row. 836 return mOrientation == VERTICAL || mNumRows > 1; 837 } 838 839 @Override 840 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 841 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 842 ViewGroup.LayoutParams.WRAP_CONTENT); 843 } 844 845 @Override 846 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 847 return new LayoutParams(context, attrs); 848 } 849 850 @Override 851 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 852 if (lp instanceof LayoutParams) { 853 return new LayoutParams((LayoutParams) lp); 854 } else if (lp instanceof RecyclerView.LayoutParams) { 855 return new LayoutParams((RecyclerView.LayoutParams) lp); 856 } else if (lp instanceof MarginLayoutParams) { 857 return new LayoutParams((MarginLayoutParams) lp); 858 } else { 859 return new LayoutParams(lp); 860 } 861 } 862 863 protected View getViewForPosition(int position) { 864 return mRecycler.getViewForPosition(position); 865 } 866 867 final int getOpticalLeft(View v) { 868 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 869 } 870 871 final int getOpticalRight(View v) { 872 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 873 } 874 875 final int getOpticalTop(View v) { 876 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 877 } 878 879 final int getOpticalBottom(View v) { 880 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 881 } 882 883 private int getViewMin(View v) { 884 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 885 } 886 887 private int getViewMax(View v) { 888 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 889 } 890 891 private int getViewCenter(View view) { 892 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 893 } 894 895 private int getViewCenterSecondary(View view) { 896 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 897 } 898 899 private int getViewCenterX(View v) { 900 LayoutParams p = (LayoutParams) v.getLayoutParams(); 901 return p.getOpticalLeft(v) + p.getAlignX(); 902 } 903 904 private int getViewCenterY(View v) { 905 LayoutParams p = (LayoutParams) v.getLayoutParams(); 906 return p.getOpticalTop(v) + p.getAlignY(); 907 } 908 909 /** 910 * Save Recycler and State for convenience. Must be paired with leaveContext(). 911 */ 912 private void saveContext(Recycler recycler, State state) { 913 if (mRecycler != null || mState != null) { 914 Log.e(TAG, "Recycler information was not released, bug!"); 915 } 916 mRecycler = recycler; 917 mState = state; 918 } 919 920 /** 921 * Discard saved Recycler and State. 922 */ 923 private void leaveContext() { 924 mRecycler = null; 925 mState = null; 926 } 927 928 /** 929 * Re-initialize data structures for a data change or handling invisible 930 * selection. The method tries its best to preserve position information so 931 * that staggered grid looks same before and after re-initialize. 932 * @return true if can fastRelayout() 933 */ 934 private boolean layoutInit() { 935 boolean focusViewWasInTree = mGrid != null && mFocusPosition >= 0 936 && mFocusPosition >= mGrid.getFirstVisibleIndex() 937 && mFocusPosition <= mGrid.getLastVisibleIndex(); 938 final int newItemCount = mState.getItemCount(); 939 if (newItemCount == 0) { 940 mFocusPosition = NO_POSITION; 941 } else if (mFocusPosition >= newItemCount) { 942 mFocusPosition = newItemCount - 1; 943 } else if (mFocusPosition == NO_POSITION && newItemCount > 0) { 944 // if focus position is never set before, initialize it to 0 945 mFocusPosition = 0; 946 } 947 if (!mState.didStructureChange() && mGrid.getFirstVisibleIndex() >= 0 && 948 !mForceFullLayout && mGrid != null) { 949 updateScrollController(); 950 updateScrollSecondAxis(); 951 mGrid.setMargin(mMarginPrimary); 952 if (!focusViewWasInTree && mFocusPosition != NO_POSITION) { 953 mGrid.setStart(mFocusPosition); 954 } 955 return true; 956 } else { 957 mForceFullLayout = false; 958 int firstVisibleIndex = focusViewWasInTree ? mGrid.getFirstVisibleIndex() : 0; 959 960 if (mGrid == null || mNumRows != mGrid.getNumRows() || 961 mReverseFlowPrimary != mGrid.isReversedFlow()) { 962 mGrid = Grid.createStaggeredMultipleRows(mNumRows); 963 mGrid.setProvider(mGridProvider); 964 mGrid.setReversedFlow(mReverseFlowPrimary); 965 } 966 initScrollController(); 967 updateScrollSecondAxis(); 968 mGrid.setMargin(mMarginPrimary); 969 detachAndScrapAttachedViews(mRecycler); 970 mGrid.resetVisibleIndex(); 971 if (mFocusPosition == NO_POSITION) { 972 mBaseGridView.clearFocus(); 973 } 974 mWindowAlignment.mainAxis().invalidateScrollMin(); 975 mWindowAlignment.mainAxis().invalidateScrollMax(); 976 if (focusViewWasInTree && firstVisibleIndex <= mFocusPosition) { 977 // if focusView was in tree, we will add item from first visible item 978 mGrid.setStart(firstVisibleIndex); 979 } else { 980 // if focusView was not in tree, it's probably because focus position jumped 981 // far away from visible range, so use mFocusPosition as start 982 mGrid.setStart(mFocusPosition); 983 } 984 return false; 985 } 986 } 987 988 private int getRowSizeSecondary(int rowIndex) { 989 if (mFixedRowSizeSecondary != 0) { 990 return mFixedRowSizeSecondary; 991 } 992 if (mRowSizeSecondary == null) { 993 return 0; 994 } 995 return mRowSizeSecondary[rowIndex]; 996 } 997 998 private int getRowStartSecondary(int rowIndex) { 999 int start = 0; 1000 // Iterate from left to right, which is a different index traversal 1001 // in RTL flow 1002 if (mReverseFlowSecondary) { 1003 for (int i = mNumRows-1; i > rowIndex; i--) { 1004 start += getRowSizeSecondary(i) + mMarginSecondary; 1005 } 1006 } else { 1007 for (int i = 0; i < rowIndex; i++) { 1008 start += getRowSizeSecondary(i) + mMarginSecondary; 1009 } 1010 } 1011 return start; 1012 } 1013 1014 private int getSizeSecondary() { 1015 int rightmostIndex = mReverseFlowSecondary ? 0 : mNumRows - 1; 1016 return getRowStartSecondary(rightmostIndex) + getRowSizeSecondary(rightmostIndex); 1017 } 1018 1019 private void measureScrapChild(int position, int widthSpec, int heightSpec, 1020 int[] measuredDimension) { 1021 View view = mRecycler.getViewForPosition(position); 1022 if (view != null) { 1023 LayoutParams p = (LayoutParams) view.getLayoutParams(); 1024 int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, 1025 getPaddingLeft() + getPaddingRight(), p.width); 1026 int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, 1027 getPaddingTop() + getPaddingBottom(), p.height); 1028 view.measure(childWidthSpec, childHeightSpec); 1029 measuredDimension[0] = view.getMeasuredWidth(); 1030 measuredDimension[1] = view.getMeasuredHeight(); 1031 mRecycler.recycleView(view); 1032 } 1033 } 1034 1035 private boolean processRowSizeSecondary(boolean measure) { 1036 if (mFixedRowSizeSecondary != 0) { 1037 return false; 1038 } 1039 1040 if (TRACE) TraceHelper.beginSection("processRowSizeSecondary"); 1041 CircularIntArray[] rows = mGrid == null ? null : mGrid.getItemPositionsInRows(); 1042 boolean changed = false; 1043 int scrapChildWidth = -1; 1044 int scrapChildHeight = -1; 1045 1046 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 1047 CircularIntArray row = rows == null ? null : rows[rowIndex]; 1048 final int rowItemsPairCount = row == null ? 0 : row.size(); 1049 int rowSize = -1; 1050 for (int rowItemPairIndex = 0; rowItemPairIndex < rowItemsPairCount; 1051 rowItemPairIndex += 2) { 1052 final int rowIndexStart = row.get(rowItemPairIndex); 1053 final int rowIndexEnd = row.get(rowItemPairIndex + 1); 1054 for (int i = rowIndexStart; i <= rowIndexEnd; i++) { 1055 final View view = findViewByPosition(i); 1056 if (view == null) { 1057 continue; 1058 } 1059 if (measure && view.isLayoutRequested()) { 1060 measureChild(view); 1061 } 1062 final int secondarySize = mOrientation == HORIZONTAL ? 1063 view.getMeasuredHeight() : view.getMeasuredWidth(); 1064 if (secondarySize > rowSize) { 1065 rowSize = secondarySize; 1066 } 1067 } 1068 } 1069 1070 final int itemCount = mState.getItemCount(); 1071 if (measure && rowSize < 0 && itemCount > 0) { 1072 if (scrapChildWidth < 0 && scrapChildHeight < 0) { 1073 int position; 1074 if (mFocusPosition == NO_POSITION) { 1075 position = 0; 1076 } else if (mFocusPosition >= itemCount) { 1077 position = itemCount - 1; 1078 } else { 1079 position = mFocusPosition; 1080 } 1081 measureScrapChild(position, 1082 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1083 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1084 mMeasuredDimension); 1085 scrapChildWidth = mMeasuredDimension[0]; 1086 scrapChildHeight = mMeasuredDimension[1]; 1087 if (DEBUG) Log.v(TAG, "measured scrap child: " + scrapChildWidth + 1088 " " + scrapChildHeight); 1089 } 1090 rowSize = mOrientation == HORIZONTAL ? scrapChildHeight : scrapChildWidth; 1091 } 1092 if (rowSize < 0) { 1093 rowSize = 0; 1094 } 1095 if (mRowSizeSecondary[rowIndex] != rowSize) { 1096 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 1097 ", " + rowSize); 1098 mRowSizeSecondary[rowIndex] = rowSize; 1099 changed = true; 1100 } 1101 } 1102 1103 if (TRACE) TraceHelper.endSection(); 1104 return changed; 1105 } 1106 1107 /** 1108 * Checks if we need to update row secondary sizes. 1109 */ 1110 private void updateRowSecondarySizeRefresh() { 1111 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 1112 if (mRowSecondarySizeRefresh) { 1113 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 1114 forceRequestLayout(); 1115 } 1116 } 1117 1118 private void forceRequestLayout() { 1119 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 1120 // RecyclerView prevents us from requesting layout in many cases 1121 // (during layout, during scroll, etc.) 1122 // For secondary row size wrap_content support we currently need a 1123 // second layout pass to update the measured size after having measured 1124 // and added child views in layoutChildren. 1125 // Force the second layout by posting a delayed runnable. 1126 // TODO: investigate allowing a second layout pass, 1127 // or move child add/measure logic to the measure phase. 1128 ViewCompat.postOnAnimation(mBaseGridView, mRequestLayoutRunnable); 1129 } 1130 1131 private final Runnable mRequestLayoutRunnable = new Runnable() { 1132 @Override 1133 public void run() { 1134 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 1135 requestLayout(); 1136 } 1137 }; 1138 1139 @Override 1140 public void onMeasure(Recycler recycler, State state, int widthSpec, int heightSpec) { 1141 saveContext(recycler, state); 1142 1143 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 1144 int measuredSizeSecondary; 1145 if (mOrientation == HORIZONTAL) { 1146 sizePrimary = MeasureSpec.getSize(widthSpec); 1147 sizeSecondary = MeasureSpec.getSize(heightSpec); 1148 modeSecondary = MeasureSpec.getMode(heightSpec); 1149 paddingSecondary = getPaddingTop() + getPaddingBottom(); 1150 } else { 1151 sizeSecondary = MeasureSpec.getSize(widthSpec); 1152 sizePrimary = MeasureSpec.getSize(heightSpec); 1153 modeSecondary = MeasureSpec.getMode(widthSpec); 1154 paddingSecondary = getPaddingLeft() + getPaddingRight(); 1155 } 1156 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 1157 " heightSpec " + Integer.toHexString(heightSpec) + 1158 " modeSecondary " + Integer.toHexString(modeSecondary) + 1159 " sizeSecondary " + sizeSecondary + " " + this); 1160 1161 mMaxSizeSecondary = sizeSecondary; 1162 1163 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 1164 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1165 mFixedRowSizeSecondary = 0; 1166 1167 if (mRowSizeSecondary == null || mRowSizeSecondary.length != mNumRows) { 1168 mRowSizeSecondary = new int[mNumRows]; 1169 } 1170 1171 // Measure all current children and update cached row heights 1172 processRowSizeSecondary(true); 1173 1174 switch (modeSecondary) { 1175 case MeasureSpec.UNSPECIFIED: 1176 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 1177 break; 1178 case MeasureSpec.AT_MOST: 1179 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 1180 mMaxSizeSecondary); 1181 break; 1182 case MeasureSpec.EXACTLY: 1183 measuredSizeSecondary = mMaxSizeSecondary; 1184 break; 1185 default: 1186 throw new IllegalStateException("wrong spec"); 1187 } 1188 1189 } else { 1190 switch (modeSecondary) { 1191 case MeasureSpec.UNSPECIFIED: 1192 if (mRowSizeSecondaryRequested == 0) { 1193 if (mOrientation == HORIZONTAL) { 1194 throw new IllegalStateException("Must specify rowHeight or view height"); 1195 } else { 1196 throw new IllegalStateException("Must specify columnWidth or view width"); 1197 } 1198 } 1199 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1200 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1201 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1202 * (mNumRows - 1) + paddingSecondary; 1203 break; 1204 case MeasureSpec.AT_MOST: 1205 case MeasureSpec.EXACTLY: 1206 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 1207 mNumRows = 1; 1208 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 1209 } else if (mNumRowsRequested == 0) { 1210 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1211 mNumRows = (sizeSecondary + mMarginSecondary) 1212 / (mRowSizeSecondaryRequested + mMarginSecondary); 1213 } else if (mRowSizeSecondaryRequested == 0) { 1214 mNumRows = mNumRowsRequested; 1215 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 1216 * (mNumRows - 1)) / mNumRows; 1217 } else { 1218 mNumRows = mNumRowsRequested; 1219 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1220 } 1221 measuredSizeSecondary = sizeSecondary; 1222 if (modeSecondary == MeasureSpec.AT_MOST) { 1223 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1224 * (mNumRows - 1) + paddingSecondary; 1225 if (childrenSize < measuredSizeSecondary) { 1226 measuredSizeSecondary = childrenSize; 1227 } 1228 } 1229 break; 1230 default: 1231 throw new IllegalStateException("wrong spec"); 1232 } 1233 } 1234 if (mOrientation == HORIZONTAL) { 1235 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1236 } else { 1237 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1238 } 1239 if (DEBUG) { 1240 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1241 " measuredSizeSecondary " + measuredSizeSecondary + 1242 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1243 " mNumRows " + mNumRows); 1244 } 1245 leaveContext(); 1246 } 1247 1248 private void measureChild(View child) { 1249 if (TRACE) TraceHelper.beginSection("measureChild"); 1250 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1251 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1252 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1253 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1254 int widthSpec, heightSpec; 1255 1256 if (mOrientation == HORIZONTAL) { 1257 widthSpec = ViewGroup.getChildMeasureSpec( 1258 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1259 0, lp.width); 1260 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1261 } else { 1262 heightSpec = ViewGroup.getChildMeasureSpec( 1263 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1264 0, lp.height); 1265 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1266 } 1267 child.measure(widthSpec, heightSpec); 1268 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1269 " widthSpec " + Integer.toHexString(widthSpec) + 1270 " heightSpec " + Integer.toHexString(heightSpec) + 1271 " measuredWidth " + child.getMeasuredWidth() + 1272 " measuredHeight " + child.getMeasuredHeight()); 1273 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1274 if (TRACE) TraceHelper.endSection(); 1275 } 1276 1277 private Grid.Provider mGridProvider = new Grid.Provider() { 1278 1279 @Override 1280 public int getCount() { 1281 return mState.getItemCount(); 1282 } 1283 1284 @Override 1285 public int createItem(int index, boolean append, Object[] item) { 1286 if (TRACE) TraceHelper.beginSection("createItem"); 1287 if (TRACE) TraceHelper.beginSection("getview"); 1288 View v = getViewForPosition(index); 1289 if (TRACE) TraceHelper.endSection(); 1290 // See recyclerView docs: we don't need re-add scraped view if it was removed. 1291 if (!((RecyclerView.LayoutParams) v.getLayoutParams()).isItemRemoved()) { 1292 if (TRACE) TraceHelper.beginSection("addView"); 1293 if (append) { 1294 addView(v); 1295 } else { 1296 addView(v, 0); 1297 } 1298 if (TRACE) TraceHelper.endSection(); 1299 if (mChildVisibility != -1) { 1300 v.setVisibility(mChildVisibility); 1301 } 1302 1303 if (mPendingMoveSmoothScroller != null) { 1304 mPendingMoveSmoothScroller.consumePendingMovesBeforeLayout(); 1305 } 1306 if (!mInLayout) { 1307 // when we are appending item during scroll pass and the item's position 1308 // matches the mFocusPosition, we should signal a childSelected event. 1309 // However if we are still running PendingMoveSmoothScroller, we defer and 1310 // signal the event in PendingMoveSmoothScroller.onStop(). This can 1311 // avoid lots of childSelected events during a long smooth scrolling and 1312 // increase performance. 1313 if (index == mFocusPosition && (mPendingMoveSmoothScroller == null 1314 || mPendingMoveSmoothScroller.mPendingMoves == 0)) { 1315 dispatchChildSelected(); 1316 } 1317 } else if (!mInFastRelayout) { 1318 // fastRelayout will dispatch event at end of onLayoutChildren(). 1319 // For full layout, two situations here: 1320 // 1. mInLayoutSearchFocus is false, dispatchChildSelected() at mFocusPosition. 1321 // 2. mInLayoutSearchFocus is true: dispatchChildSelected() on first child 1322 // equal to or after mFocusPosition that can take focus. 1323 if (!mInLayoutSearchFocus && index == mFocusPosition) { 1324 dispatchChildSelected(); 1325 } else if (mInLayoutSearchFocus && index >= mFocusPosition 1326 && v.hasFocusable()) { 1327 mFocusPosition = index; 1328 mInLayoutSearchFocus = false; 1329 dispatchChildSelected(); 1330 } 1331 } 1332 measureChild(v); 1333 } 1334 item[0] = v; 1335 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1336 } 1337 1338 @Override 1339 public void addItem(Object item, int index, int length, int rowIndex, int edge) { 1340 View v = (View) item; 1341 int start, end; 1342 if (edge == Integer.MIN_VALUE || edge == Integer.MAX_VALUE) { 1343 edge = !mGrid.isReversedFlow() ? mWindowAlignment.mainAxis().getPaddingLow() 1344 : mWindowAlignment.mainAxis().getSize() 1345 - mWindowAlignment.mainAxis().getPaddingHigh(); 1346 } 1347 boolean edgeIsMin = !mGrid.isReversedFlow(); 1348 if (edgeIsMin) { 1349 start = edge; 1350 end = edge + length; 1351 } else { 1352 start = edge - length; 1353 end = edge; 1354 } 1355 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1356 mChildrenStates.loadView(v, index); 1357 layoutChild(rowIndex, v, start, end, startSecondary); 1358 if (DEBUG) { 1359 Log.d(getTag(), "addView " + index + " " + v); 1360 } 1361 if (TRACE) TraceHelper.endSection(); 1362 1363 if (index == mGrid.getFirstVisibleIndex()) { 1364 if (!mGrid.isReversedFlow()) { 1365 updateScrollMin(); 1366 } else { 1367 updateScrollMax(); 1368 } 1369 } 1370 if (index == mGrid.getLastVisibleIndex()) { 1371 if (!mGrid.isReversedFlow()) { 1372 updateScrollMax(); 1373 } else { 1374 updateScrollMin(); 1375 } 1376 } 1377 if (!mInLayout && mPendingMoveSmoothScroller != null) { 1378 mPendingMoveSmoothScroller.consumePendingMovesAfterLayout(); 1379 } 1380 if (mChildLaidOutListener != null) { 1381 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(v); 1382 mChildLaidOutListener.onChildLaidOut(mBaseGridView, v, index, 1383 vh == null ? NO_ID : vh.getItemId()); 1384 } 1385 } 1386 1387 @Override 1388 public void removeItem(int index) { 1389 if (TRACE) TraceHelper.beginSection("removeItem"); 1390 View v = findViewByPosition(index); 1391 if (mInLayout) { 1392 detachAndScrapView(v, mRecycler); 1393 } else { 1394 removeAndRecycleView(v, mRecycler); 1395 } 1396 if (TRACE) TraceHelper.endSection(); 1397 } 1398 1399 @Override 1400 public int getEdge(int index) { 1401 if (mReverseFlowPrimary) { 1402 return getViewMax(findViewByPosition(index)); 1403 } else { 1404 return getViewMin(findViewByPosition(index)); 1405 } 1406 } 1407 1408 @Override 1409 public int getSize(int index) { 1410 final View v = findViewByPosition(index); 1411 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1412 } 1413 }; 1414 1415 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1416 if (TRACE) TraceHelper.beginSection("layoutChild"); 1417 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1418 : v.getMeasuredWidth(); 1419 if (mFixedRowSizeSecondary > 0) { 1420 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1421 } 1422 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1423 final int horizontalGravity = (mReverseFlowPrimary || mReverseFlowSecondary) ? 1424 Gravity.getAbsoluteGravity(mGravity & Gravity.RELATIVE_HORIZONTAL_GRAVITY_MASK, View.LAYOUT_DIRECTION_RTL) : 1425 mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1426 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1427 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1428 // do nothing 1429 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1430 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1431 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1432 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1433 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1434 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1435 } 1436 int left, top, right, bottom; 1437 if (mOrientation == HORIZONTAL) { 1438 left = start; 1439 top = startSecondary; 1440 right = end; 1441 bottom = startSecondary + sizeSecondary; 1442 } else { 1443 top = start; 1444 left = startSecondary; 1445 bottom = end; 1446 right = startSecondary + sizeSecondary; 1447 } 1448 v.layout(left, top, right, bottom); 1449 updateChildOpticalInsets(v, left, top, right, bottom); 1450 updateChildAlignments(v); 1451 if (TRACE) TraceHelper.endSection(); 1452 } 1453 1454 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1455 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1456 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1457 v.getRight() - right, v.getBottom() - bottom); 1458 } 1459 1460 private void updateChildAlignments(View v) { 1461 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1462 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1463 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1464 } 1465 1466 private void updateChildAlignments() { 1467 for (int i = 0, c = getChildCount(); i < c; i++) { 1468 updateChildAlignments(getChildAt(i)); 1469 } 1470 } 1471 1472 private void removeInvisibleViewsAtEnd() { 1473 if (mPruneChild) { 1474 mGrid.removeInvisibleItemsAtEnd(mFocusPosition, 1475 mReverseFlowPrimary ? 0 : mSizePrimary); 1476 } 1477 } 1478 1479 private void removeInvisibleViewsAtFront() { 1480 if (mPruneChild) { 1481 mGrid.removeInvisibleItemsAtFront(mFocusPosition, 1482 mReverseFlowPrimary ? mSizePrimary : 0); 1483 } 1484 } 1485 1486 private boolean appendOneColumnVisibleItems() { 1487 return mGrid.appendOneColumnVisibleItems(); 1488 } 1489 1490 private boolean prependOneColumnVisibleItems() { 1491 return mGrid.prependOneColumnVisibleItems(); 1492 } 1493 1494 private void appendVisibleItems() { 1495 mGrid.appendVisibleItems(mReverseFlowPrimary ? 0 : mSizePrimary); 1496 } 1497 1498 private void prependVisibleItems() { 1499 mGrid.prependVisibleItems(mReverseFlowPrimary ? mSizePrimary : 0); 1500 } 1501 1502 /** 1503 * Fast layout when there is no structure change, adapter change, etc. 1504 * It will layout all views was layout requested or updated, until hit a view 1505 * with different size, then it break and detachAndScrap all views after that. 1506 */ 1507 private void fastRelayout() { 1508 boolean invalidateAfter = false; 1509 final int childCount = getChildCount(); 1510 int position = -1; 1511 for (int index = 0; index < childCount; index++) { 1512 View view = getChildAt(index); 1513 position = getPositionByIndex(index); 1514 Grid.Location location = mGrid.getLocation(position); 1515 if (location == null) { 1516 if (DEBUG) Log.w(getTag(), "fastRelayout(): no Location at " + position); 1517 invalidateAfter = true; 1518 break; 1519 } 1520 1521 int startSecondary = getRowStartSecondary(location.row) - mScrollOffsetSecondary; 1522 int primarySize, end; 1523 int start = getViewMin(view); 1524 int oldPrimarySize = (mOrientation == HORIZONTAL) ? 1525 view.getMeasuredWidth() : 1526 view.getMeasuredHeight(); 1527 1528 LayoutParams lp = (LayoutParams) view.getLayoutParams(); 1529 if (lp.viewNeedsUpdate()) { 1530 int viewIndex = mBaseGridView.indexOfChild(view); 1531 detachAndScrapView(view, mRecycler); 1532 view = getViewForPosition(position); 1533 addView(view, viewIndex); 1534 } 1535 1536 if (view.isLayoutRequested()) { 1537 measureChild(view); 1538 } 1539 if (mOrientation == HORIZONTAL) { 1540 primarySize = view.getMeasuredWidth(); 1541 end = start + primarySize; 1542 } else { 1543 primarySize = view.getMeasuredHeight(); 1544 end = start + primarySize; 1545 } 1546 layoutChild(location.row, view, start, end, startSecondary); 1547 if (oldPrimarySize != primarySize) { 1548 // size changed invalidate remaining Locations 1549 if (DEBUG) Log.d(getTag(), "fastRelayout: view size changed at " + position); 1550 invalidateAfter = true; 1551 break; 1552 } 1553 } 1554 if (invalidateAfter) { 1555 final int savedLastPos = mGrid.getLastVisibleIndex(); 1556 mGrid.invalidateItemsAfter(position); 1557 if (mPruneChild) { 1558 // in regular prune child mode, we just append items up to edge limit 1559 appendVisibleItems(); 1560 if (mFocusPosition >= 0 && mFocusPosition <= savedLastPos) { 1561 // make sure add focus view back: the view might be outside edge limit 1562 // when there is delta in onLayoutChildren(). 1563 while (mGrid.getLastVisibleIndex() < mFocusPosition) { 1564 mGrid.appendOneColumnVisibleItems(); 1565 } 1566 } 1567 } else { 1568 // prune disabled(e.g. in RowsFragment transition): append all removed items 1569 while (mGrid.appendOneColumnVisibleItems() 1570 && mGrid.getLastVisibleIndex() < savedLastPos); 1571 } 1572 } 1573 updateScrollMin(); 1574 updateScrollMax(); 1575 updateScrollSecondAxis(); 1576 } 1577 1578 public void removeAndRecycleAllViews(RecyclerView.Recycler recycler) { 1579 if (TRACE) TraceHelper.beginSection("removeAndRecycleAllViews"); 1580 if (DEBUG) Log.v(TAG, "removeAndRecycleAllViews " + getChildCount()); 1581 for (int i = getChildCount() - 1; i >= 0; i--) { 1582 removeAndRecycleViewAt(i, recycler); 1583 } 1584 if (TRACE) TraceHelper.endSection(); 1585 } 1586 1587 // Lays out items based on the current scroll position 1588 @Override 1589 public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) { 1590 if (DEBUG) { 1591 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1592 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1593 + " inPreLayout " + state.isPreLayout() 1594 + " didStructureChange " + state.didStructureChange() 1595 + " mForceFullLayout " + mForceFullLayout); 1596 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1597 } 1598 1599 if (mNumRows == 0) { 1600 // haven't done measure yet 1601 return; 1602 } 1603 final int itemCount = state.getItemCount(); 1604 if (itemCount < 0) { 1605 return; 1606 } 1607 1608 if (!mLayoutEnabled) { 1609 discardLayoutInfo(); 1610 removeAndRecycleAllViews(recycler); 1611 return; 1612 } 1613 mInLayout = true; 1614 1615 final boolean scrollToFocus = !isSmoothScrolling() 1616 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED; 1617 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1618 mFocusPosition = mFocusPosition + mFocusPositionOffset; 1619 mFocusPositionOffset = 0; 1620 } 1621 saveContext(recycler, state); 1622 1623 // Track the old focus view so we can adjust our system scroll position 1624 // so that any scroll animations happening now will remain valid. 1625 // We must use same delta in Pre Layout (if prelayout exists) and second layout. 1626 // So we cache the deltas in PreLayout and use it in second layout. 1627 int delta = 0, deltaSecondary = 0; 1628 if (mFocusPosition != NO_POSITION && scrollToFocus 1629 && mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE) { 1630 // FIXME: we should get the remaining scroll animation offset from RecyclerView 1631 View focusView = findViewByPosition(mFocusPosition); 1632 if (focusView != null) { 1633 delta = mWindowAlignment.mainAxis().getSystemScrollPos(mScrollOffsetPrimary 1634 + getViewCenter(focusView), false, false) - mScrollOffsetPrimary; 1635 deltaSecondary = mWindowAlignment.secondAxis().getSystemScrollPos( 1636 mScrollOffsetSecondary + getViewCenterSecondary(focusView), 1637 false, false) - mScrollOffsetSecondary; 1638 } 1639 } 1640 1641 boolean hadFocus = mBaseGridView.hasFocus(); 1642 int savedFocusPos = mFocusPosition; 1643 if (mInFastRelayout = layoutInit()) { 1644 fastRelayout(); 1645 // appends items till focus position. 1646 if (mFocusPosition != NO_POSITION) { 1647 View focusView = findViewByPosition(mFocusPosition); 1648 if (focusView != null) { 1649 if (scrollToFocus) { 1650 scrollToView(focusView, false); 1651 } 1652 if (hadFocus) { 1653 focusView.requestFocus(); 1654 } 1655 } 1656 } 1657 } else { 1658 mInLayoutSearchFocus = hadFocus; 1659 if (mFocusPosition != NO_POSITION) { 1660 // appends items till focus position. 1661 while (appendOneColumnVisibleItems() 1662 && findViewByPosition(mFocusPosition) == null) ; 1663 } 1664 // multiple rounds: scrollToView of first round may drag first/last child into 1665 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1666 int oldFirstVisible; 1667 int oldLastVisible; 1668 do { 1669 updateScrollMin(); 1670 updateScrollMax(); 1671 oldFirstVisible = mGrid.getFirstVisibleIndex(); 1672 oldLastVisible = mGrid.getLastVisibleIndex(); 1673 View focusView = findViewByPosition(mFocusPosition); 1674 // we need force to initialize the child view's position 1675 scrollToView(focusView, false); 1676 if (focusView != null && hadFocus) { 1677 focusView.requestFocus(); 1678 } 1679 appendVisibleItems(); 1680 prependVisibleItems(); 1681 removeInvisibleViewsAtFront(); 1682 removeInvisibleViewsAtEnd(); 1683 } while (mGrid.getFirstVisibleIndex() != oldFirstVisible || 1684 mGrid.getLastVisibleIndex() != oldLastVisible); 1685 } 1686 1687 if (scrollToFocus) { 1688 scrollDirectionPrimary(-delta); 1689 scrollDirectionSecondary(-deltaSecondary); 1690 } 1691 appendVisibleItems(); 1692 prependVisibleItems(); 1693 removeInvisibleViewsAtFront(); 1694 removeInvisibleViewsAtEnd(); 1695 1696 if (DEBUG) { 1697 StringWriter sw = new StringWriter(); 1698 PrintWriter pw = new PrintWriter(sw); 1699 mGrid.debugPrint(pw); 1700 Log.d(getTag(), sw.toString()); 1701 } 1702 1703 if (mRowSecondarySizeRefresh) { 1704 mRowSecondarySizeRefresh = false; 1705 } else { 1706 updateRowSecondarySizeRefresh(); 1707 } 1708 1709 // For fastRelayout, only dispatch event when focus position changes. 1710 if (mInFastRelayout && mFocusPosition != savedFocusPos) { 1711 dispatchChildSelected(); 1712 } else if (!mInFastRelayout && mInLayoutSearchFocus) { 1713 // For full layout we dispatchChildSelected() in createItem() unless searched all 1714 // children and found none is focusable then dispatchChildSelected() here. 1715 dispatchChildSelected(); 1716 } 1717 1718 mInLayout = false; 1719 leaveContext(); 1720 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1721 } 1722 1723 private void offsetChildrenSecondary(int increment) { 1724 final int childCount = getChildCount(); 1725 if (mOrientation == HORIZONTAL) { 1726 for (int i = 0; i < childCount; i++) { 1727 getChildAt(i).offsetTopAndBottom(increment); 1728 } 1729 } else { 1730 for (int i = 0; i < childCount; i++) { 1731 getChildAt(i).offsetLeftAndRight(increment); 1732 } 1733 } 1734 } 1735 1736 private void offsetChildrenPrimary(int increment) { 1737 final int childCount = getChildCount(); 1738 if (mOrientation == VERTICAL) { 1739 for (int i = 0; i < childCount; i++) { 1740 getChildAt(i).offsetTopAndBottom(increment); 1741 } 1742 } else { 1743 for (int i = 0; i < childCount; i++) { 1744 getChildAt(i).offsetLeftAndRight(increment); 1745 } 1746 } 1747 } 1748 1749 @Override 1750 public int scrollHorizontallyBy(int dx, Recycler recycler, RecyclerView.State state) { 1751 if (DEBUG) Log.v(getTag(), "scrollHorizontallyBy " + dx); 1752 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1753 return 0; 1754 } 1755 saveContext(recycler, state); 1756 mInScroll = true; 1757 int result; 1758 if (mOrientation == HORIZONTAL) { 1759 result = scrollDirectionPrimary(dx); 1760 } else { 1761 result = scrollDirectionSecondary(dx); 1762 } 1763 leaveContext(); 1764 mInScroll = false; 1765 return result; 1766 } 1767 1768 @Override 1769 public int scrollVerticallyBy(int dy, Recycler recycler, RecyclerView.State state) { 1770 if (DEBUG) Log.v(getTag(), "scrollVerticallyBy " + dy); 1771 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1772 return 0; 1773 } 1774 mInScroll = true; 1775 saveContext(recycler, state); 1776 int result; 1777 if (mOrientation == VERTICAL) { 1778 result = scrollDirectionPrimary(dy); 1779 } else { 1780 result = scrollDirectionSecondary(dy); 1781 } 1782 leaveContext(); 1783 mInScroll = false; 1784 return result; 1785 } 1786 1787 // scroll in main direction may add/prune views 1788 private int scrollDirectionPrimary(int da) { 1789 if (TRACE) TraceHelper.beginSection("scrollPrimary"); 1790 boolean isMaxUnknown = false, isMinUnknown = false; 1791 int minScroll = 0, maxScroll = 0; 1792 if (da > 0) { 1793 isMaxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1794 if (!isMaxUnknown) { 1795 maxScroll = mWindowAlignment.mainAxis().getMaxScroll(); 1796 if (mScrollOffsetPrimary + da > maxScroll) { 1797 da = maxScroll - mScrollOffsetPrimary; 1798 } 1799 } 1800 } else if (da < 0) { 1801 isMinUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1802 if (!isMinUnknown) { 1803 minScroll = mWindowAlignment.mainAxis().getMinScroll(); 1804 if (mScrollOffsetPrimary + da < minScroll) { 1805 da = minScroll - mScrollOffsetPrimary; 1806 } 1807 } 1808 } 1809 if (da == 0) { 1810 if (TRACE) TraceHelper.endSection(); 1811 return 0; 1812 } 1813 offsetChildrenPrimary(-da); 1814 mScrollOffsetPrimary += da; 1815 if (mInLayout) { 1816 if (TRACE) TraceHelper.endSection(); 1817 return da; 1818 } 1819 1820 int childCount = getChildCount(); 1821 boolean updated; 1822 1823 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1824 prependVisibleItems(); 1825 } else { 1826 appendVisibleItems(); 1827 } 1828 updated = getChildCount() > childCount; 1829 childCount = getChildCount(); 1830 1831 if (TRACE) TraceHelper.beginSection("remove"); 1832 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1833 removeInvisibleViewsAtEnd(); 1834 } else { 1835 removeInvisibleViewsAtFront(); 1836 } 1837 if (TRACE) TraceHelper.endSection(); 1838 updated |= getChildCount() < childCount; 1839 if (updated) { 1840 updateRowSecondarySizeRefresh(); 1841 } 1842 1843 mBaseGridView.invalidate(); 1844 if (TRACE) TraceHelper.endSection(); 1845 return da; 1846 } 1847 1848 // scroll in second direction will not add/prune views 1849 private int scrollDirectionSecondary(int dy) { 1850 if (dy == 0) { 1851 return 0; 1852 } 1853 offsetChildrenSecondary(-dy); 1854 mScrollOffsetSecondary += dy; 1855 mBaseGridView.invalidate(); 1856 return dy; 1857 } 1858 1859 private void updateScrollMax() { 1860 int highVisiblePos = (!mReverseFlowPrimary) ? mGrid.getLastVisibleIndex() 1861 : mGrid.getFirstVisibleIndex(); 1862 int highMaxPos = (!mReverseFlowPrimary) ? mState.getItemCount() - 1 : 0; 1863 if (highVisiblePos < 0) { 1864 return; 1865 } 1866 final boolean highAvailable = highVisiblePos == highMaxPos; 1867 final boolean maxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1868 if (!highAvailable && maxUnknown) { 1869 return; 1870 } 1871 int maxEdge = mGrid.findRowMax(true, sTwoInts) + mScrollOffsetPrimary; 1872 int rowIndex = sTwoInts[0]; 1873 int pos = sTwoInts[1]; 1874 int savedMaxEdge = mWindowAlignment.mainAxis().getMaxEdge(); 1875 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1876 int maxScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1877 mWindowAlignment.mainAxis().setMaxEdge(savedMaxEdge); 1878 1879 if (highAvailable) { 1880 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1881 mWindowAlignment.mainAxis().setMaxScroll(maxScroll); 1882 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge + 1883 " scrollMax to " + maxScroll); 1884 } else { 1885 mWindowAlignment.mainAxis().invalidateScrollMax(); 1886 if (DEBUG) Log.v(getTag(), "Invalidate scrollMax since it should be " 1887 + "greater than " + maxScroll); 1888 } 1889 } 1890 1891 private void updateScrollMin() { 1892 int lowVisiblePos = (!mReverseFlowPrimary) ? mGrid.getFirstVisibleIndex() 1893 : mGrid.getLastVisibleIndex(); 1894 int lowMinPos = (!mReverseFlowPrimary) ? 0 : mState.getItemCount() - 1; 1895 if (lowVisiblePos < 0) { 1896 return; 1897 } 1898 final boolean lowAvailable = lowVisiblePos == lowMinPos; 1899 final boolean minUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1900 if (!lowAvailable && minUnknown) { 1901 return; 1902 } 1903 int minEdge = mGrid.findRowMin(false, sTwoInts) + mScrollOffsetPrimary; 1904 int rowIndex = sTwoInts[0]; 1905 int pos = sTwoInts[1]; 1906 int savedMinEdge = mWindowAlignment.mainAxis().getMinEdge(); 1907 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1908 int minScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1909 mWindowAlignment.mainAxis().setMinEdge(savedMinEdge); 1910 1911 if (lowAvailable) { 1912 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1913 mWindowAlignment.mainAxis().setMinScroll(minScroll); 1914 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge + 1915 " scrollMin to " + minScroll); 1916 } else { 1917 mWindowAlignment.mainAxis().invalidateScrollMin(); 1918 if (DEBUG) Log.v(getTag(), "Invalidate scrollMin, since it should be " 1919 + "less than " + minScroll); 1920 } 1921 } 1922 1923 private void updateScrollSecondAxis() { 1924 mWindowAlignment.secondAxis().setMinEdge(0); 1925 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1926 } 1927 1928 private void initScrollController() { 1929 mWindowAlignment.reset(); 1930 mWindowAlignment.horizontal.setSize(getWidth()); 1931 mWindowAlignment.vertical.setSize(getHeight()); 1932 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1933 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1934 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1935 mScrollOffsetPrimary = -mWindowAlignment.mainAxis().getPaddingLow(); 1936 mScrollOffsetSecondary = -mWindowAlignment.secondAxis().getPaddingLow(); 1937 1938 if (DEBUG) { 1939 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1940 + " mWindowAlignment " + mWindowAlignment 1941 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1942 } 1943 } 1944 1945 private void updateScrollController() { 1946 // mScrollOffsetPrimary and mScrollOffsetSecondary includes the padding. 1947 // e.g. when topPadding is 16 for horizontal grid view, the initial 1948 // mScrollOffsetSecondary is -16. fastRelayout() put views based on offsets(not padding), 1949 // when padding changes to 20, we also need update mScrollOffsetSecondary to -20 before 1950 // fastRelayout() is performed 1951 int paddingPrimaryDiff, paddingSecondaryDiff; 1952 if (mOrientation == HORIZONTAL) { 1953 paddingPrimaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1954 paddingSecondaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1955 } else { 1956 paddingPrimaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1957 paddingSecondaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1958 } 1959 mScrollOffsetPrimary -= paddingPrimaryDiff; 1960 mScrollOffsetSecondary -= paddingSecondaryDiff; 1961 1962 mWindowAlignment.horizontal.setSize(getWidth()); 1963 mWindowAlignment.vertical.setSize(getHeight()); 1964 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1965 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1966 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1967 1968 if (DEBUG) { 1969 Log.v(getTag(), "updateScrollController mSizePrimary " + mSizePrimary 1970 + " mWindowAlignment " + mWindowAlignment 1971 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1972 } 1973 } 1974 1975 public void setSelection(RecyclerView parent, int position, 1976 int primaryScrollExtra) { 1977 setSelection(parent, position, false, primaryScrollExtra); 1978 } 1979 1980 public void setSelectionSmooth(RecyclerView parent, int position) { 1981 setSelection(parent, position, true, 0); 1982 } 1983 1984 public int getSelection() { 1985 return mFocusPosition; 1986 } 1987 1988 public void setSelection(RecyclerView parent, int position, boolean smooth, 1989 int primaryScrollExtra) { 1990 if (mFocusPosition != position && position != NO_POSITION 1991 || primaryScrollExtra != mPrimaryScrollExtra) { 1992 scrollToSelection(parent, position, smooth, primaryScrollExtra); 1993 } 1994 } 1995 1996 private void scrollToSelection(RecyclerView parent, int position, boolean smooth, 1997 int primaryScrollExtra) { 1998 if (TRACE) TraceHelper.beginSection("scrollToSelection"); 1999 mPrimaryScrollExtra = primaryScrollExtra; 2000 View view = findViewByPosition(position); 2001 if (view != null) { 2002 mInSelection = true; 2003 scrollToView(view, smooth); 2004 mInSelection = false; 2005 } else { 2006 mFocusPosition = position; 2007 mFocusPositionOffset = 0; 2008 if (!mLayoutEnabled) { 2009 return; 2010 } 2011 if (smooth) { 2012 if (!hasDoneFirstLayout()) { 2013 Log.w(getTag(), "setSelectionSmooth should " + 2014 "not be called before first layout pass"); 2015 return; 2016 } 2017 startPositionSmoothScroller(position); 2018 } else { 2019 mForceFullLayout = true; 2020 parent.requestLayout(); 2021 } 2022 } 2023 if (TRACE) TraceHelper.endSection(); 2024 } 2025 2026 void startPositionSmoothScroller(int position) { 2027 LinearSmoothScroller linearSmoothScroller = new GridLinearSmoothScroller() { 2028 @Override 2029 public PointF computeScrollVectorForPosition(int targetPosition) { 2030 if (getChildCount() == 0) { 2031 return null; 2032 } 2033 final int firstChildPos = getPosition(getChildAt(0)); 2034 // TODO We should be able to deduce direction from bounds of current and target 2035 // focus, rather than making assumptions about positions and directionality 2036 final boolean isStart = mReverseFlowPrimary ? targetPosition > firstChildPos 2037 : targetPosition < firstChildPos; 2038 final int direction = isStart ? -1 : 1; 2039 if (mOrientation == HORIZONTAL) { 2040 return new PointF(direction, 0); 2041 } else { 2042 return new PointF(0, direction); 2043 } 2044 } 2045 2046 }; 2047 linearSmoothScroller.setTargetPosition(position); 2048 startSmoothScroll(linearSmoothScroller); 2049 } 2050 2051 private void processPendingMovement(boolean forward) { 2052 if (forward ? hasCreatedLastItem() : hasCreatedFirstItem()) { 2053 return; 2054 } 2055 if (mPendingMoveSmoothScroller == null) { 2056 // Stop existing scroller and create a new PendingMoveSmoothScroller. 2057 mBaseGridView.stopScroll(); 2058 PendingMoveSmoothScroller linearSmoothScroller = new PendingMoveSmoothScroller( 2059 forward ? 1 : -1, mNumRows > 1); 2060 mFocusPositionOffset = 0; 2061 startSmoothScroll(linearSmoothScroller); 2062 if (linearSmoothScroller.isRunning()) { 2063 mPendingMoveSmoothScroller = linearSmoothScroller; 2064 } 2065 } else { 2066 if (forward) { 2067 mPendingMoveSmoothScroller.increasePendingMoves(); 2068 } else { 2069 mPendingMoveSmoothScroller.decreasePendingMoves(); 2070 } 2071 } 2072 } 2073 2074 @Override 2075 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 2076 if (DEBUG) Log.v(getTag(), "onItemsAdded positionStart " 2077 + positionStart + " itemCount " + itemCount); 2078 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2079 int pos = mFocusPosition + mFocusPositionOffset; 2080 if (positionStart <= pos) { 2081 mFocusPositionOffset += itemCount; 2082 } 2083 } 2084 mChildrenStates.clear(); 2085 } 2086 2087 @Override 2088 public void onItemsChanged(RecyclerView recyclerView) { 2089 if (DEBUG) Log.v(getTag(), "onItemsChanged"); 2090 mFocusPositionOffset = 0; 2091 mChildrenStates.clear(); 2092 } 2093 2094 @Override 2095 public void onItemsRemoved(RecyclerView recyclerView, int positionStart, int itemCount) { 2096 if (DEBUG) Log.v(getTag(), "onItemsRemoved positionStart " 2097 + positionStart + " itemCount " + itemCount); 2098 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2099 int pos = mFocusPosition + mFocusPositionOffset; 2100 if (positionStart <= pos) { 2101 if (positionStart + itemCount > pos) { 2102 // stop updating offset after the focus item was removed 2103 mFocusPositionOffset = Integer.MIN_VALUE; 2104 } else { 2105 mFocusPositionOffset -= itemCount; 2106 } 2107 } 2108 } 2109 mChildrenStates.clear(); 2110 } 2111 2112 @Override 2113 public void onItemsMoved(RecyclerView recyclerView, int fromPosition, int toPosition, 2114 int itemCount) { 2115 if (DEBUG) Log.v(getTag(), "onItemsMoved fromPosition " 2116 + fromPosition + " toPosition " + toPosition); 2117 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2118 int pos = mFocusPosition + mFocusPositionOffset; 2119 if (fromPosition <= pos && pos < fromPosition + itemCount) { 2120 // moved items include focused position 2121 mFocusPositionOffset += toPosition - fromPosition; 2122 } else if (fromPosition < pos && toPosition > pos - itemCount) { 2123 // move items before focus position to after focused position 2124 mFocusPositionOffset -= itemCount; 2125 } else if (fromPosition > pos && toPosition < pos) { 2126 // move items after focus position to before focused position 2127 mFocusPositionOffset += itemCount; 2128 } 2129 } 2130 mChildrenStates.clear(); 2131 } 2132 2133 @Override 2134 public void onItemsUpdated(RecyclerView recyclerView, int positionStart, int itemCount) { 2135 if (DEBUG) Log.v(getTag(), "onItemsUpdated positionStart " 2136 + positionStart + " itemCount " + itemCount); 2137 for (int i = positionStart, end = positionStart + itemCount; i < end; i++) { 2138 mChildrenStates.remove(i); 2139 } 2140 } 2141 2142 @Override 2143 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 2144 if (mFocusSearchDisabled) { 2145 return true; 2146 } 2147 if (getPositionByView(child) == NO_POSITION) { 2148 // This shouldn't happen, but in case it does be sure not to attempt a 2149 // scroll to a view whose item has been removed. 2150 return true; 2151 } 2152 if (!mInLayout && !mInSelection && !mInScroll) { 2153 scrollToView(child, true); 2154 } 2155 return true; 2156 } 2157 2158 @Override 2159 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 2160 boolean immediate) { 2161 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 2162 return false; 2163 } 2164 2165 int getScrollOffsetX() { 2166 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 2167 } 2168 2169 int getScrollOffsetY() { 2170 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 2171 } 2172 2173 public void getViewSelectedOffsets(View view, int[] offsets) { 2174 if (mOrientation == HORIZONTAL) { 2175 offsets[0] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2176 offsets[1] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2177 } else { 2178 offsets[1] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2179 offsets[0] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2180 } 2181 } 2182 2183 private int getPrimarySystemScrollPosition(View view) { 2184 final int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 2185 final int viewMin = getViewMin(view); 2186 final int viewMax = getViewMax(view); 2187 // TODO: change to use State object in onRequestChildFocus() 2188 boolean isMin, isMax; 2189 if (!mReverseFlowPrimary) { 2190 isMin = mGrid.getFirstVisibleIndex() == 0; 2191 isMax = mGrid.getLastVisibleIndex() == (mState == null ? 2192 getItemCount() : mState.getItemCount()) - 1; 2193 } else { 2194 isMax = mGrid.getFirstVisibleIndex() == 0; 2195 isMin = mGrid.getLastVisibleIndex() == (mState == null ? 2196 getItemCount() : mState.getItemCount()) - 1; 2197 } 2198 for (int i = getChildCount() - 1; (isMin || isMax) && i >= 0; i--) { 2199 View v = getChildAt(i); 2200 if (v == view || v == null) { 2201 continue; 2202 } 2203 if (isMin && getViewMin(v) < viewMin) { 2204 isMin = false; 2205 } 2206 if (isMax && getViewMax(v) > viewMax) { 2207 isMax = false; 2208 } 2209 } 2210 return mWindowAlignment.mainAxis().getSystemScrollPos(viewCenterPrimary, isMin, isMax); 2211 } 2212 2213 private int getSecondarySystemScrollPosition(View view) { 2214 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 2215 int pos = getPositionByView(view); 2216 Grid.Location location = mGrid.getLocation(pos); 2217 final int row = location.row; 2218 final boolean isMin, isMax; 2219 if (!mReverseFlowSecondary) { 2220 isMin = row == 0; 2221 isMax = row == mGrid.getNumRows() - 1; 2222 } else { 2223 isMax = row == 0; 2224 isMin = row == mGrid.getNumRows() - 1; 2225 } 2226 return mWindowAlignment.secondAxis().getSystemScrollPos(viewCenterSecondary, isMin, isMax); 2227 } 2228 2229 /** 2230 * Scroll to a given child view and change mFocusPosition. 2231 */ 2232 private void scrollToView(View view, boolean smooth) { 2233 int newFocusPosition = getPositionByView(view); 2234 if (newFocusPosition != mFocusPosition) { 2235 mFocusPosition = newFocusPosition; 2236 mFocusPositionOffset = 0; 2237 if (!mInLayout) { 2238 dispatchChildSelected(); 2239 } 2240 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 2241 mBaseGridView.invalidate(); 2242 } 2243 } 2244 if (view == null) { 2245 return; 2246 } 2247 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 2248 // transfer focus to the child if it does not have focus yet (e.g. triggered 2249 // by setSelection()) 2250 view.requestFocus(); 2251 } 2252 if (!mScrollEnabled && smooth) { 2253 return; 2254 } 2255 if (getScrollPosition(view, sTwoInts)) { 2256 scrollGrid(sTwoInts[0], sTwoInts[1], smooth); 2257 } 2258 } 2259 2260 private boolean getScrollPosition(View view, int[] deltas) { 2261 switch (mFocusScrollStrategy) { 2262 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2263 default: 2264 return getAlignedPosition(view, deltas); 2265 case BaseGridView.FOCUS_SCROLL_ITEM: 2266 case BaseGridView.FOCUS_SCROLL_PAGE: 2267 return getNoneAlignedPosition(view, deltas); 2268 } 2269 } 2270 2271 private boolean getNoneAlignedPosition(View view, int[] deltas) { 2272 int pos = getPositionByView(view); 2273 int viewMin = getViewMin(view); 2274 int viewMax = getViewMax(view); 2275 // we either align "firstView" to left/top padding edge 2276 // or align "lastView" to right/bottom padding edge 2277 View firstView = null; 2278 View lastView = null; 2279 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 2280 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 2281 final int row = mGrid.getRowIndex(pos); 2282 if (viewMin < paddingLow) { 2283 // view enters low padding area: 2284 firstView = view; 2285 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2286 // scroll one "page" left/top, 2287 // align first visible item of the "page" at the low padding edge. 2288 while (prependOneColumnVisibleItems()) { 2289 CircularIntArray positions = 2290 mGrid.getItemPositionsInRows(mGrid.getFirstVisibleIndex(), pos)[row]; 2291 firstView = findViewByPosition(positions.get(0)); 2292 if (viewMax - getViewMin(firstView) > clientSize) { 2293 if (positions.size() > 2) { 2294 firstView = findViewByPosition(positions.get(2)); 2295 } 2296 break; 2297 } 2298 } 2299 } 2300 } else if (viewMax > clientSize + paddingLow) { 2301 // view enters high padding area: 2302 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2303 // scroll whole one page right/bottom, align view at the low padding edge. 2304 firstView = view; 2305 do { 2306 CircularIntArray positions = 2307 mGrid.getItemPositionsInRows(pos, mGrid.getLastVisibleIndex())[row]; 2308 lastView = findViewByPosition(positions.get(positions.size() - 1)); 2309 if (getViewMax(lastView) - viewMin > clientSize) { 2310 lastView = null; 2311 break; 2312 } 2313 } while (appendOneColumnVisibleItems()); 2314 if (lastView != null) { 2315 // however if we reached end, we should align last view. 2316 firstView = null; 2317 } 2318 } else { 2319 lastView = view; 2320 } 2321 } 2322 int scrollPrimary = 0; 2323 int scrollSecondary = 0; 2324 if (firstView != null) { 2325 scrollPrimary = getViewMin(firstView) - paddingLow; 2326 } else if (lastView != null) { 2327 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 2328 } 2329 View secondaryAlignedView; 2330 if (firstView != null) { 2331 secondaryAlignedView = firstView; 2332 } else if (lastView != null) { 2333 secondaryAlignedView = lastView; 2334 } else { 2335 secondaryAlignedView = view; 2336 } 2337 scrollSecondary = getSecondarySystemScrollPosition(secondaryAlignedView); 2338 scrollSecondary -= mScrollOffsetSecondary; 2339 if (scrollPrimary != 0 || scrollSecondary != 0) { 2340 deltas[0] = scrollPrimary; 2341 deltas[1] = scrollSecondary; 2342 return true; 2343 } 2344 return false; 2345 } 2346 2347 private boolean getAlignedPosition(View view, int[] deltas) { 2348 int scrollPrimary = getPrimarySystemScrollPosition(view); 2349 int scrollSecondary = getSecondarySystemScrollPosition(view); 2350 if (DEBUG) { 2351 Log.v(getTag(), "getAlignedPosition " + scrollPrimary + " " + scrollSecondary 2352 + " " + mPrimaryScrollExtra + " " + mWindowAlignment); 2353 Log.v(getTag(), "getAlignedPosition " + mScrollOffsetPrimary + " " + mScrollOffsetSecondary); 2354 } 2355 scrollPrimary -= mScrollOffsetPrimary; 2356 scrollSecondary -= mScrollOffsetSecondary; 2357 scrollPrimary += mPrimaryScrollExtra; 2358 if (scrollPrimary != 0 || scrollSecondary != 0) { 2359 deltas[0] = scrollPrimary; 2360 deltas[1] = scrollSecondary; 2361 return true; 2362 } 2363 return false; 2364 } 2365 2366 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 2367 if (mInLayout) { 2368 scrollDirectionPrimary(scrollPrimary); 2369 scrollDirectionSecondary(scrollSecondary); 2370 } else { 2371 int scrollX; 2372 int scrollY; 2373 if (mOrientation == HORIZONTAL) { 2374 scrollX = scrollPrimary; 2375 scrollY = scrollSecondary; 2376 } else { 2377 scrollX = scrollSecondary; 2378 scrollY = scrollPrimary; 2379 } 2380 if (smooth) { 2381 mBaseGridView.smoothScrollBy(scrollX, scrollY); 2382 } else { 2383 mBaseGridView.scrollBy(scrollX, scrollY); 2384 } 2385 } 2386 } 2387 2388 public void setPruneChild(boolean pruneChild) { 2389 if (mPruneChild != pruneChild) { 2390 mPruneChild = pruneChild; 2391 if (mPruneChild) { 2392 requestLayout(); 2393 } 2394 } 2395 } 2396 2397 public boolean getPruneChild() { 2398 return mPruneChild; 2399 } 2400 2401 public void setScrollEnabled(boolean scrollEnabled) { 2402 if (mScrollEnabled != scrollEnabled) { 2403 mScrollEnabled = scrollEnabled; 2404 if (mScrollEnabled && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED 2405 && mFocusPosition != NO_POSITION) { 2406 scrollToSelection(mBaseGridView, mFocusPosition, true, mPrimaryScrollExtra); 2407 } 2408 } 2409 } 2410 2411 public boolean isScrollEnabled() { 2412 return mScrollEnabled; 2413 } 2414 2415 private int findImmediateChildIndex(View view) { 2416 while (view != null && view != mBaseGridView) { 2417 int index = mBaseGridView.indexOfChild(view); 2418 if (index >= 0) { 2419 return index; 2420 } 2421 view = (View) view.getParent(); 2422 } 2423 return NO_POSITION; 2424 } 2425 2426 void setFocusSearchDisabled(boolean disabled) { 2427 mFocusSearchDisabled = disabled; 2428 } 2429 2430 boolean isFocusSearchDisabled() { 2431 return mFocusSearchDisabled; 2432 } 2433 2434 @Override 2435 public View onInterceptFocusSearch(View focused, int direction) { 2436 if (mFocusSearchDisabled) { 2437 return focused; 2438 } 2439 return null; 2440 } 2441 2442 boolean hasPreviousViewInSameRow(int pos) { 2443 if (mGrid == null || pos == NO_POSITION || mGrid.getFirstVisibleIndex() < 0) { 2444 return false; 2445 } 2446 if (mGrid.getFirstVisibleIndex() > 0) { 2447 return true; 2448 } 2449 final int focusedRow = mGrid.getLocation(pos).row; 2450 for (int i = getChildCount() - 1; i >= 0; i--) { 2451 int position = getPositionByIndex(i); 2452 Grid.Location loc = mGrid.getLocation(position); 2453 if (loc != null && loc.row == focusedRow) { 2454 if (position < pos) { 2455 return true; 2456 } 2457 } 2458 } 2459 return false; 2460 } 2461 2462 @Override 2463 public boolean onAddFocusables(RecyclerView recyclerView, 2464 ArrayList<View> views, int direction, int focusableMode) { 2465 if (mFocusSearchDisabled) { 2466 return true; 2467 } 2468 // If this viewgroup or one of its children currently has focus then we 2469 // consider our children for focus searching in main direction on the same row. 2470 // If this viewgroup has no focus and using focus align, we want the system 2471 // to ignore our children and pass focus to the viewgroup, which will pass 2472 // focus on to its children appropriately. 2473 // If this viewgroup has no focus and not using focus align, we want to 2474 // consider the child that does not overlap with padding area. 2475 if (recyclerView.hasFocus()) { 2476 final int movement = getMovement(direction); 2477 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2478 // Move on secondary direction uses default addFocusables(). 2479 return false; 2480 } 2481 if (mPendingMoveSmoothScroller != null) { 2482 // don't find next focusable if has pending movement. 2483 return true; 2484 } 2485 final View focused = recyclerView.findFocus(); 2486 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2487 // Add focusables of focused item. 2488 if (focusedPos != NO_POSITION) { 2489 findViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2490 } 2491 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2492 mGrid.getLocation(focusedPos).row : NO_POSITION; 2493 // Add focusables of next neighbor of same row on the focus search direction. 2494 if (mGrid != null) { 2495 final int focusableCount = views.size(); 2496 for (int i = 0, count = getChildCount(); i < count; i++) { 2497 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2498 final View child = getChildAt(index); 2499 if (child.getVisibility() != View.VISIBLE || !child.hasFocusable()) { 2500 continue; 2501 } 2502 int position = getPositionByIndex(index); 2503 Grid.Location loc = mGrid.getLocation(position); 2504 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2505 if (focusedPos == NO_POSITION || 2506 (movement == NEXT_ITEM && position > focusedPos) 2507 || (movement == PREV_ITEM && position < focusedPos)) { 2508 child.addFocusables(views, direction, focusableMode); 2509 if (views.size() > focusableCount) { 2510 break; 2511 } 2512 } 2513 } 2514 } 2515 } 2516 } else { 2517 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2518 // adding views not overlapping padding area to avoid scrolling in gaining focus 2519 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2520 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2521 int focusableCount = views.size(); 2522 for (int i = 0, count = getChildCount(); i < count; i++) { 2523 View child = getChildAt(i); 2524 if (child.getVisibility() == View.VISIBLE) { 2525 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2526 child.addFocusables(views, direction, focusableMode); 2527 } 2528 } 2529 } 2530 // if we cannot find any, then just add all children. 2531 if (views.size() == focusableCount) { 2532 for (int i = 0, count = getChildCount(); i < count; i++) { 2533 View child = getChildAt(i); 2534 if (child.getVisibility() == View.VISIBLE) { 2535 child.addFocusables(views, direction, focusableMode); 2536 } 2537 } 2538 if (views.size() != focusableCount) { 2539 return true; 2540 } 2541 } else { 2542 return true; 2543 } 2544 // if still cannot find any, fall through and add itself 2545 } 2546 if (recyclerView.isFocusable()) { 2547 views.add(recyclerView); 2548 } 2549 } 2550 return true; 2551 } 2552 2553 private boolean hasCreatedLastItem() { 2554 int count = mState.getItemCount(); 2555 return count == 0 || findViewByPosition(count - 1) != null; 2556 } 2557 2558 private boolean hasCreatedFirstItem() { 2559 int count = mState.getItemCount(); 2560 return count == 0 || findViewByPosition(0) != null; 2561 } 2562 2563 boolean canScrollTo(View view) { 2564 return view.getVisibility() == View.VISIBLE && (!hasFocus() || view.hasFocusable()); 2565 } 2566 2567 @Override 2568 public View onFocusSearchFailed(View focused, int direction, Recycler recycler, 2569 RecyclerView.State state) { 2570 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2571 2572 View view = null; 2573 int movement = getMovement(direction); 2574 final boolean isScroll = mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE; 2575 saveContext(recycler, state); 2576 if (movement == NEXT_ITEM) { 2577 if (isScroll || !mFocusOutEnd) { 2578 view = focused; 2579 } 2580 if (mScrollEnabled && !hasCreatedLastItem()) { 2581 processPendingMovement(true); 2582 view = focused; 2583 } 2584 } else if (movement == PREV_ITEM) { 2585 if (isScroll || !mFocusOutFront) { 2586 view = focused; 2587 } 2588 if (mScrollEnabled && !hasCreatedFirstItem()) { 2589 processPendingMovement(false); 2590 view = focused; 2591 } 2592 } 2593 leaveContext(); 2594 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed returning view " + view); 2595 return view; 2596 } 2597 2598 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2599 Rect previouslyFocusedRect) { 2600 switch (mFocusScrollStrategy) { 2601 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2602 default: 2603 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2604 direction, previouslyFocusedRect); 2605 case BaseGridView.FOCUS_SCROLL_PAGE: 2606 case BaseGridView.FOCUS_SCROLL_ITEM: 2607 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2608 direction, previouslyFocusedRect); 2609 } 2610 } 2611 2612 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2613 int direction, Rect previouslyFocusedRect) { 2614 View view = findViewByPosition(mFocusPosition); 2615 if (view != null) { 2616 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2617 if (!result && DEBUG) { 2618 Log.w(getTag(), "failed to request focus on " + view); 2619 } 2620 return result; 2621 } 2622 return false; 2623 } 2624 2625 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2626 int direction, Rect previouslyFocusedRect) { 2627 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2628 int index; 2629 int increment; 2630 int end; 2631 int count = getChildCount(); 2632 if ((direction & View.FOCUS_FORWARD) != 0) { 2633 index = 0; 2634 increment = 1; 2635 end = count; 2636 } else { 2637 index = count - 1; 2638 increment = -1; 2639 end = -1; 2640 } 2641 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2642 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2643 for (int i = index; i != end; i += increment) { 2644 View child = getChildAt(i); 2645 if (child.getVisibility() == View.VISIBLE) { 2646 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2647 if (child.requestFocus(direction, previouslyFocusedRect)) { 2648 return true; 2649 } 2650 } 2651 } 2652 } 2653 return false; 2654 } 2655 2656 private final static int PREV_ITEM = 0; 2657 private final static int NEXT_ITEM = 1; 2658 private final static int PREV_ROW = 2; 2659 private final static int NEXT_ROW = 3; 2660 2661 private int getMovement(int direction) { 2662 int movement = View.FOCUS_LEFT; 2663 2664 if (mOrientation == HORIZONTAL) { 2665 switch(direction) { 2666 case View.FOCUS_LEFT: 2667 movement = (!mReverseFlowPrimary) ? PREV_ITEM : NEXT_ITEM; 2668 break; 2669 case View.FOCUS_RIGHT: 2670 movement = (!mReverseFlowPrimary) ? NEXT_ITEM : PREV_ITEM; 2671 break; 2672 case View.FOCUS_UP: 2673 movement = PREV_ROW; 2674 break; 2675 case View.FOCUS_DOWN: 2676 movement = NEXT_ROW; 2677 break; 2678 } 2679 } else if (mOrientation == VERTICAL) { 2680 switch(direction) { 2681 case View.FOCUS_LEFT: 2682 movement = (!mReverseFlowPrimary) ? PREV_ROW : NEXT_ROW; 2683 break; 2684 case View.FOCUS_RIGHT: 2685 movement = (!mReverseFlowPrimary) ? NEXT_ROW : PREV_ROW; 2686 break; 2687 case View.FOCUS_UP: 2688 movement = PREV_ITEM; 2689 break; 2690 case View.FOCUS_DOWN: 2691 movement = NEXT_ITEM; 2692 break; 2693 } 2694 } 2695 2696 return movement; 2697 } 2698 2699 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2700 View view = findViewByPosition(mFocusPosition); 2701 if (view == null) { 2702 return i; 2703 } 2704 int focusIndex = recyclerView.indexOfChild(view); 2705 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2706 // drawing order is 0 1 2 3 9 8 7 6 5 4 2707 if (i < focusIndex) { 2708 return i; 2709 } else if (i < childCount - 1) { 2710 return focusIndex + childCount - 1 - i; 2711 } else { 2712 return focusIndex; 2713 } 2714 } 2715 2716 @Override 2717 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2718 RecyclerView.Adapter newAdapter) { 2719 if (DEBUG) Log.v(getTag(), "onAdapterChanged to " + newAdapter); 2720 if (oldAdapter != null) { 2721 discardLayoutInfo(); 2722 mFocusPosition = NO_POSITION; 2723 mFocusPositionOffset = 0; 2724 mChildrenStates.clear(); 2725 } 2726 super.onAdapterChanged(oldAdapter, newAdapter); 2727 } 2728 2729 private void discardLayoutInfo() { 2730 mGrid = null; 2731 mRowSizeSecondary = null; 2732 mRowSecondarySizeRefresh = false; 2733 } 2734 2735 public void setLayoutEnabled(boolean layoutEnabled) { 2736 if (mLayoutEnabled != layoutEnabled) { 2737 mLayoutEnabled = layoutEnabled; 2738 requestLayout(); 2739 } 2740 } 2741 2742 void setChildrenVisibility(int visiblity) { 2743 mChildVisibility = visiblity; 2744 if (mChildVisibility != -1) { 2745 int count = getChildCount(); 2746 for (int i= 0; i < count; i++) { 2747 getChildAt(i).setVisibility(mChildVisibility); 2748 } 2749 } 2750 } 2751 2752 final static class SavedState implements Parcelable { 2753 2754 int index; // index inside adapter of the current view 2755 Bundle childStates = Bundle.EMPTY; 2756 2757 @Override 2758 public void writeToParcel(Parcel out, int flags) { 2759 out.writeInt(index); 2760 out.writeBundle(childStates); 2761 } 2762 2763 @SuppressWarnings("hiding") 2764 public static final Parcelable.Creator<SavedState> CREATOR = 2765 new Parcelable.Creator<SavedState>() { 2766 @Override 2767 public SavedState createFromParcel(Parcel in) { 2768 return new SavedState(in); 2769 } 2770 2771 @Override 2772 public SavedState[] newArray(int size) { 2773 return new SavedState[size]; 2774 } 2775 }; 2776 2777 @Override 2778 public int describeContents() { 2779 return 0; 2780 } 2781 2782 SavedState(Parcel in) { 2783 index = in.readInt(); 2784 childStates = in.readBundle(GridLayoutManager.class.getClassLoader()); 2785 } 2786 2787 SavedState() { 2788 } 2789 } 2790 2791 @Override 2792 public Parcelable onSaveInstanceState() { 2793 if (DEBUG) Log.v(getTag(), "onSaveInstanceState getSelection() " + getSelection()); 2794 SavedState ss = new SavedState(); 2795 for (int i = 0, count = getChildCount(); i < count; i++) { 2796 View view = getChildAt(i); 2797 int position = getPositionByView(view); 2798 if (position != NO_POSITION) { 2799 mChildrenStates.saveOnScreenView(view, position); 2800 } 2801 } 2802 ss.index = getSelection(); 2803 ss.childStates = mChildrenStates.saveAsBundle(); 2804 return ss; 2805 } 2806 2807 void onChildRecycled(RecyclerView.ViewHolder holder) { 2808 final int position = holder.getAdapterPosition(); 2809 if (position != NO_POSITION) { 2810 mChildrenStates.saveOffscreenView(holder.itemView, position); 2811 } 2812 } 2813 2814 @Override 2815 public void onRestoreInstanceState(Parcelable state) { 2816 if (!(state instanceof SavedState)) { 2817 return; 2818 } 2819 SavedState loadingState = (SavedState)state; 2820 mFocusPosition = loadingState.index; 2821 mFocusPositionOffset = 0; 2822 mChildrenStates.loadFromBundle(loadingState.childStates); 2823 mForceFullLayout = true; 2824 requestLayout(); 2825 if (DEBUG) Log.v(getTag(), "onRestoreInstanceState mFocusPosition " + mFocusPosition); 2826 } 2827} 2828