GridLayoutManager.java revision 6b22c4c875d7a540e705b2b6b65bf52c7a89299a
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 } 328 if (mPendingMoves == 0 || (mPendingMoves > 0 && hasCreatedLastItem()) 329 || (mPendingMoves < 0 && hasCreatedFirstItem())) { 330 setTargetPosition(mFocusPosition); 331 stop(); 332 } 333 } 334 335 @Override 336 protected void updateActionForInterimTarget(Action action) { 337 if (mPendingMoves == 0) { 338 return; 339 } 340 super.updateActionForInterimTarget(action); 341 } 342 343 @Override 344 public PointF computeScrollVectorForPosition(int targetPosition) { 345 if (mPendingMoves == 0) { 346 return null; 347 } 348 int direction = (mReverseFlowPrimary ? mPendingMoves > 0 : mPendingMoves < 0) ? 349 -1 : 1; 350 if (mOrientation == HORIZONTAL) { 351 return new PointF(direction, 0); 352 } else { 353 return new PointF(0, direction); 354 } 355 } 356 357 @Override 358 boolean needsDispatchChildSelectedOnStop() { 359 return mPendingMoves != 0; 360 } 361 362 @Override 363 protected void onStop() { 364 super.onStop(); 365 // if we hit wall, need clear the remaining pending moves. 366 mPendingMoves = 0; 367 mPendingMoveSmoothScroller = null; 368 View v = findViewByPosition(getTargetPosition()); 369 if (v != null) scrollToView(v, true); 370 } 371 }; 372 373 private static final String TAG = "GridLayoutManager"; 374 private static final boolean DEBUG = false; 375 private static final boolean TRACE = false; 376 377 // maximum pending movement in one direction. 378 private final static int MAX_PENDING_MOVES = 10; 379 380 private String getTag() { 381 return TAG + ":" + mBaseGridView.getId(); 382 } 383 384 private final BaseGridView mBaseGridView; 385 386 /** 387 * Note on conventions in the presence of RTL layout directions: 388 * Many properties and method names reference entities related to the 389 * beginnings and ends of things. In the presence of RTL flows, 390 * it may not be clear whether this is intended to reference a 391 * quantity that changes direction in RTL cases, or a quantity that 392 * does not. Here are the conventions in use: 393 * 394 * start/end: coordinate quantities - do reverse 395 * (optical) left/right: coordinate quantities - do not reverse 396 * low/high: coordinate quantities - do not reverse 397 * min/max: coordinate quantities - do not reverse 398 * scroll offset - coordinate quantities - do not reverse 399 * first/last: positional indices - do not reverse 400 * front/end: positional indices - do not reverse 401 * prepend/append: related to positional indices - do not reverse 402 * 403 * Note that although quantities do not reverse in RTL flows, their 404 * relationship does. In LTR flows, the first positional index is 405 * leftmost; in RTL flows, it is rightmost. Thus, anywhere that 406 * positional quantities are mapped onto coordinate quantities, 407 * the flow must be checked and the logic reversed. 408 */ 409 410 /** 411 * The orientation of a "row". 412 */ 413 private int mOrientation = HORIZONTAL; 414 415 private RecyclerView.State mState; 416 private RecyclerView.Recycler mRecycler; 417 418 private boolean mInLayout = false; 419 private boolean mInFastRelayout; 420 /** 421 * During full layout pass, when GridView had focus: onLayoutChildren will 422 * skip non-focusable child and adjust mFocusPosition. 423 */ 424 private boolean mInLayoutSearchFocus; 425 private boolean mInSelection = false; 426 427 private OnChildSelectedListener mChildSelectedListener = null; 428 429 private OnChildLaidOutListener mChildLaidOutListener = null; 430 431 /** 432 * The focused position, it's not the currently visually aligned position 433 * but it is the final position that we intend to focus on. If there are 434 * multiple setSelection() called, mFocusPosition saves last value. 435 */ 436 private int mFocusPosition = NO_POSITION; 437 438 /** 439 * LinearSmoothScroller that consume pending DPAD movements. 440 */ 441 private PendingMoveSmoothScroller mPendingMoveSmoothScroller; 442 443 /** 444 * The offset to be applied to mFocusPosition, due to adapter change, on the next 445 * layout. Set to Integer.MIN_VALUE means item was removed. 446 * TODO: This is somewhat duplication of RecyclerView getOldPosition() which is 447 * unfortunately cleared after prelayout. 448 */ 449 private int mFocusPositionOffset = 0; 450 451 /** 452 * Force a full layout under certain situations. E.g. Rows change, jump to invisible child. 453 */ 454 private boolean mForceFullLayout; 455 456 /** 457 * True if layout is enabled. 458 */ 459 private boolean mLayoutEnabled = true; 460 461 /** 462 * override child visibility 463 */ 464 private int mChildVisibility = -1; 465 466 /** 467 * The scroll offsets of the viewport relative to the entire view. 468 */ 469 private int mScrollOffsetPrimary; 470 private int mScrollOffsetSecondary; 471 472 /** 473 * User-specified row height/column width. Can be WRAP_CONTENT. 474 */ 475 private int mRowSizeSecondaryRequested; 476 477 /** 478 * The fixed size of each grid item in the secondary direction. This corresponds to 479 * the row height, equal for all rows. Grid items may have variable length 480 * in the primary direction. 481 */ 482 private int mFixedRowSizeSecondary; 483 484 /** 485 * Tracks the secondary size of each row. 486 */ 487 private int[] mRowSizeSecondary; 488 489 /** 490 * Flag controlling whether the current/next layout should 491 * be updating the secondary size of rows. 492 */ 493 private boolean mRowSecondarySizeRefresh; 494 495 /** 496 * The maximum measured size of the view. 497 */ 498 private int mMaxSizeSecondary; 499 500 /** 501 * Margin between items. 502 */ 503 private int mHorizontalMargin; 504 /** 505 * Margin between items vertically. 506 */ 507 private int mVerticalMargin; 508 /** 509 * Margin in main direction. 510 */ 511 private int mMarginPrimary; 512 /** 513 * Margin in second direction. 514 */ 515 private int mMarginSecondary; 516 /** 517 * How to position child in secondary direction. 518 */ 519 private int mGravity = Gravity.START | Gravity.TOP; 520 /** 521 * The number of rows in the grid. 522 */ 523 private int mNumRows; 524 /** 525 * Number of rows requested, can be 0 to be determined by parent size and 526 * rowHeight. 527 */ 528 private int mNumRowsRequested = 1; 529 530 /** 531 * Saves grid information of each view. 532 */ 533 Grid mGrid; 534 535 /** 536 * Focus Scroll strategy. 537 */ 538 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 539 /** 540 * Defines how item view is aligned in the window. 541 */ 542 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 543 544 /** 545 * Defines how item view is aligned. 546 */ 547 private final ItemAlignment mItemAlignment = new ItemAlignment(); 548 549 /** 550 * Dimensions of the view, width or height depending on orientation. 551 */ 552 private int mSizePrimary; 553 554 /** 555 * Allow DPAD key to navigate out at the front of the View (where position = 0), 556 * default is false. 557 */ 558 private boolean mFocusOutFront; 559 560 /** 561 * Allow DPAD key to navigate out at the end of the view, default is false. 562 */ 563 private boolean mFocusOutEnd; 564 565 /** 566 * True if focus search is disabled. 567 */ 568 private boolean mFocusSearchDisabled; 569 570 /** 571 * True if prune child, might be disabled during transition. 572 */ 573 private boolean mPruneChild = true; 574 575 /** 576 * True if scroll content, might be disabled during transition. 577 */ 578 private boolean mScrollEnabled = true; 579 580 /** 581 * Temporary variable: an int array of length=2. 582 */ 583 private static int[] sTwoInts = new int[2]; 584 585 /** 586 * Set to true for RTL layout in horizontal orientation 587 */ 588 private boolean mReverseFlowPrimary = false; 589 590 /** 591 * Set to true for RTL layout in vertical orientation 592 */ 593 private boolean mReverseFlowSecondary = false; 594 595 /** 596 * Temporaries used for measuring. 597 */ 598 private int[] mMeasuredDimension = new int[2]; 599 600 final ViewsStateBundle mChildrenStates = new ViewsStateBundle(); 601 602 public GridLayoutManager(BaseGridView baseGridView) { 603 mBaseGridView = baseGridView; 604 } 605 606 public void setOrientation(int orientation) { 607 if (orientation != HORIZONTAL && orientation != VERTICAL) { 608 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 609 return; 610 } 611 612 mOrientation = orientation; 613 mWindowAlignment.setOrientation(orientation); 614 mItemAlignment.setOrientation(orientation); 615 mForceFullLayout = true; 616 } 617 618 public void onRtlPropertiesChanged(int layoutDirection) { 619 if (mOrientation == HORIZONTAL) { 620 mReverseFlowPrimary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 621 mReverseFlowSecondary = false; 622 } else { 623 mReverseFlowSecondary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 624 mReverseFlowPrimary = false; 625 } 626 mWindowAlignment.horizontal.setReversedFlow(layoutDirection == View.LAYOUT_DIRECTION_RTL); 627 } 628 629 public int getFocusScrollStrategy() { 630 return mFocusScrollStrategy; 631 } 632 633 public void setFocusScrollStrategy(int focusScrollStrategy) { 634 mFocusScrollStrategy = focusScrollStrategy; 635 } 636 637 public void setWindowAlignment(int windowAlignment) { 638 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 639 } 640 641 public int getWindowAlignment() { 642 return mWindowAlignment.mainAxis().getWindowAlignment(); 643 } 644 645 public void setWindowAlignmentOffset(int alignmentOffset) { 646 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 647 } 648 649 public int getWindowAlignmentOffset() { 650 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 651 } 652 653 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 654 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 655 } 656 657 public float getWindowAlignmentOffsetPercent() { 658 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 659 } 660 661 public void setItemAlignmentOffset(int alignmentOffset) { 662 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 663 updateChildAlignments(); 664 } 665 666 public int getItemAlignmentOffset() { 667 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 668 } 669 670 public void setItemAlignmentOffsetWithPadding(boolean withPadding) { 671 mItemAlignment.mainAxis().setItemAlignmentOffsetWithPadding(withPadding); 672 updateChildAlignments(); 673 } 674 675 public boolean isItemAlignmentOffsetWithPadding() { 676 return mItemAlignment.mainAxis().isItemAlignmentOffsetWithPadding(); 677 } 678 679 public void setItemAlignmentOffsetPercent(float offsetPercent) { 680 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 681 updateChildAlignments(); 682 } 683 684 public float getItemAlignmentOffsetPercent() { 685 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 686 } 687 688 public void setItemAlignmentViewId(int viewId) { 689 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 690 updateChildAlignments(); 691 } 692 693 public int getItemAlignmentViewId() { 694 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 695 } 696 697 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 698 mFocusOutFront = throughFront; 699 mFocusOutEnd = throughEnd; 700 } 701 702 public void setNumRows(int numRows) { 703 if (numRows < 0) throw new IllegalArgumentException(); 704 mNumRowsRequested = numRows; 705 mForceFullLayout = true; 706 } 707 708 /** 709 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 710 */ 711 public void setRowHeight(int height) { 712 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 713 mRowSizeSecondaryRequested = height; 714 } else { 715 throw new IllegalArgumentException("Invalid row height: " + height); 716 } 717 } 718 719 public void setItemMargin(int margin) { 720 mVerticalMargin = mHorizontalMargin = margin; 721 mMarginPrimary = mMarginSecondary = margin; 722 } 723 724 public void setVerticalMargin(int margin) { 725 if (mOrientation == HORIZONTAL) { 726 mMarginSecondary = mVerticalMargin = margin; 727 } else { 728 mMarginPrimary = mVerticalMargin = margin; 729 } 730 } 731 732 public void setHorizontalMargin(int margin) { 733 if (mOrientation == HORIZONTAL) { 734 mMarginPrimary = mHorizontalMargin = margin; 735 } else { 736 mMarginSecondary = mHorizontalMargin = margin; 737 } 738 } 739 740 public int getVerticalMargin() { 741 return mVerticalMargin; 742 } 743 744 public int getHorizontalMargin() { 745 return mHorizontalMargin; 746 } 747 748 public void setGravity(int gravity) { 749 mGravity = gravity; 750 } 751 752 protected boolean hasDoneFirstLayout() { 753 return mGrid != null; 754 } 755 756 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 757 mChildSelectedListener = listener; 758 } 759 760 void setOnChildLaidOutListener(OnChildLaidOutListener listener) { 761 mChildLaidOutListener = listener; 762 } 763 764 private int getPositionByView(View view) { 765 if (view == null) { 766 return NO_POSITION; 767 } 768 LayoutParams params = (LayoutParams) view.getLayoutParams(); 769 if (params == null || params.isItemRemoved()) { 770 // when item is removed, the position value can be any value. 771 return NO_POSITION; 772 } 773 return params.getViewPosition(); 774 } 775 776 private int getPositionByIndex(int index) { 777 return getPositionByView(getChildAt(index)); 778 } 779 780 private void dispatchChildSelected() { 781 if (mChildSelectedListener == null) { 782 return; 783 } 784 785 if (TRACE) TraceHelper.beginSection("onChildSelected"); 786 View view = mFocusPosition == NO_POSITION ? null : findViewByPosition(mFocusPosition); 787 if (view != null) { 788 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(view); 789 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 790 vh == null? NO_ID: vh.getItemId()); 791 } else { 792 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 793 } 794 if (TRACE) TraceHelper.endSection(); 795 796 // Children may request layout when a child selection event occurs (such as a change of 797 // padding on the current and previously selected rows). 798 // If in layout, a child requesting layout may have been laid out before the selection 799 // callback. 800 // If it was not, the child will be laid out after the selection callback. 801 // If so, the layout request will be honoured though the view system will emit a double- 802 // layout warning. 803 // If not in layout, we may be scrolling in which case the child layout request will be 804 // eaten by recyclerview. Post a requestLayout. 805 if (!mInLayout && !mBaseGridView.isLayoutRequested()) { 806 int childCount = getChildCount(); 807 for (int i = 0; i < childCount; i++) { 808 if (getChildAt(i).isLayoutRequested()) { 809 forceRequestLayout(); 810 break; 811 } 812 } 813 } 814 } 815 816 @Override 817 public boolean canScrollHorizontally() { 818 // We can scroll horizontally if we have horizontal orientation, or if 819 // we are vertical and have more than one column. 820 return mOrientation == HORIZONTAL || mNumRows > 1; 821 } 822 823 @Override 824 public boolean canScrollVertically() { 825 // We can scroll vertically if we have vertical orientation, or if we 826 // are horizontal and have more than one row. 827 return mOrientation == VERTICAL || mNumRows > 1; 828 } 829 830 @Override 831 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 832 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 833 ViewGroup.LayoutParams.WRAP_CONTENT); 834 } 835 836 @Override 837 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 838 return new LayoutParams(context, attrs); 839 } 840 841 @Override 842 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 843 if (lp instanceof LayoutParams) { 844 return new LayoutParams((LayoutParams) lp); 845 } else if (lp instanceof RecyclerView.LayoutParams) { 846 return new LayoutParams((RecyclerView.LayoutParams) lp); 847 } else if (lp instanceof MarginLayoutParams) { 848 return new LayoutParams((MarginLayoutParams) lp); 849 } else { 850 return new LayoutParams(lp); 851 } 852 } 853 854 protected View getViewForPosition(int position) { 855 return mRecycler.getViewForPosition(position); 856 } 857 858 final int getOpticalLeft(View v) { 859 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 860 } 861 862 final int getOpticalRight(View v) { 863 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 864 } 865 866 final int getOpticalTop(View v) { 867 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 868 } 869 870 final int getOpticalBottom(View v) { 871 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 872 } 873 874 private int getViewMin(View v) { 875 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 876 } 877 878 private int getViewMax(View v) { 879 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 880 } 881 882 private int getViewCenter(View view) { 883 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 884 } 885 886 private int getViewCenterSecondary(View view) { 887 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 888 } 889 890 private int getViewCenterX(View v) { 891 LayoutParams p = (LayoutParams) v.getLayoutParams(); 892 return p.getOpticalLeft(v) + p.getAlignX(); 893 } 894 895 private int getViewCenterY(View v) { 896 LayoutParams p = (LayoutParams) v.getLayoutParams(); 897 return p.getOpticalTop(v) + p.getAlignY(); 898 } 899 900 /** 901 * Save Recycler and State for convenience. Must be paired with leaveContext(). 902 */ 903 private void saveContext(Recycler recycler, State state) { 904 if (mRecycler != null || mState != null) { 905 Log.e(TAG, "Recycler information was not released, bug!"); 906 } 907 mRecycler = recycler; 908 mState = state; 909 } 910 911 /** 912 * Discard saved Recycler and State. 913 */ 914 private void leaveContext() { 915 mRecycler = null; 916 mState = null; 917 } 918 919 /** 920 * Re-initialize data structures for a data change or handling invisible 921 * selection. The method tries its best to preserve position information so 922 * that staggered grid looks same before and after re-initialize. 923 * @return true if can fastRelayout() 924 */ 925 private boolean layoutInit() { 926 if (!mState.didStructureChange() && !mForceFullLayout && mGrid != null) { 927 updateScrollController(); 928 updateScrollSecondAxis(); 929 mGrid.setMargin(mMarginPrimary); 930 return true; 931 } else { 932 mForceFullLayout = false; 933 boolean focusViewWasInTree = mGrid != null && mFocusPosition >= 0 934 && mFocusPosition >= mGrid.getFirstVisibleIndex() 935 && mFocusPosition <= mGrid.getLastVisibleIndex(); 936 int firstVisibleIndex = focusViewWasInTree ? mGrid.getFirstVisibleIndex() : 0; 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 } 946 947 if (mGrid == null || mNumRows != mGrid.getNumRows() || 948 mReverseFlowPrimary != mGrid.isReversedFlow()) { 949 mGrid = Grid.createStaggeredMultipleRows(mNumRows); 950 mGrid.setProvider(mGridProvider); 951 mGrid.setReversedFlow(mReverseFlowPrimary); 952 } 953 initScrollController(); 954 updateScrollSecondAxis(); 955 mGrid.setMargin(mMarginPrimary); 956 detachAndScrapAttachedViews(mRecycler); 957 mGrid.resetVisibleIndex(); 958 if (mFocusPosition == NO_POSITION) { 959 mBaseGridView.clearFocus(); 960 } 961 mWindowAlignment.mainAxis().invalidateScrollMin(); 962 mWindowAlignment.mainAxis().invalidateScrollMax(); 963 if (focusViewWasInTree && firstVisibleIndex <= mFocusPosition) { 964 // if focusView was in tree, we will add item from first visible item 965 mGrid.setStart(firstVisibleIndex); 966 } else { 967 // if focusView was not in tree, it's probably because focus position jumped 968 // far away from visible range, so use mFocusPosition as start 969 mGrid.setStart(mFocusPosition); 970 } 971 return false; 972 } 973 } 974 975 private int getRowSizeSecondary(int rowIndex) { 976 if (mFixedRowSizeSecondary != 0) { 977 return mFixedRowSizeSecondary; 978 } 979 if (mRowSizeSecondary == null) { 980 return 0; 981 } 982 return mRowSizeSecondary[rowIndex]; 983 } 984 985 private int getRowStartSecondary(int rowIndex) { 986 int start = 0; 987 // Iterate from left to right, which is a different index traversal 988 // in RTL flow 989 if (mReverseFlowSecondary) { 990 for (int i = mNumRows-1; i > rowIndex; i--) { 991 start += getRowSizeSecondary(i) + mMarginSecondary; 992 } 993 } else { 994 for (int i = 0; i < rowIndex; i++) { 995 start += getRowSizeSecondary(i) + mMarginSecondary; 996 } 997 } 998 return start; 999 } 1000 1001 private int getSizeSecondary() { 1002 int rightmostIndex = mReverseFlowSecondary ? 0 : mNumRows - 1; 1003 return getRowStartSecondary(rightmostIndex) + getRowSizeSecondary(rightmostIndex); 1004 } 1005 1006 private void measureScrapChild(int position, int widthSpec, int heightSpec, 1007 int[] measuredDimension) { 1008 View view = mRecycler.getViewForPosition(position); 1009 if (view != null) { 1010 LayoutParams p = (LayoutParams) view.getLayoutParams(); 1011 int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, 1012 getPaddingLeft() + getPaddingRight(), p.width); 1013 int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, 1014 getPaddingTop() + getPaddingBottom(), p.height); 1015 view.measure(childWidthSpec, childHeightSpec); 1016 measuredDimension[0] = view.getMeasuredWidth(); 1017 measuredDimension[1] = view.getMeasuredHeight(); 1018 mRecycler.recycleView(view); 1019 } 1020 } 1021 1022 private boolean processRowSizeSecondary(boolean measure) { 1023 if (mFixedRowSizeSecondary != 0) { 1024 return false; 1025 } 1026 1027 if (TRACE) TraceHelper.beginSection("processRowSizeSecondary"); 1028 CircularIntArray[] rows = mGrid == null ? null : mGrid.getItemPositionsInRows(); 1029 boolean changed = false; 1030 int scrapChildWidth = -1; 1031 int scrapChildHeight = -1; 1032 1033 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 1034 CircularIntArray row = rows == null ? null : rows[rowIndex]; 1035 final int rowItemsPairCount = row == null ? 0 : row.size(); 1036 int rowSize = -1; 1037 for (int rowItemPairIndex = 0; rowItemPairIndex < rowItemsPairCount; 1038 rowItemPairIndex += 2) { 1039 final int rowIndexStart = row.get(rowItemPairIndex); 1040 final int rowIndexEnd = row.get(rowItemPairIndex + 1); 1041 for (int i = rowIndexStart; i <= rowIndexEnd; i++) { 1042 final View view = findViewByPosition(i); 1043 if (view == null) { 1044 continue; 1045 } 1046 if (measure && view.isLayoutRequested()) { 1047 measureChild(view); 1048 } 1049 final int secondarySize = mOrientation == HORIZONTAL ? 1050 view.getMeasuredHeight() : view.getMeasuredWidth(); 1051 if (secondarySize > rowSize) { 1052 rowSize = secondarySize; 1053 } 1054 } 1055 } 1056 1057 final int itemCount = mState.getItemCount(); 1058 if (measure && rowSize < 0 && itemCount > 0) { 1059 if (scrapChildWidth < 0 && scrapChildHeight < 0) { 1060 int position; 1061 if (mFocusPosition == NO_POSITION) { 1062 position = 0; 1063 } else if (mFocusPosition >= itemCount) { 1064 position = itemCount - 1; 1065 } else { 1066 position = mFocusPosition; 1067 } 1068 measureScrapChild(position, 1069 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1070 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1071 mMeasuredDimension); 1072 scrapChildWidth = mMeasuredDimension[0]; 1073 scrapChildHeight = mMeasuredDimension[1]; 1074 if (DEBUG) Log.v(TAG, "measured scrap child: " + scrapChildWidth + 1075 " " + scrapChildHeight); 1076 } 1077 rowSize = mOrientation == HORIZONTAL ? scrapChildHeight : scrapChildWidth; 1078 } 1079 if (rowSize < 0) { 1080 rowSize = 0; 1081 } 1082 if (mRowSizeSecondary[rowIndex] != rowSize) { 1083 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 1084 ", " + rowSize); 1085 mRowSizeSecondary[rowIndex] = rowSize; 1086 changed = true; 1087 } 1088 } 1089 1090 if (TRACE) TraceHelper.endSection(); 1091 return changed; 1092 } 1093 1094 /** 1095 * Checks if we need to update row secondary sizes. 1096 */ 1097 private void updateRowSecondarySizeRefresh() { 1098 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 1099 if (mRowSecondarySizeRefresh) { 1100 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 1101 forceRequestLayout(); 1102 } 1103 } 1104 1105 private void forceRequestLayout() { 1106 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 1107 // RecyclerView prevents us from requesting layout in many cases 1108 // (during layout, during scroll, etc.) 1109 // For secondary row size wrap_content support we currently need a 1110 // second layout pass to update the measured size after having measured 1111 // and added child views in layoutChildren. 1112 // Force the second layout by posting a delayed runnable. 1113 // TODO: investigate allowing a second layout pass, 1114 // or move child add/measure logic to the measure phase. 1115 ViewCompat.postOnAnimation(mBaseGridView, mRequestLayoutRunnable); 1116 } 1117 1118 private final Runnable mRequestLayoutRunnable = new Runnable() { 1119 @Override 1120 public void run() { 1121 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 1122 requestLayout(); 1123 } 1124 }; 1125 1126 @Override 1127 public void onMeasure(Recycler recycler, State state, int widthSpec, int heightSpec) { 1128 saveContext(recycler, state); 1129 1130 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 1131 int measuredSizeSecondary; 1132 if (mOrientation == HORIZONTAL) { 1133 sizePrimary = MeasureSpec.getSize(widthSpec); 1134 sizeSecondary = MeasureSpec.getSize(heightSpec); 1135 modeSecondary = MeasureSpec.getMode(heightSpec); 1136 paddingSecondary = getPaddingTop() + getPaddingBottom(); 1137 } else { 1138 sizeSecondary = MeasureSpec.getSize(widthSpec); 1139 sizePrimary = MeasureSpec.getSize(heightSpec); 1140 modeSecondary = MeasureSpec.getMode(widthSpec); 1141 paddingSecondary = getPaddingLeft() + getPaddingRight(); 1142 } 1143 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 1144 " heightSpec " + Integer.toHexString(heightSpec) + 1145 " modeSecondary " + Integer.toHexString(modeSecondary) + 1146 " sizeSecondary " + sizeSecondary + " " + this); 1147 1148 mMaxSizeSecondary = sizeSecondary; 1149 1150 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 1151 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1152 mFixedRowSizeSecondary = 0; 1153 1154 if (mRowSizeSecondary == null || mRowSizeSecondary.length != mNumRows) { 1155 mRowSizeSecondary = new int[mNumRows]; 1156 } 1157 1158 // Measure all current children and update cached row heights 1159 processRowSizeSecondary(true); 1160 1161 switch (modeSecondary) { 1162 case MeasureSpec.UNSPECIFIED: 1163 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 1164 break; 1165 case MeasureSpec.AT_MOST: 1166 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 1167 mMaxSizeSecondary); 1168 break; 1169 case MeasureSpec.EXACTLY: 1170 measuredSizeSecondary = mMaxSizeSecondary; 1171 break; 1172 default: 1173 throw new IllegalStateException("wrong spec"); 1174 } 1175 1176 } else { 1177 switch (modeSecondary) { 1178 case MeasureSpec.UNSPECIFIED: 1179 if (mRowSizeSecondaryRequested == 0) { 1180 if (mOrientation == HORIZONTAL) { 1181 throw new IllegalStateException("Must specify rowHeight or view height"); 1182 } else { 1183 throw new IllegalStateException("Must specify columnWidth or view width"); 1184 } 1185 } 1186 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1187 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1188 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1189 * (mNumRows - 1) + paddingSecondary; 1190 break; 1191 case MeasureSpec.AT_MOST: 1192 case MeasureSpec.EXACTLY: 1193 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 1194 mNumRows = 1; 1195 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 1196 } else if (mNumRowsRequested == 0) { 1197 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1198 mNumRows = (sizeSecondary + mMarginSecondary) 1199 / (mRowSizeSecondaryRequested + mMarginSecondary); 1200 } else if (mRowSizeSecondaryRequested == 0) { 1201 mNumRows = mNumRowsRequested; 1202 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 1203 * (mNumRows - 1)) / mNumRows; 1204 } else { 1205 mNumRows = mNumRowsRequested; 1206 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1207 } 1208 measuredSizeSecondary = sizeSecondary; 1209 if (modeSecondary == MeasureSpec.AT_MOST) { 1210 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1211 * (mNumRows - 1) + paddingSecondary; 1212 if (childrenSize < measuredSizeSecondary) { 1213 measuredSizeSecondary = childrenSize; 1214 } 1215 } 1216 break; 1217 default: 1218 throw new IllegalStateException("wrong spec"); 1219 } 1220 } 1221 if (mOrientation == HORIZONTAL) { 1222 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1223 } else { 1224 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1225 } 1226 if (DEBUG) { 1227 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1228 " measuredSizeSecondary " + measuredSizeSecondary + 1229 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1230 " mNumRows " + mNumRows); 1231 } 1232 leaveContext(); 1233 } 1234 1235 private void measureChild(View child) { 1236 if (TRACE) TraceHelper.beginSection("measureChild"); 1237 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1238 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1239 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1240 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1241 int widthSpec, heightSpec; 1242 1243 if (mOrientation == HORIZONTAL) { 1244 widthSpec = ViewGroup.getChildMeasureSpec( 1245 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1246 0, lp.width); 1247 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1248 } else { 1249 heightSpec = ViewGroup.getChildMeasureSpec( 1250 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1251 0, lp.height); 1252 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1253 } 1254 child.measure(widthSpec, heightSpec); 1255 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1256 " widthSpec " + Integer.toHexString(widthSpec) + 1257 " heightSpec " + Integer.toHexString(heightSpec) + 1258 " measuredWidth " + child.getMeasuredWidth() + 1259 " measuredHeight " + child.getMeasuredHeight()); 1260 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1261 if (TRACE) TraceHelper.endSection(); 1262 } 1263 1264 private Grid.Provider mGridProvider = new Grid.Provider() { 1265 1266 @Override 1267 public int getCount() { 1268 return mState.getItemCount(); 1269 } 1270 1271 @Override 1272 public int createItem(int index, boolean append, Object[] item) { 1273 if (TRACE) TraceHelper.beginSection("createItem"); 1274 if (TRACE) TraceHelper.beginSection("getview"); 1275 View v = getViewForPosition(index); 1276 if (TRACE) TraceHelper.endSection(); 1277 // See recyclerView docs: we don't need re-add scraped view if it was removed. 1278 if (!((RecyclerView.LayoutParams) v.getLayoutParams()).isItemRemoved()) { 1279 if (TRACE) TraceHelper.beginSection("addView"); 1280 if (append) { 1281 addView(v); 1282 } else { 1283 addView(v, 0); 1284 } 1285 if (TRACE) TraceHelper.endSection(); 1286 if (mChildVisibility != -1) { 1287 v.setVisibility(mChildVisibility); 1288 } 1289 1290 if (mPendingMoveSmoothScroller != null) { 1291 mPendingMoveSmoothScroller.consumePendingMovesBeforeLayout(); 1292 } 1293 if (!mInLayout) { 1294 // when we are appending item during scroll pass and the item's position 1295 // matches the mFocusPosition, we should signal a childSelected event. 1296 // However if we are still running PendingMoveSmoothScroller, we defer and 1297 // signal the event in PendingMoveSmoothScroller.onStop(). This can 1298 // avoid lots of childSelected events during a long smooth scrolling and 1299 // increase performance. 1300 if (index == mFocusPosition && (mPendingMoveSmoothScroller == null 1301 || mPendingMoveSmoothScroller.mPendingMoves == 0)) { 1302 dispatchChildSelected(); 1303 } 1304 } else if (!mInFastRelayout) { 1305 // fastRelayout will dispatch event at end of onLayoutChildren(). 1306 // For full layout, two situations here: 1307 // 1. mInLayoutSearchFocus is false, dispatchChildSelected() at mFocusPosition. 1308 // 2. mInLayoutSearchFocus is true: dispatchChildSelected() on first child 1309 // equal to or after mFocusPosition that can take focus. 1310 if (!mInLayoutSearchFocus && index == mFocusPosition) { 1311 dispatchChildSelected(); 1312 } else if (mInLayoutSearchFocus && index >= mFocusPosition 1313 && v.hasFocusable()) { 1314 mFocusPosition = index; 1315 mInLayoutSearchFocus = false; 1316 dispatchChildSelected(); 1317 } 1318 } 1319 measureChild(v); 1320 } 1321 item[0] = v; 1322 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1323 } 1324 1325 @Override 1326 public void addItem(Object item, int index, int length, int rowIndex, int edge) { 1327 View v = (View) item; 1328 int start, end; 1329 if (edge == Integer.MIN_VALUE || edge == Integer.MAX_VALUE) { 1330 edge = !mGrid.isReversedFlow() ? mWindowAlignment.mainAxis().getPaddingLow() 1331 : mWindowAlignment.mainAxis().getSize() 1332 - mWindowAlignment.mainAxis().getPaddingHigh(); 1333 } 1334 boolean edgeIsMin = !mGrid.isReversedFlow(); 1335 if (edgeIsMin) { 1336 start = edge; 1337 end = edge + length; 1338 } else { 1339 start = edge - length; 1340 end = edge; 1341 } 1342 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1343 mChildrenStates.loadView(v, index); 1344 layoutChild(rowIndex, v, start, end, startSecondary); 1345 if (DEBUG) { 1346 Log.d(getTag(), "addView " + index + " " + v); 1347 } 1348 if (TRACE) TraceHelper.endSection(); 1349 1350 if (index == mGrid.getFirstVisibleIndex()) { 1351 if (!mGrid.isReversedFlow()) { 1352 updateScrollMin(); 1353 } else { 1354 updateScrollMax(); 1355 } 1356 } 1357 if (index == mGrid.getLastVisibleIndex()) { 1358 if (!mGrid.isReversedFlow()) { 1359 updateScrollMax(); 1360 } else { 1361 updateScrollMin(); 1362 } 1363 } 1364 if (!mInLayout && mPendingMoveSmoothScroller != null) { 1365 mPendingMoveSmoothScroller.consumePendingMovesAfterLayout(); 1366 } 1367 if (mChildLaidOutListener != null) { 1368 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(v); 1369 mChildLaidOutListener.onChildLaidOut(mBaseGridView, v, index, 1370 vh == null ? NO_ID : vh.getItemId()); 1371 } 1372 } 1373 1374 @Override 1375 public void removeItem(int index) { 1376 if (TRACE) TraceHelper.beginSection("removeItem"); 1377 View v = findViewByPosition(index); 1378 if (mInLayout) { 1379 detachAndScrapView(v, mRecycler); 1380 } else { 1381 removeAndRecycleView(v, mRecycler); 1382 } 1383 if (TRACE) TraceHelper.endSection(); 1384 } 1385 1386 @Override 1387 public int getEdge(int index) { 1388 if (mReverseFlowPrimary) { 1389 return getViewMax(findViewByPosition(index)); 1390 } else { 1391 return getViewMin(findViewByPosition(index)); 1392 } 1393 } 1394 1395 @Override 1396 public int getSize(int index) { 1397 final View v = findViewByPosition(index); 1398 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1399 } 1400 }; 1401 1402 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1403 if (TRACE) TraceHelper.beginSection("layoutChild"); 1404 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1405 : v.getMeasuredWidth(); 1406 if (mFixedRowSizeSecondary > 0) { 1407 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1408 } 1409 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1410 final int horizontalGravity = (mReverseFlowPrimary || mReverseFlowSecondary) ? 1411 Gravity.getAbsoluteGravity(mGravity & Gravity.RELATIVE_HORIZONTAL_GRAVITY_MASK, View.LAYOUT_DIRECTION_RTL) : 1412 mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1413 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1414 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1415 // do nothing 1416 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1417 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1418 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1419 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1420 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1421 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1422 } 1423 int left, top, right, bottom; 1424 if (mOrientation == HORIZONTAL) { 1425 left = start; 1426 top = startSecondary; 1427 right = end; 1428 bottom = startSecondary + sizeSecondary; 1429 } else { 1430 top = start; 1431 left = startSecondary; 1432 bottom = end; 1433 right = startSecondary + sizeSecondary; 1434 } 1435 v.layout(left, top, right, bottom); 1436 updateChildOpticalInsets(v, left, top, right, bottom); 1437 updateChildAlignments(v); 1438 if (TRACE) TraceHelper.endSection(); 1439 } 1440 1441 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1442 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1443 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1444 v.getRight() - right, v.getBottom() - bottom); 1445 } 1446 1447 private void updateChildAlignments(View v) { 1448 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1449 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1450 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1451 } 1452 1453 private void updateChildAlignments() { 1454 for (int i = 0, c = getChildCount(); i < c; i++) { 1455 updateChildAlignments(getChildAt(i)); 1456 } 1457 } 1458 1459 private void removeInvisibleViewsAtEnd() { 1460 if (mPruneChild) { 1461 mGrid.removeInvisibleItemsAtEnd(mFocusPosition, 1462 mReverseFlowPrimary ? 0 : mSizePrimary); 1463 } 1464 } 1465 1466 private void removeInvisibleViewsAtFront() { 1467 if (mPruneChild) { 1468 mGrid.removeInvisibleItemsAtFront(mFocusPosition, 1469 mReverseFlowPrimary ? mSizePrimary : 0); 1470 } 1471 } 1472 1473 private boolean appendOneColumnVisibleItems() { 1474 return mGrid.appendOneColumnVisibleItems(); 1475 } 1476 1477 private boolean prependOneColumnVisibleItems() { 1478 return mGrid.prependOneColumnVisibleItems(); 1479 } 1480 1481 private void appendVisibleItems() { 1482 mGrid.appendVisibleItems(mReverseFlowPrimary ? 0 : mSizePrimary); 1483 } 1484 1485 private void prependVisibleItems() { 1486 mGrid.prependVisibleItems(mReverseFlowPrimary ? mSizePrimary : 0); 1487 } 1488 1489 /** 1490 * Fast layout when there is no structure change, adapter change, etc. 1491 * It will layout all views was layout requested or updated, until hit a view 1492 * with different size, then it break and detachAndScrap all views after that. 1493 */ 1494 private void fastRelayout() { 1495 boolean invalidateAfter = false; 1496 final int childCount = getChildCount(); 1497 int position = -1; 1498 for (int index = 0; index < childCount; index++) { 1499 View view = getChildAt(index); 1500 position = getPositionByIndex(index); 1501 Grid.Location location = mGrid.getLocation(position); 1502 if (location == null) { 1503 if (DEBUG) Log.w(getTag(), "fastRelayout(): no Location at " + position); 1504 invalidateAfter = true; 1505 break; 1506 } 1507 1508 int startSecondary = getRowStartSecondary(location.row) - mScrollOffsetSecondary; 1509 int primarySize, end; 1510 int start = getViewMin(view); 1511 int oldPrimarySize = (mOrientation == HORIZONTAL) ? 1512 view.getMeasuredWidth() : 1513 view.getMeasuredHeight(); 1514 1515 LayoutParams lp = (LayoutParams) view.getLayoutParams(); 1516 if (lp.viewNeedsUpdate()) { 1517 int viewIndex = mBaseGridView.indexOfChild(view); 1518 detachAndScrapView(view, mRecycler); 1519 view = getViewForPosition(position); 1520 addView(view, viewIndex); 1521 } 1522 1523 if (view.isLayoutRequested()) { 1524 measureChild(view); 1525 } 1526 if (mOrientation == HORIZONTAL) { 1527 primarySize = view.getMeasuredWidth(); 1528 end = start + primarySize; 1529 } else { 1530 primarySize = view.getMeasuredHeight(); 1531 end = start + primarySize; 1532 } 1533 layoutChild(location.row, view, start, end, startSecondary); 1534 if (oldPrimarySize != primarySize) { 1535 // size changed invalidate remaining Locations 1536 if (DEBUG) Log.d(getTag(), "fastRelayout: view size changed at " + position); 1537 invalidateAfter = true; 1538 break; 1539 } 1540 } 1541 if (invalidateAfter) { 1542 final int savedLastPos = mGrid.getLastVisibleIndex(); 1543 mGrid.invalidateItemsAfter(position); 1544 if (mPruneChild) { 1545 // in regular prune child mode, we just append items up to edge limit 1546 appendVisibleItems(); 1547 } else { 1548 // prune disabled(e.g. in RowsFragment transition): append all removed items 1549 while (mGrid.appendOneColumnVisibleItems() 1550 && mGrid.getLastVisibleIndex() < savedLastPos); 1551 } 1552 } 1553 updateScrollMin(); 1554 updateScrollMax(); 1555 updateScrollSecondAxis(); 1556 } 1557 1558 public void removeAndRecycleAllViews(RecyclerView.Recycler recycler) { 1559 if (TRACE) TraceHelper.beginSection("removeAndRecycleAllViews"); 1560 if (DEBUG) Log.v(TAG, "removeAndRecycleAllViews " + getChildCount()); 1561 for (int i = getChildCount() - 1; i >= 0; i--) { 1562 removeAndRecycleViewAt(i, recycler); 1563 } 1564 if (TRACE) TraceHelper.endSection(); 1565 } 1566 1567 // Lays out items based on the current scroll position 1568 @Override 1569 public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) { 1570 if (DEBUG) { 1571 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1572 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1573 + " inPreLayout " + state.isPreLayout() 1574 + " didStructureChange " + state.didStructureChange() 1575 + " mForceFullLayout " + mForceFullLayout); 1576 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1577 } 1578 1579 if (mNumRows == 0) { 1580 // haven't done measure yet 1581 return; 1582 } 1583 final int itemCount = state.getItemCount(); 1584 if (itemCount < 0) { 1585 return; 1586 } 1587 1588 if (!mLayoutEnabled) { 1589 discardLayoutInfo(); 1590 removeAndRecycleAllViews(recycler); 1591 return; 1592 } 1593 mInLayout = true; 1594 1595 final boolean scrollToFocus = !isSmoothScrolling() 1596 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED; 1597 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1598 mFocusPosition = mFocusPosition + mFocusPositionOffset; 1599 mFocusPositionOffset = 0; 1600 } 1601 saveContext(recycler, state); 1602 1603 // Track the old focus view so we can adjust our system scroll position 1604 // so that any scroll animations happening now will remain valid. 1605 // We must use same delta in Pre Layout (if prelayout exists) and second layout. 1606 // So we cache the deltas in PreLayout and use it in second layout. 1607 int delta = 0, deltaSecondary = 0; 1608 if (mFocusPosition != NO_POSITION && scrollToFocus 1609 && mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE) { 1610 // FIXME: we should get the remaining scroll animation offset from RecyclerView 1611 View focusView = findViewByPosition(mFocusPosition); 1612 if (focusView != null) { 1613 delta = mWindowAlignment.mainAxis().getSystemScrollPos(mScrollOffsetPrimary 1614 + getViewCenter(focusView), false, false) - mScrollOffsetPrimary; 1615 deltaSecondary = mWindowAlignment.secondAxis().getSystemScrollPos( 1616 mScrollOffsetSecondary + getViewCenterSecondary(focusView), 1617 false, false) - mScrollOffsetSecondary; 1618 } 1619 } 1620 1621 boolean hadFocus = mBaseGridView.hasFocus(); 1622 int savedFocusPos = mFocusPosition; 1623 if (mInFastRelayout = layoutInit()) { 1624 fastRelayout(); 1625 View focusView = findViewByPosition(mFocusPosition); 1626 if (scrollToFocus) { 1627 scrollToView(focusView, false); 1628 } 1629 if (focusView != null && hadFocus) { 1630 focusView.requestFocus(); 1631 } 1632 } else { 1633 mInLayoutSearchFocus = hadFocus; 1634 if (mFocusPosition != NO_POSITION) { 1635 // appends items till focus position. 1636 while (appendOneColumnVisibleItems() 1637 && findViewByPosition(mFocusPosition) == null) ; 1638 } 1639 // multiple rounds: scrollToView of first round may drag first/last child into 1640 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1641 int oldFirstVisible; 1642 int oldLastVisible; 1643 do { 1644 updateScrollMin(); 1645 updateScrollMax(); 1646 oldFirstVisible = mGrid.getFirstVisibleIndex(); 1647 oldLastVisible = mGrid.getLastVisibleIndex(); 1648 View focusView = findViewByPosition(mFocusPosition); 1649 // we need force to initialize the child view's position 1650 scrollToView(focusView, false); 1651 if (focusView != null && hadFocus) { 1652 focusView.requestFocus(); 1653 } 1654 appendVisibleItems(); 1655 prependVisibleItems(); 1656 removeInvisibleViewsAtFront(); 1657 removeInvisibleViewsAtEnd(); 1658 } while (mGrid.getFirstVisibleIndex() != oldFirstVisible || 1659 mGrid.getLastVisibleIndex() != oldLastVisible); 1660 } 1661 1662 if (scrollToFocus) { 1663 scrollDirectionPrimary(-delta); 1664 scrollDirectionSecondary(-deltaSecondary); 1665 } 1666 appendVisibleItems(); 1667 prependVisibleItems(); 1668 removeInvisibleViewsAtFront(); 1669 removeInvisibleViewsAtEnd(); 1670 1671 if (DEBUG) { 1672 StringWriter sw = new StringWriter(); 1673 PrintWriter pw = new PrintWriter(sw); 1674 mGrid.debugPrint(pw); 1675 Log.d(getTag(), sw.toString()); 1676 } 1677 1678 if (mRowSecondarySizeRefresh) { 1679 mRowSecondarySizeRefresh = false; 1680 } else { 1681 updateRowSecondarySizeRefresh(); 1682 } 1683 1684 // For fastRelayout, only dispatch event when focus position changes. 1685 if (mInFastRelayout && mFocusPosition != savedFocusPos) { 1686 dispatchChildSelected(); 1687 } else if (!mInFastRelayout && mInLayoutSearchFocus) { 1688 // For full layout we dispatchChildSelected() in createItem() unless searched all 1689 // children and found none is focusable then dispatchChildSelected() here. 1690 dispatchChildSelected(); 1691 } 1692 1693 mInLayout = false; 1694 leaveContext(); 1695 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1696 } 1697 1698 private void offsetChildrenSecondary(int increment) { 1699 final int childCount = getChildCount(); 1700 if (mOrientation == HORIZONTAL) { 1701 for (int i = 0; i < childCount; i++) { 1702 getChildAt(i).offsetTopAndBottom(increment); 1703 } 1704 } else { 1705 for (int i = 0; i < childCount; i++) { 1706 getChildAt(i).offsetLeftAndRight(increment); 1707 } 1708 } 1709 } 1710 1711 private void offsetChildrenPrimary(int increment) { 1712 final int childCount = getChildCount(); 1713 if (mOrientation == VERTICAL) { 1714 for (int i = 0; i < childCount; i++) { 1715 getChildAt(i).offsetTopAndBottom(increment); 1716 } 1717 } else { 1718 for (int i = 0; i < childCount; i++) { 1719 getChildAt(i).offsetLeftAndRight(increment); 1720 } 1721 } 1722 } 1723 1724 @Override 1725 public int scrollHorizontallyBy(int dx, Recycler recycler, RecyclerView.State state) { 1726 if (DEBUG) Log.v(getTag(), "scrollHorizontallyBy " + dx); 1727 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1728 return 0; 1729 } 1730 saveContext(recycler, state); 1731 int result; 1732 if (mOrientation == HORIZONTAL) { 1733 result = scrollDirectionPrimary(dx); 1734 } else { 1735 result = scrollDirectionSecondary(dx); 1736 } 1737 leaveContext(); 1738 return result; 1739 } 1740 1741 @Override 1742 public int scrollVerticallyBy(int dy, Recycler recycler, RecyclerView.State state) { 1743 if (DEBUG) Log.v(getTag(), "scrollVerticallyBy " + dy); 1744 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1745 return 0; 1746 } 1747 saveContext(recycler, state); 1748 int result; 1749 if (mOrientation == VERTICAL) { 1750 result = scrollDirectionPrimary(dy); 1751 } else { 1752 result = scrollDirectionSecondary(dy); 1753 } 1754 leaveContext(); 1755 return result; 1756 } 1757 1758 // scroll in main direction may add/prune views 1759 private int scrollDirectionPrimary(int da) { 1760 if (TRACE) TraceHelper.beginSection("scrollPrimary"); 1761 boolean isMaxUnknown = false, isMinUnknown = false; 1762 int minScroll = 0, maxScroll = 0; 1763 if (da > 0) { 1764 isMaxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1765 if (!isMaxUnknown) { 1766 maxScroll = mWindowAlignment.mainAxis().getMaxScroll(); 1767 if (mScrollOffsetPrimary + da > maxScroll) { 1768 da = maxScroll - mScrollOffsetPrimary; 1769 } 1770 } 1771 } else if (da < 0) { 1772 isMinUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1773 if (!isMinUnknown) { 1774 minScroll = mWindowAlignment.mainAxis().getMinScroll(); 1775 if (mScrollOffsetPrimary + da < minScroll) { 1776 da = minScroll - mScrollOffsetPrimary; 1777 } 1778 } 1779 } 1780 if (da == 0) { 1781 if (TRACE) TraceHelper.endSection(); 1782 return 0; 1783 } 1784 offsetChildrenPrimary(-da); 1785 mScrollOffsetPrimary += da; 1786 if (mInLayout) { 1787 if (TRACE) TraceHelper.endSection(); 1788 return da; 1789 } 1790 1791 int childCount = getChildCount(); 1792 boolean updated; 1793 1794 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1795 prependVisibleItems(); 1796 } else { 1797 appendVisibleItems(); 1798 } 1799 updated = getChildCount() > childCount; 1800 childCount = getChildCount(); 1801 1802 if (TRACE) TraceHelper.beginSection("remove"); 1803 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1804 removeInvisibleViewsAtEnd(); 1805 } else { 1806 removeInvisibleViewsAtFront(); 1807 } 1808 if (TRACE) TraceHelper.endSection(); 1809 updated |= getChildCount() < childCount; 1810 if (updated) { 1811 updateRowSecondarySizeRefresh(); 1812 } 1813 1814 mBaseGridView.invalidate(); 1815 if (TRACE) TraceHelper.endSection(); 1816 return da; 1817 } 1818 1819 // scroll in second direction will not add/prune views 1820 private int scrollDirectionSecondary(int dy) { 1821 if (dy == 0) { 1822 return 0; 1823 } 1824 offsetChildrenSecondary(-dy); 1825 mScrollOffsetSecondary += dy; 1826 mBaseGridView.invalidate(); 1827 return dy; 1828 } 1829 1830 private void updateScrollMax() { 1831 int highVisiblePos = (!mReverseFlowPrimary) ? mGrid.getLastVisibleIndex() 1832 : mGrid.getFirstVisibleIndex(); 1833 int highMaxPos = (!mReverseFlowPrimary) ? mState.getItemCount() - 1 : 0; 1834 if (highVisiblePos < 0) { 1835 return; 1836 } 1837 final boolean highAvailable = highVisiblePos == highMaxPos; 1838 final boolean maxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1839 if (!highAvailable && maxUnknown) { 1840 return; 1841 } 1842 int maxEdge = mGrid.findRowMax(true, sTwoInts) + mScrollOffsetPrimary; 1843 int rowIndex = sTwoInts[0]; 1844 int pos = sTwoInts[1]; 1845 int savedMaxEdge = mWindowAlignment.mainAxis().getMaxEdge(); 1846 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1847 int maxScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1848 mWindowAlignment.mainAxis().setMaxEdge(savedMaxEdge); 1849 1850 if (highAvailable) { 1851 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1852 mWindowAlignment.mainAxis().setMaxScroll(maxScroll); 1853 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge + 1854 " scrollMax to " + maxScroll); 1855 } else { 1856 mWindowAlignment.mainAxis().invalidateScrollMax(); 1857 if (DEBUG) Log.v(getTag(), "Invalidate scrollMax since it should be " 1858 + "greater than " + maxScroll); 1859 } 1860 } 1861 1862 private void updateScrollMin() { 1863 int lowVisiblePos = (!mReverseFlowPrimary) ? mGrid.getFirstVisibleIndex() 1864 : mGrid.getLastVisibleIndex(); 1865 int lowMinPos = (!mReverseFlowPrimary) ? 0 : mState.getItemCount() - 1; 1866 if (lowVisiblePos < 0) { 1867 return; 1868 } 1869 final boolean lowAvailable = lowVisiblePos == lowMinPos; 1870 final boolean minUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1871 if (!lowAvailable && minUnknown) { 1872 return; 1873 } 1874 int minEdge = mGrid.findRowMin(false, sTwoInts) + mScrollOffsetPrimary; 1875 int rowIndex = sTwoInts[0]; 1876 int pos = sTwoInts[1]; 1877 int savedMinEdge = mWindowAlignment.mainAxis().getMinEdge(); 1878 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1879 int minScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1880 mWindowAlignment.mainAxis().setMinEdge(savedMinEdge); 1881 1882 if (lowAvailable) { 1883 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1884 mWindowAlignment.mainAxis().setMinScroll(minScroll); 1885 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge + 1886 " scrollMin to " + minScroll); 1887 } else { 1888 mWindowAlignment.mainAxis().invalidateScrollMin(); 1889 if (DEBUG) Log.v(getTag(), "Invalidate scrollMin, since it should be " 1890 + "less than " + minScroll); 1891 } 1892 } 1893 1894 private void updateScrollSecondAxis() { 1895 mWindowAlignment.secondAxis().setMinEdge(0); 1896 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1897 } 1898 1899 private void initScrollController() { 1900 mWindowAlignment.reset(); 1901 mWindowAlignment.horizontal.setSize(getWidth()); 1902 mWindowAlignment.vertical.setSize(getHeight()); 1903 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1904 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1905 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1906 mScrollOffsetPrimary = -mWindowAlignment.mainAxis().getPaddingLow(); 1907 mScrollOffsetSecondary = -mWindowAlignment.secondAxis().getPaddingLow(); 1908 1909 if (DEBUG) { 1910 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1911 + " mWindowAlignment " + mWindowAlignment 1912 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1913 } 1914 } 1915 1916 private void updateScrollController() { 1917 // mScrollOffsetPrimary and mScrollOffsetSecondary includes the padding. 1918 // e.g. when topPadding is 16 for horizontal grid view, the initial 1919 // mScrollOffsetSecondary is -16. fastRelayout() put views based on offsets(not padding), 1920 // when padding changes to 20, we also need update mScrollOffsetSecondary to -20 before 1921 // fastRelayout() is performed 1922 int paddingPrimaryDiff, paddingSecondaryDiff; 1923 if (mOrientation == HORIZONTAL) { 1924 paddingPrimaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1925 paddingSecondaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1926 } else { 1927 paddingPrimaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1928 paddingSecondaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1929 } 1930 mScrollOffsetPrimary -= paddingPrimaryDiff; 1931 mScrollOffsetSecondary -= paddingSecondaryDiff; 1932 1933 mWindowAlignment.horizontal.setSize(getWidth()); 1934 mWindowAlignment.vertical.setSize(getHeight()); 1935 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1936 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1937 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1938 1939 if (DEBUG) { 1940 Log.v(getTag(), "updateScrollController mSizePrimary " + mSizePrimary 1941 + " mWindowAlignment " + mWindowAlignment 1942 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1943 } 1944 } 1945 1946 public void setSelection(RecyclerView parent, int position) { 1947 setSelection(parent, position, false); 1948 } 1949 1950 public void setSelectionSmooth(RecyclerView parent, int position) { 1951 setSelection(parent, position, true); 1952 } 1953 1954 public int getSelection() { 1955 return mFocusPosition; 1956 } 1957 1958 public void setSelection(RecyclerView parent, int position, boolean smooth) { 1959 if (mFocusPosition != position && position != NO_POSITION) { 1960 scrollToSelection(parent, position, smooth); 1961 } 1962 } 1963 1964 private void scrollToSelection(RecyclerView parent, int position, boolean smooth) { 1965 if (TRACE) TraceHelper.beginSection("scrollToSelection"); 1966 View view = findViewByPosition(position); 1967 if (view != null) { 1968 mInSelection = true; 1969 scrollToView(view, smooth); 1970 mInSelection = false; 1971 } else { 1972 mFocusPosition = position; 1973 mFocusPositionOffset = 0; 1974 if (!mLayoutEnabled) { 1975 return; 1976 } 1977 if (smooth) { 1978 if (!hasDoneFirstLayout()) { 1979 Log.w(getTag(), "setSelectionSmooth should " + 1980 "not be called before first layout pass"); 1981 return; 1982 } 1983 startPositionSmoothScroller(position); 1984 } else { 1985 mForceFullLayout = true; 1986 parent.requestLayout(); 1987 } 1988 } 1989 if (TRACE) TraceHelper.endSection(); 1990 } 1991 1992 void startPositionSmoothScroller(int position) { 1993 LinearSmoothScroller linearSmoothScroller = new GridLinearSmoothScroller() { 1994 @Override 1995 public PointF computeScrollVectorForPosition(int targetPosition) { 1996 if (getChildCount() == 0) { 1997 return null; 1998 } 1999 final int firstChildPos = getPosition(getChildAt(0)); 2000 // TODO We should be able to deduce direction from bounds of current and target 2001 // focus, rather than making assumptions about positions and directionality 2002 final boolean isStart = mReverseFlowPrimary ? targetPosition > firstChildPos 2003 : targetPosition < firstChildPos; 2004 final int direction = isStart ? -1 : 1; 2005 if (mOrientation == HORIZONTAL) { 2006 return new PointF(direction, 0); 2007 } else { 2008 return new PointF(0, direction); 2009 } 2010 } 2011 2012 }; 2013 linearSmoothScroller.setTargetPosition(position); 2014 startSmoothScroll(linearSmoothScroller); 2015 } 2016 2017 private void processPendingMovement(boolean forward) { 2018 if (forward ? hasCreatedLastItem() : hasCreatedFirstItem()) { 2019 return; 2020 } 2021 if (mPendingMoveSmoothScroller == null) { 2022 // Stop existing scroller and create a new PendingMoveSmoothScroller. 2023 mBaseGridView.stopScroll(); 2024 PendingMoveSmoothScroller linearSmoothScroller = new PendingMoveSmoothScroller( 2025 forward ? 1 : -1, mNumRows > 1); 2026 mFocusPositionOffset = 0; 2027 startSmoothScroll(linearSmoothScroller); 2028 if (linearSmoothScroller.isRunning()) { 2029 mPendingMoveSmoothScroller = linearSmoothScroller; 2030 } 2031 } else { 2032 if (forward) { 2033 mPendingMoveSmoothScroller.increasePendingMoves(); 2034 } else { 2035 mPendingMoveSmoothScroller.decreasePendingMoves(); 2036 } 2037 } 2038 } 2039 2040 @Override 2041 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 2042 if (DEBUG) Log.v(getTag(), "onItemsAdded positionStart " 2043 + positionStart + " itemCount " + itemCount); 2044 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2045 int pos = mFocusPosition + mFocusPositionOffset; 2046 if (positionStart <= pos) { 2047 mFocusPositionOffset += itemCount; 2048 } 2049 } 2050 mChildrenStates.clear(); 2051 } 2052 2053 @Override 2054 public void onItemsChanged(RecyclerView recyclerView) { 2055 if (DEBUG) Log.v(getTag(), "onItemsChanged"); 2056 mFocusPositionOffset = 0; 2057 mChildrenStates.clear(); 2058 } 2059 2060 @Override 2061 public void onItemsRemoved(RecyclerView recyclerView, int positionStart, int itemCount) { 2062 if (DEBUG) Log.v(getTag(), "onItemsRemoved positionStart " 2063 + positionStart + " itemCount " + itemCount); 2064 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2065 int pos = mFocusPosition + mFocusPositionOffset; 2066 if (positionStart <= pos) { 2067 if (positionStart + itemCount > pos) { 2068 // stop updating offset after the focus item was removed 2069 mFocusPositionOffset = Integer.MIN_VALUE; 2070 } else { 2071 mFocusPositionOffset -= itemCount; 2072 } 2073 } 2074 } 2075 mChildrenStates.clear(); 2076 } 2077 2078 @Override 2079 public void onItemsMoved(RecyclerView recyclerView, int fromPosition, int toPosition, 2080 int itemCount) { 2081 if (DEBUG) Log.v(getTag(), "onItemsMoved fromPosition " 2082 + fromPosition + " toPosition " + toPosition); 2083 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2084 int pos = mFocusPosition + mFocusPositionOffset; 2085 if (fromPosition <= pos && pos < fromPosition + itemCount) { 2086 // moved items include focused position 2087 mFocusPositionOffset += toPosition - fromPosition; 2088 } else if (fromPosition < pos && toPosition > pos - itemCount) { 2089 // move items before focus position to after focused position 2090 mFocusPositionOffset -= itemCount; 2091 } else if (fromPosition > pos && toPosition < pos) { 2092 // move items after focus position to before focused position 2093 mFocusPositionOffset += itemCount; 2094 } 2095 } 2096 mChildrenStates.clear(); 2097 } 2098 2099 @Override 2100 public void onItemsUpdated(RecyclerView recyclerView, int positionStart, int itemCount) { 2101 if (DEBUG) Log.v(getTag(), "onItemsUpdated positionStart " 2102 + positionStart + " itemCount " + itemCount); 2103 for (int i = positionStart, end = positionStart + itemCount; i < end; i++) { 2104 mChildrenStates.remove(i); 2105 } 2106 } 2107 2108 @Override 2109 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 2110 if (mFocusSearchDisabled) { 2111 return true; 2112 } 2113 if (getPositionByView(child) == NO_POSITION) { 2114 // This shouldn't happen, but in case it does be sure not to attempt a 2115 // scroll to a view whose item has been removed. 2116 return true; 2117 } 2118 if (!mInLayout && !mInSelection) { 2119 scrollToView(child, true); 2120 } 2121 return true; 2122 } 2123 2124 @Override 2125 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 2126 boolean immediate) { 2127 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 2128 return false; 2129 } 2130 2131 int getScrollOffsetX() { 2132 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 2133 } 2134 2135 int getScrollOffsetY() { 2136 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 2137 } 2138 2139 public void getViewSelectedOffsets(View view, int[] offsets) { 2140 if (mOrientation == HORIZONTAL) { 2141 offsets[0] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2142 offsets[1] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2143 } else { 2144 offsets[1] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2145 offsets[0] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2146 } 2147 } 2148 2149 private int getPrimarySystemScrollPosition(View view) { 2150 final int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 2151 final int viewMin = getViewMin(view); 2152 final int viewMax = getViewMax(view); 2153 // TODO: change to use State object in onRequestChildFocus() 2154 boolean isMin, isMax; 2155 if (!mReverseFlowPrimary) { 2156 isMin = mGrid.getFirstVisibleIndex() == 0; 2157 isMax = mGrid.getLastVisibleIndex() == (mState == null ? 2158 getItemCount() : mState.getItemCount()) - 1; 2159 } else { 2160 isMax = mGrid.getFirstVisibleIndex() == 0; 2161 isMin = mGrid.getLastVisibleIndex() == (mState == null ? 2162 getItemCount() : mState.getItemCount()) - 1; 2163 } 2164 for (int i = getChildCount() - 1; (isMin || isMax) && i >= 0; i--) { 2165 View v = getChildAt(i); 2166 if (v == view || v == null) { 2167 continue; 2168 } 2169 if (isMin && getViewMin(v) < viewMin) { 2170 isMin = false; 2171 } 2172 if (isMax && getViewMax(v) > viewMax) { 2173 isMax = false; 2174 } 2175 } 2176 return mWindowAlignment.mainAxis().getSystemScrollPos(viewCenterPrimary, isMin, isMax); 2177 } 2178 2179 private int getSecondarySystemScrollPosition(View view) { 2180 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 2181 int pos = getPositionByView(view); 2182 Grid.Location location = mGrid.getLocation(pos); 2183 final int row = location.row; 2184 final boolean isMin, isMax; 2185 if (!mReverseFlowSecondary) { 2186 isMin = row == 0; 2187 isMax = row == mGrid.getNumRows() - 1; 2188 } else { 2189 isMax = row == 0; 2190 isMin = row == mGrid.getNumRows() - 1; 2191 } 2192 return mWindowAlignment.secondAxis().getSystemScrollPos(viewCenterSecondary, isMin, isMax); 2193 } 2194 2195 /** 2196 * Scroll to a given child view and change mFocusPosition. 2197 */ 2198 private void scrollToView(View view, boolean smooth) { 2199 int newFocusPosition = getPositionByView(view); 2200 if (newFocusPosition != mFocusPosition) { 2201 mFocusPosition = newFocusPosition; 2202 mFocusPositionOffset = 0; 2203 if (!mInLayout) { 2204 dispatchChildSelected(); 2205 } 2206 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 2207 mBaseGridView.invalidate(); 2208 } 2209 } 2210 if (view == null) { 2211 return; 2212 } 2213 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 2214 // transfer focus to the child if it does not have focus yet (e.g. triggered 2215 // by setSelection()) 2216 view.requestFocus(); 2217 } 2218 if (!mScrollEnabled && smooth) { 2219 return; 2220 } 2221 if (getScrollPosition(view, sTwoInts)) { 2222 scrollGrid(sTwoInts[0], sTwoInts[1], smooth); 2223 } 2224 } 2225 2226 private boolean getScrollPosition(View view, int[] deltas) { 2227 switch (mFocusScrollStrategy) { 2228 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2229 default: 2230 return getAlignedPosition(view, deltas); 2231 case BaseGridView.FOCUS_SCROLL_ITEM: 2232 case BaseGridView.FOCUS_SCROLL_PAGE: 2233 return getNoneAlignedPosition(view, deltas); 2234 } 2235 } 2236 2237 private boolean getNoneAlignedPosition(View view, int[] deltas) { 2238 int pos = getPositionByView(view); 2239 int viewMin = getViewMin(view); 2240 int viewMax = getViewMax(view); 2241 // we either align "firstView" to left/top padding edge 2242 // or align "lastView" to right/bottom padding edge 2243 View firstView = null; 2244 View lastView = null; 2245 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 2246 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 2247 final int row = mGrid.getRowIndex(pos); 2248 if (viewMin < paddingLow) { 2249 // view enters low padding area: 2250 firstView = view; 2251 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2252 // scroll one "page" left/top, 2253 // align first visible item of the "page" at the low padding edge. 2254 while (prependOneColumnVisibleItems()) { 2255 CircularIntArray positions = 2256 mGrid.getItemPositionsInRows(mGrid.getFirstVisibleIndex(), pos)[row]; 2257 firstView = findViewByPosition(positions.get(0)); 2258 if (viewMax - getViewMin(firstView) > clientSize) { 2259 if (positions.size() > 2) { 2260 firstView = findViewByPosition(positions.get(2)); 2261 } 2262 break; 2263 } 2264 } 2265 } 2266 } else if (viewMax > clientSize + paddingLow) { 2267 // view enters high padding area: 2268 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2269 // scroll whole one page right/bottom, align view at the low padding edge. 2270 firstView = view; 2271 do { 2272 CircularIntArray positions = 2273 mGrid.getItemPositionsInRows(pos, mGrid.getLastVisibleIndex())[row]; 2274 lastView = findViewByPosition(positions.get(positions.size() - 1)); 2275 if (getViewMax(lastView) - viewMin > clientSize) { 2276 lastView = null; 2277 break; 2278 } 2279 } while (appendOneColumnVisibleItems()); 2280 if (lastView != null) { 2281 // however if we reached end, we should align last view. 2282 firstView = null; 2283 } 2284 } else { 2285 lastView = view; 2286 } 2287 } 2288 int scrollPrimary = 0; 2289 int scrollSecondary = 0; 2290 if (firstView != null) { 2291 scrollPrimary = getViewMin(firstView) - paddingLow; 2292 } else if (lastView != null) { 2293 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 2294 } 2295 View secondaryAlignedView; 2296 if (firstView != null) { 2297 secondaryAlignedView = firstView; 2298 } else if (lastView != null) { 2299 secondaryAlignedView = lastView; 2300 } else { 2301 secondaryAlignedView = view; 2302 } 2303 scrollSecondary = getSecondarySystemScrollPosition(secondaryAlignedView); 2304 scrollSecondary -= mScrollOffsetSecondary; 2305 if (scrollPrimary != 0 || scrollSecondary != 0) { 2306 deltas[0] = scrollPrimary; 2307 deltas[1] = scrollSecondary; 2308 return true; 2309 } 2310 return false; 2311 } 2312 2313 private boolean getAlignedPosition(View view, int[] deltas) { 2314 int scrollPrimary = getPrimarySystemScrollPosition(view); 2315 int scrollSecondary = getSecondarySystemScrollPosition(view); 2316 if (DEBUG) { 2317 Log.v(getTag(), "getAlignedPosition " + scrollPrimary + " " + scrollSecondary 2318 + " " + mWindowAlignment); 2319 Log.v(getTag(), "getAlignedPosition " + mScrollOffsetPrimary + " " + mScrollOffsetSecondary); 2320 } 2321 scrollPrimary -= mScrollOffsetPrimary; 2322 scrollSecondary -= mScrollOffsetSecondary; 2323 if (scrollPrimary != 0 || scrollSecondary != 0) { 2324 deltas[0] = scrollPrimary; 2325 deltas[1] = scrollSecondary; 2326 return true; 2327 } 2328 return false; 2329 } 2330 2331 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 2332 if (mInLayout) { 2333 scrollDirectionPrimary(scrollPrimary); 2334 scrollDirectionSecondary(scrollSecondary); 2335 } else { 2336 int scrollX; 2337 int scrollY; 2338 if (mOrientation == HORIZONTAL) { 2339 scrollX = scrollPrimary; 2340 scrollY = scrollSecondary; 2341 } else { 2342 scrollX = scrollSecondary; 2343 scrollY = scrollPrimary; 2344 } 2345 if (smooth) { 2346 mBaseGridView.smoothScrollBy(scrollX, scrollY); 2347 } else { 2348 mBaseGridView.scrollBy(scrollX, scrollY); 2349 } 2350 } 2351 } 2352 2353 public void setPruneChild(boolean pruneChild) { 2354 if (mPruneChild != pruneChild) { 2355 mPruneChild = pruneChild; 2356 if (mPruneChild) { 2357 requestLayout(); 2358 } 2359 } 2360 } 2361 2362 public boolean getPruneChild() { 2363 return mPruneChild; 2364 } 2365 2366 public void setScrollEnabled(boolean scrollEnabled) { 2367 if (mScrollEnabled != scrollEnabled) { 2368 mScrollEnabled = scrollEnabled; 2369 if (mScrollEnabled && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED 2370 && mFocusPosition != NO_POSITION) { 2371 scrollToSelection(mBaseGridView, mFocusPosition, true); 2372 } 2373 } 2374 } 2375 2376 public boolean isScrollEnabled() { 2377 return mScrollEnabled; 2378 } 2379 2380 private int findImmediateChildIndex(View view) { 2381 while (view != null && view != mBaseGridView) { 2382 int index = mBaseGridView.indexOfChild(view); 2383 if (index >= 0) { 2384 return index; 2385 } 2386 view = (View) view.getParent(); 2387 } 2388 return NO_POSITION; 2389 } 2390 2391 void setFocusSearchDisabled(boolean disabled) { 2392 mFocusSearchDisabled = disabled; 2393 } 2394 2395 boolean isFocusSearchDisabled() { 2396 return mFocusSearchDisabled; 2397 } 2398 2399 @Override 2400 public View onInterceptFocusSearch(View focused, int direction) { 2401 if (mFocusSearchDisabled) { 2402 return focused; 2403 } 2404 return null; 2405 } 2406 2407 boolean hasPreviousViewInSameRow(int pos) { 2408 if (mGrid == null || pos == NO_POSITION || mGrid.getFirstVisibleIndex() < 0) { 2409 return false; 2410 } 2411 if (mGrid.getFirstVisibleIndex() > 0) { 2412 return true; 2413 } 2414 final int focusedRow = mGrid.getLocation(pos).row; 2415 for (int i = getChildCount() - 1; i >= 0; i--) { 2416 int position = getPositionByIndex(i); 2417 Grid.Location loc = mGrid.getLocation(position); 2418 if (loc != null && loc.row == focusedRow) { 2419 if (position < pos) { 2420 return true; 2421 } 2422 } 2423 } 2424 return false; 2425 } 2426 2427 @Override 2428 public boolean onAddFocusables(RecyclerView recyclerView, 2429 ArrayList<View> views, int direction, int focusableMode) { 2430 if (mFocusSearchDisabled) { 2431 return true; 2432 } 2433 // If this viewgroup or one of its children currently has focus then we 2434 // consider our children for focus searching in main direction on the same row. 2435 // If this viewgroup has no focus and using focus align, we want the system 2436 // to ignore our children and pass focus to the viewgroup, which will pass 2437 // focus on to its children appropriately. 2438 // If this viewgroup has no focus and not using focus align, we want to 2439 // consider the child that does not overlap with padding area. 2440 if (recyclerView.hasFocus()) { 2441 final int movement = getMovement(direction); 2442 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2443 // Move on secondary direction uses default addFocusables(). 2444 return false; 2445 } 2446 if (mPendingMoveSmoothScroller != null) { 2447 // don't find next focusable if has pending movement. 2448 return true; 2449 } 2450 final View focused = recyclerView.findFocus(); 2451 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2452 // Add focusables of focused item. 2453 if (focusedPos != NO_POSITION) { 2454 findViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2455 } 2456 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2457 mGrid.getLocation(focusedPos).row : NO_POSITION; 2458 // Add focusables of next neighbor of same row on the focus search direction. 2459 if (mGrid != null) { 2460 final int focusableCount = views.size(); 2461 for (int i = 0, count = getChildCount(); i < count; i++) { 2462 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2463 final View child = getChildAt(index); 2464 if (child.getVisibility() != View.VISIBLE || !child.hasFocusable()) { 2465 continue; 2466 } 2467 int position = getPositionByIndex(index); 2468 Grid.Location loc = mGrid.getLocation(position); 2469 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2470 if (focusedPos == NO_POSITION || 2471 (movement == NEXT_ITEM && position > focusedPos) 2472 || (movement == PREV_ITEM && position < focusedPos)) { 2473 child.addFocusables(views, direction, focusableMode); 2474 if (views.size() > focusableCount) { 2475 break; 2476 } 2477 } 2478 } 2479 } 2480 } 2481 } else { 2482 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2483 // adding views not overlapping padding area to avoid scrolling in gaining focus 2484 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2485 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2486 int focusableCount = views.size(); 2487 for (int i = 0, count = getChildCount(); i < count; i++) { 2488 View child = getChildAt(i); 2489 if (child.getVisibility() == View.VISIBLE) { 2490 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2491 child.addFocusables(views, direction, focusableMode); 2492 } 2493 } 2494 } 2495 // if we cannot find any, then just add all children. 2496 if (views.size() == focusableCount) { 2497 for (int i = 0, count = getChildCount(); i < count; i++) { 2498 View child = getChildAt(i); 2499 if (child.getVisibility() == View.VISIBLE) { 2500 child.addFocusables(views, direction, focusableMode); 2501 } 2502 } 2503 if (views.size() != focusableCount) { 2504 return true; 2505 } 2506 } else { 2507 return true; 2508 } 2509 // if still cannot find any, fall through and add itself 2510 } 2511 if (recyclerView.isFocusable()) { 2512 views.add(recyclerView); 2513 } 2514 } 2515 return true; 2516 } 2517 2518 private boolean hasCreatedLastItem() { 2519 int count = mState.getItemCount(); 2520 return count == 0 || findViewByPosition(count - 1) != null; 2521 } 2522 2523 private boolean hasCreatedFirstItem() { 2524 int count = mState.getItemCount(); 2525 return count == 0 || findViewByPosition(0) != null; 2526 } 2527 2528 boolean canScrollTo(View view) { 2529 return view.getVisibility() == View.VISIBLE && (!hasFocus() || view.hasFocusable()); 2530 } 2531 2532 @Override 2533 public View onFocusSearchFailed(View focused, int direction, Recycler recycler, 2534 RecyclerView.State state) { 2535 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2536 2537 View view = null; 2538 int movement = getMovement(direction); 2539 final boolean isScroll = mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE; 2540 saveContext(recycler, state); 2541 if (movement == NEXT_ITEM) { 2542 if (isScroll || !mFocusOutEnd) { 2543 view = focused; 2544 } 2545 if (mScrollEnabled && !hasCreatedLastItem()) { 2546 processPendingMovement(true); 2547 view = focused; 2548 } 2549 } else if (movement == PREV_ITEM) { 2550 if (isScroll || !mFocusOutFront) { 2551 view = focused; 2552 } 2553 if (mScrollEnabled && !hasCreatedFirstItem()) { 2554 processPendingMovement(false); 2555 view = focused; 2556 } 2557 } 2558 leaveContext(); 2559 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed returning view " + view); 2560 return view; 2561 } 2562 2563 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2564 Rect previouslyFocusedRect) { 2565 switch (mFocusScrollStrategy) { 2566 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2567 default: 2568 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2569 direction, previouslyFocusedRect); 2570 case BaseGridView.FOCUS_SCROLL_PAGE: 2571 case BaseGridView.FOCUS_SCROLL_ITEM: 2572 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2573 direction, previouslyFocusedRect); 2574 } 2575 } 2576 2577 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2578 int direction, Rect previouslyFocusedRect) { 2579 View view = findViewByPosition(mFocusPosition); 2580 if (view != null) { 2581 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2582 if (!result && DEBUG) { 2583 Log.w(getTag(), "failed to request focus on " + view); 2584 } 2585 return result; 2586 } 2587 return false; 2588 } 2589 2590 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2591 int direction, Rect previouslyFocusedRect) { 2592 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2593 int index; 2594 int increment; 2595 int end; 2596 int count = getChildCount(); 2597 if ((direction & View.FOCUS_FORWARD) != 0) { 2598 index = 0; 2599 increment = 1; 2600 end = count; 2601 } else { 2602 index = count - 1; 2603 increment = -1; 2604 end = -1; 2605 } 2606 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2607 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2608 for (int i = index; i != end; i += increment) { 2609 View child = getChildAt(i); 2610 if (child.getVisibility() == View.VISIBLE) { 2611 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2612 if (child.requestFocus(direction, previouslyFocusedRect)) { 2613 return true; 2614 } 2615 } 2616 } 2617 } 2618 return false; 2619 } 2620 2621 private final static int PREV_ITEM = 0; 2622 private final static int NEXT_ITEM = 1; 2623 private final static int PREV_ROW = 2; 2624 private final static int NEXT_ROW = 3; 2625 2626 private int getMovement(int direction) { 2627 int movement = View.FOCUS_LEFT; 2628 2629 if (mOrientation == HORIZONTAL) { 2630 switch(direction) { 2631 case View.FOCUS_LEFT: 2632 movement = (!mReverseFlowPrimary) ? PREV_ITEM : NEXT_ITEM; 2633 break; 2634 case View.FOCUS_RIGHT: 2635 movement = (!mReverseFlowPrimary) ? NEXT_ITEM : PREV_ITEM; 2636 break; 2637 case View.FOCUS_UP: 2638 movement = PREV_ROW; 2639 break; 2640 case View.FOCUS_DOWN: 2641 movement = NEXT_ROW; 2642 break; 2643 } 2644 } else if (mOrientation == VERTICAL) { 2645 switch(direction) { 2646 case View.FOCUS_LEFT: 2647 movement = (!mReverseFlowPrimary) ? PREV_ROW : NEXT_ROW; 2648 break; 2649 case View.FOCUS_RIGHT: 2650 movement = (!mReverseFlowPrimary) ? NEXT_ROW : PREV_ROW; 2651 break; 2652 case View.FOCUS_UP: 2653 movement = PREV_ITEM; 2654 break; 2655 case View.FOCUS_DOWN: 2656 movement = NEXT_ITEM; 2657 break; 2658 } 2659 } 2660 2661 return movement; 2662 } 2663 2664 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2665 View view = findViewByPosition(mFocusPosition); 2666 if (view == null) { 2667 return i; 2668 } 2669 int focusIndex = recyclerView.indexOfChild(view); 2670 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2671 // drawing order is 0 1 2 3 9 8 7 6 5 4 2672 if (i < focusIndex) { 2673 return i; 2674 } else if (i < childCount - 1) { 2675 return focusIndex + childCount - 1 - i; 2676 } else { 2677 return focusIndex; 2678 } 2679 } 2680 2681 @Override 2682 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2683 RecyclerView.Adapter newAdapter) { 2684 if (DEBUG) Log.v(getTag(), "onAdapterChanged to " + newAdapter); 2685 if (oldAdapter != null) { 2686 discardLayoutInfo(); 2687 mFocusPosition = NO_POSITION; 2688 mFocusPositionOffset = 0; 2689 mChildrenStates.clear(); 2690 } 2691 super.onAdapterChanged(oldAdapter, newAdapter); 2692 } 2693 2694 private void discardLayoutInfo() { 2695 mGrid = null; 2696 mRowSizeSecondary = null; 2697 mRowSecondarySizeRefresh = false; 2698 } 2699 2700 public void setLayoutEnabled(boolean layoutEnabled) { 2701 if (mLayoutEnabled != layoutEnabled) { 2702 mLayoutEnabled = layoutEnabled; 2703 requestLayout(); 2704 } 2705 } 2706 2707 void setChildrenVisibility(int visiblity) { 2708 mChildVisibility = visiblity; 2709 if (mChildVisibility != -1) { 2710 int count = getChildCount(); 2711 for (int i= 0; i < count; i++) { 2712 getChildAt(i).setVisibility(mChildVisibility); 2713 } 2714 } 2715 } 2716 2717 final static class SavedState implements Parcelable { 2718 2719 int index; // index inside adapter of the current view 2720 Bundle childStates = Bundle.EMPTY; 2721 2722 @Override 2723 public void writeToParcel(Parcel out, int flags) { 2724 out.writeInt(index); 2725 out.writeBundle(childStates); 2726 } 2727 2728 @SuppressWarnings("hiding") 2729 public static final Parcelable.Creator<SavedState> CREATOR = 2730 new Parcelable.Creator<SavedState>() { 2731 @Override 2732 public SavedState createFromParcel(Parcel in) { 2733 return new SavedState(in); 2734 } 2735 2736 @Override 2737 public SavedState[] newArray(int size) { 2738 return new SavedState[size]; 2739 } 2740 }; 2741 2742 @Override 2743 public int describeContents() { 2744 return 0; 2745 } 2746 2747 SavedState(Parcel in) { 2748 index = in.readInt(); 2749 childStates = in.readBundle(GridLayoutManager.class.getClassLoader()); 2750 } 2751 2752 SavedState() { 2753 } 2754 } 2755 2756 @Override 2757 public Parcelable onSaveInstanceState() { 2758 if (DEBUG) Log.v(getTag(), "onSaveInstanceState getSelection() " + getSelection()); 2759 SavedState ss = new SavedState(); 2760 for (int i = 0, count = getChildCount(); i < count; i++) { 2761 View view = getChildAt(i); 2762 int position = getPositionByView(view); 2763 if (position != NO_POSITION) { 2764 mChildrenStates.saveOnScreenView(view, position); 2765 } 2766 } 2767 ss.index = getSelection(); 2768 ss.childStates = mChildrenStates.saveAsBundle(); 2769 return ss; 2770 } 2771 2772 void onChildRecycled(RecyclerView.ViewHolder holder) { 2773 final int position = holder.getAdapterPosition(); 2774 if (position != NO_POSITION) { 2775 mChildrenStates.saveOffscreenView(holder.itemView, position); 2776 } 2777 } 2778 2779 @Override 2780 public void onRestoreInstanceState(Parcelable state) { 2781 if (!(state instanceof SavedState)) { 2782 return; 2783 } 2784 SavedState loadingState = (SavedState)state; 2785 mFocusPosition = loadingState.index; 2786 mFocusPositionOffset = 0; 2787 mChildrenStates.loadFromBundle(loadingState.childStates); 2788 mForceFullLayout = true; 2789 requestLayout(); 2790 if (DEBUG) Log.v(getTag(), "onRestoreInstanceState mFocusPosition " + mFocusPosition); 2791 } 2792} 2793