GridLayoutManager.java revision 7538845719cd1e588185ce9ae60320377862ef8d
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 = false; 422 private boolean mInFastRelayout; 423 /** 424 * During full layout pass, when GridView had focus: onLayoutChildren will 425 * skip non-focusable child and adjust mFocusPosition. 426 */ 427 private boolean mInLayoutSearchFocus; 428 private boolean mInSelection = false; 429 430 private OnChildSelectedListener mChildSelectedListener = null; 431 432 private OnChildLaidOutListener mChildLaidOutListener = null; 433 434 /** 435 * The focused position, it's not the currently visually aligned position 436 * but it is the final position that we intend to focus on. If there are 437 * multiple setSelection() called, mFocusPosition saves last value. 438 */ 439 private int mFocusPosition = NO_POSITION; 440 441 /** 442 * LinearSmoothScroller that consume pending DPAD movements. 443 */ 444 private PendingMoveSmoothScroller mPendingMoveSmoothScroller; 445 446 /** 447 * The offset to be applied to mFocusPosition, due to adapter change, on the next 448 * layout. Set to Integer.MIN_VALUE means item was removed. 449 * TODO: This is somewhat duplication of RecyclerView getOldPosition() which is 450 * unfortunately cleared after prelayout. 451 */ 452 private int mFocusPositionOffset = 0; 453 454 /** 455 * Extra pixels applied on primary direction. 456 */ 457 private int mPrimaryScrollExtra; 458 459 /** 460 * Force a full layout under certain situations. E.g. Rows change, jump to invisible child. 461 */ 462 private boolean mForceFullLayout; 463 464 /** 465 * True if layout is enabled. 466 */ 467 private boolean mLayoutEnabled = true; 468 469 /** 470 * override child visibility 471 */ 472 private int mChildVisibility = -1; 473 474 /** 475 * The scroll offsets of the viewport relative to the entire view. 476 */ 477 private int mScrollOffsetPrimary; 478 private int mScrollOffsetSecondary; 479 480 /** 481 * User-specified row height/column width. Can be WRAP_CONTENT. 482 */ 483 private int mRowSizeSecondaryRequested; 484 485 /** 486 * The fixed size of each grid item in the secondary direction. This corresponds to 487 * the row height, equal for all rows. Grid items may have variable length 488 * in the primary direction. 489 */ 490 private int mFixedRowSizeSecondary; 491 492 /** 493 * Tracks the secondary size of each row. 494 */ 495 private int[] mRowSizeSecondary; 496 497 /** 498 * Flag controlling whether the current/next layout should 499 * be updating the secondary size of rows. 500 */ 501 private boolean mRowSecondarySizeRefresh; 502 503 /** 504 * The maximum measured size of the view. 505 */ 506 private int mMaxSizeSecondary; 507 508 /** 509 * Margin between items. 510 */ 511 private int mHorizontalMargin; 512 /** 513 * Margin between items vertically. 514 */ 515 private int mVerticalMargin; 516 /** 517 * Margin in main direction. 518 */ 519 private int mMarginPrimary; 520 /** 521 * Margin in second direction. 522 */ 523 private int mMarginSecondary; 524 /** 525 * How to position child in secondary direction. 526 */ 527 private int mGravity = Gravity.START | Gravity.TOP; 528 /** 529 * The number of rows in the grid. 530 */ 531 private int mNumRows; 532 /** 533 * Number of rows requested, can be 0 to be determined by parent size and 534 * rowHeight. 535 */ 536 private int mNumRowsRequested = 1; 537 538 /** 539 * Saves grid information of each view. 540 */ 541 Grid mGrid; 542 543 /** 544 * Focus Scroll strategy. 545 */ 546 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 547 /** 548 * Defines how item view is aligned in the window. 549 */ 550 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 551 552 /** 553 * Defines how item view is aligned. 554 */ 555 private final ItemAlignment mItemAlignment = new ItemAlignment(); 556 557 /** 558 * Dimensions of the view, width or height depending on orientation. 559 */ 560 private int mSizePrimary; 561 562 /** 563 * Allow DPAD key to navigate out at the front of the View (where position = 0), 564 * default is false. 565 */ 566 private boolean mFocusOutFront; 567 568 /** 569 * Allow DPAD key to navigate out at the end of the view, default is false. 570 */ 571 private boolean mFocusOutEnd; 572 573 /** 574 * True if focus search is disabled. 575 */ 576 private boolean mFocusSearchDisabled; 577 578 /** 579 * True if prune child, might be disabled during transition. 580 */ 581 private boolean mPruneChild = true; 582 583 /** 584 * True if scroll content, might be disabled during transition. 585 */ 586 private boolean mScrollEnabled = true; 587 588 /** 589 * Temporary variable: an int array of length=2. 590 */ 591 private static int[] sTwoInts = new int[2]; 592 593 /** 594 * Set to true for RTL layout in horizontal orientation 595 */ 596 private boolean mReverseFlowPrimary = false; 597 598 /** 599 * Set to true for RTL layout in vertical orientation 600 */ 601 private boolean mReverseFlowSecondary = false; 602 603 /** 604 * Temporaries used for measuring. 605 */ 606 private int[] mMeasuredDimension = new int[2]; 607 608 final ViewsStateBundle mChildrenStates = new ViewsStateBundle(); 609 610 public GridLayoutManager(BaseGridView baseGridView) { 611 mBaseGridView = baseGridView; 612 } 613 614 public void setOrientation(int orientation) { 615 if (orientation != HORIZONTAL && orientation != VERTICAL) { 616 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 617 return; 618 } 619 620 mOrientation = orientation; 621 mWindowAlignment.setOrientation(orientation); 622 mItemAlignment.setOrientation(orientation); 623 mForceFullLayout = true; 624 } 625 626 public void onRtlPropertiesChanged(int layoutDirection) { 627 if (mOrientation == HORIZONTAL) { 628 mReverseFlowPrimary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 629 mReverseFlowSecondary = false; 630 } else { 631 mReverseFlowSecondary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 632 mReverseFlowPrimary = false; 633 } 634 mWindowAlignment.horizontal.setReversedFlow(layoutDirection == View.LAYOUT_DIRECTION_RTL); 635 } 636 637 public int getFocusScrollStrategy() { 638 return mFocusScrollStrategy; 639 } 640 641 public void setFocusScrollStrategy(int focusScrollStrategy) { 642 mFocusScrollStrategy = focusScrollStrategy; 643 } 644 645 public void setWindowAlignment(int windowAlignment) { 646 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 647 } 648 649 public int getWindowAlignment() { 650 return mWindowAlignment.mainAxis().getWindowAlignment(); 651 } 652 653 public void setWindowAlignmentOffset(int alignmentOffset) { 654 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 655 } 656 657 public int getWindowAlignmentOffset() { 658 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 659 } 660 661 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 662 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 663 } 664 665 public float getWindowAlignmentOffsetPercent() { 666 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 667 } 668 669 public void setItemAlignmentOffset(int alignmentOffset) { 670 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 671 updateChildAlignments(); 672 } 673 674 public int getItemAlignmentOffset() { 675 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 676 } 677 678 public void setItemAlignmentOffsetWithPadding(boolean withPadding) { 679 mItemAlignment.mainAxis().setItemAlignmentOffsetWithPadding(withPadding); 680 updateChildAlignments(); 681 } 682 683 public boolean isItemAlignmentOffsetWithPadding() { 684 return mItemAlignment.mainAxis().isItemAlignmentOffsetWithPadding(); 685 } 686 687 public void setItemAlignmentOffsetPercent(float offsetPercent) { 688 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 689 updateChildAlignments(); 690 } 691 692 public float getItemAlignmentOffsetPercent() { 693 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 694 } 695 696 public void setItemAlignmentViewId(int viewId) { 697 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 698 updateChildAlignments(); 699 } 700 701 public int getItemAlignmentViewId() { 702 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 703 } 704 705 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 706 mFocusOutFront = throughFront; 707 mFocusOutEnd = throughEnd; 708 } 709 710 public void setNumRows(int numRows) { 711 if (numRows < 0) throw new IllegalArgumentException(); 712 mNumRowsRequested = numRows; 713 mForceFullLayout = true; 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 getViewCenter(View view) { 891 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 892 } 893 894 private int getViewCenterSecondary(View view) { 895 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 896 } 897 898 private int getViewCenterX(View v) { 899 LayoutParams p = (LayoutParams) v.getLayoutParams(); 900 return p.getOpticalLeft(v) + p.getAlignX(); 901 } 902 903 private int getViewCenterY(View v) { 904 LayoutParams p = (LayoutParams) v.getLayoutParams(); 905 return p.getOpticalTop(v) + p.getAlignY(); 906 } 907 908 /** 909 * Save Recycler and State for convenience. Must be paired with leaveContext(). 910 */ 911 private void saveContext(Recycler recycler, State state) { 912 if (mRecycler != null || mState != null) { 913 Log.e(TAG, "Recycler information was not released, bug!"); 914 } 915 mRecycler = recycler; 916 mState = state; 917 } 918 919 /** 920 * Discard saved Recycler and State. 921 */ 922 private void leaveContext() { 923 mRecycler = null; 924 mState = null; 925 } 926 927 /** 928 * Re-initialize data structures for a data change or handling invisible 929 * selection. The method tries its best to preserve position information so 930 * that staggered grid looks same before and after re-initialize. 931 * @return true if can fastRelayout() 932 */ 933 private boolean layoutInit() { 934 boolean focusViewWasInTree = mGrid != null && mFocusPosition >= 0 935 && mFocusPosition >= mGrid.getFirstVisibleIndex() 936 && mFocusPosition <= mGrid.getLastVisibleIndex(); 937 final int newItemCount = mState.getItemCount(); 938 if (newItemCount == 0) { 939 mFocusPosition = NO_POSITION; 940 } else if (mFocusPosition >= newItemCount) { 941 mFocusPosition = newItemCount - 1; 942 } else if (mFocusPosition == NO_POSITION && newItemCount > 0) { 943 // if focus position is never set before, initialize it to 0 944 mFocusPosition = 0; 945 } 946 if (!mState.didStructureChange() && mGrid.getFirstVisibleIndex() >= 0 && 947 !mForceFullLayout && mGrid != null) { 948 updateScrollController(); 949 updateScrollSecondAxis(); 950 mGrid.setMargin(mMarginPrimary); 951 if (!focusViewWasInTree && mFocusPosition != NO_POSITION) { 952 mGrid.setStart(mFocusPosition); 953 } 954 return true; 955 } else { 956 mForceFullLayout = false; 957 int firstVisibleIndex = focusViewWasInTree ? mGrid.getFirstVisibleIndex() : 0; 958 959 if (mGrid == null || mNumRows != mGrid.getNumRows() || 960 mReverseFlowPrimary != mGrid.isReversedFlow()) { 961 mGrid = Grid.createStaggeredMultipleRows(mNumRows); 962 mGrid.setProvider(mGridProvider); 963 mGrid.setReversedFlow(mReverseFlowPrimary); 964 } 965 initScrollController(); 966 updateScrollSecondAxis(); 967 mGrid.setMargin(mMarginPrimary); 968 detachAndScrapAttachedViews(mRecycler); 969 mGrid.resetVisibleIndex(); 970 if (mFocusPosition == NO_POSITION) { 971 mBaseGridView.clearFocus(); 972 } 973 mWindowAlignment.mainAxis().invalidateScrollMin(); 974 mWindowAlignment.mainAxis().invalidateScrollMax(); 975 if (focusViewWasInTree && firstVisibleIndex <= mFocusPosition) { 976 // if focusView was in tree, we will add item from first visible item 977 mGrid.setStart(firstVisibleIndex); 978 } else { 979 // if focusView was not in tree, it's probably because focus position jumped 980 // far away from visible range, so use mFocusPosition as start 981 mGrid.setStart(mFocusPosition); 982 } 983 return false; 984 } 985 } 986 987 private int getRowSizeSecondary(int rowIndex) { 988 if (mFixedRowSizeSecondary != 0) { 989 return mFixedRowSizeSecondary; 990 } 991 if (mRowSizeSecondary == null) { 992 return 0; 993 } 994 return mRowSizeSecondary[rowIndex]; 995 } 996 997 private int getRowStartSecondary(int rowIndex) { 998 int start = 0; 999 // Iterate from left to right, which is a different index traversal 1000 // in RTL flow 1001 if (mReverseFlowSecondary) { 1002 for (int i = mNumRows-1; i > rowIndex; i--) { 1003 start += getRowSizeSecondary(i) + mMarginSecondary; 1004 } 1005 } else { 1006 for (int i = 0; i < rowIndex; i++) { 1007 start += getRowSizeSecondary(i) + mMarginSecondary; 1008 } 1009 } 1010 return start; 1011 } 1012 1013 private int getSizeSecondary() { 1014 int rightmostIndex = mReverseFlowSecondary ? 0 : mNumRows - 1; 1015 return getRowStartSecondary(rightmostIndex) + getRowSizeSecondary(rightmostIndex); 1016 } 1017 1018 private void measureScrapChild(int position, int widthSpec, int heightSpec, 1019 int[] measuredDimension) { 1020 View view = mRecycler.getViewForPosition(position); 1021 if (view != null) { 1022 LayoutParams p = (LayoutParams) view.getLayoutParams(); 1023 int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, 1024 getPaddingLeft() + getPaddingRight(), p.width); 1025 int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, 1026 getPaddingTop() + getPaddingBottom(), p.height); 1027 view.measure(childWidthSpec, childHeightSpec); 1028 measuredDimension[0] = view.getMeasuredWidth(); 1029 measuredDimension[1] = view.getMeasuredHeight(); 1030 mRecycler.recycleView(view); 1031 } 1032 } 1033 1034 private boolean processRowSizeSecondary(boolean measure) { 1035 if (mFixedRowSizeSecondary != 0) { 1036 return false; 1037 } 1038 1039 if (TRACE) TraceHelper.beginSection("processRowSizeSecondary"); 1040 CircularIntArray[] rows = mGrid == null ? null : mGrid.getItemPositionsInRows(); 1041 boolean changed = false; 1042 int scrapChildWidth = -1; 1043 int scrapChildHeight = -1; 1044 1045 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 1046 CircularIntArray row = rows == null ? null : rows[rowIndex]; 1047 final int rowItemsPairCount = row == null ? 0 : row.size(); 1048 int rowSize = -1; 1049 for (int rowItemPairIndex = 0; rowItemPairIndex < rowItemsPairCount; 1050 rowItemPairIndex += 2) { 1051 final int rowIndexStart = row.get(rowItemPairIndex); 1052 final int rowIndexEnd = row.get(rowItemPairIndex + 1); 1053 for (int i = rowIndexStart; i <= rowIndexEnd; i++) { 1054 final View view = findViewByPosition(i); 1055 if (view == null) { 1056 continue; 1057 } 1058 if (measure && view.isLayoutRequested()) { 1059 measureChild(view); 1060 } 1061 final int secondarySize = mOrientation == HORIZONTAL ? 1062 view.getMeasuredHeight() : view.getMeasuredWidth(); 1063 if (secondarySize > rowSize) { 1064 rowSize = secondarySize; 1065 } 1066 } 1067 } 1068 1069 final int itemCount = mState.getItemCount(); 1070 if (measure && rowSize < 0 && itemCount > 0) { 1071 if (scrapChildWidth < 0 && scrapChildHeight < 0) { 1072 int position; 1073 if (mFocusPosition == NO_POSITION) { 1074 position = 0; 1075 } else if (mFocusPosition >= itemCount) { 1076 position = itemCount - 1; 1077 } else { 1078 position = mFocusPosition; 1079 } 1080 measureScrapChild(position, 1081 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1082 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1083 mMeasuredDimension); 1084 scrapChildWidth = mMeasuredDimension[0]; 1085 scrapChildHeight = mMeasuredDimension[1]; 1086 if (DEBUG) Log.v(TAG, "measured scrap child: " + scrapChildWidth + 1087 " " + scrapChildHeight); 1088 } 1089 rowSize = mOrientation == HORIZONTAL ? scrapChildHeight : scrapChildWidth; 1090 } 1091 if (rowSize < 0) { 1092 rowSize = 0; 1093 } 1094 if (mRowSizeSecondary[rowIndex] != rowSize) { 1095 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 1096 ", " + rowSize); 1097 mRowSizeSecondary[rowIndex] = rowSize; 1098 changed = true; 1099 } 1100 } 1101 1102 if (TRACE) TraceHelper.endSection(); 1103 return changed; 1104 } 1105 1106 /** 1107 * Checks if we need to update row secondary sizes. 1108 */ 1109 private void updateRowSecondarySizeRefresh() { 1110 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 1111 if (mRowSecondarySizeRefresh) { 1112 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 1113 forceRequestLayout(); 1114 } 1115 } 1116 1117 private void forceRequestLayout() { 1118 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 1119 // RecyclerView prevents us from requesting layout in many cases 1120 // (during layout, during scroll, etc.) 1121 // For secondary row size wrap_content support we currently need a 1122 // second layout pass to update the measured size after having measured 1123 // and added child views in layoutChildren. 1124 // Force the second layout by posting a delayed runnable. 1125 // TODO: investigate allowing a second layout pass, 1126 // or move child add/measure logic to the measure phase. 1127 ViewCompat.postOnAnimation(mBaseGridView, mRequestLayoutRunnable); 1128 } 1129 1130 private final Runnable mRequestLayoutRunnable = new Runnable() { 1131 @Override 1132 public void run() { 1133 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 1134 requestLayout(); 1135 } 1136 }; 1137 1138 @Override 1139 public void onMeasure(Recycler recycler, State state, int widthSpec, int heightSpec) { 1140 saveContext(recycler, state); 1141 1142 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 1143 int measuredSizeSecondary; 1144 if (mOrientation == HORIZONTAL) { 1145 sizePrimary = MeasureSpec.getSize(widthSpec); 1146 sizeSecondary = MeasureSpec.getSize(heightSpec); 1147 modeSecondary = MeasureSpec.getMode(heightSpec); 1148 paddingSecondary = getPaddingTop() + getPaddingBottom(); 1149 } else { 1150 sizeSecondary = MeasureSpec.getSize(widthSpec); 1151 sizePrimary = MeasureSpec.getSize(heightSpec); 1152 modeSecondary = MeasureSpec.getMode(widthSpec); 1153 paddingSecondary = getPaddingLeft() + getPaddingRight(); 1154 } 1155 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 1156 " heightSpec " + Integer.toHexString(heightSpec) + 1157 " modeSecondary " + Integer.toHexString(modeSecondary) + 1158 " sizeSecondary " + sizeSecondary + " " + this); 1159 1160 mMaxSizeSecondary = sizeSecondary; 1161 1162 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 1163 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1164 mFixedRowSizeSecondary = 0; 1165 1166 if (mRowSizeSecondary == null || mRowSizeSecondary.length != mNumRows) { 1167 mRowSizeSecondary = new int[mNumRows]; 1168 } 1169 1170 // Measure all current children and update cached row heights 1171 processRowSizeSecondary(true); 1172 1173 switch (modeSecondary) { 1174 case MeasureSpec.UNSPECIFIED: 1175 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 1176 break; 1177 case MeasureSpec.AT_MOST: 1178 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 1179 mMaxSizeSecondary); 1180 break; 1181 case MeasureSpec.EXACTLY: 1182 measuredSizeSecondary = mMaxSizeSecondary; 1183 break; 1184 default: 1185 throw new IllegalStateException("wrong spec"); 1186 } 1187 1188 } else { 1189 switch (modeSecondary) { 1190 case MeasureSpec.UNSPECIFIED: 1191 if (mRowSizeSecondaryRequested == 0) { 1192 if (mOrientation == HORIZONTAL) { 1193 throw new IllegalStateException("Must specify rowHeight or view height"); 1194 } else { 1195 throw new IllegalStateException("Must specify columnWidth or view width"); 1196 } 1197 } 1198 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1199 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1200 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1201 * (mNumRows - 1) + paddingSecondary; 1202 break; 1203 case MeasureSpec.AT_MOST: 1204 case MeasureSpec.EXACTLY: 1205 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 1206 mNumRows = 1; 1207 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 1208 } else if (mNumRowsRequested == 0) { 1209 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1210 mNumRows = (sizeSecondary + mMarginSecondary) 1211 / (mRowSizeSecondaryRequested + mMarginSecondary); 1212 } else if (mRowSizeSecondaryRequested == 0) { 1213 mNumRows = mNumRowsRequested; 1214 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 1215 * (mNumRows - 1)) / mNumRows; 1216 } else { 1217 mNumRows = mNumRowsRequested; 1218 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1219 } 1220 measuredSizeSecondary = sizeSecondary; 1221 if (modeSecondary == MeasureSpec.AT_MOST) { 1222 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1223 * (mNumRows - 1) + paddingSecondary; 1224 if (childrenSize < measuredSizeSecondary) { 1225 measuredSizeSecondary = childrenSize; 1226 } 1227 } 1228 break; 1229 default: 1230 throw new IllegalStateException("wrong spec"); 1231 } 1232 } 1233 if (mOrientation == HORIZONTAL) { 1234 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1235 } else { 1236 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1237 } 1238 if (DEBUG) { 1239 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1240 " measuredSizeSecondary " + measuredSizeSecondary + 1241 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1242 " mNumRows " + mNumRows); 1243 } 1244 leaveContext(); 1245 } 1246 1247 private void measureChild(View child) { 1248 if (TRACE) TraceHelper.beginSection("measureChild"); 1249 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1250 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1251 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1252 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1253 int widthSpec, heightSpec; 1254 1255 if (mOrientation == HORIZONTAL) { 1256 widthSpec = ViewGroup.getChildMeasureSpec( 1257 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1258 0, lp.width); 1259 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1260 } else { 1261 heightSpec = ViewGroup.getChildMeasureSpec( 1262 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1263 0, lp.height); 1264 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1265 } 1266 child.measure(widthSpec, heightSpec); 1267 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1268 " widthSpec " + Integer.toHexString(widthSpec) + 1269 " heightSpec " + Integer.toHexString(heightSpec) + 1270 " measuredWidth " + child.getMeasuredWidth() + 1271 " measuredHeight " + child.getMeasuredHeight()); 1272 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1273 if (TRACE) TraceHelper.endSection(); 1274 } 1275 1276 private Grid.Provider mGridProvider = new Grid.Provider() { 1277 1278 @Override 1279 public int getCount() { 1280 return mState.getItemCount(); 1281 } 1282 1283 @Override 1284 public int createItem(int index, boolean append, Object[] item) { 1285 if (TRACE) TraceHelper.beginSection("createItem"); 1286 if (TRACE) TraceHelper.beginSection("getview"); 1287 View v = getViewForPosition(index); 1288 if (TRACE) TraceHelper.endSection(); 1289 // See recyclerView docs: we don't need re-add scraped view if it was removed. 1290 if (!((RecyclerView.LayoutParams) v.getLayoutParams()).isItemRemoved()) { 1291 if (TRACE) TraceHelper.beginSection("addView"); 1292 if (append) { 1293 addView(v); 1294 } else { 1295 addView(v, 0); 1296 } 1297 if (TRACE) TraceHelper.endSection(); 1298 if (mChildVisibility != -1) { 1299 v.setVisibility(mChildVisibility); 1300 } 1301 1302 if (mPendingMoveSmoothScroller != null) { 1303 mPendingMoveSmoothScroller.consumePendingMovesBeforeLayout(); 1304 } 1305 if (!mInLayout) { 1306 // when we are appending item during scroll pass and the item's position 1307 // matches the mFocusPosition, we should signal a childSelected event. 1308 // However if we are still running PendingMoveSmoothScroller, we defer and 1309 // signal the event in PendingMoveSmoothScroller.onStop(). This can 1310 // avoid lots of childSelected events during a long smooth scrolling and 1311 // increase performance. 1312 if (index == mFocusPosition && (mPendingMoveSmoothScroller == null 1313 || mPendingMoveSmoothScroller.mPendingMoves == 0)) { 1314 dispatchChildSelected(); 1315 } 1316 } else if (!mInFastRelayout) { 1317 // fastRelayout will dispatch event at end of onLayoutChildren(). 1318 // For full layout, two situations here: 1319 // 1. mInLayoutSearchFocus is false, dispatchChildSelected() at mFocusPosition. 1320 // 2. mInLayoutSearchFocus is true: dispatchChildSelected() on first child 1321 // equal to or after mFocusPosition that can take focus. 1322 if (!mInLayoutSearchFocus && index == mFocusPosition) { 1323 dispatchChildSelected(); 1324 } else if (mInLayoutSearchFocus && index >= mFocusPosition 1325 && v.hasFocusable()) { 1326 mFocusPosition = index; 1327 mInLayoutSearchFocus = false; 1328 dispatchChildSelected(); 1329 } 1330 } 1331 measureChild(v); 1332 } 1333 item[0] = v; 1334 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1335 } 1336 1337 @Override 1338 public void addItem(Object item, int index, int length, int rowIndex, int edge) { 1339 View v = (View) item; 1340 int start, end; 1341 if (edge == Integer.MIN_VALUE || edge == Integer.MAX_VALUE) { 1342 edge = !mGrid.isReversedFlow() ? mWindowAlignment.mainAxis().getPaddingLow() 1343 : mWindowAlignment.mainAxis().getSize() 1344 - mWindowAlignment.mainAxis().getPaddingHigh(); 1345 } 1346 boolean edgeIsMin = !mGrid.isReversedFlow(); 1347 if (edgeIsMin) { 1348 start = edge; 1349 end = edge + length; 1350 } else { 1351 start = edge - length; 1352 end = edge; 1353 } 1354 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1355 mChildrenStates.loadView(v, index); 1356 layoutChild(rowIndex, v, start, end, startSecondary); 1357 if (DEBUG) { 1358 Log.d(getTag(), "addView " + index + " " + v); 1359 } 1360 if (TRACE) TraceHelper.endSection(); 1361 1362 if (index == mGrid.getFirstVisibleIndex()) { 1363 if (!mGrid.isReversedFlow()) { 1364 updateScrollMin(); 1365 } else { 1366 updateScrollMax(); 1367 } 1368 } 1369 if (index == mGrid.getLastVisibleIndex()) { 1370 if (!mGrid.isReversedFlow()) { 1371 updateScrollMax(); 1372 } else { 1373 updateScrollMin(); 1374 } 1375 } 1376 if (!mInLayout && mPendingMoveSmoothScroller != null) { 1377 mPendingMoveSmoothScroller.consumePendingMovesAfterLayout(); 1378 } 1379 if (mChildLaidOutListener != null) { 1380 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(v); 1381 mChildLaidOutListener.onChildLaidOut(mBaseGridView, v, index, 1382 vh == null ? NO_ID : vh.getItemId()); 1383 } 1384 } 1385 1386 @Override 1387 public void removeItem(int index) { 1388 if (TRACE) TraceHelper.beginSection("removeItem"); 1389 View v = findViewByPosition(index); 1390 if (mInLayout) { 1391 detachAndScrapView(v, mRecycler); 1392 } else { 1393 removeAndRecycleView(v, mRecycler); 1394 } 1395 if (TRACE) TraceHelper.endSection(); 1396 } 1397 1398 @Override 1399 public int getEdge(int index) { 1400 if (mReverseFlowPrimary) { 1401 return getViewMax(findViewByPosition(index)); 1402 } else { 1403 return getViewMin(findViewByPosition(index)); 1404 } 1405 } 1406 1407 @Override 1408 public int getSize(int index) { 1409 final View v = findViewByPosition(index); 1410 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1411 } 1412 }; 1413 1414 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1415 if (TRACE) TraceHelper.beginSection("layoutChild"); 1416 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1417 : v.getMeasuredWidth(); 1418 if (mFixedRowSizeSecondary > 0) { 1419 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1420 } 1421 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1422 final int horizontalGravity = (mReverseFlowPrimary || mReverseFlowSecondary) ? 1423 Gravity.getAbsoluteGravity(mGravity & Gravity.RELATIVE_HORIZONTAL_GRAVITY_MASK, View.LAYOUT_DIRECTION_RTL) : 1424 mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1425 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1426 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1427 // do nothing 1428 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1429 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1430 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1431 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1432 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1433 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1434 } 1435 int left, top, right, bottom; 1436 if (mOrientation == HORIZONTAL) { 1437 left = start; 1438 top = startSecondary; 1439 right = end; 1440 bottom = startSecondary + sizeSecondary; 1441 } else { 1442 top = start; 1443 left = startSecondary; 1444 bottom = end; 1445 right = startSecondary + sizeSecondary; 1446 } 1447 v.layout(left, top, right, bottom); 1448 updateChildOpticalInsets(v, left, top, right, bottom); 1449 updateChildAlignments(v); 1450 if (TRACE) TraceHelper.endSection(); 1451 } 1452 1453 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1454 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1455 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1456 v.getRight() - right, v.getBottom() - bottom); 1457 } 1458 1459 private void updateChildAlignments(View v) { 1460 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1461 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1462 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1463 } 1464 1465 private void updateChildAlignments() { 1466 for (int i = 0, c = getChildCount(); i < c; i++) { 1467 updateChildAlignments(getChildAt(i)); 1468 } 1469 } 1470 1471 private void removeInvisibleViewsAtEnd() { 1472 if (mPruneChild) { 1473 mGrid.removeInvisibleItemsAtEnd(mFocusPosition, 1474 mReverseFlowPrimary ? 0 : mSizePrimary); 1475 } 1476 } 1477 1478 private void removeInvisibleViewsAtFront() { 1479 if (mPruneChild) { 1480 mGrid.removeInvisibleItemsAtFront(mFocusPosition, 1481 mReverseFlowPrimary ? mSizePrimary : 0); 1482 } 1483 } 1484 1485 private boolean appendOneColumnVisibleItems() { 1486 return mGrid.appendOneColumnVisibleItems(); 1487 } 1488 1489 private boolean prependOneColumnVisibleItems() { 1490 return mGrid.prependOneColumnVisibleItems(); 1491 } 1492 1493 private void appendVisibleItems() { 1494 mGrid.appendVisibleItems(mReverseFlowPrimary ? 0 : mSizePrimary); 1495 } 1496 1497 private void prependVisibleItems() { 1498 mGrid.prependVisibleItems(mReverseFlowPrimary ? mSizePrimary : 0); 1499 } 1500 1501 /** 1502 * Fast layout when there is no structure change, adapter change, etc. 1503 * It will layout all views was layout requested or updated, until hit a view 1504 * with different size, then it break and detachAndScrap all views after that. 1505 */ 1506 private void fastRelayout() { 1507 boolean invalidateAfter = false; 1508 final int childCount = getChildCount(); 1509 int position = -1; 1510 for (int index = 0; index < childCount; index++) { 1511 View view = getChildAt(index); 1512 position = getPositionByIndex(index); 1513 Grid.Location location = mGrid.getLocation(position); 1514 if (location == null) { 1515 if (DEBUG) Log.w(getTag(), "fastRelayout(): no Location at " + position); 1516 invalidateAfter = true; 1517 break; 1518 } 1519 1520 int startSecondary = getRowStartSecondary(location.row) - mScrollOffsetSecondary; 1521 int primarySize, end; 1522 int start = getViewMin(view); 1523 int oldPrimarySize = (mOrientation == HORIZONTAL) ? 1524 view.getMeasuredWidth() : 1525 view.getMeasuredHeight(); 1526 1527 LayoutParams lp = (LayoutParams) view.getLayoutParams(); 1528 if (lp.viewNeedsUpdate()) { 1529 int viewIndex = mBaseGridView.indexOfChild(view); 1530 detachAndScrapView(view, mRecycler); 1531 view = getViewForPosition(position); 1532 addView(view, viewIndex); 1533 } 1534 1535 if (view.isLayoutRequested()) { 1536 measureChild(view); 1537 } 1538 if (mOrientation == HORIZONTAL) { 1539 primarySize = view.getMeasuredWidth(); 1540 end = start + primarySize; 1541 } else { 1542 primarySize = view.getMeasuredHeight(); 1543 end = start + primarySize; 1544 } 1545 layoutChild(location.row, view, start, end, startSecondary); 1546 if (oldPrimarySize != primarySize) { 1547 // size changed invalidate remaining Locations 1548 if (DEBUG) Log.d(getTag(), "fastRelayout: view size changed at " + position); 1549 invalidateAfter = true; 1550 break; 1551 } 1552 } 1553 if (invalidateAfter) { 1554 final int savedLastPos = mGrid.getLastVisibleIndex(); 1555 mGrid.invalidateItemsAfter(position); 1556 if (mPruneChild) { 1557 // in regular prune child mode, we just append items up to edge limit 1558 appendVisibleItems(); 1559 if (mFocusPosition >= 0 && mFocusPosition <= savedLastPos) { 1560 // make sure add focus view back: the view might be outside edge limit 1561 // when there is delta in onLayoutChildren(). 1562 while (mGrid.getLastVisibleIndex() < mFocusPosition) { 1563 mGrid.appendOneColumnVisibleItems(); 1564 } 1565 } 1566 } else { 1567 // prune disabled(e.g. in RowsFragment transition): append all removed items 1568 while (mGrid.appendOneColumnVisibleItems() 1569 && mGrid.getLastVisibleIndex() < savedLastPos); 1570 } 1571 } 1572 updateScrollMin(); 1573 updateScrollMax(); 1574 updateScrollSecondAxis(); 1575 } 1576 1577 public void removeAndRecycleAllViews(RecyclerView.Recycler recycler) { 1578 if (TRACE) TraceHelper.beginSection("removeAndRecycleAllViews"); 1579 if (DEBUG) Log.v(TAG, "removeAndRecycleAllViews " + getChildCount()); 1580 for (int i = getChildCount() - 1; i >= 0; i--) { 1581 removeAndRecycleViewAt(i, recycler); 1582 } 1583 if (TRACE) TraceHelper.endSection(); 1584 } 1585 1586 // Lays out items based on the current scroll position 1587 @Override 1588 public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) { 1589 if (DEBUG) { 1590 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1591 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1592 + " inPreLayout " + state.isPreLayout() 1593 + " didStructureChange " + state.didStructureChange() 1594 + " mForceFullLayout " + mForceFullLayout); 1595 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1596 } 1597 1598 if (mNumRows == 0) { 1599 // haven't done measure yet 1600 return; 1601 } 1602 final int itemCount = state.getItemCount(); 1603 if (itemCount < 0) { 1604 return; 1605 } 1606 1607 if (!mLayoutEnabled) { 1608 discardLayoutInfo(); 1609 removeAndRecycleAllViews(recycler); 1610 return; 1611 } 1612 mInLayout = true; 1613 1614 final boolean scrollToFocus = !isSmoothScrolling() 1615 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED; 1616 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1617 mFocusPosition = mFocusPosition + mFocusPositionOffset; 1618 mFocusPositionOffset = 0; 1619 } 1620 saveContext(recycler, state); 1621 1622 // Track the old focus view so we can adjust our system scroll position 1623 // so that any scroll animations happening now will remain valid. 1624 // We must use same delta in Pre Layout (if prelayout exists) and second layout. 1625 // So we cache the deltas in PreLayout and use it in second layout. 1626 int delta = 0, deltaSecondary = 0; 1627 if (mFocusPosition != NO_POSITION && scrollToFocus 1628 && mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE) { 1629 // FIXME: we should get the remaining scroll animation offset from RecyclerView 1630 View focusView = findViewByPosition(mFocusPosition); 1631 if (focusView != null) { 1632 delta = mWindowAlignment.mainAxis().getSystemScrollPos(mScrollOffsetPrimary 1633 + getViewCenter(focusView), false, false) - mScrollOffsetPrimary; 1634 deltaSecondary = mWindowAlignment.secondAxis().getSystemScrollPos( 1635 mScrollOffsetSecondary + getViewCenterSecondary(focusView), 1636 false, false) - mScrollOffsetSecondary; 1637 } 1638 } 1639 1640 boolean hadFocus = mBaseGridView.hasFocus(); 1641 int savedFocusPos = mFocusPosition; 1642 if (mInFastRelayout = layoutInit()) { 1643 fastRelayout(); 1644 // appends items till focus position. 1645 if (mFocusPosition != NO_POSITION) { 1646 View focusView = findViewByPosition(mFocusPosition); 1647 if (focusView != null) { 1648 if (scrollToFocus) { 1649 scrollToView(focusView, false); 1650 } 1651 if (hadFocus) { 1652 focusView.requestFocus(); 1653 } 1654 } 1655 } 1656 } else { 1657 mInLayoutSearchFocus = hadFocus; 1658 if (mFocusPosition != NO_POSITION) { 1659 // appends items till focus position. 1660 while (appendOneColumnVisibleItems() 1661 && findViewByPosition(mFocusPosition) == null) ; 1662 } 1663 // multiple rounds: scrollToView of first round may drag first/last child into 1664 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1665 int oldFirstVisible; 1666 int oldLastVisible; 1667 do { 1668 updateScrollMin(); 1669 updateScrollMax(); 1670 oldFirstVisible = mGrid.getFirstVisibleIndex(); 1671 oldLastVisible = mGrid.getLastVisibleIndex(); 1672 View focusView = findViewByPosition(mFocusPosition); 1673 // we need force to initialize the child view's position 1674 scrollToView(focusView, false); 1675 if (focusView != null && hadFocus) { 1676 focusView.requestFocus(); 1677 } 1678 appendVisibleItems(); 1679 prependVisibleItems(); 1680 removeInvisibleViewsAtFront(); 1681 removeInvisibleViewsAtEnd(); 1682 } while (mGrid.getFirstVisibleIndex() != oldFirstVisible || 1683 mGrid.getLastVisibleIndex() != oldLastVisible); 1684 } 1685 1686 if (scrollToFocus) { 1687 scrollDirectionPrimary(-delta); 1688 scrollDirectionSecondary(-deltaSecondary); 1689 } 1690 appendVisibleItems(); 1691 prependVisibleItems(); 1692 removeInvisibleViewsAtFront(); 1693 removeInvisibleViewsAtEnd(); 1694 1695 if (DEBUG) { 1696 StringWriter sw = new StringWriter(); 1697 PrintWriter pw = new PrintWriter(sw); 1698 mGrid.debugPrint(pw); 1699 Log.d(getTag(), sw.toString()); 1700 } 1701 1702 if (mRowSecondarySizeRefresh) { 1703 mRowSecondarySizeRefresh = false; 1704 } else { 1705 updateRowSecondarySizeRefresh(); 1706 } 1707 1708 // For fastRelayout, only dispatch event when focus position changes. 1709 if (mInFastRelayout && mFocusPosition != savedFocusPos) { 1710 dispatchChildSelected(); 1711 } else if (!mInFastRelayout && mInLayoutSearchFocus) { 1712 // For full layout we dispatchChildSelected() in createItem() unless searched all 1713 // children and found none is focusable then dispatchChildSelected() here. 1714 dispatchChildSelected(); 1715 } 1716 1717 mInLayout = false; 1718 leaveContext(); 1719 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1720 } 1721 1722 private void offsetChildrenSecondary(int increment) { 1723 final int childCount = getChildCount(); 1724 if (mOrientation == HORIZONTAL) { 1725 for (int i = 0; i < childCount; i++) { 1726 getChildAt(i).offsetTopAndBottom(increment); 1727 } 1728 } else { 1729 for (int i = 0; i < childCount; i++) { 1730 getChildAt(i).offsetLeftAndRight(increment); 1731 } 1732 } 1733 } 1734 1735 private void offsetChildrenPrimary(int increment) { 1736 final int childCount = getChildCount(); 1737 if (mOrientation == VERTICAL) { 1738 for (int i = 0; i < childCount; i++) { 1739 getChildAt(i).offsetTopAndBottom(increment); 1740 } 1741 } else { 1742 for (int i = 0; i < childCount; i++) { 1743 getChildAt(i).offsetLeftAndRight(increment); 1744 } 1745 } 1746 } 1747 1748 @Override 1749 public int scrollHorizontallyBy(int dx, Recycler recycler, RecyclerView.State state) { 1750 if (DEBUG) Log.v(getTag(), "scrollHorizontallyBy " + dx); 1751 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1752 return 0; 1753 } 1754 saveContext(recycler, state); 1755 int result; 1756 if (mOrientation == HORIZONTAL) { 1757 result = scrollDirectionPrimary(dx); 1758 } else { 1759 result = scrollDirectionSecondary(dx); 1760 } 1761 leaveContext(); 1762 return result; 1763 } 1764 1765 @Override 1766 public int scrollVerticallyBy(int dy, Recycler recycler, RecyclerView.State state) { 1767 if (DEBUG) Log.v(getTag(), "scrollVerticallyBy " + dy); 1768 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1769 return 0; 1770 } 1771 saveContext(recycler, state); 1772 int result; 1773 if (mOrientation == VERTICAL) { 1774 result = scrollDirectionPrimary(dy); 1775 } else { 1776 result = scrollDirectionSecondary(dy); 1777 } 1778 leaveContext(); 1779 return result; 1780 } 1781 1782 // scroll in main direction may add/prune views 1783 private int scrollDirectionPrimary(int da) { 1784 if (TRACE) TraceHelper.beginSection("scrollPrimary"); 1785 boolean isMaxUnknown = false, isMinUnknown = false; 1786 int minScroll = 0, maxScroll = 0; 1787 if (da > 0) { 1788 isMaxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1789 if (!isMaxUnknown) { 1790 maxScroll = mWindowAlignment.mainAxis().getMaxScroll(); 1791 if (mScrollOffsetPrimary + da > maxScroll) { 1792 da = maxScroll - mScrollOffsetPrimary; 1793 } 1794 } 1795 } else if (da < 0) { 1796 isMinUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1797 if (!isMinUnknown) { 1798 minScroll = mWindowAlignment.mainAxis().getMinScroll(); 1799 if (mScrollOffsetPrimary + da < minScroll) { 1800 da = minScroll - mScrollOffsetPrimary; 1801 } 1802 } 1803 } 1804 if (da == 0) { 1805 if (TRACE) TraceHelper.endSection(); 1806 return 0; 1807 } 1808 offsetChildrenPrimary(-da); 1809 mScrollOffsetPrimary += da; 1810 if (mInLayout) { 1811 if (TRACE) TraceHelper.endSection(); 1812 return da; 1813 } 1814 1815 int childCount = getChildCount(); 1816 boolean updated; 1817 1818 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1819 prependVisibleItems(); 1820 } else { 1821 appendVisibleItems(); 1822 } 1823 updated = getChildCount() > childCount; 1824 childCount = getChildCount(); 1825 1826 if (TRACE) TraceHelper.beginSection("remove"); 1827 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1828 removeInvisibleViewsAtEnd(); 1829 } else { 1830 removeInvisibleViewsAtFront(); 1831 } 1832 if (TRACE) TraceHelper.endSection(); 1833 updated |= getChildCount() < childCount; 1834 if (updated) { 1835 updateRowSecondarySizeRefresh(); 1836 } 1837 1838 mBaseGridView.invalidate(); 1839 if (TRACE) TraceHelper.endSection(); 1840 return da; 1841 } 1842 1843 // scroll in second direction will not add/prune views 1844 private int scrollDirectionSecondary(int dy) { 1845 if (dy == 0) { 1846 return 0; 1847 } 1848 offsetChildrenSecondary(-dy); 1849 mScrollOffsetSecondary += dy; 1850 mBaseGridView.invalidate(); 1851 return dy; 1852 } 1853 1854 private void updateScrollMax() { 1855 int highVisiblePos = (!mReverseFlowPrimary) ? mGrid.getLastVisibleIndex() 1856 : mGrid.getFirstVisibleIndex(); 1857 int highMaxPos = (!mReverseFlowPrimary) ? mState.getItemCount() - 1 : 0; 1858 if (highVisiblePos < 0) { 1859 return; 1860 } 1861 final boolean highAvailable = highVisiblePos == highMaxPos; 1862 final boolean maxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1863 if (!highAvailable && maxUnknown) { 1864 return; 1865 } 1866 int maxEdge = mGrid.findRowMax(true, sTwoInts) + mScrollOffsetPrimary; 1867 int rowIndex = sTwoInts[0]; 1868 int pos = sTwoInts[1]; 1869 int savedMaxEdge = mWindowAlignment.mainAxis().getMaxEdge(); 1870 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1871 int maxScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1872 mWindowAlignment.mainAxis().setMaxEdge(savedMaxEdge); 1873 1874 if (highAvailable) { 1875 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1876 mWindowAlignment.mainAxis().setMaxScroll(maxScroll); 1877 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge + 1878 " scrollMax to " + maxScroll); 1879 } else { 1880 mWindowAlignment.mainAxis().invalidateScrollMax(); 1881 if (DEBUG) Log.v(getTag(), "Invalidate scrollMax since it should be " 1882 + "greater than " + maxScroll); 1883 } 1884 } 1885 1886 private void updateScrollMin() { 1887 int lowVisiblePos = (!mReverseFlowPrimary) ? mGrid.getFirstVisibleIndex() 1888 : mGrid.getLastVisibleIndex(); 1889 int lowMinPos = (!mReverseFlowPrimary) ? 0 : mState.getItemCount() - 1; 1890 if (lowVisiblePos < 0) { 1891 return; 1892 } 1893 final boolean lowAvailable = lowVisiblePos == lowMinPos; 1894 final boolean minUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1895 if (!lowAvailable && minUnknown) { 1896 return; 1897 } 1898 int minEdge = mGrid.findRowMin(false, sTwoInts) + mScrollOffsetPrimary; 1899 int rowIndex = sTwoInts[0]; 1900 int pos = sTwoInts[1]; 1901 int savedMinEdge = mWindowAlignment.mainAxis().getMinEdge(); 1902 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1903 int minScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1904 mWindowAlignment.mainAxis().setMinEdge(savedMinEdge); 1905 1906 if (lowAvailable) { 1907 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1908 mWindowAlignment.mainAxis().setMinScroll(minScroll); 1909 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge + 1910 " scrollMin to " + minScroll); 1911 } else { 1912 mWindowAlignment.mainAxis().invalidateScrollMin(); 1913 if (DEBUG) Log.v(getTag(), "Invalidate scrollMin, since it should be " 1914 + "less than " + minScroll); 1915 } 1916 } 1917 1918 private void updateScrollSecondAxis() { 1919 mWindowAlignment.secondAxis().setMinEdge(0); 1920 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1921 } 1922 1923 private void initScrollController() { 1924 mWindowAlignment.reset(); 1925 mWindowAlignment.horizontal.setSize(getWidth()); 1926 mWindowAlignment.vertical.setSize(getHeight()); 1927 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1928 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1929 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1930 mScrollOffsetPrimary = -mWindowAlignment.mainAxis().getPaddingLow(); 1931 mScrollOffsetSecondary = -mWindowAlignment.secondAxis().getPaddingLow(); 1932 1933 if (DEBUG) { 1934 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1935 + " mWindowAlignment " + mWindowAlignment 1936 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1937 } 1938 } 1939 1940 private void updateScrollController() { 1941 // mScrollOffsetPrimary and mScrollOffsetSecondary includes the padding. 1942 // e.g. when topPadding is 16 for horizontal grid view, the initial 1943 // mScrollOffsetSecondary is -16. fastRelayout() put views based on offsets(not padding), 1944 // when padding changes to 20, we also need update mScrollOffsetSecondary to -20 before 1945 // fastRelayout() is performed 1946 int paddingPrimaryDiff, paddingSecondaryDiff; 1947 if (mOrientation == HORIZONTAL) { 1948 paddingPrimaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1949 paddingSecondaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1950 } else { 1951 paddingPrimaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1952 paddingSecondaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1953 } 1954 mScrollOffsetPrimary -= paddingPrimaryDiff; 1955 mScrollOffsetSecondary -= paddingSecondaryDiff; 1956 1957 mWindowAlignment.horizontal.setSize(getWidth()); 1958 mWindowAlignment.vertical.setSize(getHeight()); 1959 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1960 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1961 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1962 1963 if (DEBUG) { 1964 Log.v(getTag(), "updateScrollController mSizePrimary " + mSizePrimary 1965 + " mWindowAlignment " + mWindowAlignment 1966 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1967 } 1968 } 1969 1970 public void setSelection(RecyclerView parent, int position, 1971 int primaryScrollExtra) { 1972 setSelection(parent, position, false, primaryScrollExtra); 1973 } 1974 1975 public void setSelectionSmooth(RecyclerView parent, int position) { 1976 setSelection(parent, position, true, 0); 1977 } 1978 1979 public int getSelection() { 1980 return mFocusPosition; 1981 } 1982 1983 public void setSelection(RecyclerView parent, int position, boolean smooth, 1984 int primaryScrollExtra) { 1985 if (mFocusPosition != position && position != NO_POSITION 1986 || primaryScrollExtra != mPrimaryScrollExtra) { 1987 scrollToSelection(parent, position, smooth, primaryScrollExtra); 1988 } 1989 } 1990 1991 private void scrollToSelection(RecyclerView parent, int position, boolean smooth, 1992 int primaryScrollExtra) { 1993 if (TRACE) TraceHelper.beginSection("scrollToSelection"); 1994 mPrimaryScrollExtra = primaryScrollExtra; 1995 View view = findViewByPosition(position); 1996 if (view != null) { 1997 mInSelection = true; 1998 scrollToView(view, smooth); 1999 mInSelection = false; 2000 } else { 2001 mFocusPosition = position; 2002 mFocusPositionOffset = 0; 2003 if (!mLayoutEnabled) { 2004 return; 2005 } 2006 if (smooth) { 2007 if (!hasDoneFirstLayout()) { 2008 Log.w(getTag(), "setSelectionSmooth should " + 2009 "not be called before first layout pass"); 2010 return; 2011 } 2012 startPositionSmoothScroller(position); 2013 } else { 2014 mForceFullLayout = true; 2015 parent.requestLayout(); 2016 } 2017 } 2018 if (TRACE) TraceHelper.endSection(); 2019 } 2020 2021 void startPositionSmoothScroller(int position) { 2022 LinearSmoothScroller linearSmoothScroller = new GridLinearSmoothScroller() { 2023 @Override 2024 public PointF computeScrollVectorForPosition(int targetPosition) { 2025 if (getChildCount() == 0) { 2026 return null; 2027 } 2028 final int firstChildPos = getPosition(getChildAt(0)); 2029 // TODO We should be able to deduce direction from bounds of current and target 2030 // focus, rather than making assumptions about positions and directionality 2031 final boolean isStart = mReverseFlowPrimary ? targetPosition > firstChildPos 2032 : targetPosition < firstChildPos; 2033 final int direction = isStart ? -1 : 1; 2034 if (mOrientation == HORIZONTAL) { 2035 return new PointF(direction, 0); 2036 } else { 2037 return new PointF(0, direction); 2038 } 2039 } 2040 2041 }; 2042 linearSmoothScroller.setTargetPosition(position); 2043 startSmoothScroll(linearSmoothScroller); 2044 } 2045 2046 private void processPendingMovement(boolean forward) { 2047 if (forward ? hasCreatedLastItem() : hasCreatedFirstItem()) { 2048 return; 2049 } 2050 if (mPendingMoveSmoothScroller == null) { 2051 // Stop existing scroller and create a new PendingMoveSmoothScroller. 2052 mBaseGridView.stopScroll(); 2053 PendingMoveSmoothScroller linearSmoothScroller = new PendingMoveSmoothScroller( 2054 forward ? 1 : -1, mNumRows > 1); 2055 mFocusPositionOffset = 0; 2056 startSmoothScroll(linearSmoothScroller); 2057 if (linearSmoothScroller.isRunning()) { 2058 mPendingMoveSmoothScroller = linearSmoothScroller; 2059 } 2060 } else { 2061 if (forward) { 2062 mPendingMoveSmoothScroller.increasePendingMoves(); 2063 } else { 2064 mPendingMoveSmoothScroller.decreasePendingMoves(); 2065 } 2066 } 2067 } 2068 2069 @Override 2070 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 2071 if (DEBUG) Log.v(getTag(), "onItemsAdded positionStart " 2072 + positionStart + " itemCount " + itemCount); 2073 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2074 int pos = mFocusPosition + mFocusPositionOffset; 2075 if (positionStart <= pos) { 2076 mFocusPositionOffset += itemCount; 2077 } 2078 } 2079 mChildrenStates.clear(); 2080 } 2081 2082 @Override 2083 public void onItemsChanged(RecyclerView recyclerView) { 2084 if (DEBUG) Log.v(getTag(), "onItemsChanged"); 2085 mFocusPositionOffset = 0; 2086 mChildrenStates.clear(); 2087 } 2088 2089 @Override 2090 public void onItemsRemoved(RecyclerView recyclerView, int positionStart, int itemCount) { 2091 if (DEBUG) Log.v(getTag(), "onItemsRemoved positionStart " 2092 + positionStart + " itemCount " + itemCount); 2093 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2094 int pos = mFocusPosition + mFocusPositionOffset; 2095 if (positionStart <= pos) { 2096 if (positionStart + itemCount > pos) { 2097 // stop updating offset after the focus item was removed 2098 mFocusPositionOffset = Integer.MIN_VALUE; 2099 } else { 2100 mFocusPositionOffset -= itemCount; 2101 } 2102 } 2103 } 2104 mChildrenStates.clear(); 2105 } 2106 2107 @Override 2108 public void onItemsMoved(RecyclerView recyclerView, int fromPosition, int toPosition, 2109 int itemCount) { 2110 if (DEBUG) Log.v(getTag(), "onItemsMoved fromPosition " 2111 + fromPosition + " toPosition " + toPosition); 2112 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2113 int pos = mFocusPosition + mFocusPositionOffset; 2114 if (fromPosition <= pos && pos < fromPosition + itemCount) { 2115 // moved items include focused position 2116 mFocusPositionOffset += toPosition - fromPosition; 2117 } else if (fromPosition < pos && toPosition > pos - itemCount) { 2118 // move items before focus position to after focused position 2119 mFocusPositionOffset -= itemCount; 2120 } else if (fromPosition > pos && toPosition < pos) { 2121 // move items after focus position to before focused position 2122 mFocusPositionOffset += itemCount; 2123 } 2124 } 2125 mChildrenStates.clear(); 2126 } 2127 2128 @Override 2129 public void onItemsUpdated(RecyclerView recyclerView, int positionStart, int itemCount) { 2130 if (DEBUG) Log.v(getTag(), "onItemsUpdated positionStart " 2131 + positionStart + " itemCount " + itemCount); 2132 for (int i = positionStart, end = positionStart + itemCount; i < end; i++) { 2133 mChildrenStates.remove(i); 2134 } 2135 } 2136 2137 @Override 2138 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 2139 if (mFocusSearchDisabled) { 2140 return true; 2141 } 2142 if (getPositionByView(child) == NO_POSITION) { 2143 // This shouldn't happen, but in case it does be sure not to attempt a 2144 // scroll to a view whose item has been removed. 2145 return true; 2146 } 2147 if (!mInLayout && !mInSelection) { 2148 scrollToView(child, true); 2149 } 2150 return true; 2151 } 2152 2153 @Override 2154 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 2155 boolean immediate) { 2156 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 2157 return false; 2158 } 2159 2160 int getScrollOffsetX() { 2161 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 2162 } 2163 2164 int getScrollOffsetY() { 2165 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 2166 } 2167 2168 public void getViewSelectedOffsets(View view, int[] offsets) { 2169 if (mOrientation == HORIZONTAL) { 2170 offsets[0] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2171 offsets[1] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2172 } else { 2173 offsets[1] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2174 offsets[0] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2175 } 2176 } 2177 2178 private int getPrimarySystemScrollPosition(View view) { 2179 final int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 2180 final int viewMin = getViewMin(view); 2181 final int viewMax = getViewMax(view); 2182 // TODO: change to use State object in onRequestChildFocus() 2183 boolean isMin, isMax; 2184 if (!mReverseFlowPrimary) { 2185 isMin = mGrid.getFirstVisibleIndex() == 0; 2186 isMax = mGrid.getLastVisibleIndex() == (mState == null ? 2187 getItemCount() : mState.getItemCount()) - 1; 2188 } else { 2189 isMax = mGrid.getFirstVisibleIndex() == 0; 2190 isMin = mGrid.getLastVisibleIndex() == (mState == null ? 2191 getItemCount() : mState.getItemCount()) - 1; 2192 } 2193 for (int i = getChildCount() - 1; (isMin || isMax) && i >= 0; i--) { 2194 View v = getChildAt(i); 2195 if (v == view || v == null) { 2196 continue; 2197 } 2198 if (isMin && getViewMin(v) < viewMin) { 2199 isMin = false; 2200 } 2201 if (isMax && getViewMax(v) > viewMax) { 2202 isMax = false; 2203 } 2204 } 2205 return mWindowAlignment.mainAxis().getSystemScrollPos(viewCenterPrimary, isMin, isMax); 2206 } 2207 2208 private int getSecondarySystemScrollPosition(View view) { 2209 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 2210 int pos = getPositionByView(view); 2211 Grid.Location location = mGrid.getLocation(pos); 2212 final int row = location.row; 2213 final boolean isMin, isMax; 2214 if (!mReverseFlowSecondary) { 2215 isMin = row == 0; 2216 isMax = row == mGrid.getNumRows() - 1; 2217 } else { 2218 isMax = row == 0; 2219 isMin = row == mGrid.getNumRows() - 1; 2220 } 2221 return mWindowAlignment.secondAxis().getSystemScrollPos(viewCenterSecondary, isMin, isMax); 2222 } 2223 2224 /** 2225 * Scroll to a given child view and change mFocusPosition. 2226 */ 2227 private void scrollToView(View view, boolean smooth) { 2228 int newFocusPosition = getPositionByView(view); 2229 if (newFocusPosition != mFocusPosition) { 2230 mFocusPosition = newFocusPosition; 2231 mFocusPositionOffset = 0; 2232 if (!mInLayout) { 2233 dispatchChildSelected(); 2234 } 2235 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 2236 mBaseGridView.invalidate(); 2237 } 2238 } 2239 if (view == null) { 2240 return; 2241 } 2242 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 2243 // transfer focus to the child if it does not have focus yet (e.g. triggered 2244 // by setSelection()) 2245 view.requestFocus(); 2246 } 2247 if (!mScrollEnabled && smooth) { 2248 return; 2249 } 2250 if (getScrollPosition(view, sTwoInts)) { 2251 scrollGrid(sTwoInts[0], sTwoInts[1], smooth); 2252 } 2253 } 2254 2255 private boolean getScrollPosition(View view, int[] deltas) { 2256 switch (mFocusScrollStrategy) { 2257 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2258 default: 2259 return getAlignedPosition(view, deltas); 2260 case BaseGridView.FOCUS_SCROLL_ITEM: 2261 case BaseGridView.FOCUS_SCROLL_PAGE: 2262 return getNoneAlignedPosition(view, deltas); 2263 } 2264 } 2265 2266 private boolean getNoneAlignedPosition(View view, int[] deltas) { 2267 int pos = getPositionByView(view); 2268 int viewMin = getViewMin(view); 2269 int viewMax = getViewMax(view); 2270 // we either align "firstView" to left/top padding edge 2271 // or align "lastView" to right/bottom padding edge 2272 View firstView = null; 2273 View lastView = null; 2274 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 2275 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 2276 final int row = mGrid.getRowIndex(pos); 2277 if (viewMin < paddingLow) { 2278 // view enters low padding area: 2279 firstView = view; 2280 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2281 // scroll one "page" left/top, 2282 // align first visible item of the "page" at the low padding edge. 2283 while (prependOneColumnVisibleItems()) { 2284 CircularIntArray positions = 2285 mGrid.getItemPositionsInRows(mGrid.getFirstVisibleIndex(), pos)[row]; 2286 firstView = findViewByPosition(positions.get(0)); 2287 if (viewMax - getViewMin(firstView) > clientSize) { 2288 if (positions.size() > 2) { 2289 firstView = findViewByPosition(positions.get(2)); 2290 } 2291 break; 2292 } 2293 } 2294 } 2295 } else if (viewMax > clientSize + paddingLow) { 2296 // view enters high padding area: 2297 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2298 // scroll whole one page right/bottom, align view at the low padding edge. 2299 firstView = view; 2300 do { 2301 CircularIntArray positions = 2302 mGrid.getItemPositionsInRows(pos, mGrid.getLastVisibleIndex())[row]; 2303 lastView = findViewByPosition(positions.get(positions.size() - 1)); 2304 if (getViewMax(lastView) - viewMin > clientSize) { 2305 lastView = null; 2306 break; 2307 } 2308 } while (appendOneColumnVisibleItems()); 2309 if (lastView != null) { 2310 // however if we reached end, we should align last view. 2311 firstView = null; 2312 } 2313 } else { 2314 lastView = view; 2315 } 2316 } 2317 int scrollPrimary = 0; 2318 int scrollSecondary = 0; 2319 if (firstView != null) { 2320 scrollPrimary = getViewMin(firstView) - paddingLow; 2321 } else if (lastView != null) { 2322 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 2323 } 2324 View secondaryAlignedView; 2325 if (firstView != null) { 2326 secondaryAlignedView = firstView; 2327 } else if (lastView != null) { 2328 secondaryAlignedView = lastView; 2329 } else { 2330 secondaryAlignedView = view; 2331 } 2332 scrollSecondary = getSecondarySystemScrollPosition(secondaryAlignedView); 2333 scrollSecondary -= mScrollOffsetSecondary; 2334 if (scrollPrimary != 0 || scrollSecondary != 0) { 2335 deltas[0] = scrollPrimary; 2336 deltas[1] = scrollSecondary; 2337 return true; 2338 } 2339 return false; 2340 } 2341 2342 private boolean getAlignedPosition(View view, int[] deltas) { 2343 int scrollPrimary = getPrimarySystemScrollPosition(view); 2344 int scrollSecondary = getSecondarySystemScrollPosition(view); 2345 if (DEBUG) { 2346 Log.v(getTag(), "getAlignedPosition " + scrollPrimary + " " + scrollSecondary 2347 + " " + mPrimaryScrollExtra + " " + mWindowAlignment); 2348 Log.v(getTag(), "getAlignedPosition " + mScrollOffsetPrimary + " " + mScrollOffsetSecondary); 2349 } 2350 scrollPrimary -= mScrollOffsetPrimary; 2351 scrollSecondary -= mScrollOffsetSecondary; 2352 scrollPrimary += mPrimaryScrollExtra; 2353 if (scrollPrimary != 0 || scrollSecondary != 0) { 2354 deltas[0] = scrollPrimary; 2355 deltas[1] = scrollSecondary; 2356 return true; 2357 } 2358 return false; 2359 } 2360 2361 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 2362 if (mInLayout) { 2363 scrollDirectionPrimary(scrollPrimary); 2364 scrollDirectionSecondary(scrollSecondary); 2365 } else { 2366 int scrollX; 2367 int scrollY; 2368 if (mOrientation == HORIZONTAL) { 2369 scrollX = scrollPrimary; 2370 scrollY = scrollSecondary; 2371 } else { 2372 scrollX = scrollSecondary; 2373 scrollY = scrollPrimary; 2374 } 2375 if (smooth) { 2376 mBaseGridView.smoothScrollBy(scrollX, scrollY); 2377 } else { 2378 mBaseGridView.scrollBy(scrollX, scrollY); 2379 } 2380 } 2381 } 2382 2383 public void setPruneChild(boolean pruneChild) { 2384 if (mPruneChild != pruneChild) { 2385 mPruneChild = pruneChild; 2386 if (mPruneChild) { 2387 requestLayout(); 2388 } 2389 } 2390 } 2391 2392 public boolean getPruneChild() { 2393 return mPruneChild; 2394 } 2395 2396 public void setScrollEnabled(boolean scrollEnabled) { 2397 if (mScrollEnabled != scrollEnabled) { 2398 mScrollEnabled = scrollEnabled; 2399 if (mScrollEnabled && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED 2400 && mFocusPosition != NO_POSITION) { 2401 scrollToSelection(mBaseGridView, mFocusPosition, true, mPrimaryScrollExtra); 2402 } 2403 } 2404 } 2405 2406 public boolean isScrollEnabled() { 2407 return mScrollEnabled; 2408 } 2409 2410 private int findImmediateChildIndex(View view) { 2411 while (view != null && view != mBaseGridView) { 2412 int index = mBaseGridView.indexOfChild(view); 2413 if (index >= 0) { 2414 return index; 2415 } 2416 view = (View) view.getParent(); 2417 } 2418 return NO_POSITION; 2419 } 2420 2421 void setFocusSearchDisabled(boolean disabled) { 2422 mFocusSearchDisabled = disabled; 2423 } 2424 2425 boolean isFocusSearchDisabled() { 2426 return mFocusSearchDisabled; 2427 } 2428 2429 @Override 2430 public View onInterceptFocusSearch(View focused, int direction) { 2431 if (mFocusSearchDisabled) { 2432 return focused; 2433 } 2434 return null; 2435 } 2436 2437 boolean hasPreviousViewInSameRow(int pos) { 2438 if (mGrid == null || pos == NO_POSITION || mGrid.getFirstVisibleIndex() < 0) { 2439 return false; 2440 } 2441 if (mGrid.getFirstVisibleIndex() > 0) { 2442 return true; 2443 } 2444 final int focusedRow = mGrid.getLocation(pos).row; 2445 for (int i = getChildCount() - 1; i >= 0; i--) { 2446 int position = getPositionByIndex(i); 2447 Grid.Location loc = mGrid.getLocation(position); 2448 if (loc != null && loc.row == focusedRow) { 2449 if (position < pos) { 2450 return true; 2451 } 2452 } 2453 } 2454 return false; 2455 } 2456 2457 @Override 2458 public boolean onAddFocusables(RecyclerView recyclerView, 2459 ArrayList<View> views, int direction, int focusableMode) { 2460 if (mFocusSearchDisabled) { 2461 return true; 2462 } 2463 // If this viewgroup or one of its children currently has focus then we 2464 // consider our children for focus searching in main direction on the same row. 2465 // If this viewgroup has no focus and using focus align, we want the system 2466 // to ignore our children and pass focus to the viewgroup, which will pass 2467 // focus on to its children appropriately. 2468 // If this viewgroup has no focus and not using focus align, we want to 2469 // consider the child that does not overlap with padding area. 2470 if (recyclerView.hasFocus()) { 2471 final int movement = getMovement(direction); 2472 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2473 // Move on secondary direction uses default addFocusables(). 2474 return false; 2475 } 2476 if (mPendingMoveSmoothScroller != null) { 2477 // don't find next focusable if has pending movement. 2478 return true; 2479 } 2480 final View focused = recyclerView.findFocus(); 2481 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2482 // Add focusables of focused item. 2483 if (focusedPos != NO_POSITION) { 2484 findViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2485 } 2486 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2487 mGrid.getLocation(focusedPos).row : NO_POSITION; 2488 // Add focusables of next neighbor of same row on the focus search direction. 2489 if (mGrid != null) { 2490 final int focusableCount = views.size(); 2491 for (int i = 0, count = getChildCount(); i < count; i++) { 2492 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2493 final View child = getChildAt(index); 2494 if (child.getVisibility() != View.VISIBLE || !child.hasFocusable()) { 2495 continue; 2496 } 2497 int position = getPositionByIndex(index); 2498 Grid.Location loc = mGrid.getLocation(position); 2499 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2500 if (focusedPos == NO_POSITION || 2501 (movement == NEXT_ITEM && position > focusedPos) 2502 || (movement == PREV_ITEM && position < focusedPos)) { 2503 child.addFocusables(views, direction, focusableMode); 2504 if (views.size() > focusableCount) { 2505 break; 2506 } 2507 } 2508 } 2509 } 2510 } 2511 } else { 2512 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2513 // adding views not overlapping padding area to avoid scrolling in gaining focus 2514 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2515 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2516 int focusableCount = views.size(); 2517 for (int i = 0, count = getChildCount(); i < count; i++) { 2518 View child = getChildAt(i); 2519 if (child.getVisibility() == View.VISIBLE) { 2520 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2521 child.addFocusables(views, direction, focusableMode); 2522 } 2523 } 2524 } 2525 // if we cannot find any, then just add all children. 2526 if (views.size() == focusableCount) { 2527 for (int i = 0, count = getChildCount(); i < count; i++) { 2528 View child = getChildAt(i); 2529 if (child.getVisibility() == View.VISIBLE) { 2530 child.addFocusables(views, direction, focusableMode); 2531 } 2532 } 2533 if (views.size() != focusableCount) { 2534 return true; 2535 } 2536 } else { 2537 return true; 2538 } 2539 // if still cannot find any, fall through and add itself 2540 } 2541 if (recyclerView.isFocusable()) { 2542 views.add(recyclerView); 2543 } 2544 } 2545 return true; 2546 } 2547 2548 private boolean hasCreatedLastItem() { 2549 int count = mState.getItemCount(); 2550 return count == 0 || findViewByPosition(count - 1) != null; 2551 } 2552 2553 private boolean hasCreatedFirstItem() { 2554 int count = mState.getItemCount(); 2555 return count == 0 || findViewByPosition(0) != null; 2556 } 2557 2558 boolean canScrollTo(View view) { 2559 return view.getVisibility() == View.VISIBLE && (!hasFocus() || view.hasFocusable()); 2560 } 2561 2562 @Override 2563 public View onFocusSearchFailed(View focused, int direction, Recycler recycler, 2564 RecyclerView.State state) { 2565 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2566 2567 View view = null; 2568 int movement = getMovement(direction); 2569 final boolean isScroll = mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE; 2570 saveContext(recycler, state); 2571 if (movement == NEXT_ITEM) { 2572 if (isScroll || !mFocusOutEnd) { 2573 view = focused; 2574 } 2575 if (mScrollEnabled && !hasCreatedLastItem()) { 2576 processPendingMovement(true); 2577 view = focused; 2578 } 2579 } else if (movement == PREV_ITEM) { 2580 if (isScroll || !mFocusOutFront) { 2581 view = focused; 2582 } 2583 if (mScrollEnabled && !hasCreatedFirstItem()) { 2584 processPendingMovement(false); 2585 view = focused; 2586 } 2587 } 2588 leaveContext(); 2589 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed returning view " + view); 2590 return view; 2591 } 2592 2593 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2594 Rect previouslyFocusedRect) { 2595 switch (mFocusScrollStrategy) { 2596 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2597 default: 2598 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2599 direction, previouslyFocusedRect); 2600 case BaseGridView.FOCUS_SCROLL_PAGE: 2601 case BaseGridView.FOCUS_SCROLL_ITEM: 2602 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2603 direction, previouslyFocusedRect); 2604 } 2605 } 2606 2607 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2608 int direction, Rect previouslyFocusedRect) { 2609 View view = findViewByPosition(mFocusPosition); 2610 if (view != null) { 2611 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2612 if (!result && DEBUG) { 2613 Log.w(getTag(), "failed to request focus on " + view); 2614 } 2615 return result; 2616 } 2617 return false; 2618 } 2619 2620 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2621 int direction, Rect previouslyFocusedRect) { 2622 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2623 int index; 2624 int increment; 2625 int end; 2626 int count = getChildCount(); 2627 if ((direction & View.FOCUS_FORWARD) != 0) { 2628 index = 0; 2629 increment = 1; 2630 end = count; 2631 } else { 2632 index = count - 1; 2633 increment = -1; 2634 end = -1; 2635 } 2636 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2637 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2638 for (int i = index; i != end; i += increment) { 2639 View child = getChildAt(i); 2640 if (child.getVisibility() == View.VISIBLE) { 2641 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2642 if (child.requestFocus(direction, previouslyFocusedRect)) { 2643 return true; 2644 } 2645 } 2646 } 2647 } 2648 return false; 2649 } 2650 2651 private final static int PREV_ITEM = 0; 2652 private final static int NEXT_ITEM = 1; 2653 private final static int PREV_ROW = 2; 2654 private final static int NEXT_ROW = 3; 2655 2656 private int getMovement(int direction) { 2657 int movement = View.FOCUS_LEFT; 2658 2659 if (mOrientation == HORIZONTAL) { 2660 switch(direction) { 2661 case View.FOCUS_LEFT: 2662 movement = (!mReverseFlowPrimary) ? PREV_ITEM : NEXT_ITEM; 2663 break; 2664 case View.FOCUS_RIGHT: 2665 movement = (!mReverseFlowPrimary) ? NEXT_ITEM : PREV_ITEM; 2666 break; 2667 case View.FOCUS_UP: 2668 movement = PREV_ROW; 2669 break; 2670 case View.FOCUS_DOWN: 2671 movement = NEXT_ROW; 2672 break; 2673 } 2674 } else if (mOrientation == VERTICAL) { 2675 switch(direction) { 2676 case View.FOCUS_LEFT: 2677 movement = (!mReverseFlowPrimary) ? PREV_ROW : NEXT_ROW; 2678 break; 2679 case View.FOCUS_RIGHT: 2680 movement = (!mReverseFlowPrimary) ? NEXT_ROW : PREV_ROW; 2681 break; 2682 case View.FOCUS_UP: 2683 movement = PREV_ITEM; 2684 break; 2685 case View.FOCUS_DOWN: 2686 movement = NEXT_ITEM; 2687 break; 2688 } 2689 } 2690 2691 return movement; 2692 } 2693 2694 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2695 View view = findViewByPosition(mFocusPosition); 2696 if (view == null) { 2697 return i; 2698 } 2699 int focusIndex = recyclerView.indexOfChild(view); 2700 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2701 // drawing order is 0 1 2 3 9 8 7 6 5 4 2702 if (i < focusIndex) { 2703 return i; 2704 } else if (i < childCount - 1) { 2705 return focusIndex + childCount - 1 - i; 2706 } else { 2707 return focusIndex; 2708 } 2709 } 2710 2711 @Override 2712 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2713 RecyclerView.Adapter newAdapter) { 2714 if (DEBUG) Log.v(getTag(), "onAdapterChanged to " + newAdapter); 2715 if (oldAdapter != null) { 2716 discardLayoutInfo(); 2717 mFocusPosition = NO_POSITION; 2718 mFocusPositionOffset = 0; 2719 mChildrenStates.clear(); 2720 } 2721 super.onAdapterChanged(oldAdapter, newAdapter); 2722 } 2723 2724 private void discardLayoutInfo() { 2725 mGrid = null; 2726 mRowSizeSecondary = null; 2727 mRowSecondarySizeRefresh = false; 2728 } 2729 2730 public void setLayoutEnabled(boolean layoutEnabled) { 2731 if (mLayoutEnabled != layoutEnabled) { 2732 mLayoutEnabled = layoutEnabled; 2733 requestLayout(); 2734 } 2735 } 2736 2737 void setChildrenVisibility(int visiblity) { 2738 mChildVisibility = visiblity; 2739 if (mChildVisibility != -1) { 2740 int count = getChildCount(); 2741 for (int i= 0; i < count; i++) { 2742 getChildAt(i).setVisibility(mChildVisibility); 2743 } 2744 } 2745 } 2746 2747 final static class SavedState implements Parcelable { 2748 2749 int index; // index inside adapter of the current view 2750 Bundle childStates = Bundle.EMPTY; 2751 2752 @Override 2753 public void writeToParcel(Parcel out, int flags) { 2754 out.writeInt(index); 2755 out.writeBundle(childStates); 2756 } 2757 2758 @SuppressWarnings("hiding") 2759 public static final Parcelable.Creator<SavedState> CREATOR = 2760 new Parcelable.Creator<SavedState>() { 2761 @Override 2762 public SavedState createFromParcel(Parcel in) { 2763 return new SavedState(in); 2764 } 2765 2766 @Override 2767 public SavedState[] newArray(int size) { 2768 return new SavedState[size]; 2769 } 2770 }; 2771 2772 @Override 2773 public int describeContents() { 2774 return 0; 2775 } 2776 2777 SavedState(Parcel in) { 2778 index = in.readInt(); 2779 childStates = in.readBundle(GridLayoutManager.class.getClassLoader()); 2780 } 2781 2782 SavedState() { 2783 } 2784 } 2785 2786 @Override 2787 public Parcelable onSaveInstanceState() { 2788 if (DEBUG) Log.v(getTag(), "onSaveInstanceState getSelection() " + getSelection()); 2789 SavedState ss = new SavedState(); 2790 for (int i = 0, count = getChildCount(); i < count; i++) { 2791 View view = getChildAt(i); 2792 int position = getPositionByView(view); 2793 if (position != NO_POSITION) { 2794 mChildrenStates.saveOnScreenView(view, position); 2795 } 2796 } 2797 ss.index = getSelection(); 2798 ss.childStates = mChildrenStates.saveAsBundle(); 2799 return ss; 2800 } 2801 2802 void onChildRecycled(RecyclerView.ViewHolder holder) { 2803 final int position = holder.getAdapterPosition(); 2804 if (position != NO_POSITION) { 2805 mChildrenStates.saveOffscreenView(holder.itemView, position); 2806 } 2807 } 2808 2809 @Override 2810 public void onRestoreInstanceState(Parcelable state) { 2811 if (!(state instanceof SavedState)) { 2812 return; 2813 } 2814 SavedState loadingState = (SavedState)state; 2815 mFocusPosition = loadingState.index; 2816 mFocusPositionOffset = 0; 2817 mChildrenStates.loadFromBundle(loadingState.childStates); 2818 mForceFullLayout = true; 2819 requestLayout(); 2820 if (DEBUG) Log.v(getTag(), "onRestoreInstanceState mFocusPosition " + mFocusPosition); 2821 } 2822} 2823