GridLayoutManager.java revision 05fc55725c9881e6a1c11e6dc5ff3f9d7281d491
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 } 715 716 /** 717 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 718 */ 719 public void setRowHeight(int height) { 720 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 721 mRowSizeSecondaryRequested = height; 722 } else { 723 throw new IllegalArgumentException("Invalid row height: " + height); 724 } 725 } 726 727 public void setItemMargin(int margin) { 728 mVerticalMargin = mHorizontalMargin = margin; 729 mMarginPrimary = mMarginSecondary = margin; 730 } 731 732 public void setVerticalMargin(int margin) { 733 if (mOrientation == HORIZONTAL) { 734 mMarginSecondary = mVerticalMargin = margin; 735 } else { 736 mMarginPrimary = mVerticalMargin = margin; 737 } 738 } 739 740 public void setHorizontalMargin(int margin) { 741 if (mOrientation == HORIZONTAL) { 742 mMarginPrimary = mHorizontalMargin = margin; 743 } else { 744 mMarginSecondary = mHorizontalMargin = margin; 745 } 746 } 747 748 public int getVerticalMargin() { 749 return mVerticalMargin; 750 } 751 752 public int getHorizontalMargin() { 753 return mHorizontalMargin; 754 } 755 756 public void setGravity(int gravity) { 757 mGravity = gravity; 758 } 759 760 protected boolean hasDoneFirstLayout() { 761 return mGrid != null; 762 } 763 764 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 765 mChildSelectedListener = listener; 766 } 767 768 void setOnChildLaidOutListener(OnChildLaidOutListener listener) { 769 mChildLaidOutListener = listener; 770 } 771 772 private int getPositionByView(View view) { 773 if (view == null) { 774 return NO_POSITION; 775 } 776 LayoutParams params = (LayoutParams) view.getLayoutParams(); 777 if (params == null || params.isItemRemoved()) { 778 // when item is removed, the position value can be any value. 779 return NO_POSITION; 780 } 781 return params.getViewPosition(); 782 } 783 784 private int getPositionByIndex(int index) { 785 return getPositionByView(getChildAt(index)); 786 } 787 788 private void dispatchChildSelected() { 789 if (mChildSelectedListener == null) { 790 return; 791 } 792 793 if (TRACE) TraceHelper.beginSection("onChildSelected"); 794 View view = mFocusPosition == NO_POSITION ? null : findViewByPosition(mFocusPosition); 795 if (view != null) { 796 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(view); 797 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 798 vh == null? NO_ID: vh.getItemId()); 799 } else { 800 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 801 } 802 if (TRACE) TraceHelper.endSection(); 803 804 // Children may request layout when a child selection event occurs (such as a change of 805 // padding on the current and previously selected rows). 806 // If in layout, a child requesting layout may have been laid out before the selection 807 // callback. 808 // If it was not, the child will be laid out after the selection callback. 809 // If so, the layout request will be honoured though the view system will emit a double- 810 // layout warning. 811 // If not in layout, we may be scrolling in which case the child layout request will be 812 // eaten by recyclerview. Post a requestLayout. 813 if (!mInLayout && !mBaseGridView.isLayoutRequested()) { 814 int childCount = getChildCount(); 815 for (int i = 0; i < childCount; i++) { 816 if (getChildAt(i).isLayoutRequested()) { 817 forceRequestLayout(); 818 break; 819 } 820 } 821 } 822 } 823 824 @Override 825 public boolean canScrollHorizontally() { 826 // We can scroll horizontally if we have horizontal orientation, or if 827 // we are vertical and have more than one column. 828 return mOrientation == HORIZONTAL || mNumRows > 1; 829 } 830 831 @Override 832 public boolean canScrollVertically() { 833 // We can scroll vertically if we have vertical orientation, or if we 834 // are horizontal and have more than one row. 835 return mOrientation == VERTICAL || mNumRows > 1; 836 } 837 838 @Override 839 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 840 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 841 ViewGroup.LayoutParams.WRAP_CONTENT); 842 } 843 844 @Override 845 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 846 return new LayoutParams(context, attrs); 847 } 848 849 @Override 850 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 851 if (lp instanceof LayoutParams) { 852 return new LayoutParams((LayoutParams) lp); 853 } else if (lp instanceof RecyclerView.LayoutParams) { 854 return new LayoutParams((RecyclerView.LayoutParams) lp); 855 } else if (lp instanceof MarginLayoutParams) { 856 return new LayoutParams((MarginLayoutParams) lp); 857 } else { 858 return new LayoutParams(lp); 859 } 860 } 861 862 protected View getViewForPosition(int position) { 863 return mRecycler.getViewForPosition(position); 864 } 865 866 final int getOpticalLeft(View v) { 867 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 868 } 869 870 final int getOpticalRight(View v) { 871 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 872 } 873 874 final int getOpticalTop(View v) { 875 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 876 } 877 878 final int getOpticalBottom(View v) { 879 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 880 } 881 882 private int getViewMin(View v) { 883 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 884 } 885 886 private int getViewMax(View v) { 887 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 888 } 889 890 private int getViewPrimarySize(View view) { 891 LayoutParams p = (LayoutParams) view.getLayoutParams(); 892 return mOrientation == HORIZONTAL ? p.getOpticalWidth(view) : p.getOpticalHeight(view); 893 } 894 895 private int getViewCenter(View view) { 896 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 897 } 898 899 private int getViewCenterSecondary(View view) { 900 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 901 } 902 903 private int getViewCenterX(View v) { 904 LayoutParams p = (LayoutParams) v.getLayoutParams(); 905 return p.getOpticalLeft(v) + p.getAlignX(); 906 } 907 908 private int getViewCenterY(View v) { 909 LayoutParams p = (LayoutParams) v.getLayoutParams(); 910 return p.getOpticalTop(v) + p.getAlignY(); 911 } 912 913 /** 914 * Save Recycler and State for convenience. Must be paired with leaveContext(). 915 */ 916 private void saveContext(Recycler recycler, State state) { 917 if (mRecycler != null || mState != null) { 918 Log.e(TAG, "Recycler information was not released, bug!"); 919 } 920 mRecycler = recycler; 921 mState = state; 922 } 923 924 /** 925 * Discard saved Recycler and State. 926 */ 927 private void leaveContext() { 928 mRecycler = null; 929 mState = null; 930 } 931 932 /** 933 * Re-initialize data structures for a data change or handling invisible 934 * selection. The method tries its best to preserve position information so 935 * that staggered grid looks same before and after re-initialize. 936 * @return true if can fastRelayout() 937 */ 938 private boolean layoutInit() { 939 boolean focusViewWasInTree = mGrid != null && mFocusPosition >= 0 940 && mFocusPosition >= mGrid.getFirstVisibleIndex() 941 && mFocusPosition <= mGrid.getLastVisibleIndex(); 942 final int newItemCount = mState.getItemCount(); 943 if (newItemCount == 0) { 944 mFocusPosition = NO_POSITION; 945 } else if (mFocusPosition >= newItemCount) { 946 mFocusPosition = newItemCount - 1; 947 } else if (mFocusPosition == NO_POSITION && newItemCount > 0) { 948 // if focus position is never set before, initialize it to 0 949 mFocusPosition = 0; 950 } 951 if (!mState.didStructureChange() && mGrid.getFirstVisibleIndex() >= 0 && 952 !mForceFullLayout && mGrid != null && mGrid.getNumRows() == mNumRows) { 953 updateScrollController(); 954 updateScrollSecondAxis(); 955 mGrid.setMargin(mMarginPrimary); 956 if (!focusViewWasInTree && mFocusPosition != NO_POSITION) { 957 mGrid.setStart(mFocusPosition); 958 } 959 return true; 960 } else { 961 mForceFullLayout = false; 962 int firstVisibleIndex = focusViewWasInTree ? mGrid.getFirstVisibleIndex() : 0; 963 964 if (mGrid == null || mNumRows != mGrid.getNumRows() || 965 mReverseFlowPrimary != mGrid.isReversedFlow()) { 966 mGrid = Grid.createStaggeredMultipleRows(mNumRows); 967 mGrid.setProvider(mGridProvider); 968 mGrid.setReversedFlow(mReverseFlowPrimary); 969 } 970 initScrollController(); 971 updateScrollSecondAxis(); 972 mGrid.setMargin(mMarginPrimary); 973 detachAndScrapAttachedViews(mRecycler); 974 mGrid.resetVisibleIndex(); 975 if (mFocusPosition == NO_POSITION) { 976 mBaseGridView.clearFocus(); 977 } 978 mWindowAlignment.mainAxis().invalidateScrollMin(); 979 mWindowAlignment.mainAxis().invalidateScrollMax(); 980 if (focusViewWasInTree && firstVisibleIndex <= mFocusPosition) { 981 // if focusView was in tree, we will add item from first visible item 982 mGrid.setStart(firstVisibleIndex); 983 } else { 984 // if focusView was not in tree, it's probably because focus position jumped 985 // far away from visible range, so use mFocusPosition as start 986 mGrid.setStart(mFocusPosition); 987 } 988 return false; 989 } 990 } 991 992 private int getRowSizeSecondary(int rowIndex) { 993 if (mFixedRowSizeSecondary != 0) { 994 return mFixedRowSizeSecondary; 995 } 996 if (mRowSizeSecondary == null) { 997 return 0; 998 } 999 return mRowSizeSecondary[rowIndex]; 1000 } 1001 1002 private int getRowStartSecondary(int rowIndex) { 1003 int start = 0; 1004 // Iterate from left to right, which is a different index traversal 1005 // in RTL flow 1006 if (mReverseFlowSecondary) { 1007 for (int i = mNumRows-1; i > rowIndex; i--) { 1008 start += getRowSizeSecondary(i) + mMarginSecondary; 1009 } 1010 } else { 1011 for (int i = 0; i < rowIndex; i++) { 1012 start += getRowSizeSecondary(i) + mMarginSecondary; 1013 } 1014 } 1015 return start; 1016 } 1017 1018 private int getSizeSecondary() { 1019 int rightmostIndex = mReverseFlowSecondary ? 0 : mNumRows - 1; 1020 return getRowStartSecondary(rightmostIndex) + getRowSizeSecondary(rightmostIndex); 1021 } 1022 1023 private void measureScrapChild(int position, int widthSpec, int heightSpec, 1024 int[] measuredDimension) { 1025 View view = mRecycler.getViewForPosition(position); 1026 if (view != null) { 1027 LayoutParams p = (LayoutParams) view.getLayoutParams(); 1028 int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, 1029 getPaddingLeft() + getPaddingRight(), p.width); 1030 int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, 1031 getPaddingTop() + getPaddingBottom(), p.height); 1032 view.measure(childWidthSpec, childHeightSpec); 1033 measuredDimension[0] = view.getMeasuredWidth(); 1034 measuredDimension[1] = view.getMeasuredHeight(); 1035 mRecycler.recycleView(view); 1036 } 1037 } 1038 1039 private boolean processRowSizeSecondary(boolean measure) { 1040 if (mFixedRowSizeSecondary != 0 || mRowSizeSecondary == null) { 1041 return false; 1042 } 1043 1044 if (TRACE) TraceHelper.beginSection("processRowSizeSecondary"); 1045 CircularIntArray[] rows = mGrid == null ? null : mGrid.getItemPositionsInRows(); 1046 boolean changed = false; 1047 int scrapChildWidth = -1; 1048 int scrapChildHeight = -1; 1049 1050 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 1051 CircularIntArray row = rows == null ? null : rows[rowIndex]; 1052 final int rowItemsPairCount = row == null ? 0 : row.size(); 1053 int rowSize = -1; 1054 for (int rowItemPairIndex = 0; rowItemPairIndex < rowItemsPairCount; 1055 rowItemPairIndex += 2) { 1056 final int rowIndexStart = row.get(rowItemPairIndex); 1057 final int rowIndexEnd = row.get(rowItemPairIndex + 1); 1058 for (int i = rowIndexStart; i <= rowIndexEnd; i++) { 1059 final View view = findViewByPosition(i); 1060 if (view == null) { 1061 continue; 1062 } 1063 if (measure && view.isLayoutRequested()) { 1064 measureChild(view); 1065 } 1066 final int secondarySize = mOrientation == HORIZONTAL ? 1067 view.getMeasuredHeight() : view.getMeasuredWidth(); 1068 if (secondarySize > rowSize) { 1069 rowSize = secondarySize; 1070 } 1071 } 1072 } 1073 1074 final int itemCount = mState.getItemCount(); 1075 if (measure && rowSize < 0 && itemCount > 0) { 1076 if (scrapChildWidth < 0 && scrapChildHeight < 0) { 1077 int position; 1078 if (mFocusPosition == NO_POSITION) { 1079 position = 0; 1080 } else if (mFocusPosition >= itemCount) { 1081 position = itemCount - 1; 1082 } else { 1083 position = mFocusPosition; 1084 } 1085 measureScrapChild(position, 1086 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1087 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1088 mMeasuredDimension); 1089 scrapChildWidth = mMeasuredDimension[0]; 1090 scrapChildHeight = mMeasuredDimension[1]; 1091 if (DEBUG) Log.v(TAG, "measured scrap child: " + scrapChildWidth + 1092 " " + scrapChildHeight); 1093 } 1094 rowSize = mOrientation == HORIZONTAL ? scrapChildHeight : scrapChildWidth; 1095 } 1096 if (rowSize < 0) { 1097 rowSize = 0; 1098 } 1099 if (mRowSizeSecondary[rowIndex] != rowSize) { 1100 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 1101 ", " + rowSize); 1102 mRowSizeSecondary[rowIndex] = rowSize; 1103 changed = true; 1104 } 1105 } 1106 1107 if (TRACE) TraceHelper.endSection(); 1108 return changed; 1109 } 1110 1111 /** 1112 * Checks if we need to update row secondary sizes. 1113 */ 1114 private void updateRowSecondarySizeRefresh() { 1115 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 1116 if (mRowSecondarySizeRefresh) { 1117 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 1118 forceRequestLayout(); 1119 } 1120 } 1121 1122 private void forceRequestLayout() { 1123 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 1124 // RecyclerView prevents us from requesting layout in many cases 1125 // (during layout, during scroll, etc.) 1126 // For secondary row size wrap_content support we currently need a 1127 // second layout pass to update the measured size after having measured 1128 // and added child views in layoutChildren. 1129 // Force the second layout by posting a delayed runnable. 1130 // TODO: investigate allowing a second layout pass, 1131 // or move child add/measure logic to the measure phase. 1132 ViewCompat.postOnAnimation(mBaseGridView, mRequestLayoutRunnable); 1133 } 1134 1135 private final Runnable mRequestLayoutRunnable = new Runnable() { 1136 @Override 1137 public void run() { 1138 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 1139 requestLayout(); 1140 } 1141 }; 1142 1143 @Override 1144 public void onMeasure(Recycler recycler, State state, int widthSpec, int heightSpec) { 1145 saveContext(recycler, state); 1146 1147 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 1148 int measuredSizeSecondary; 1149 if (mOrientation == HORIZONTAL) { 1150 sizePrimary = MeasureSpec.getSize(widthSpec); 1151 sizeSecondary = MeasureSpec.getSize(heightSpec); 1152 modeSecondary = MeasureSpec.getMode(heightSpec); 1153 paddingSecondary = getPaddingTop() + getPaddingBottom(); 1154 } else { 1155 sizeSecondary = MeasureSpec.getSize(widthSpec); 1156 sizePrimary = MeasureSpec.getSize(heightSpec); 1157 modeSecondary = MeasureSpec.getMode(widthSpec); 1158 paddingSecondary = getPaddingLeft() + getPaddingRight(); 1159 } 1160 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 1161 " heightSpec " + Integer.toHexString(heightSpec) + 1162 " modeSecondary " + Integer.toHexString(modeSecondary) + 1163 " sizeSecondary " + sizeSecondary + " " + this); 1164 1165 mMaxSizeSecondary = sizeSecondary; 1166 1167 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 1168 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1169 mFixedRowSizeSecondary = 0; 1170 1171 if (mRowSizeSecondary == null || mRowSizeSecondary.length != mNumRows) { 1172 mRowSizeSecondary = new int[mNumRows]; 1173 } 1174 1175 // Measure all current children and update cached row heights 1176 processRowSizeSecondary(true); 1177 1178 switch (modeSecondary) { 1179 case MeasureSpec.UNSPECIFIED: 1180 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 1181 break; 1182 case MeasureSpec.AT_MOST: 1183 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 1184 mMaxSizeSecondary); 1185 break; 1186 case MeasureSpec.EXACTLY: 1187 measuredSizeSecondary = mMaxSizeSecondary; 1188 break; 1189 default: 1190 throw new IllegalStateException("wrong spec"); 1191 } 1192 1193 } else { 1194 switch (modeSecondary) { 1195 case MeasureSpec.UNSPECIFIED: 1196 if (mRowSizeSecondaryRequested == 0) { 1197 if (mOrientation == HORIZONTAL) { 1198 throw new IllegalStateException("Must specify rowHeight or view height"); 1199 } else { 1200 throw new IllegalStateException("Must specify columnWidth or view width"); 1201 } 1202 } 1203 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1204 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1205 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1206 * (mNumRows - 1) + paddingSecondary; 1207 break; 1208 case MeasureSpec.AT_MOST: 1209 case MeasureSpec.EXACTLY: 1210 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 1211 mNumRows = 1; 1212 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 1213 } else if (mNumRowsRequested == 0) { 1214 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1215 mNumRows = (sizeSecondary + mMarginSecondary) 1216 / (mRowSizeSecondaryRequested + mMarginSecondary); 1217 } else if (mRowSizeSecondaryRequested == 0) { 1218 mNumRows = mNumRowsRequested; 1219 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 1220 * (mNumRows - 1)) / mNumRows; 1221 } else { 1222 mNumRows = mNumRowsRequested; 1223 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1224 } 1225 measuredSizeSecondary = sizeSecondary; 1226 if (modeSecondary == MeasureSpec.AT_MOST) { 1227 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1228 * (mNumRows - 1) + paddingSecondary; 1229 if (childrenSize < measuredSizeSecondary) { 1230 measuredSizeSecondary = childrenSize; 1231 } 1232 } 1233 break; 1234 default: 1235 throw new IllegalStateException("wrong spec"); 1236 } 1237 } 1238 if (mOrientation == HORIZONTAL) { 1239 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1240 } else { 1241 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1242 } 1243 if (DEBUG) { 1244 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1245 " measuredSizeSecondary " + measuredSizeSecondary + 1246 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1247 " mNumRows " + mNumRows); 1248 } 1249 leaveContext(); 1250 } 1251 1252 private void measureChild(View child) { 1253 if (TRACE) TraceHelper.beginSection("measureChild"); 1254 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1255 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1256 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1257 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1258 int widthSpec, heightSpec; 1259 1260 if (mOrientation == HORIZONTAL) { 1261 widthSpec = ViewGroup.getChildMeasureSpec( 1262 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1263 0, lp.width); 1264 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1265 } else { 1266 heightSpec = ViewGroup.getChildMeasureSpec( 1267 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1268 0, lp.height); 1269 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1270 } 1271 child.measure(widthSpec, heightSpec); 1272 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1273 " widthSpec " + Integer.toHexString(widthSpec) + 1274 " heightSpec " + Integer.toHexString(heightSpec) + 1275 " measuredWidth " + child.getMeasuredWidth() + 1276 " measuredHeight " + child.getMeasuredHeight()); 1277 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1278 if (TRACE) TraceHelper.endSection(); 1279 } 1280 1281 private Grid.Provider mGridProvider = new Grid.Provider() { 1282 1283 @Override 1284 public int getCount() { 1285 return mState.getItemCount(); 1286 } 1287 1288 @Override 1289 public int createItem(int index, boolean append, Object[] item) { 1290 if (TRACE) TraceHelper.beginSection("createItem"); 1291 if (TRACE) TraceHelper.beginSection("getview"); 1292 View v = getViewForPosition(index); 1293 if (TRACE) TraceHelper.endSection(); 1294 // See recyclerView docs: we don't need re-add scraped view if it was removed. 1295 if (!((RecyclerView.LayoutParams) v.getLayoutParams()).isItemRemoved()) { 1296 if (TRACE) TraceHelper.beginSection("addView"); 1297 if (append) { 1298 addView(v); 1299 } else { 1300 addView(v, 0); 1301 } 1302 if (TRACE) TraceHelper.endSection(); 1303 if (mChildVisibility != -1) { 1304 v.setVisibility(mChildVisibility); 1305 } 1306 1307 if (mPendingMoveSmoothScroller != null) { 1308 mPendingMoveSmoothScroller.consumePendingMovesBeforeLayout(); 1309 } 1310 if (!mInLayout) { 1311 // when we are appending item during scroll pass and the item's position 1312 // matches the mFocusPosition, we should signal a childSelected event. 1313 // However if we are still running PendingMoveSmoothScroller, we defer and 1314 // signal the event in PendingMoveSmoothScroller.onStop(). This can 1315 // avoid lots of childSelected events during a long smooth scrolling and 1316 // increase performance. 1317 if (index == mFocusPosition && (mPendingMoveSmoothScroller == null 1318 || mPendingMoveSmoothScroller.mPendingMoves == 0)) { 1319 dispatchChildSelected(); 1320 } 1321 } else if (!mInFastRelayout) { 1322 // fastRelayout will dispatch event at end of onLayoutChildren(). 1323 // For full layout, two situations here: 1324 // 1. mInLayoutSearchFocus is false, dispatchChildSelected() at mFocusPosition. 1325 // 2. mInLayoutSearchFocus is true: dispatchChildSelected() on first child 1326 // equal to or after mFocusPosition that can take focus. 1327 if (!mInLayoutSearchFocus && index == mFocusPosition) { 1328 dispatchChildSelected(); 1329 } else if (mInLayoutSearchFocus && index >= mFocusPosition 1330 && v.hasFocusable()) { 1331 mFocusPosition = index; 1332 mInLayoutSearchFocus = false; 1333 dispatchChildSelected(); 1334 } 1335 } 1336 measureChild(v); 1337 } 1338 item[0] = v; 1339 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1340 } 1341 1342 @Override 1343 public void addItem(Object item, int index, int length, int rowIndex, int edge) { 1344 View v = (View) item; 1345 int start, end; 1346 if (edge == Integer.MIN_VALUE || edge == Integer.MAX_VALUE) { 1347 edge = !mGrid.isReversedFlow() ? mWindowAlignment.mainAxis().getPaddingLow() 1348 : mWindowAlignment.mainAxis().getSize() 1349 - mWindowAlignment.mainAxis().getPaddingHigh(); 1350 } 1351 boolean edgeIsMin = !mGrid.isReversedFlow(); 1352 if (edgeIsMin) { 1353 start = edge; 1354 end = edge + length; 1355 } else { 1356 start = edge - length; 1357 end = edge; 1358 } 1359 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1360 mChildrenStates.loadView(v, index); 1361 layoutChild(rowIndex, v, start, end, startSecondary); 1362 if (DEBUG) { 1363 Log.d(getTag(), "addView " + index + " " + v); 1364 } 1365 if (TRACE) TraceHelper.endSection(); 1366 1367 if (index == mGrid.getFirstVisibleIndex()) { 1368 if (!mGrid.isReversedFlow()) { 1369 updateScrollMin(); 1370 } else { 1371 updateScrollMax(); 1372 } 1373 } 1374 if (index == mGrid.getLastVisibleIndex()) { 1375 if (!mGrid.isReversedFlow()) { 1376 updateScrollMax(); 1377 } else { 1378 updateScrollMin(); 1379 } 1380 } 1381 if (!mInLayout && mPendingMoveSmoothScroller != null) { 1382 mPendingMoveSmoothScroller.consumePendingMovesAfterLayout(); 1383 } 1384 if (mChildLaidOutListener != null) { 1385 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(v); 1386 mChildLaidOutListener.onChildLaidOut(mBaseGridView, v, index, 1387 vh == null ? NO_ID : vh.getItemId()); 1388 } 1389 } 1390 1391 @Override 1392 public void removeItem(int index) { 1393 if (TRACE) TraceHelper.beginSection("removeItem"); 1394 View v = findViewByPosition(index); 1395 if (mInLayout) { 1396 detachAndScrapView(v, mRecycler); 1397 } else { 1398 removeAndRecycleView(v, mRecycler); 1399 } 1400 if (TRACE) TraceHelper.endSection(); 1401 } 1402 1403 @Override 1404 public int getEdge(int index) { 1405 if (mReverseFlowPrimary) { 1406 return getViewMax(findViewByPosition(index)); 1407 } else { 1408 return getViewMin(findViewByPosition(index)); 1409 } 1410 } 1411 1412 @Override 1413 public int getSize(int index) { 1414 return getViewPrimarySize(findViewByPosition(index)); 1415 } 1416 }; 1417 1418 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1419 if (TRACE) TraceHelper.beginSection("layoutChild"); 1420 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1421 : v.getMeasuredWidth(); 1422 if (mFixedRowSizeSecondary > 0) { 1423 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1424 } 1425 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1426 final int horizontalGravity = (mReverseFlowPrimary || mReverseFlowSecondary) ? 1427 Gravity.getAbsoluteGravity(mGravity & Gravity.RELATIVE_HORIZONTAL_GRAVITY_MASK, View.LAYOUT_DIRECTION_RTL) : 1428 mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1429 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1430 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1431 // do nothing 1432 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1433 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1434 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1435 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1436 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1437 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1438 } 1439 int left, top, right, bottom; 1440 if (mOrientation == HORIZONTAL) { 1441 left = start; 1442 top = startSecondary; 1443 right = end; 1444 bottom = startSecondary + sizeSecondary; 1445 } else { 1446 top = start; 1447 left = startSecondary; 1448 bottom = end; 1449 right = startSecondary + sizeSecondary; 1450 } 1451 v.layout(left, top, right, bottom); 1452 updateChildOpticalInsets(v, left, top, right, bottom); 1453 updateChildAlignments(v); 1454 if (TRACE) TraceHelper.endSection(); 1455 } 1456 1457 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1458 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1459 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1460 v.getRight() - right, v.getBottom() - bottom); 1461 } 1462 1463 private void updateChildAlignments(View v) { 1464 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1465 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1466 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1467 } 1468 1469 private void updateChildAlignments() { 1470 for (int i = 0, c = getChildCount(); i < c; i++) { 1471 updateChildAlignments(getChildAt(i)); 1472 } 1473 } 1474 1475 private void removeInvisibleViewsAtEnd() { 1476 if (mPruneChild) { 1477 mGrid.removeInvisibleItemsAtEnd(mFocusPosition, 1478 mReverseFlowPrimary ? 0 : mSizePrimary); 1479 } 1480 } 1481 1482 private void removeInvisibleViewsAtFront() { 1483 if (mPruneChild) { 1484 mGrid.removeInvisibleItemsAtFront(mFocusPosition, 1485 mReverseFlowPrimary ? mSizePrimary : 0); 1486 } 1487 } 1488 1489 private boolean appendOneColumnVisibleItems() { 1490 return mGrid.appendOneColumnVisibleItems(); 1491 } 1492 1493 private boolean prependOneColumnVisibleItems() { 1494 return mGrid.prependOneColumnVisibleItems(); 1495 } 1496 1497 private void appendVisibleItems() { 1498 mGrid.appendVisibleItems(mReverseFlowPrimary ? 0 : mSizePrimary); 1499 } 1500 1501 private void prependVisibleItems() { 1502 mGrid.prependVisibleItems(mReverseFlowPrimary ? mSizePrimary : 0); 1503 } 1504 1505 /** 1506 * Fast layout when there is no structure change, adapter change, etc. 1507 * It will layout all views was layout requested or updated, until hit a view 1508 * with different size, then it break and detachAndScrap all views after that. 1509 */ 1510 private void fastRelayout() { 1511 boolean invalidateAfter = false; 1512 final int childCount = getChildCount(); 1513 int position = -1; 1514 for (int index = 0; index < childCount; index++) { 1515 View view = getChildAt(index); 1516 position = getPositionByIndex(index); 1517 Grid.Location location = mGrid.getLocation(position); 1518 if (location == null) { 1519 if (DEBUG) Log.w(getTag(), "fastRelayout(): no Location at " + position); 1520 invalidateAfter = true; 1521 break; 1522 } 1523 1524 int startSecondary = getRowStartSecondary(location.row) - mScrollOffsetSecondary; 1525 int primarySize, end; 1526 int start = getViewMin(view); 1527 int oldPrimarySize = getViewPrimarySize(view); 1528 1529 LayoutParams lp = (LayoutParams) view.getLayoutParams(); 1530 if (lp.viewNeedsUpdate()) { 1531 int viewIndex = mBaseGridView.indexOfChild(view); 1532 detachAndScrapView(view, mRecycler); 1533 view = getViewForPosition(position); 1534 addView(view, viewIndex); 1535 } 1536 1537 if (view.isLayoutRequested()) { 1538 measureChild(view); 1539 } 1540 if (mOrientation == HORIZONTAL) { 1541 primarySize = view.getMeasuredWidth(); 1542 end = start + primarySize; 1543 } else { 1544 primarySize = view.getMeasuredHeight(); 1545 end = start + primarySize; 1546 } 1547 layoutChild(location.row, view, start, end, startSecondary); 1548 if (oldPrimarySize != primarySize) { 1549 // size changed invalidate remaining Locations 1550 if (DEBUG) Log.d(getTag(), "fastRelayout: view size changed at " + position); 1551 invalidateAfter = true; 1552 break; 1553 } 1554 } 1555 if (invalidateAfter) { 1556 final int savedLastPos = mGrid.getLastVisibleIndex(); 1557 mGrid.invalidateItemsAfter(position); 1558 if (mPruneChild) { 1559 // in regular prune child mode, we just append items up to edge limit 1560 appendVisibleItems(); 1561 if (mFocusPosition >= 0 && mFocusPosition <= savedLastPos) { 1562 // make sure add focus view back: the view might be outside edge limit 1563 // when there is delta in onLayoutChildren(). 1564 while (mGrid.getLastVisibleIndex() < mFocusPosition) { 1565 mGrid.appendOneColumnVisibleItems(); 1566 } 1567 } 1568 } else { 1569 // prune disabled(e.g. in RowsFragment transition): append all removed items 1570 while (mGrid.appendOneColumnVisibleItems() 1571 && mGrid.getLastVisibleIndex() < savedLastPos); 1572 } 1573 } 1574 updateScrollMin(); 1575 updateScrollMax(); 1576 updateScrollSecondAxis(); 1577 } 1578 1579 public void removeAndRecycleAllViews(RecyclerView.Recycler recycler) { 1580 if (TRACE) TraceHelper.beginSection("removeAndRecycleAllViews"); 1581 if (DEBUG) Log.v(TAG, "removeAndRecycleAllViews " + getChildCount()); 1582 for (int i = getChildCount() - 1; i >= 0; i--) { 1583 removeAndRecycleViewAt(i, recycler); 1584 } 1585 if (TRACE) TraceHelper.endSection(); 1586 } 1587 1588 // Lays out items based on the current scroll position 1589 @Override 1590 public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) { 1591 if (DEBUG) { 1592 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1593 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1594 + " inPreLayout " + state.isPreLayout() 1595 + " didStructureChange " + state.didStructureChange() 1596 + " mForceFullLayout " + mForceFullLayout); 1597 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1598 } 1599 1600 if (mNumRows == 0) { 1601 // haven't done measure yet 1602 return; 1603 } 1604 final int itemCount = state.getItemCount(); 1605 if (itemCount < 0) { 1606 return; 1607 } 1608 1609 if (!mLayoutEnabled) { 1610 discardLayoutInfo(); 1611 removeAndRecycleAllViews(recycler); 1612 return; 1613 } 1614 mInLayout = true; 1615 1616 final boolean scrollToFocus = !isSmoothScrolling() 1617 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED; 1618 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1619 mFocusPosition = mFocusPosition + mFocusPositionOffset; 1620 mFocusPositionOffset = 0; 1621 } 1622 saveContext(recycler, state); 1623 1624 // Track the old focus view so we can adjust our system scroll position 1625 // so that any scroll animations happening now will remain valid. 1626 // We must use same delta in Pre Layout (if prelayout exists) and second layout. 1627 // So we cache the deltas in PreLayout and use it in second layout. 1628 int delta = 0, deltaSecondary = 0; 1629 if (mFocusPosition != NO_POSITION && scrollToFocus 1630 && mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE) { 1631 // FIXME: we should get the remaining scroll animation offset from RecyclerView 1632 View focusView = findViewByPosition(mFocusPosition); 1633 if (focusView != null) { 1634 delta = mWindowAlignment.mainAxis().getSystemScrollPos(mScrollOffsetPrimary 1635 + getViewCenter(focusView), false, false) - mScrollOffsetPrimary; 1636 deltaSecondary = mWindowAlignment.secondAxis().getSystemScrollPos( 1637 mScrollOffsetSecondary + getViewCenterSecondary(focusView), 1638 false, false) - mScrollOffsetSecondary; 1639 } 1640 } 1641 1642 boolean hadFocus = mBaseGridView.hasFocus(); 1643 int savedFocusPos = mFocusPosition; 1644 if (mInFastRelayout = layoutInit()) { 1645 fastRelayout(); 1646 // appends items till focus position. 1647 if (mFocusPosition != NO_POSITION) { 1648 View focusView = findViewByPosition(mFocusPosition); 1649 if (focusView != null) { 1650 if (scrollToFocus) { 1651 scrollToView(focusView, false); 1652 } 1653 if (hadFocus && !focusView.hasFocus()) { 1654 focusView.requestFocus(); 1655 } 1656 } 1657 } 1658 } else { 1659 mInLayoutSearchFocus = hadFocus; 1660 if (mFocusPosition != NO_POSITION) { 1661 // appends items till focus position. 1662 while (appendOneColumnVisibleItems() 1663 && findViewByPosition(mFocusPosition) == null) ; 1664 } 1665 // multiple rounds: scrollToView of first round may drag first/last child into 1666 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1667 int oldFirstVisible; 1668 int oldLastVisible; 1669 do { 1670 updateScrollMin(); 1671 updateScrollMax(); 1672 oldFirstVisible = mGrid.getFirstVisibleIndex(); 1673 oldLastVisible = mGrid.getLastVisibleIndex(); 1674 View focusView = findViewByPosition(mFocusPosition); 1675 // we need force to initialize the child view's position 1676 scrollToView(focusView, false); 1677 if (focusView != null && hadFocus && !focusView.hasFocus()) { 1678 focusView.requestFocus(); 1679 } 1680 appendVisibleItems(); 1681 prependVisibleItems(); 1682 removeInvisibleViewsAtFront(); 1683 removeInvisibleViewsAtEnd(); 1684 } while (mGrid.getFirstVisibleIndex() != oldFirstVisible || 1685 mGrid.getLastVisibleIndex() != oldLastVisible); 1686 } 1687 1688 if (scrollToFocus) { 1689 scrollDirectionPrimary(-delta); 1690 scrollDirectionSecondary(-deltaSecondary); 1691 } 1692 appendVisibleItems(); 1693 prependVisibleItems(); 1694 removeInvisibleViewsAtFront(); 1695 removeInvisibleViewsAtEnd(); 1696 1697 if (DEBUG) { 1698 StringWriter sw = new StringWriter(); 1699 PrintWriter pw = new PrintWriter(sw); 1700 mGrid.debugPrint(pw); 1701 Log.d(getTag(), sw.toString()); 1702 } 1703 1704 if (mRowSecondarySizeRefresh) { 1705 mRowSecondarySizeRefresh = false; 1706 } else { 1707 updateRowSecondarySizeRefresh(); 1708 } 1709 1710 // For fastRelayout, only dispatch event when focus position changes. 1711 if (mInFastRelayout && mFocusPosition != savedFocusPos) { 1712 dispatchChildSelected(); 1713 } else if (!mInFastRelayout && mInLayoutSearchFocus) { 1714 // For full layout we dispatchChildSelected() in createItem() unless searched all 1715 // children and found none is focusable then dispatchChildSelected() here. 1716 dispatchChildSelected(); 1717 } 1718 1719 mInLayout = false; 1720 leaveContext(); 1721 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1722 } 1723 1724 private void offsetChildrenSecondary(int increment) { 1725 final int childCount = getChildCount(); 1726 if (mOrientation == HORIZONTAL) { 1727 for (int i = 0; i < childCount; i++) { 1728 getChildAt(i).offsetTopAndBottom(increment); 1729 } 1730 } else { 1731 for (int i = 0; i < childCount; i++) { 1732 getChildAt(i).offsetLeftAndRight(increment); 1733 } 1734 } 1735 } 1736 1737 private void offsetChildrenPrimary(int increment) { 1738 final int childCount = getChildCount(); 1739 if (mOrientation == VERTICAL) { 1740 for (int i = 0; i < childCount; i++) { 1741 getChildAt(i).offsetTopAndBottom(increment); 1742 } 1743 } else { 1744 for (int i = 0; i < childCount; i++) { 1745 getChildAt(i).offsetLeftAndRight(increment); 1746 } 1747 } 1748 } 1749 1750 @Override 1751 public int scrollHorizontallyBy(int dx, Recycler recycler, RecyclerView.State state) { 1752 if (DEBUG) Log.v(getTag(), "scrollHorizontallyBy " + dx); 1753 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1754 return 0; 1755 } 1756 saveContext(recycler, state); 1757 mInScroll = true; 1758 int result; 1759 if (mOrientation == HORIZONTAL) { 1760 result = scrollDirectionPrimary(dx); 1761 } else { 1762 result = scrollDirectionSecondary(dx); 1763 } 1764 leaveContext(); 1765 mInScroll = false; 1766 return result; 1767 } 1768 1769 @Override 1770 public int scrollVerticallyBy(int dy, Recycler recycler, RecyclerView.State state) { 1771 if (DEBUG) Log.v(getTag(), "scrollVerticallyBy " + dy); 1772 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1773 return 0; 1774 } 1775 mInScroll = true; 1776 saveContext(recycler, state); 1777 int result; 1778 if (mOrientation == VERTICAL) { 1779 result = scrollDirectionPrimary(dy); 1780 } else { 1781 result = scrollDirectionSecondary(dy); 1782 } 1783 leaveContext(); 1784 mInScroll = false; 1785 return result; 1786 } 1787 1788 // scroll in main direction may add/prune views 1789 private int scrollDirectionPrimary(int da) { 1790 if (TRACE) TraceHelper.beginSection("scrollPrimary"); 1791 boolean isMaxUnknown = false, isMinUnknown = false; 1792 int minScroll = 0, maxScroll = 0; 1793 if (da > 0) { 1794 isMaxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1795 if (!isMaxUnknown) { 1796 maxScroll = mWindowAlignment.mainAxis().getMaxScroll(); 1797 if (mScrollOffsetPrimary + da > maxScroll) { 1798 da = maxScroll - mScrollOffsetPrimary; 1799 } 1800 } 1801 } else if (da < 0) { 1802 isMinUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1803 if (!isMinUnknown) { 1804 minScroll = mWindowAlignment.mainAxis().getMinScroll(); 1805 if (mScrollOffsetPrimary + da < minScroll) { 1806 da = minScroll - mScrollOffsetPrimary; 1807 } 1808 } 1809 } 1810 if (da == 0) { 1811 if (TRACE) TraceHelper.endSection(); 1812 return 0; 1813 } 1814 offsetChildrenPrimary(-da); 1815 mScrollOffsetPrimary += da; 1816 if (mInLayout) { 1817 if (TRACE) TraceHelper.endSection(); 1818 return da; 1819 } 1820 1821 int childCount = getChildCount(); 1822 boolean updated; 1823 1824 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1825 prependVisibleItems(); 1826 } else { 1827 appendVisibleItems(); 1828 } 1829 updated = getChildCount() > childCount; 1830 childCount = getChildCount(); 1831 1832 if (TRACE) TraceHelper.beginSection("remove"); 1833 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1834 removeInvisibleViewsAtEnd(); 1835 } else { 1836 removeInvisibleViewsAtFront(); 1837 } 1838 if (TRACE) TraceHelper.endSection(); 1839 updated |= getChildCount() < childCount; 1840 if (updated) { 1841 updateRowSecondarySizeRefresh(); 1842 } 1843 1844 mBaseGridView.invalidate(); 1845 if (TRACE) TraceHelper.endSection(); 1846 return da; 1847 } 1848 1849 // scroll in second direction will not add/prune views 1850 private int scrollDirectionSecondary(int dy) { 1851 if (dy == 0) { 1852 return 0; 1853 } 1854 offsetChildrenSecondary(-dy); 1855 mScrollOffsetSecondary += dy; 1856 mBaseGridView.invalidate(); 1857 return dy; 1858 } 1859 1860 private void updateScrollMax() { 1861 int highVisiblePos = (!mReverseFlowPrimary) ? mGrid.getLastVisibleIndex() 1862 : mGrid.getFirstVisibleIndex(); 1863 int highMaxPos = (!mReverseFlowPrimary) ? mState.getItemCount() - 1 : 0; 1864 if (highVisiblePos < 0) { 1865 return; 1866 } 1867 final boolean highAvailable = highVisiblePos == highMaxPos; 1868 final boolean maxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1869 if (!highAvailable && maxUnknown) { 1870 return; 1871 } 1872 int maxEdge = mGrid.findRowMax(true, sTwoInts) + mScrollOffsetPrimary; 1873 int rowIndex = sTwoInts[0]; 1874 int pos = sTwoInts[1]; 1875 int savedMaxEdge = mWindowAlignment.mainAxis().getMaxEdge(); 1876 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1877 int maxScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1878 mWindowAlignment.mainAxis().setMaxEdge(savedMaxEdge); 1879 1880 if (highAvailable) { 1881 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1882 mWindowAlignment.mainAxis().setMaxScroll(maxScroll); 1883 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge + 1884 " scrollMax to " + maxScroll); 1885 } else { 1886 mWindowAlignment.mainAxis().invalidateScrollMax(); 1887 if (DEBUG) Log.v(getTag(), "Invalidate scrollMax since it should be " 1888 + "greater than " + maxScroll); 1889 } 1890 } 1891 1892 private void updateScrollMin() { 1893 int lowVisiblePos = (!mReverseFlowPrimary) ? mGrid.getFirstVisibleIndex() 1894 : mGrid.getLastVisibleIndex(); 1895 int lowMinPos = (!mReverseFlowPrimary) ? 0 : mState.getItemCount() - 1; 1896 if (lowVisiblePos < 0) { 1897 return; 1898 } 1899 final boolean lowAvailable = lowVisiblePos == lowMinPos; 1900 final boolean minUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1901 if (!lowAvailable && minUnknown) { 1902 return; 1903 } 1904 int minEdge = mGrid.findRowMin(false, sTwoInts) + mScrollOffsetPrimary; 1905 int rowIndex = sTwoInts[0]; 1906 int pos = sTwoInts[1]; 1907 int savedMinEdge = mWindowAlignment.mainAxis().getMinEdge(); 1908 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1909 int minScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1910 mWindowAlignment.mainAxis().setMinEdge(savedMinEdge); 1911 1912 if (lowAvailable) { 1913 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1914 mWindowAlignment.mainAxis().setMinScroll(minScroll); 1915 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge + 1916 " scrollMin to " + minScroll); 1917 } else { 1918 mWindowAlignment.mainAxis().invalidateScrollMin(); 1919 if (DEBUG) Log.v(getTag(), "Invalidate scrollMin, since it should be " 1920 + "less than " + minScroll); 1921 } 1922 } 1923 1924 private void updateScrollSecondAxis() { 1925 mWindowAlignment.secondAxis().setMinEdge(0); 1926 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1927 } 1928 1929 private void initScrollController() { 1930 mWindowAlignment.reset(); 1931 mWindowAlignment.horizontal.setSize(getWidth()); 1932 mWindowAlignment.vertical.setSize(getHeight()); 1933 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1934 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1935 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1936 mScrollOffsetPrimary = -mWindowAlignment.mainAxis().getPaddingLow(); 1937 mScrollOffsetSecondary = -mWindowAlignment.secondAxis().getPaddingLow(); 1938 1939 if (DEBUG) { 1940 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1941 + " mWindowAlignment " + mWindowAlignment 1942 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1943 } 1944 } 1945 1946 private void updateScrollController() { 1947 // mScrollOffsetPrimary and mScrollOffsetSecondary includes the padding. 1948 // e.g. when topPadding is 16 for horizontal grid view, the initial 1949 // mScrollOffsetSecondary is -16. fastRelayout() put views based on offsets(not padding), 1950 // when padding changes to 20, we also need update mScrollOffsetSecondary to -20 before 1951 // fastRelayout() is performed 1952 int paddingPrimaryDiff, paddingSecondaryDiff; 1953 if (mOrientation == HORIZONTAL) { 1954 paddingPrimaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1955 paddingSecondaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1956 } else { 1957 paddingPrimaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1958 paddingSecondaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1959 } 1960 mScrollOffsetPrimary -= paddingPrimaryDiff; 1961 mScrollOffsetSecondary -= paddingSecondaryDiff; 1962 1963 mWindowAlignment.horizontal.setSize(getWidth()); 1964 mWindowAlignment.vertical.setSize(getHeight()); 1965 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1966 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1967 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1968 1969 if (DEBUG) { 1970 Log.v(getTag(), "updateScrollController mSizePrimary " + mSizePrimary 1971 + " mWindowAlignment " + mWindowAlignment 1972 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1973 } 1974 } 1975 1976 public void setSelection(RecyclerView parent, int position, 1977 int primaryScrollExtra) { 1978 setSelection(parent, position, false, primaryScrollExtra); 1979 } 1980 1981 public void setSelectionSmooth(RecyclerView parent, int position) { 1982 setSelection(parent, position, true, 0); 1983 } 1984 1985 public int getSelection() { 1986 return mFocusPosition; 1987 } 1988 1989 public void setSelection(RecyclerView parent, int position, boolean smooth, 1990 int primaryScrollExtra) { 1991 if (mFocusPosition != position && position != NO_POSITION 1992 || primaryScrollExtra != mPrimaryScrollExtra) { 1993 scrollToSelection(parent, position, smooth, primaryScrollExtra); 1994 } 1995 } 1996 1997 private void scrollToSelection(RecyclerView parent, int position, boolean smooth, 1998 int primaryScrollExtra) { 1999 if (TRACE) TraceHelper.beginSection("scrollToSelection"); 2000 mPrimaryScrollExtra = primaryScrollExtra; 2001 View view = findViewByPosition(position); 2002 if (view != null) { 2003 mInSelection = true; 2004 scrollToView(view, smooth); 2005 mInSelection = false; 2006 } else { 2007 mFocusPosition = position; 2008 mFocusPositionOffset = 0; 2009 if (!mLayoutEnabled) { 2010 return; 2011 } 2012 if (smooth) { 2013 if (!hasDoneFirstLayout()) { 2014 Log.w(getTag(), "setSelectionSmooth should " + 2015 "not be called before first layout pass"); 2016 return; 2017 } 2018 startPositionSmoothScroller(position); 2019 } else { 2020 mForceFullLayout = true; 2021 parent.requestLayout(); 2022 } 2023 } 2024 if (TRACE) TraceHelper.endSection(); 2025 } 2026 2027 void startPositionSmoothScroller(int position) { 2028 LinearSmoothScroller linearSmoothScroller = new GridLinearSmoothScroller() { 2029 @Override 2030 public PointF computeScrollVectorForPosition(int targetPosition) { 2031 if (getChildCount() == 0) { 2032 return null; 2033 } 2034 final int firstChildPos = getPosition(getChildAt(0)); 2035 // TODO We should be able to deduce direction from bounds of current and target 2036 // focus, rather than making assumptions about positions and directionality 2037 final boolean isStart = mReverseFlowPrimary ? targetPosition > firstChildPos 2038 : targetPosition < firstChildPos; 2039 final int direction = isStart ? -1 : 1; 2040 if (mOrientation == HORIZONTAL) { 2041 return new PointF(direction, 0); 2042 } else { 2043 return new PointF(0, direction); 2044 } 2045 } 2046 2047 }; 2048 linearSmoothScroller.setTargetPosition(position); 2049 startSmoothScroll(linearSmoothScroller); 2050 } 2051 2052 private void processPendingMovement(boolean forward) { 2053 if (forward ? hasCreatedLastItem() : hasCreatedFirstItem()) { 2054 return; 2055 } 2056 if (mPendingMoveSmoothScroller == null) { 2057 // Stop existing scroller and create a new PendingMoveSmoothScroller. 2058 mBaseGridView.stopScroll(); 2059 PendingMoveSmoothScroller linearSmoothScroller = new PendingMoveSmoothScroller( 2060 forward ? 1 : -1, mNumRows > 1); 2061 mFocusPositionOffset = 0; 2062 startSmoothScroll(linearSmoothScroller); 2063 if (linearSmoothScroller.isRunning()) { 2064 mPendingMoveSmoothScroller = linearSmoothScroller; 2065 } 2066 } else { 2067 if (forward) { 2068 mPendingMoveSmoothScroller.increasePendingMoves(); 2069 } else { 2070 mPendingMoveSmoothScroller.decreasePendingMoves(); 2071 } 2072 } 2073 } 2074 2075 @Override 2076 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 2077 if (DEBUG) Log.v(getTag(), "onItemsAdded positionStart " 2078 + positionStart + " itemCount " + itemCount); 2079 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2080 int pos = mFocusPosition + mFocusPositionOffset; 2081 if (positionStart <= pos) { 2082 mFocusPositionOffset += itemCount; 2083 } 2084 } 2085 mChildrenStates.clear(); 2086 } 2087 2088 @Override 2089 public void onItemsChanged(RecyclerView recyclerView) { 2090 if (DEBUG) Log.v(getTag(), "onItemsChanged"); 2091 mFocusPositionOffset = 0; 2092 mChildrenStates.clear(); 2093 } 2094 2095 @Override 2096 public void onItemsRemoved(RecyclerView recyclerView, int positionStart, int itemCount) { 2097 if (DEBUG) Log.v(getTag(), "onItemsRemoved positionStart " 2098 + positionStart + " itemCount " + itemCount); 2099 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2100 int pos = mFocusPosition + mFocusPositionOffset; 2101 if (positionStart <= pos) { 2102 if (positionStart + itemCount > pos) { 2103 // stop updating offset after the focus item was removed 2104 mFocusPositionOffset = Integer.MIN_VALUE; 2105 } else { 2106 mFocusPositionOffset -= itemCount; 2107 } 2108 } 2109 } 2110 mChildrenStates.clear(); 2111 } 2112 2113 @Override 2114 public void onItemsMoved(RecyclerView recyclerView, int fromPosition, int toPosition, 2115 int itemCount) { 2116 if (DEBUG) Log.v(getTag(), "onItemsMoved fromPosition " 2117 + fromPosition + " toPosition " + toPosition); 2118 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2119 int pos = mFocusPosition + mFocusPositionOffset; 2120 if (fromPosition <= pos && pos < fromPosition + itemCount) { 2121 // moved items include focused position 2122 mFocusPositionOffset += toPosition - fromPosition; 2123 } else if (fromPosition < pos && toPosition > pos - itemCount) { 2124 // move items before focus position to after focused position 2125 mFocusPositionOffset -= itemCount; 2126 } else if (fromPosition > pos && toPosition < pos) { 2127 // move items after focus position to before focused position 2128 mFocusPositionOffset += itemCount; 2129 } 2130 } 2131 mChildrenStates.clear(); 2132 } 2133 2134 @Override 2135 public void onItemsUpdated(RecyclerView recyclerView, int positionStart, int itemCount) { 2136 if (DEBUG) Log.v(getTag(), "onItemsUpdated positionStart " 2137 + positionStart + " itemCount " + itemCount); 2138 for (int i = positionStart, end = positionStart + itemCount; i < end; i++) { 2139 mChildrenStates.remove(i); 2140 } 2141 } 2142 2143 @Override 2144 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 2145 if (mFocusSearchDisabled) { 2146 return true; 2147 } 2148 if (getPositionByView(child) == NO_POSITION) { 2149 // This shouldn't happen, but in case it does be sure not to attempt a 2150 // scroll to a view whose item has been removed. 2151 return true; 2152 } 2153 if (!mInLayout && !mInSelection && !mInScroll) { 2154 scrollToView(child, true); 2155 } 2156 return true; 2157 } 2158 2159 @Override 2160 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 2161 boolean immediate) { 2162 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 2163 return false; 2164 } 2165 2166 int getScrollOffsetX() { 2167 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 2168 } 2169 2170 int getScrollOffsetY() { 2171 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 2172 } 2173 2174 public void getViewSelectedOffsets(View view, int[] offsets) { 2175 if (mOrientation == HORIZONTAL) { 2176 offsets[0] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2177 offsets[1] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2178 } else { 2179 offsets[1] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2180 offsets[0] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2181 } 2182 } 2183 2184 private int getPrimarySystemScrollPosition(View view) { 2185 final int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 2186 final int viewMin = getViewMin(view); 2187 final int viewMax = getViewMax(view); 2188 // TODO: change to use State object in onRequestChildFocus() 2189 boolean isMin, isMax; 2190 if (!mReverseFlowPrimary) { 2191 isMin = mGrid.getFirstVisibleIndex() == 0; 2192 isMax = mGrid.getLastVisibleIndex() == (mState == null ? 2193 getItemCount() : mState.getItemCount()) - 1; 2194 } else { 2195 isMax = mGrid.getFirstVisibleIndex() == 0; 2196 isMin = mGrid.getLastVisibleIndex() == (mState == null ? 2197 getItemCount() : mState.getItemCount()) - 1; 2198 } 2199 for (int i = getChildCount() - 1; (isMin || isMax) && i >= 0; i--) { 2200 View v = getChildAt(i); 2201 if (v == view || v == null) { 2202 continue; 2203 } 2204 if (isMin && getViewMin(v) < viewMin) { 2205 isMin = false; 2206 } 2207 if (isMax && getViewMax(v) > viewMax) { 2208 isMax = false; 2209 } 2210 } 2211 return mWindowAlignment.mainAxis().getSystemScrollPos(viewCenterPrimary, isMin, isMax); 2212 } 2213 2214 private int getSecondarySystemScrollPosition(View view) { 2215 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 2216 int pos = getPositionByView(view); 2217 Grid.Location location = mGrid.getLocation(pos); 2218 final int row = location.row; 2219 final boolean isMin, isMax; 2220 if (!mReverseFlowSecondary) { 2221 isMin = row == 0; 2222 isMax = row == mGrid.getNumRows() - 1; 2223 } else { 2224 isMax = row == 0; 2225 isMin = row == mGrid.getNumRows() - 1; 2226 } 2227 return mWindowAlignment.secondAxis().getSystemScrollPos(viewCenterSecondary, isMin, isMax); 2228 } 2229 2230 /** 2231 * Scroll to a given child view and change mFocusPosition. 2232 */ 2233 private void scrollToView(View view, boolean smooth) { 2234 int newFocusPosition = getPositionByView(view); 2235 if (newFocusPosition != mFocusPosition) { 2236 mFocusPosition = newFocusPosition; 2237 mFocusPositionOffset = 0; 2238 if (!mInLayout) { 2239 dispatchChildSelected(); 2240 } 2241 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 2242 mBaseGridView.invalidate(); 2243 } 2244 } 2245 if (view == null) { 2246 return; 2247 } 2248 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 2249 // transfer focus to the child if it does not have focus yet (e.g. triggered 2250 // by setSelection()) 2251 view.requestFocus(); 2252 } 2253 if (!mScrollEnabled && smooth) { 2254 return; 2255 } 2256 if (getScrollPosition(view, sTwoInts)) { 2257 scrollGrid(sTwoInts[0], sTwoInts[1], smooth); 2258 } 2259 } 2260 2261 private boolean getScrollPosition(View view, int[] deltas) { 2262 switch (mFocusScrollStrategy) { 2263 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2264 default: 2265 return getAlignedPosition(view, deltas); 2266 case BaseGridView.FOCUS_SCROLL_ITEM: 2267 case BaseGridView.FOCUS_SCROLL_PAGE: 2268 return getNoneAlignedPosition(view, deltas); 2269 } 2270 } 2271 2272 private boolean getNoneAlignedPosition(View view, int[] deltas) { 2273 int pos = getPositionByView(view); 2274 int viewMin = getViewMin(view); 2275 int viewMax = getViewMax(view); 2276 // we either align "firstView" to left/top padding edge 2277 // or align "lastView" to right/bottom padding edge 2278 View firstView = null; 2279 View lastView = null; 2280 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 2281 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 2282 final int row = mGrid.getRowIndex(pos); 2283 if (viewMin < paddingLow) { 2284 // view enters low padding area: 2285 firstView = view; 2286 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2287 // scroll one "page" left/top, 2288 // align first visible item of the "page" at the low padding edge. 2289 while (prependOneColumnVisibleItems()) { 2290 CircularIntArray positions = 2291 mGrid.getItemPositionsInRows(mGrid.getFirstVisibleIndex(), pos)[row]; 2292 firstView = findViewByPosition(positions.get(0)); 2293 if (viewMax - getViewMin(firstView) > clientSize) { 2294 if (positions.size() > 2) { 2295 firstView = findViewByPosition(positions.get(2)); 2296 } 2297 break; 2298 } 2299 } 2300 } 2301 } else if (viewMax > clientSize + paddingLow) { 2302 // view enters high padding area: 2303 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2304 // scroll whole one page right/bottom, align view at the low padding edge. 2305 firstView = view; 2306 do { 2307 CircularIntArray positions = 2308 mGrid.getItemPositionsInRows(pos, mGrid.getLastVisibleIndex())[row]; 2309 lastView = findViewByPosition(positions.get(positions.size() - 1)); 2310 if (getViewMax(lastView) - viewMin > clientSize) { 2311 lastView = null; 2312 break; 2313 } 2314 } while (appendOneColumnVisibleItems()); 2315 if (lastView != null) { 2316 // however if we reached end, we should align last view. 2317 firstView = null; 2318 } 2319 } else { 2320 lastView = view; 2321 } 2322 } 2323 int scrollPrimary = 0; 2324 int scrollSecondary = 0; 2325 if (firstView != null) { 2326 scrollPrimary = getViewMin(firstView) - paddingLow; 2327 } else if (lastView != null) { 2328 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 2329 } 2330 View secondaryAlignedView; 2331 if (firstView != null) { 2332 secondaryAlignedView = firstView; 2333 } else if (lastView != null) { 2334 secondaryAlignedView = lastView; 2335 } else { 2336 secondaryAlignedView = view; 2337 } 2338 scrollSecondary = getSecondarySystemScrollPosition(secondaryAlignedView); 2339 scrollSecondary -= mScrollOffsetSecondary; 2340 if (scrollPrimary != 0 || scrollSecondary != 0) { 2341 deltas[0] = scrollPrimary; 2342 deltas[1] = scrollSecondary; 2343 return true; 2344 } 2345 return false; 2346 } 2347 2348 private boolean getAlignedPosition(View view, int[] deltas) { 2349 int scrollPrimary = getPrimarySystemScrollPosition(view); 2350 int scrollSecondary = getSecondarySystemScrollPosition(view); 2351 if (DEBUG) { 2352 Log.v(getTag(), "getAlignedPosition " + scrollPrimary + " " + scrollSecondary 2353 + " " + mPrimaryScrollExtra + " " + mWindowAlignment); 2354 Log.v(getTag(), "getAlignedPosition " + mScrollOffsetPrimary + " " + mScrollOffsetSecondary); 2355 } 2356 scrollPrimary -= mScrollOffsetPrimary; 2357 scrollSecondary -= mScrollOffsetSecondary; 2358 scrollPrimary += mPrimaryScrollExtra; 2359 if (scrollPrimary != 0 || scrollSecondary != 0) { 2360 deltas[0] = scrollPrimary; 2361 deltas[1] = scrollSecondary; 2362 return true; 2363 } 2364 return false; 2365 } 2366 2367 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 2368 if (mInLayout) { 2369 scrollDirectionPrimary(scrollPrimary); 2370 scrollDirectionSecondary(scrollSecondary); 2371 } else { 2372 int scrollX; 2373 int scrollY; 2374 if (mOrientation == HORIZONTAL) { 2375 scrollX = scrollPrimary; 2376 scrollY = scrollSecondary; 2377 } else { 2378 scrollX = scrollSecondary; 2379 scrollY = scrollPrimary; 2380 } 2381 if (smooth) { 2382 mBaseGridView.smoothScrollBy(scrollX, scrollY); 2383 } else { 2384 mBaseGridView.scrollBy(scrollX, scrollY); 2385 } 2386 } 2387 } 2388 2389 public void setPruneChild(boolean pruneChild) { 2390 if (mPruneChild != pruneChild) { 2391 mPruneChild = pruneChild; 2392 if (mPruneChild) { 2393 requestLayout(); 2394 } 2395 } 2396 } 2397 2398 public boolean getPruneChild() { 2399 return mPruneChild; 2400 } 2401 2402 public void setScrollEnabled(boolean scrollEnabled) { 2403 if (mScrollEnabled != scrollEnabled) { 2404 mScrollEnabled = scrollEnabled; 2405 if (mScrollEnabled && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED 2406 && mFocusPosition != NO_POSITION) { 2407 scrollToSelection(mBaseGridView, mFocusPosition, true, mPrimaryScrollExtra); 2408 } 2409 } 2410 } 2411 2412 public boolean isScrollEnabled() { 2413 return mScrollEnabled; 2414 } 2415 2416 private int findImmediateChildIndex(View view) { 2417 while (view != null && view != mBaseGridView) { 2418 int index = mBaseGridView.indexOfChild(view); 2419 if (index >= 0) { 2420 return index; 2421 } 2422 view = (View) view.getParent(); 2423 } 2424 return NO_POSITION; 2425 } 2426 2427 void setFocusSearchDisabled(boolean disabled) { 2428 mFocusSearchDisabled = disabled; 2429 } 2430 2431 boolean isFocusSearchDisabled() { 2432 return mFocusSearchDisabled; 2433 } 2434 2435 @Override 2436 public View onInterceptFocusSearch(View focused, int direction) { 2437 if (mFocusSearchDisabled) { 2438 return focused; 2439 } 2440 return null; 2441 } 2442 2443 boolean hasPreviousViewInSameRow(int pos) { 2444 if (mGrid == null || pos == NO_POSITION || mGrid.getFirstVisibleIndex() < 0) { 2445 return false; 2446 } 2447 if (mGrid.getFirstVisibleIndex() > 0) { 2448 return true; 2449 } 2450 final int focusedRow = mGrid.getLocation(pos).row; 2451 for (int i = getChildCount() - 1; i >= 0; i--) { 2452 int position = getPositionByIndex(i); 2453 Grid.Location loc = mGrid.getLocation(position); 2454 if (loc != null && loc.row == focusedRow) { 2455 if (position < pos) { 2456 return true; 2457 } 2458 } 2459 } 2460 return false; 2461 } 2462 2463 @Override 2464 public boolean onAddFocusables(RecyclerView recyclerView, 2465 ArrayList<View> views, int direction, int focusableMode) { 2466 if (mFocusSearchDisabled) { 2467 return true; 2468 } 2469 // If this viewgroup or one of its children currently has focus then we 2470 // consider our children for focus searching in main direction on the same row. 2471 // If this viewgroup has no focus and using focus align, we want the system 2472 // to ignore our children and pass focus to the viewgroup, which will pass 2473 // focus on to its children appropriately. 2474 // If this viewgroup has no focus and not using focus align, we want to 2475 // consider the child that does not overlap with padding area. 2476 if (recyclerView.hasFocus()) { 2477 final int movement = getMovement(direction); 2478 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2479 // Move on secondary direction uses default addFocusables(). 2480 return false; 2481 } 2482 if (mPendingMoveSmoothScroller != null) { 2483 // don't find next focusable if has pending movement. 2484 return true; 2485 } 2486 final View focused = recyclerView.findFocus(); 2487 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2488 // Add focusables of focused item. 2489 if (focusedPos != NO_POSITION) { 2490 findViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2491 } 2492 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2493 mGrid.getLocation(focusedPos).row : NO_POSITION; 2494 // Add focusables of next neighbor of same row on the focus search direction. 2495 if (mGrid != null) { 2496 final int focusableCount = views.size(); 2497 for (int i = 0, count = getChildCount(); i < count; i++) { 2498 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2499 final View child = getChildAt(index); 2500 if (child.getVisibility() != View.VISIBLE || !child.hasFocusable()) { 2501 continue; 2502 } 2503 int position = getPositionByIndex(index); 2504 Grid.Location loc = mGrid.getLocation(position); 2505 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2506 if (focusedPos == NO_POSITION || 2507 (movement == NEXT_ITEM && position > focusedPos) 2508 || (movement == PREV_ITEM && position < focusedPos)) { 2509 child.addFocusables(views, direction, focusableMode); 2510 if (views.size() > focusableCount) { 2511 break; 2512 } 2513 } 2514 } 2515 } 2516 } 2517 } else { 2518 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2519 // adding views not overlapping padding area to avoid scrolling in gaining focus 2520 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2521 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2522 int focusableCount = views.size(); 2523 for (int i = 0, count = getChildCount(); i < count; i++) { 2524 View child = getChildAt(i); 2525 if (child.getVisibility() == View.VISIBLE) { 2526 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2527 child.addFocusables(views, direction, focusableMode); 2528 } 2529 } 2530 } 2531 // if we cannot find any, then just add all children. 2532 if (views.size() == focusableCount) { 2533 for (int i = 0, count = getChildCount(); i < count; i++) { 2534 View child = getChildAt(i); 2535 if (child.getVisibility() == View.VISIBLE) { 2536 child.addFocusables(views, direction, focusableMode); 2537 } 2538 } 2539 if (views.size() != focusableCount) { 2540 return true; 2541 } 2542 } else { 2543 return true; 2544 } 2545 // if still cannot find any, fall through and add itself 2546 } 2547 if (recyclerView.isFocusable()) { 2548 views.add(recyclerView); 2549 } 2550 } 2551 return true; 2552 } 2553 2554 private boolean hasCreatedLastItem() { 2555 int count = mState.getItemCount(); 2556 return count == 0 || findViewByPosition(count - 1) != null; 2557 } 2558 2559 private boolean hasCreatedFirstItem() { 2560 int count = mState.getItemCount(); 2561 return count == 0 || findViewByPosition(0) != null; 2562 } 2563 2564 boolean canScrollTo(View view) { 2565 return view.getVisibility() == View.VISIBLE && (!hasFocus() || view.hasFocusable()); 2566 } 2567 2568 @Override 2569 public View onFocusSearchFailed(View focused, int direction, Recycler recycler, 2570 RecyclerView.State state) { 2571 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2572 2573 View view = null; 2574 int movement = getMovement(direction); 2575 final boolean isScroll = mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE; 2576 saveContext(recycler, state); 2577 if (movement == NEXT_ITEM) { 2578 if (isScroll || !mFocusOutEnd) { 2579 view = focused; 2580 } 2581 if (mScrollEnabled && !hasCreatedLastItem()) { 2582 processPendingMovement(true); 2583 view = focused; 2584 } 2585 } else if (movement == PREV_ITEM) { 2586 if (isScroll || !mFocusOutFront) { 2587 view = focused; 2588 } 2589 if (mScrollEnabled && !hasCreatedFirstItem()) { 2590 processPendingMovement(false); 2591 view = focused; 2592 } 2593 } 2594 leaveContext(); 2595 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed returning view " + view); 2596 return view; 2597 } 2598 2599 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2600 Rect previouslyFocusedRect) { 2601 switch (mFocusScrollStrategy) { 2602 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2603 default: 2604 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2605 direction, previouslyFocusedRect); 2606 case BaseGridView.FOCUS_SCROLL_PAGE: 2607 case BaseGridView.FOCUS_SCROLL_ITEM: 2608 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2609 direction, previouslyFocusedRect); 2610 } 2611 } 2612 2613 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2614 int direction, Rect previouslyFocusedRect) { 2615 View view = findViewByPosition(mFocusPosition); 2616 if (view != null) { 2617 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2618 if (!result && DEBUG) { 2619 Log.w(getTag(), "failed to request focus on " + view); 2620 } 2621 return result; 2622 } 2623 return false; 2624 } 2625 2626 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2627 int direction, Rect previouslyFocusedRect) { 2628 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2629 int index; 2630 int increment; 2631 int end; 2632 int count = getChildCount(); 2633 if ((direction & View.FOCUS_FORWARD) != 0) { 2634 index = 0; 2635 increment = 1; 2636 end = count; 2637 } else { 2638 index = count - 1; 2639 increment = -1; 2640 end = -1; 2641 } 2642 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2643 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2644 for (int i = index; i != end; i += increment) { 2645 View child = getChildAt(i); 2646 if (child.getVisibility() == View.VISIBLE) { 2647 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2648 if (child.requestFocus(direction, previouslyFocusedRect)) { 2649 return true; 2650 } 2651 } 2652 } 2653 } 2654 return false; 2655 } 2656 2657 private final static int PREV_ITEM = 0; 2658 private final static int NEXT_ITEM = 1; 2659 private final static int PREV_ROW = 2; 2660 private final static int NEXT_ROW = 3; 2661 2662 private int getMovement(int direction) { 2663 int movement = View.FOCUS_LEFT; 2664 2665 if (mOrientation == HORIZONTAL) { 2666 switch(direction) { 2667 case View.FOCUS_LEFT: 2668 movement = (!mReverseFlowPrimary) ? PREV_ITEM : NEXT_ITEM; 2669 break; 2670 case View.FOCUS_RIGHT: 2671 movement = (!mReverseFlowPrimary) ? NEXT_ITEM : PREV_ITEM; 2672 break; 2673 case View.FOCUS_UP: 2674 movement = PREV_ROW; 2675 break; 2676 case View.FOCUS_DOWN: 2677 movement = NEXT_ROW; 2678 break; 2679 } 2680 } else if (mOrientation == VERTICAL) { 2681 switch(direction) { 2682 case View.FOCUS_LEFT: 2683 movement = (!mReverseFlowPrimary) ? PREV_ROW : NEXT_ROW; 2684 break; 2685 case View.FOCUS_RIGHT: 2686 movement = (!mReverseFlowPrimary) ? NEXT_ROW : PREV_ROW; 2687 break; 2688 case View.FOCUS_UP: 2689 movement = PREV_ITEM; 2690 break; 2691 case View.FOCUS_DOWN: 2692 movement = NEXT_ITEM; 2693 break; 2694 } 2695 } 2696 2697 return movement; 2698 } 2699 2700 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2701 View view = findViewByPosition(mFocusPosition); 2702 if (view == null) { 2703 return i; 2704 } 2705 int focusIndex = recyclerView.indexOfChild(view); 2706 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2707 // drawing order is 0 1 2 3 9 8 7 6 5 4 2708 if (i < focusIndex) { 2709 return i; 2710 } else if (i < childCount - 1) { 2711 return focusIndex + childCount - 1 - i; 2712 } else { 2713 return focusIndex; 2714 } 2715 } 2716 2717 @Override 2718 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2719 RecyclerView.Adapter newAdapter) { 2720 if (DEBUG) Log.v(getTag(), "onAdapterChanged to " + newAdapter); 2721 if (oldAdapter != null) { 2722 discardLayoutInfo(); 2723 mFocusPosition = NO_POSITION; 2724 mFocusPositionOffset = 0; 2725 mChildrenStates.clear(); 2726 } 2727 super.onAdapterChanged(oldAdapter, newAdapter); 2728 } 2729 2730 private void discardLayoutInfo() { 2731 mGrid = null; 2732 mRowSizeSecondary = null; 2733 mRowSecondarySizeRefresh = false; 2734 } 2735 2736 public void setLayoutEnabled(boolean layoutEnabled) { 2737 if (mLayoutEnabled != layoutEnabled) { 2738 mLayoutEnabled = layoutEnabled; 2739 requestLayout(); 2740 } 2741 } 2742 2743 void setChildrenVisibility(int visiblity) { 2744 mChildVisibility = visiblity; 2745 if (mChildVisibility != -1) { 2746 int count = getChildCount(); 2747 for (int i= 0; i < count; i++) { 2748 getChildAt(i).setVisibility(mChildVisibility); 2749 } 2750 } 2751 } 2752 2753 final static class SavedState implements Parcelable { 2754 2755 int index; // index inside adapter of the current view 2756 Bundle childStates = Bundle.EMPTY; 2757 2758 @Override 2759 public void writeToParcel(Parcel out, int flags) { 2760 out.writeInt(index); 2761 out.writeBundle(childStates); 2762 } 2763 2764 @SuppressWarnings("hiding") 2765 public static final Parcelable.Creator<SavedState> CREATOR = 2766 new Parcelable.Creator<SavedState>() { 2767 @Override 2768 public SavedState createFromParcel(Parcel in) { 2769 return new SavedState(in); 2770 } 2771 2772 @Override 2773 public SavedState[] newArray(int size) { 2774 return new SavedState[size]; 2775 } 2776 }; 2777 2778 @Override 2779 public int describeContents() { 2780 return 0; 2781 } 2782 2783 SavedState(Parcel in) { 2784 index = in.readInt(); 2785 childStates = in.readBundle(GridLayoutManager.class.getClassLoader()); 2786 } 2787 2788 SavedState() { 2789 } 2790 } 2791 2792 @Override 2793 public Parcelable onSaveInstanceState() { 2794 if (DEBUG) Log.v(getTag(), "onSaveInstanceState getSelection() " + getSelection()); 2795 SavedState ss = new SavedState(); 2796 for (int i = 0, count = getChildCount(); i < count; i++) { 2797 View view = getChildAt(i); 2798 int position = getPositionByView(view); 2799 if (position != NO_POSITION) { 2800 mChildrenStates.saveOnScreenView(view, position); 2801 } 2802 } 2803 ss.index = getSelection(); 2804 ss.childStates = mChildrenStates.saveAsBundle(); 2805 return ss; 2806 } 2807 2808 void onChildRecycled(RecyclerView.ViewHolder holder) { 2809 final int position = holder.getAdapterPosition(); 2810 if (position != NO_POSITION) { 2811 mChildrenStates.saveOffscreenView(holder.itemView, position); 2812 } 2813 } 2814 2815 @Override 2816 public void onRestoreInstanceState(Parcelable state) { 2817 if (!(state instanceof SavedState)) { 2818 return; 2819 } 2820 SavedState loadingState = (SavedState)state; 2821 mFocusPosition = loadingState.index; 2822 mFocusPositionOffset = 0; 2823 mChildrenStates.loadFromBundle(loadingState.childStates); 2824 mForceFullLayout = true; 2825 requestLayout(); 2826 if (DEBUG) Log.v(getTag(), "onRestoreInstanceState mFocusPosition " + mFocusPosition); 2827 } 2828} 2829