GridLayoutManager.java revision c0b265dd2df42b399ba1f959b3dfd14dd14012b5
1/* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except 5 * in compliance with the License. You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software distributed under the License 10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express 11 * or implied. See the License for the specific language governing permissions and limitations under 12 * the License. 13 */ 14package android.support.v17.leanback.widget; 15 16import android.content.Context; 17import android.graphics.PointF; 18import android.graphics.Rect; 19import android.os.Bundle; 20import android.os.Parcel; 21import android.os.Parcelable; 22import android.support.v4.util.CircularIntArray; 23import android.support.v4.view.ViewCompat; 24import android.support.v7.widget.LinearSmoothScroller; 25import android.support.v7.widget.RecyclerView; 26import android.support.v7.widget.RecyclerView.Recycler; 27import android.support.v7.widget.RecyclerView.State; 28import android.support.v17.leanback.os.TraceHelper; 29 30import static android.support.v7.widget.RecyclerView.NO_ID; 31import static android.support.v7.widget.RecyclerView.NO_POSITION; 32import static android.support.v7.widget.RecyclerView.HORIZONTAL; 33import static android.support.v7.widget.RecyclerView.VERTICAL; 34 35import android.util.AttributeSet; 36import android.util.Log; 37import android.view.FocusFinder; 38import android.view.Gravity; 39import android.view.View; 40import android.view.ViewParent; 41import android.view.View.MeasureSpec; 42import android.view.ViewGroup.MarginLayoutParams; 43import android.view.ViewGroup; 44 45import java.io.PrintWriter; 46import java.io.StringWriter; 47import java.util.ArrayList; 48import java.util.List; 49 50final class GridLayoutManager extends RecyclerView.LayoutManager { 51 52 /* 53 * LayoutParams for {@link HorizontalGridView} and {@link VerticalGridView}. 54 * The class currently does two internal jobs: 55 * - Saves optical bounds insets. 56 * - Caches focus align view center. 57 */ 58 static class LayoutParams extends RecyclerView.LayoutParams { 59 60 // The view is saved only during animation. 61 private View mView; 62 63 // For placement 64 private int mLeftInset; 65 private int mTopInset; 66 private int mRightInset; 67 private int mBottomInset; 68 69 // For alignment 70 private int mAlignX; 71 private int mAlignY; 72 73 public LayoutParams(Context c, AttributeSet attrs) { 74 super(c, attrs); 75 } 76 77 public LayoutParams(int width, int height) { 78 super(width, height); 79 } 80 81 public LayoutParams(MarginLayoutParams source) { 82 super(source); 83 } 84 85 public LayoutParams(ViewGroup.LayoutParams source) { 86 super(source); 87 } 88 89 public LayoutParams(RecyclerView.LayoutParams source) { 90 super(source); 91 } 92 93 public LayoutParams(LayoutParams source) { 94 super(source); 95 } 96 97 int getAlignX() { 98 return mAlignX; 99 } 100 101 int getAlignY() { 102 return mAlignY; 103 } 104 105 int getOpticalLeft(View view) { 106 return view.getLeft() + mLeftInset; 107 } 108 109 int getOpticalTop(View view) { 110 return view.getTop() + mTopInset; 111 } 112 113 int getOpticalRight(View view) { 114 return view.getRight() - mRightInset; 115 } 116 117 int getOpticalBottom(View view) { 118 return view.getBottom() - mBottomInset; 119 } 120 121 int getOpticalWidth(View view) { 122 return view.getWidth() - mLeftInset - mRightInset; 123 } 124 125 int getOpticalHeight(View view) { 126 return view.getHeight() - mTopInset - mBottomInset; 127 } 128 129 int getOpticalLeftInset() { 130 return mLeftInset; 131 } 132 133 int getOpticalRightInset() { 134 return mRightInset; 135 } 136 137 int getOpticalTopInset() { 138 return mTopInset; 139 } 140 141 int getOpticalBottomInset() { 142 return mBottomInset; 143 } 144 145 void setAlignX(int alignX) { 146 mAlignX = alignX; 147 } 148 149 void setAlignY(int alignY) { 150 mAlignY = alignY; 151 } 152 153 void setOpticalInsets(int leftInset, int topInset, int rightInset, int bottomInset) { 154 mLeftInset = leftInset; 155 mTopInset = topInset; 156 mRightInset = rightInset; 157 mBottomInset = bottomInset; 158 } 159 160 private void invalidateItemDecoration() { 161 ViewParent parent = mView.getParent(); 162 if (parent instanceof RecyclerView) { 163 // TODO: we only need invalidate parent if it has ItemDecoration 164 ((RecyclerView) parent).invalidate(); 165 } 166 } 167 } 168 169 /** 170 * Base class which scrolls to selected view in onStop(). 171 */ 172 abstract class GridLinearSmoothScroller extends LinearSmoothScroller { 173 GridLinearSmoothScroller() { 174 super(mBaseGridView.getContext()); 175 } 176 177 @Override 178 protected void onStop() { 179 // onTargetFound() may not be called if we hit the "wall" first. 180 View targetView = findViewByPosition(getTargetPosition()); 181 if (hasFocus() && targetView != null) { 182 mInSelection = true; 183 targetView.requestFocus(); 184 mInSelection = false; 185 } 186 if (needsDispatchChildSelectedOnStop()) { 187 dispatchChildSelected(); 188 } 189 super.onStop(); 190 } 191 192 boolean needsDispatchChildSelectedOnStop() { 193 return true; 194 } 195 196 @Override 197 protected void onTargetFound(View targetView, 198 RecyclerView.State state, Action action) { 199 if (getScrollPosition(targetView, sTwoInts)) { 200 int dx, dy; 201 if (mOrientation == HORIZONTAL) { 202 dx = sTwoInts[0]; 203 dy = sTwoInts[1]; 204 } else { 205 dx = sTwoInts[1]; 206 dy = sTwoInts[0]; 207 } 208 final int distance = (int) Math.sqrt(dx * dx + dy * dy); 209 final int time = calculateTimeForDeceleration(distance); 210 action.update(dx, dy, time, mDecelerateInterpolator); 211 } 212 } 213 } 214 215 /** 216 * The SmoothScroller that remembers pending DPAD keys and consume pending keys 217 * during scroll. 218 */ 219 final class PendingMoveSmoothScroller extends GridLinearSmoothScroller { 220 // -2 is a target position that LinearSmoothScroller can never find until 221 // consumePendingMovesXXX() sets real targetPosition. 222 final static int TARGET_UNDEFINED = -2; 223 // whether the grid is staggered. 224 private final boolean mStaggeredGrid; 225 // Number of pending movements on primary direction, negative if PREV_ITEM. 226 private int mPendingMoves; 227 228 PendingMoveSmoothScroller(int initialPendingMoves, boolean staggeredGrid) { 229 mPendingMoves = initialPendingMoves; 230 mStaggeredGrid = staggeredGrid; 231 setTargetPosition(TARGET_UNDEFINED); 232 } 233 234 void increasePendingMoves() { 235 if (mPendingMoves < MAX_PENDING_MOVES) { 236 mPendingMoves++; 237 if (mPendingMoves == 0) { 238 dispatchChildSelected(); 239 } 240 } 241 } 242 243 void decreasePendingMoves() { 244 if (mPendingMoves > -MAX_PENDING_MOVES) { 245 mPendingMoves--; 246 if (mPendingMoves == 0) { 247 dispatchChildSelected(); 248 } 249 } 250 } 251 252 /** 253 * Called before laid out an item when non-staggered grid can handle pending movements 254 * by skipping "mNumRows" per movement; staggered grid will have to wait the item 255 * has been laid out in consumePendingMovesAfterLayout(). 256 */ 257 void consumePendingMovesBeforeLayout() { 258 if (mStaggeredGrid || mPendingMoves == 0) { 259 return; 260 } 261 View newSelected = null; 262 int startPos = mPendingMoves > 0 ? mFocusPosition + mNumRows : 263 mFocusPosition - mNumRows; 264 for (int pos = startPos; mPendingMoves != 0; 265 pos = mPendingMoves > 0 ? pos + mNumRows: pos - mNumRows) { 266 View v = findViewByPosition(pos); 267 if (v == null) { 268 break; 269 } 270 if (!canScrollTo(v)) { 271 continue; 272 } 273 newSelected = v; 274 mFocusPosition = pos; 275 if (mPendingMoves > 0) { 276 mPendingMoves--; 277 } else { 278 mPendingMoves++; 279 } 280 } 281 if (newSelected != null && hasFocus()) { 282 mInSelection = true; 283 newSelected.requestFocus(); 284 mInSelection = false; 285 } 286 } 287 288 /** 289 * Called after laid out an item. Staggered grid should find view on same 290 * Row and consume pending movements. 291 */ 292 void consumePendingMovesAfterLayout() { 293 if (mStaggeredGrid && mPendingMoves != 0) { 294 // consume pending moves, focus to item on the same row. 295 final int focusedRow = mGrid != null && mFocusPosition != NO_POSITION ? 296 mGrid.getLocation(mFocusPosition).row : NO_POSITION; 297 View newSelected = null; 298 for (int i = 0, count = getChildCount(); i < count && mPendingMoves != 0; i++) { 299 int index = mPendingMoves > 0 ? i : count - 1 - i; 300 final View child = getChildAt(index); 301 if (!canScrollTo(child)) { 302 continue; 303 } 304 int position = getPositionByIndex(index); 305 Grid.Location loc = mGrid.getLocation(position); 306 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 307 if (mFocusPosition == NO_POSITION) { 308 mFocusPosition = position; 309 newSelected = child; 310 } else if ((mPendingMoves > 0 && position > mFocusPosition) 311 || (mPendingMoves < 0 && position < mFocusPosition)) { 312 mFocusPosition = position; 313 if (mPendingMoves > 0) { 314 mPendingMoves--; 315 } else { 316 mPendingMoves++; 317 } 318 newSelected = child; 319 } 320 } 321 } 322 if (newSelected != null && hasFocus()) { 323 mInSelection = true; 324 newSelected.requestFocus(); 325 mInSelection = false; 326 } 327 if (mPendingMoves == 0) { 328 dispatchChildSelected(); 329 } 330 } 331 if (mPendingMoves == 0 || (mPendingMoves > 0 && hasCreatedLastItem()) 332 || (mPendingMoves < 0 && hasCreatedFirstItem())) { 333 setTargetPosition(mFocusPosition); 334 stop(); 335 } 336 } 337 338 @Override 339 protected void updateActionForInterimTarget(Action action) { 340 if (mPendingMoves == 0) { 341 return; 342 } 343 super.updateActionForInterimTarget(action); 344 } 345 346 @Override 347 public PointF computeScrollVectorForPosition(int targetPosition) { 348 if (mPendingMoves == 0) { 349 return null; 350 } 351 int direction = (mReverseFlowPrimary ? mPendingMoves > 0 : mPendingMoves < 0) ? 352 -1 : 1; 353 if (mOrientation == HORIZONTAL) { 354 return new PointF(direction, 0); 355 } else { 356 return new PointF(0, direction); 357 } 358 } 359 360 @Override 361 boolean needsDispatchChildSelectedOnStop() { 362 return mPendingMoves != 0; 363 } 364 365 @Override 366 protected void onStop() { 367 super.onStop(); 368 // if we hit wall, need clear the remaining pending moves. 369 mPendingMoves = 0; 370 mPendingMoveSmoothScroller = null; 371 View v = findViewByPosition(getTargetPosition()); 372 if (v != null) scrollToView(v, true); 373 } 374 }; 375 376 private static final String TAG = "GridLayoutManager"; 377 private static final boolean DEBUG = false; 378 private static final boolean TRACE = false; 379 380 // maximum pending movement in one direction. 381 private final static int MAX_PENDING_MOVES = 10; 382 383 private String getTag() { 384 return TAG + ":" + mBaseGridView.getId(); 385 } 386 387 private final BaseGridView mBaseGridView; 388 389 /** 390 * Note on conventions in the presence of RTL layout directions: 391 * Many properties and method names reference entities related to the 392 * beginnings and ends of things. In the presence of RTL flows, 393 * it may not be clear whether this is intended to reference a 394 * quantity that changes direction in RTL cases, or a quantity that 395 * does not. Here are the conventions in use: 396 * 397 * start/end: coordinate quantities - do reverse 398 * (optical) left/right: coordinate quantities - do not reverse 399 * low/high: coordinate quantities - do not reverse 400 * min/max: coordinate quantities - do not reverse 401 * scroll offset - coordinate quantities - do not reverse 402 * first/last: positional indices - do not reverse 403 * front/end: positional indices - do not reverse 404 * prepend/append: related to positional indices - do not reverse 405 * 406 * Note that although quantities do not reverse in RTL flows, their 407 * relationship does. In LTR flows, the first positional index is 408 * leftmost; in RTL flows, it is rightmost. Thus, anywhere that 409 * positional quantities are mapped onto coordinate quantities, 410 * the flow must be checked and the logic reversed. 411 */ 412 413 /** 414 * The orientation of a "row". 415 */ 416 private int mOrientation = HORIZONTAL; 417 418 private RecyclerView.State mState; 419 private RecyclerView.Recycler mRecycler; 420 421 private boolean mInLayout; 422 private boolean mInScroll; 423 private boolean mInFastRelayout; 424 /** 425 * During full layout pass, when GridView had focus: onLayoutChildren will 426 * skip non-focusable child and adjust mFocusPosition. 427 */ 428 private boolean mInLayoutSearchFocus; 429 private boolean mInSelection = false; 430 431 private OnChildSelectedListener mChildSelectedListener = null; 432 433 private OnChildLaidOutListener mChildLaidOutListener = null; 434 435 /** 436 * The focused position, it's not the currently visually aligned position 437 * but it is the final position that we intend to focus on. If there are 438 * multiple setSelection() called, mFocusPosition saves last value. 439 */ 440 private int mFocusPosition = NO_POSITION; 441 442 /** 443 * LinearSmoothScroller that consume pending DPAD movements. 444 */ 445 private PendingMoveSmoothScroller mPendingMoveSmoothScroller; 446 447 /** 448 * The offset to be applied to mFocusPosition, due to adapter change, on the next 449 * layout. Set to Integer.MIN_VALUE means item was removed. 450 * TODO: This is somewhat duplication of RecyclerView getOldPosition() which is 451 * unfortunately cleared after prelayout. 452 */ 453 private int mFocusPositionOffset = 0; 454 455 /** 456 * Extra pixels applied on primary direction. 457 */ 458 private int mPrimaryScrollExtra; 459 460 /** 461 * Force a full layout under certain situations. E.g. Rows change, jump to invisible child. 462 */ 463 private boolean mForceFullLayout; 464 465 /** 466 * True if layout is enabled. 467 */ 468 private boolean mLayoutEnabled = true; 469 470 /** 471 * override child visibility 472 */ 473 private int mChildVisibility = -1; 474 475 /** 476 * The scroll offsets of the viewport relative to the entire view. 477 */ 478 private int mScrollOffsetPrimary; 479 private int mScrollOffsetSecondary; 480 481 /** 482 * User-specified row height/column width. Can be WRAP_CONTENT. 483 */ 484 private int mRowSizeSecondaryRequested; 485 486 /** 487 * The fixed size of each grid item in the secondary direction. This corresponds to 488 * the row height, equal for all rows. Grid items may have variable length 489 * in the primary direction. 490 */ 491 private int mFixedRowSizeSecondary; 492 493 /** 494 * Tracks the secondary size of each row. 495 */ 496 private int[] mRowSizeSecondary; 497 498 /** 499 * Flag controlling whether the current/next layout should 500 * be updating the secondary size of rows. 501 */ 502 private boolean mRowSecondarySizeRefresh; 503 504 /** 505 * The maximum measured size of the view. 506 */ 507 private int mMaxSizeSecondary; 508 509 /** 510 * Margin between items. 511 */ 512 private int mHorizontalMargin; 513 /** 514 * Margin between items vertically. 515 */ 516 private int mVerticalMargin; 517 /** 518 * Margin in main direction. 519 */ 520 private int mMarginPrimary; 521 /** 522 * Margin in second direction. 523 */ 524 private int mMarginSecondary; 525 /** 526 * How to position child in secondary direction. 527 */ 528 private int mGravity = Gravity.START | Gravity.TOP; 529 /** 530 * The number of rows in the grid. 531 */ 532 private int mNumRows; 533 /** 534 * Number of rows requested, can be 0 to be determined by parent size and 535 * rowHeight. 536 */ 537 private int mNumRowsRequested = 1; 538 539 /** 540 * Saves grid information of each view. 541 */ 542 Grid mGrid; 543 544 /** 545 * Focus Scroll strategy. 546 */ 547 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 548 /** 549 * Defines how item view is aligned in the window. 550 */ 551 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 552 553 /** 554 * Defines how item view is aligned. 555 */ 556 private final ItemAlignment mItemAlignment = new ItemAlignment(); 557 558 /** 559 * Dimensions of the view, width or height depending on orientation. 560 */ 561 private int mSizePrimary; 562 563 /** 564 * Allow DPAD key to navigate out at the front of the View (where position = 0), 565 * default is false. 566 */ 567 private boolean mFocusOutFront; 568 569 /** 570 * Allow DPAD key to navigate out at the end of the view, default is false. 571 */ 572 private boolean mFocusOutEnd; 573 574 /** 575 * True if focus search is disabled. 576 */ 577 private boolean mFocusSearchDisabled; 578 579 /** 580 * True if prune child, might be disabled during transition. 581 */ 582 private boolean mPruneChild = true; 583 584 /** 585 * True if scroll content, might be disabled during transition. 586 */ 587 private boolean mScrollEnabled = true; 588 589 /** 590 * Temporary variable: an int array of length=2. 591 */ 592 private static int[] sTwoInts = new int[2]; 593 594 /** 595 * Set to true for RTL layout in horizontal orientation 596 */ 597 private boolean mReverseFlowPrimary = false; 598 599 /** 600 * Set to true for RTL layout in vertical orientation 601 */ 602 private boolean mReverseFlowSecondary = false; 603 604 /** 605 * Temporaries used for measuring. 606 */ 607 private int[] mMeasuredDimension = new int[2]; 608 609 final ViewsStateBundle mChildrenStates = new ViewsStateBundle(); 610 611 public GridLayoutManager(BaseGridView baseGridView) { 612 mBaseGridView = baseGridView; 613 } 614 615 public void setOrientation(int orientation) { 616 if (orientation != HORIZONTAL && orientation != VERTICAL) { 617 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 618 return; 619 } 620 621 mOrientation = orientation; 622 mWindowAlignment.setOrientation(orientation); 623 mItemAlignment.setOrientation(orientation); 624 mForceFullLayout = true; 625 } 626 627 public void onRtlPropertiesChanged(int layoutDirection) { 628 if (mOrientation == HORIZONTAL) { 629 mReverseFlowPrimary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 630 mReverseFlowSecondary = false; 631 } else { 632 mReverseFlowSecondary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 633 mReverseFlowPrimary = false; 634 } 635 mWindowAlignment.horizontal.setReversedFlow(layoutDirection == View.LAYOUT_DIRECTION_RTL); 636 } 637 638 public int getFocusScrollStrategy() { 639 return mFocusScrollStrategy; 640 } 641 642 public void setFocusScrollStrategy(int focusScrollStrategy) { 643 mFocusScrollStrategy = focusScrollStrategy; 644 } 645 646 public void setWindowAlignment(int windowAlignment) { 647 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 648 } 649 650 public int getWindowAlignment() { 651 return mWindowAlignment.mainAxis().getWindowAlignment(); 652 } 653 654 public void setWindowAlignmentOffset(int alignmentOffset) { 655 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 656 } 657 658 public int getWindowAlignmentOffset() { 659 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 660 } 661 662 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 663 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 664 } 665 666 public float getWindowAlignmentOffsetPercent() { 667 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 668 } 669 670 public void setItemAlignmentOffset(int alignmentOffset) { 671 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 672 updateChildAlignments(); 673 } 674 675 public int getItemAlignmentOffset() { 676 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 677 } 678 679 public void setItemAlignmentOffsetWithPadding(boolean withPadding) { 680 mItemAlignment.mainAxis().setItemAlignmentOffsetWithPadding(withPadding); 681 updateChildAlignments(); 682 } 683 684 public boolean isItemAlignmentOffsetWithPadding() { 685 return mItemAlignment.mainAxis().isItemAlignmentOffsetWithPadding(); 686 } 687 688 public void setItemAlignmentOffsetPercent(float offsetPercent) { 689 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 690 updateChildAlignments(); 691 } 692 693 public float getItemAlignmentOffsetPercent() { 694 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 695 } 696 697 public void setItemAlignmentViewId(int viewId) { 698 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 699 updateChildAlignments(); 700 } 701 702 public int getItemAlignmentViewId() { 703 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 704 } 705 706 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 707 mFocusOutFront = throughFront; 708 mFocusOutEnd = throughEnd; 709 } 710 711 public void setNumRows(int numRows) { 712 if (numRows < 0) throw new IllegalArgumentException(); 713 mNumRowsRequested = numRows; 714 } 715 716 /** 717 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 718 */ 719 public void setRowHeight(int height) { 720 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 721 mRowSizeSecondaryRequested = height; 722 } else { 723 throw new IllegalArgumentException("Invalid row height: " + height); 724 } 725 } 726 727 public void setItemMargin(int margin) { 728 mVerticalMargin = mHorizontalMargin = margin; 729 mMarginPrimary = mMarginSecondary = margin; 730 } 731 732 public void setVerticalMargin(int margin) { 733 if (mOrientation == HORIZONTAL) { 734 mMarginSecondary = mVerticalMargin = margin; 735 } else { 736 mMarginPrimary = mVerticalMargin = margin; 737 } 738 } 739 740 public void setHorizontalMargin(int margin) { 741 if (mOrientation == HORIZONTAL) { 742 mMarginPrimary = mHorizontalMargin = margin; 743 } else { 744 mMarginSecondary = mHorizontalMargin = margin; 745 } 746 } 747 748 public int getVerticalMargin() { 749 return mVerticalMargin; 750 } 751 752 public int getHorizontalMargin() { 753 return mHorizontalMargin; 754 } 755 756 public void setGravity(int gravity) { 757 mGravity = gravity; 758 } 759 760 protected boolean hasDoneFirstLayout() { 761 return mGrid != null; 762 } 763 764 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 765 mChildSelectedListener = listener; 766 } 767 768 void setOnChildLaidOutListener(OnChildLaidOutListener listener) { 769 mChildLaidOutListener = listener; 770 } 771 772 private int getPositionByView(View view) { 773 if (view == null) { 774 return NO_POSITION; 775 } 776 LayoutParams params = (LayoutParams) view.getLayoutParams(); 777 if (params == null || params.isItemRemoved()) { 778 // when item is removed, the position value can be any value. 779 return NO_POSITION; 780 } 781 return params.getViewPosition(); 782 } 783 784 private int getPositionByIndex(int index) { 785 return getPositionByView(getChildAt(index)); 786 } 787 788 private void dispatchChildSelected() { 789 if (mChildSelectedListener == null) { 790 return; 791 } 792 793 if (TRACE) TraceHelper.beginSection("onChildSelected"); 794 View view = mFocusPosition == NO_POSITION ? null : findViewByPosition(mFocusPosition); 795 if (view != null) { 796 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(view); 797 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 798 vh == null? NO_ID: vh.getItemId()); 799 } else { 800 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 801 } 802 if (TRACE) TraceHelper.endSection(); 803 804 // Children may request layout when a child selection event occurs (such as a change of 805 // padding on the current and previously selected rows). 806 // If in layout, a child requesting layout may have been laid out before the selection 807 // callback. 808 // If it was not, the child will be laid out after the selection callback. 809 // If so, the layout request will be honoured though the view system will emit a double- 810 // layout warning. 811 // If not in layout, we may be scrolling in which case the child layout request will be 812 // eaten by recyclerview. Post a requestLayout. 813 if (!mInLayout && !mBaseGridView.isLayoutRequested()) { 814 int childCount = getChildCount(); 815 for (int i = 0; i < childCount; i++) { 816 if (getChildAt(i).isLayoutRequested()) { 817 forceRequestLayout(); 818 break; 819 } 820 } 821 } 822 } 823 824 @Override 825 public boolean canScrollHorizontally() { 826 // We can scroll horizontally if we have horizontal orientation, or if 827 // we are vertical and have more than one column. 828 return mOrientation == HORIZONTAL || mNumRows > 1; 829 } 830 831 @Override 832 public boolean canScrollVertically() { 833 // We can scroll vertically if we have vertical orientation, or if we 834 // are horizontal and have more than one row. 835 return mOrientation == VERTICAL || mNumRows > 1; 836 } 837 838 @Override 839 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 840 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 841 ViewGroup.LayoutParams.WRAP_CONTENT); 842 } 843 844 @Override 845 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 846 return new LayoutParams(context, attrs); 847 } 848 849 @Override 850 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 851 if (lp instanceof LayoutParams) { 852 return new LayoutParams((LayoutParams) lp); 853 } else if (lp instanceof RecyclerView.LayoutParams) { 854 return new LayoutParams((RecyclerView.LayoutParams) lp); 855 } else if (lp instanceof MarginLayoutParams) { 856 return new LayoutParams((MarginLayoutParams) lp); 857 } else { 858 return new LayoutParams(lp); 859 } 860 } 861 862 protected View getViewForPosition(int position) { 863 return mRecycler.getViewForPosition(position); 864 } 865 866 final int getOpticalLeft(View v) { 867 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 868 } 869 870 final int getOpticalRight(View v) { 871 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 872 } 873 874 final int getOpticalTop(View v) { 875 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 876 } 877 878 final int getOpticalBottom(View v) { 879 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 880 } 881 882 private int getViewMin(View v) { 883 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 884 } 885 886 private int getViewMax(View v) { 887 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 888 } 889 890 private int getViewCenter(View view) { 891 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 892 } 893 894 private int getViewCenterSecondary(View view) { 895 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 896 } 897 898 private int getViewCenterX(View v) { 899 LayoutParams p = (LayoutParams) v.getLayoutParams(); 900 return p.getOpticalLeft(v) + p.getAlignX(); 901 } 902 903 private int getViewCenterY(View v) { 904 LayoutParams p = (LayoutParams) v.getLayoutParams(); 905 return p.getOpticalTop(v) + p.getAlignY(); 906 } 907 908 /** 909 * Save Recycler and State for convenience. Must be paired with leaveContext(). 910 */ 911 private void saveContext(Recycler recycler, State state) { 912 if (mRecycler != null || mState != null) { 913 Log.e(TAG, "Recycler information was not released, bug!"); 914 } 915 mRecycler = recycler; 916 mState = state; 917 } 918 919 /** 920 * Discard saved Recycler and State. 921 */ 922 private void leaveContext() { 923 mRecycler = null; 924 mState = null; 925 } 926 927 /** 928 * Re-initialize data structures for a data change or handling invisible 929 * selection. The method tries its best to preserve position information so 930 * that staggered grid looks same before and after re-initialize. 931 * @return true if can fastRelayout() 932 */ 933 private boolean layoutInit() { 934 boolean focusViewWasInTree = mGrid != null && mFocusPosition >= 0 935 && mFocusPosition >= mGrid.getFirstVisibleIndex() 936 && mFocusPosition <= mGrid.getLastVisibleIndex(); 937 final int newItemCount = mState.getItemCount(); 938 if (newItemCount == 0) { 939 mFocusPosition = NO_POSITION; 940 } else if (mFocusPosition >= newItemCount) { 941 mFocusPosition = newItemCount - 1; 942 } else if (mFocusPosition == NO_POSITION && newItemCount > 0) { 943 // if focus position is never set before, initialize it to 0 944 mFocusPosition = 0; 945 } 946 if (!mState.didStructureChange() && mGrid.getFirstVisibleIndex() >= 0 && 947 !mForceFullLayout && mGrid != null && mGrid.getNumRows() == mNumRows) { 948 updateScrollController(); 949 updateScrollSecondAxis(); 950 mGrid.setMargin(mMarginPrimary); 951 if (!focusViewWasInTree && mFocusPosition != NO_POSITION) { 952 mGrid.setStart(mFocusPosition); 953 } 954 return true; 955 } else { 956 mForceFullLayout = false; 957 int firstVisibleIndex = focusViewWasInTree ? mGrid.getFirstVisibleIndex() : 0; 958 959 if (mGrid == null || mNumRows != mGrid.getNumRows() || 960 mReverseFlowPrimary != mGrid.isReversedFlow()) { 961 mGrid = Grid.createStaggeredMultipleRows(mNumRows); 962 mGrid.setProvider(mGridProvider); 963 mGrid.setReversedFlow(mReverseFlowPrimary); 964 } 965 initScrollController(); 966 updateScrollSecondAxis(); 967 mGrid.setMargin(mMarginPrimary); 968 detachAndScrapAttachedViews(mRecycler); 969 mGrid.resetVisibleIndex(); 970 if (mFocusPosition == NO_POSITION) { 971 mBaseGridView.clearFocus(); 972 } 973 mWindowAlignment.mainAxis().invalidateScrollMin(); 974 mWindowAlignment.mainAxis().invalidateScrollMax(); 975 if (focusViewWasInTree && firstVisibleIndex <= mFocusPosition) { 976 // if focusView was in tree, we will add item from first visible item 977 mGrid.setStart(firstVisibleIndex); 978 } else { 979 // if focusView was not in tree, it's probably because focus position jumped 980 // far away from visible range, so use mFocusPosition as start 981 mGrid.setStart(mFocusPosition); 982 } 983 return false; 984 } 985 } 986 987 private int getRowSizeSecondary(int rowIndex) { 988 if (mFixedRowSizeSecondary != 0) { 989 return mFixedRowSizeSecondary; 990 } 991 if (mRowSizeSecondary == null) { 992 return 0; 993 } 994 return mRowSizeSecondary[rowIndex]; 995 } 996 997 private int getRowStartSecondary(int rowIndex) { 998 int start = 0; 999 // Iterate from left to right, which is a different index traversal 1000 // in RTL flow 1001 if (mReverseFlowSecondary) { 1002 for (int i = mNumRows-1; i > rowIndex; i--) { 1003 start += getRowSizeSecondary(i) + mMarginSecondary; 1004 } 1005 } else { 1006 for (int i = 0; i < rowIndex; i++) { 1007 start += getRowSizeSecondary(i) + mMarginSecondary; 1008 } 1009 } 1010 return start; 1011 } 1012 1013 private int getSizeSecondary() { 1014 int rightmostIndex = mReverseFlowSecondary ? 0 : mNumRows - 1; 1015 return getRowStartSecondary(rightmostIndex) + getRowSizeSecondary(rightmostIndex); 1016 } 1017 1018 private void measureScrapChild(int position, int widthSpec, int heightSpec, 1019 int[] measuredDimension) { 1020 View view = mRecycler.getViewForPosition(position); 1021 if (view != null) { 1022 LayoutParams p = (LayoutParams) view.getLayoutParams(); 1023 int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, 1024 getPaddingLeft() + getPaddingRight(), p.width); 1025 int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, 1026 getPaddingTop() + getPaddingBottom(), p.height); 1027 view.measure(childWidthSpec, childHeightSpec); 1028 measuredDimension[0] = view.getMeasuredWidth(); 1029 measuredDimension[1] = view.getMeasuredHeight(); 1030 mRecycler.recycleView(view); 1031 } 1032 } 1033 1034 private boolean processRowSizeSecondary(boolean measure) { 1035 if (mFixedRowSizeSecondary != 0) { 1036 return false; 1037 } 1038 1039 if (TRACE) TraceHelper.beginSection("processRowSizeSecondary"); 1040 CircularIntArray[] rows = mGrid == null ? null : mGrid.getItemPositionsInRows(); 1041 boolean changed = false; 1042 int scrapChildWidth = -1; 1043 int scrapChildHeight = -1; 1044 1045 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 1046 CircularIntArray row = rows == null ? null : rows[rowIndex]; 1047 final int rowItemsPairCount = row == null ? 0 : row.size(); 1048 int rowSize = -1; 1049 for (int rowItemPairIndex = 0; rowItemPairIndex < rowItemsPairCount; 1050 rowItemPairIndex += 2) { 1051 final int rowIndexStart = row.get(rowItemPairIndex); 1052 final int rowIndexEnd = row.get(rowItemPairIndex + 1); 1053 for (int i = rowIndexStart; i <= rowIndexEnd; i++) { 1054 final View view = findViewByPosition(i); 1055 if (view == null) { 1056 continue; 1057 } 1058 if (measure && view.isLayoutRequested()) { 1059 measureChild(view); 1060 } 1061 final int secondarySize = mOrientation == HORIZONTAL ? 1062 view.getMeasuredHeight() : view.getMeasuredWidth(); 1063 if (secondarySize > rowSize) { 1064 rowSize = secondarySize; 1065 } 1066 } 1067 } 1068 1069 final int itemCount = mState.getItemCount(); 1070 if (measure && rowSize < 0 && itemCount > 0) { 1071 if (scrapChildWidth < 0 && scrapChildHeight < 0) { 1072 int position; 1073 if (mFocusPosition == NO_POSITION) { 1074 position = 0; 1075 } else if (mFocusPosition >= itemCount) { 1076 position = itemCount - 1; 1077 } else { 1078 position = mFocusPosition; 1079 } 1080 measureScrapChild(position, 1081 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1082 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1083 mMeasuredDimension); 1084 scrapChildWidth = mMeasuredDimension[0]; 1085 scrapChildHeight = mMeasuredDimension[1]; 1086 if (DEBUG) Log.v(TAG, "measured scrap child: " + scrapChildWidth + 1087 " " + scrapChildHeight); 1088 } 1089 rowSize = mOrientation == HORIZONTAL ? scrapChildHeight : scrapChildWidth; 1090 } 1091 if (rowSize < 0) { 1092 rowSize = 0; 1093 } 1094 if (mRowSizeSecondary[rowIndex] != rowSize) { 1095 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 1096 ", " + rowSize); 1097 mRowSizeSecondary[rowIndex] = rowSize; 1098 changed = true; 1099 } 1100 } 1101 1102 if (TRACE) TraceHelper.endSection(); 1103 return changed; 1104 } 1105 1106 /** 1107 * Checks if we need to update row secondary sizes. 1108 */ 1109 private void updateRowSecondarySizeRefresh() { 1110 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 1111 if (mRowSecondarySizeRefresh) { 1112 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 1113 forceRequestLayout(); 1114 } 1115 } 1116 1117 private void forceRequestLayout() { 1118 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 1119 // RecyclerView prevents us from requesting layout in many cases 1120 // (during layout, during scroll, etc.) 1121 // For secondary row size wrap_content support we currently need a 1122 // second layout pass to update the measured size after having measured 1123 // and added child views in layoutChildren. 1124 // Force the second layout by posting a delayed runnable. 1125 // TODO: investigate allowing a second layout pass, 1126 // or move child add/measure logic to the measure phase. 1127 ViewCompat.postOnAnimation(mBaseGridView, mRequestLayoutRunnable); 1128 } 1129 1130 private final Runnable mRequestLayoutRunnable = new Runnable() { 1131 @Override 1132 public void run() { 1133 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 1134 requestLayout(); 1135 } 1136 }; 1137 1138 @Override 1139 public void onMeasure(Recycler recycler, State state, int widthSpec, int heightSpec) { 1140 saveContext(recycler, state); 1141 1142 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 1143 int measuredSizeSecondary; 1144 if (mOrientation == HORIZONTAL) { 1145 sizePrimary = MeasureSpec.getSize(widthSpec); 1146 sizeSecondary = MeasureSpec.getSize(heightSpec); 1147 modeSecondary = MeasureSpec.getMode(heightSpec); 1148 paddingSecondary = getPaddingTop() + getPaddingBottom(); 1149 } else { 1150 sizeSecondary = MeasureSpec.getSize(widthSpec); 1151 sizePrimary = MeasureSpec.getSize(heightSpec); 1152 modeSecondary = MeasureSpec.getMode(widthSpec); 1153 paddingSecondary = getPaddingLeft() + getPaddingRight(); 1154 } 1155 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 1156 " heightSpec " + Integer.toHexString(heightSpec) + 1157 " modeSecondary " + Integer.toHexString(modeSecondary) + 1158 " sizeSecondary " + sizeSecondary + " " + this); 1159 1160 mMaxSizeSecondary = sizeSecondary; 1161 1162 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 1163 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1164 mFixedRowSizeSecondary = 0; 1165 1166 if (mRowSizeSecondary == null || mRowSizeSecondary.length != mNumRows) { 1167 mRowSizeSecondary = new int[mNumRows]; 1168 } 1169 1170 // Measure all current children and update cached row heights 1171 processRowSizeSecondary(true); 1172 1173 switch (modeSecondary) { 1174 case MeasureSpec.UNSPECIFIED: 1175 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 1176 break; 1177 case MeasureSpec.AT_MOST: 1178 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 1179 mMaxSizeSecondary); 1180 break; 1181 case MeasureSpec.EXACTLY: 1182 measuredSizeSecondary = mMaxSizeSecondary; 1183 break; 1184 default: 1185 throw new IllegalStateException("wrong spec"); 1186 } 1187 1188 } else { 1189 switch (modeSecondary) { 1190 case MeasureSpec.UNSPECIFIED: 1191 if (mRowSizeSecondaryRequested == 0) { 1192 if (mOrientation == HORIZONTAL) { 1193 throw new IllegalStateException("Must specify rowHeight or view height"); 1194 } else { 1195 throw new IllegalStateException("Must specify columnWidth or view width"); 1196 } 1197 } 1198 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1199 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1200 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1201 * (mNumRows - 1) + paddingSecondary; 1202 break; 1203 case MeasureSpec.AT_MOST: 1204 case MeasureSpec.EXACTLY: 1205 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 1206 mNumRows = 1; 1207 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 1208 } else if (mNumRowsRequested == 0) { 1209 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1210 mNumRows = (sizeSecondary + mMarginSecondary) 1211 / (mRowSizeSecondaryRequested + mMarginSecondary); 1212 } else if (mRowSizeSecondaryRequested == 0) { 1213 mNumRows = mNumRowsRequested; 1214 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 1215 * (mNumRows - 1)) / mNumRows; 1216 } else { 1217 mNumRows = mNumRowsRequested; 1218 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1219 } 1220 measuredSizeSecondary = sizeSecondary; 1221 if (modeSecondary == MeasureSpec.AT_MOST) { 1222 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1223 * (mNumRows - 1) + paddingSecondary; 1224 if (childrenSize < measuredSizeSecondary) { 1225 measuredSizeSecondary = childrenSize; 1226 } 1227 } 1228 break; 1229 default: 1230 throw new IllegalStateException("wrong spec"); 1231 } 1232 } 1233 if (mOrientation == HORIZONTAL) { 1234 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1235 } else { 1236 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1237 } 1238 if (DEBUG) { 1239 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1240 " measuredSizeSecondary " + measuredSizeSecondary + 1241 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1242 " mNumRows " + mNumRows); 1243 } 1244 leaveContext(); 1245 } 1246 1247 private void measureChild(View child) { 1248 if (TRACE) TraceHelper.beginSection("measureChild"); 1249 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1250 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1251 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1252 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1253 int widthSpec, heightSpec; 1254 1255 if (mOrientation == HORIZONTAL) { 1256 widthSpec = ViewGroup.getChildMeasureSpec( 1257 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1258 0, lp.width); 1259 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1260 } else { 1261 heightSpec = ViewGroup.getChildMeasureSpec( 1262 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1263 0, lp.height); 1264 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1265 } 1266 child.measure(widthSpec, heightSpec); 1267 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1268 " widthSpec " + Integer.toHexString(widthSpec) + 1269 " heightSpec " + Integer.toHexString(heightSpec) + 1270 " measuredWidth " + child.getMeasuredWidth() + 1271 " measuredHeight " + child.getMeasuredHeight()); 1272 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1273 if (TRACE) TraceHelper.endSection(); 1274 } 1275 1276 private Grid.Provider mGridProvider = new Grid.Provider() { 1277 1278 @Override 1279 public int getCount() { 1280 return mState.getItemCount(); 1281 } 1282 1283 @Override 1284 public int createItem(int index, boolean append, Object[] item) { 1285 if (TRACE) TraceHelper.beginSection("createItem"); 1286 if (TRACE) TraceHelper.beginSection("getview"); 1287 View v = getViewForPosition(index); 1288 if (TRACE) TraceHelper.endSection(); 1289 // See recyclerView docs: we don't need re-add scraped view if it was removed. 1290 if (!((RecyclerView.LayoutParams) v.getLayoutParams()).isItemRemoved()) { 1291 if (TRACE) TraceHelper.beginSection("addView"); 1292 if (append) { 1293 addView(v); 1294 } else { 1295 addView(v, 0); 1296 } 1297 if (TRACE) TraceHelper.endSection(); 1298 if (mChildVisibility != -1) { 1299 v.setVisibility(mChildVisibility); 1300 } 1301 1302 if (mPendingMoveSmoothScroller != null) { 1303 mPendingMoveSmoothScroller.consumePendingMovesBeforeLayout(); 1304 } 1305 if (!mInLayout) { 1306 // when we are appending item during scroll pass and the item's position 1307 // matches the mFocusPosition, we should signal a childSelected event. 1308 // However if we are still running PendingMoveSmoothScroller, we defer and 1309 // signal the event in PendingMoveSmoothScroller.onStop(). This can 1310 // avoid lots of childSelected events during a long smooth scrolling and 1311 // increase performance. 1312 if (index == mFocusPosition && (mPendingMoveSmoothScroller == null 1313 || mPendingMoveSmoothScroller.mPendingMoves == 0)) { 1314 dispatchChildSelected(); 1315 } 1316 } else if (!mInFastRelayout) { 1317 // fastRelayout will dispatch event at end of onLayoutChildren(). 1318 // For full layout, two situations here: 1319 // 1. mInLayoutSearchFocus is false, dispatchChildSelected() at mFocusPosition. 1320 // 2. mInLayoutSearchFocus is true: dispatchChildSelected() on first child 1321 // equal to or after mFocusPosition that can take focus. 1322 if (!mInLayoutSearchFocus && index == mFocusPosition) { 1323 dispatchChildSelected(); 1324 } else if (mInLayoutSearchFocus && index >= mFocusPosition 1325 && v.hasFocusable()) { 1326 mFocusPosition = index; 1327 mInLayoutSearchFocus = false; 1328 dispatchChildSelected(); 1329 } 1330 } 1331 measureChild(v); 1332 } 1333 item[0] = v; 1334 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1335 } 1336 1337 @Override 1338 public void addItem(Object item, int index, int length, int rowIndex, int edge) { 1339 View v = (View) item; 1340 int start, end; 1341 if (edge == Integer.MIN_VALUE || edge == Integer.MAX_VALUE) { 1342 edge = !mGrid.isReversedFlow() ? mWindowAlignment.mainAxis().getPaddingLow() 1343 : mWindowAlignment.mainAxis().getSize() 1344 - mWindowAlignment.mainAxis().getPaddingHigh(); 1345 } 1346 boolean edgeIsMin = !mGrid.isReversedFlow(); 1347 if (edgeIsMin) { 1348 start = edge; 1349 end = edge + length; 1350 } else { 1351 start = edge - length; 1352 end = edge; 1353 } 1354 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1355 mChildrenStates.loadView(v, index); 1356 layoutChild(rowIndex, v, start, end, startSecondary); 1357 if (DEBUG) { 1358 Log.d(getTag(), "addView " + index + " " + v); 1359 } 1360 if (TRACE) TraceHelper.endSection(); 1361 1362 if (index == mGrid.getFirstVisibleIndex()) { 1363 if (!mGrid.isReversedFlow()) { 1364 updateScrollMin(); 1365 } else { 1366 updateScrollMax(); 1367 } 1368 } 1369 if (index == mGrid.getLastVisibleIndex()) { 1370 if (!mGrid.isReversedFlow()) { 1371 updateScrollMax(); 1372 } else { 1373 updateScrollMin(); 1374 } 1375 } 1376 if (!mInLayout && mPendingMoveSmoothScroller != null) { 1377 mPendingMoveSmoothScroller.consumePendingMovesAfterLayout(); 1378 } 1379 if (mChildLaidOutListener != null) { 1380 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(v); 1381 mChildLaidOutListener.onChildLaidOut(mBaseGridView, v, index, 1382 vh == null ? NO_ID : vh.getItemId()); 1383 } 1384 } 1385 1386 @Override 1387 public void removeItem(int index) { 1388 if (TRACE) TraceHelper.beginSection("removeItem"); 1389 View v = findViewByPosition(index); 1390 if (mInLayout) { 1391 detachAndScrapView(v, mRecycler); 1392 } else { 1393 removeAndRecycleView(v, mRecycler); 1394 } 1395 if (TRACE) TraceHelper.endSection(); 1396 } 1397 1398 @Override 1399 public int getEdge(int index) { 1400 if (mReverseFlowPrimary) { 1401 return getViewMax(findViewByPosition(index)); 1402 } else { 1403 return getViewMin(findViewByPosition(index)); 1404 } 1405 } 1406 1407 @Override 1408 public int getSize(int index) { 1409 final View v = findViewByPosition(index); 1410 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1411 } 1412 }; 1413 1414 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1415 if (TRACE) TraceHelper.beginSection("layoutChild"); 1416 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1417 : v.getMeasuredWidth(); 1418 if (mFixedRowSizeSecondary > 0) { 1419 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1420 } 1421 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1422 final int horizontalGravity = (mReverseFlowPrimary || mReverseFlowSecondary) ? 1423 Gravity.getAbsoluteGravity(mGravity & Gravity.RELATIVE_HORIZONTAL_GRAVITY_MASK, View.LAYOUT_DIRECTION_RTL) : 1424 mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1425 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1426 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1427 // do nothing 1428 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1429 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1430 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1431 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1432 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1433 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1434 } 1435 int left, top, right, bottom; 1436 if (mOrientation == HORIZONTAL) { 1437 left = start; 1438 top = startSecondary; 1439 right = end; 1440 bottom = startSecondary + sizeSecondary; 1441 } else { 1442 top = start; 1443 left = startSecondary; 1444 bottom = end; 1445 right = startSecondary + sizeSecondary; 1446 } 1447 v.layout(left, top, right, bottom); 1448 updateChildOpticalInsets(v, left, top, right, bottom); 1449 updateChildAlignments(v); 1450 if (TRACE) TraceHelper.endSection(); 1451 } 1452 1453 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1454 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1455 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1456 v.getRight() - right, v.getBottom() - bottom); 1457 } 1458 1459 private void updateChildAlignments(View v) { 1460 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1461 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1462 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1463 } 1464 1465 private void updateChildAlignments() { 1466 for (int i = 0, c = getChildCount(); i < c; i++) { 1467 updateChildAlignments(getChildAt(i)); 1468 } 1469 } 1470 1471 private void removeInvisibleViewsAtEnd() { 1472 if (mPruneChild) { 1473 mGrid.removeInvisibleItemsAtEnd(mFocusPosition, 1474 mReverseFlowPrimary ? 0 : mSizePrimary); 1475 } 1476 } 1477 1478 private void removeInvisibleViewsAtFront() { 1479 if (mPruneChild) { 1480 mGrid.removeInvisibleItemsAtFront(mFocusPosition, 1481 mReverseFlowPrimary ? mSizePrimary : 0); 1482 } 1483 } 1484 1485 private boolean appendOneColumnVisibleItems() { 1486 return mGrid.appendOneColumnVisibleItems(); 1487 } 1488 1489 private boolean prependOneColumnVisibleItems() { 1490 return mGrid.prependOneColumnVisibleItems(); 1491 } 1492 1493 private void appendVisibleItems() { 1494 mGrid.appendVisibleItems(mReverseFlowPrimary ? 0 : mSizePrimary); 1495 } 1496 1497 private void prependVisibleItems() { 1498 mGrid.prependVisibleItems(mReverseFlowPrimary ? mSizePrimary : 0); 1499 } 1500 1501 /** 1502 * Fast layout when there is no structure change, adapter change, etc. 1503 * It will layout all views was layout requested or updated, until hit a view 1504 * with different size, then it break and detachAndScrap all views after that. 1505 */ 1506 private void fastRelayout() { 1507 boolean invalidateAfter = false; 1508 final int childCount = getChildCount(); 1509 int position = -1; 1510 for (int index = 0; index < childCount; index++) { 1511 View view = getChildAt(index); 1512 position = getPositionByIndex(index); 1513 Grid.Location location = mGrid.getLocation(position); 1514 if (location == null) { 1515 if (DEBUG) Log.w(getTag(), "fastRelayout(): no Location at " + position); 1516 invalidateAfter = true; 1517 break; 1518 } 1519 1520 int startSecondary = getRowStartSecondary(location.row) - mScrollOffsetSecondary; 1521 int primarySize, end; 1522 int start = getViewMin(view); 1523 int oldPrimarySize = (mOrientation == HORIZONTAL) ? 1524 view.getMeasuredWidth() : 1525 view.getMeasuredHeight(); 1526 1527 LayoutParams lp = (LayoutParams) view.getLayoutParams(); 1528 if (lp.viewNeedsUpdate()) { 1529 int viewIndex = mBaseGridView.indexOfChild(view); 1530 detachAndScrapView(view, mRecycler); 1531 view = getViewForPosition(position); 1532 addView(view, viewIndex); 1533 } 1534 1535 if (view.isLayoutRequested()) { 1536 measureChild(view); 1537 } 1538 if (mOrientation == HORIZONTAL) { 1539 primarySize = view.getMeasuredWidth(); 1540 end = start + primarySize; 1541 } else { 1542 primarySize = view.getMeasuredHeight(); 1543 end = start + primarySize; 1544 } 1545 layoutChild(location.row, view, start, end, startSecondary); 1546 if (oldPrimarySize != primarySize) { 1547 // size changed invalidate remaining Locations 1548 if (DEBUG) Log.d(getTag(), "fastRelayout: view size changed at " + position); 1549 invalidateAfter = true; 1550 break; 1551 } 1552 } 1553 if (invalidateAfter) { 1554 final int savedLastPos = mGrid.getLastVisibleIndex(); 1555 mGrid.invalidateItemsAfter(position); 1556 if (mPruneChild) { 1557 // in regular prune child mode, we just append items up to edge limit 1558 appendVisibleItems(); 1559 if (mFocusPosition >= 0 && mFocusPosition <= savedLastPos) { 1560 // make sure add focus view back: the view might be outside edge limit 1561 // when there is delta in onLayoutChildren(). 1562 while (mGrid.getLastVisibleIndex() < mFocusPosition) { 1563 mGrid.appendOneColumnVisibleItems(); 1564 } 1565 } 1566 } else { 1567 // prune disabled(e.g. in RowsFragment transition): append all removed items 1568 while (mGrid.appendOneColumnVisibleItems() 1569 && mGrid.getLastVisibleIndex() < savedLastPos); 1570 } 1571 } 1572 updateScrollMin(); 1573 updateScrollMax(); 1574 updateScrollSecondAxis(); 1575 } 1576 1577 public void removeAndRecycleAllViews(RecyclerView.Recycler recycler) { 1578 if (TRACE) TraceHelper.beginSection("removeAndRecycleAllViews"); 1579 if (DEBUG) Log.v(TAG, "removeAndRecycleAllViews " + getChildCount()); 1580 for (int i = getChildCount() - 1; i >= 0; i--) { 1581 removeAndRecycleViewAt(i, recycler); 1582 } 1583 if (TRACE) TraceHelper.endSection(); 1584 } 1585 1586 // Lays out items based on the current scroll position 1587 @Override 1588 public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) { 1589 if (DEBUG) { 1590 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1591 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1592 + " inPreLayout " + state.isPreLayout() 1593 + " didStructureChange " + state.didStructureChange() 1594 + " mForceFullLayout " + mForceFullLayout); 1595 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1596 } 1597 1598 if (mNumRows == 0) { 1599 // haven't done measure yet 1600 return; 1601 } 1602 final int itemCount = state.getItemCount(); 1603 if (itemCount < 0) { 1604 return; 1605 } 1606 1607 if (!mLayoutEnabled) { 1608 discardLayoutInfo(); 1609 removeAndRecycleAllViews(recycler); 1610 return; 1611 } 1612 mInLayout = true; 1613 1614 final boolean scrollToFocus = !isSmoothScrolling() 1615 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED; 1616 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1617 mFocusPosition = mFocusPosition + mFocusPositionOffset; 1618 mFocusPositionOffset = 0; 1619 } 1620 saveContext(recycler, state); 1621 1622 // Track the old focus view so we can adjust our system scroll position 1623 // so that any scroll animations happening now will remain valid. 1624 // We must use same delta in Pre Layout (if prelayout exists) and second layout. 1625 // So we cache the deltas in PreLayout and use it in second layout. 1626 int delta = 0, deltaSecondary = 0; 1627 if (mFocusPosition != NO_POSITION && scrollToFocus 1628 && mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE) { 1629 // FIXME: we should get the remaining scroll animation offset from RecyclerView 1630 View focusView = findViewByPosition(mFocusPosition); 1631 if (focusView != null) { 1632 delta = mWindowAlignment.mainAxis().getSystemScrollPos(mScrollOffsetPrimary 1633 + getViewCenter(focusView), false, false) - mScrollOffsetPrimary; 1634 deltaSecondary = mWindowAlignment.secondAxis().getSystemScrollPos( 1635 mScrollOffsetSecondary + getViewCenterSecondary(focusView), 1636 false, false) - mScrollOffsetSecondary; 1637 } 1638 } 1639 1640 boolean hadFocus = mBaseGridView.hasFocus(); 1641 int savedFocusPos = mFocusPosition; 1642 if (mInFastRelayout = layoutInit()) { 1643 fastRelayout(); 1644 // appends items till focus position. 1645 if (mFocusPosition != NO_POSITION) { 1646 View focusView = findViewByPosition(mFocusPosition); 1647 if (focusView != null) { 1648 if (scrollToFocus) { 1649 scrollToView(focusView, false); 1650 } 1651 if (hadFocus && !focusView.hasFocus()) { 1652 focusView.requestFocus(); 1653 } 1654 } 1655 } 1656 } else { 1657 mInLayoutSearchFocus = hadFocus; 1658 if (mFocusPosition != NO_POSITION) { 1659 // appends items till focus position. 1660 while (appendOneColumnVisibleItems() 1661 && findViewByPosition(mFocusPosition) == null) ; 1662 } 1663 // multiple rounds: scrollToView of first round may drag first/last child into 1664 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1665 int oldFirstVisible; 1666 int oldLastVisible; 1667 do { 1668 updateScrollMin(); 1669 updateScrollMax(); 1670 oldFirstVisible = mGrid.getFirstVisibleIndex(); 1671 oldLastVisible = mGrid.getLastVisibleIndex(); 1672 View focusView = findViewByPosition(mFocusPosition); 1673 // we need force to initialize the child view's position 1674 scrollToView(focusView, false); 1675 if (focusView != null && hadFocus && !focusView.hasFocus()) { 1676 focusView.requestFocus(); 1677 } 1678 appendVisibleItems(); 1679 prependVisibleItems(); 1680 removeInvisibleViewsAtFront(); 1681 removeInvisibleViewsAtEnd(); 1682 } while (mGrid.getFirstVisibleIndex() != oldFirstVisible || 1683 mGrid.getLastVisibleIndex() != oldLastVisible); 1684 } 1685 1686 if (scrollToFocus) { 1687 scrollDirectionPrimary(-delta); 1688 scrollDirectionSecondary(-deltaSecondary); 1689 } 1690 appendVisibleItems(); 1691 prependVisibleItems(); 1692 removeInvisibleViewsAtFront(); 1693 removeInvisibleViewsAtEnd(); 1694 1695 if (DEBUG) { 1696 StringWriter sw = new StringWriter(); 1697 PrintWriter pw = new PrintWriter(sw); 1698 mGrid.debugPrint(pw); 1699 Log.d(getTag(), sw.toString()); 1700 } 1701 1702 if (mRowSecondarySizeRefresh) { 1703 mRowSecondarySizeRefresh = false; 1704 } else { 1705 updateRowSecondarySizeRefresh(); 1706 } 1707 1708 // For fastRelayout, only dispatch event when focus position changes. 1709 if (mInFastRelayout && mFocusPosition != savedFocusPos) { 1710 dispatchChildSelected(); 1711 } else if (!mInFastRelayout && mInLayoutSearchFocus) { 1712 // For full layout we dispatchChildSelected() in createItem() unless searched all 1713 // children and found none is focusable then dispatchChildSelected() here. 1714 dispatchChildSelected(); 1715 } 1716 1717 mInLayout = false; 1718 leaveContext(); 1719 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1720 } 1721 1722 private void offsetChildrenSecondary(int increment) { 1723 final int childCount = getChildCount(); 1724 if (mOrientation == HORIZONTAL) { 1725 for (int i = 0; i < childCount; i++) { 1726 getChildAt(i).offsetTopAndBottom(increment); 1727 } 1728 } else { 1729 for (int i = 0; i < childCount; i++) { 1730 getChildAt(i).offsetLeftAndRight(increment); 1731 } 1732 } 1733 } 1734 1735 private void offsetChildrenPrimary(int increment) { 1736 final int childCount = getChildCount(); 1737 if (mOrientation == VERTICAL) { 1738 for (int i = 0; i < childCount; i++) { 1739 getChildAt(i).offsetTopAndBottom(increment); 1740 } 1741 } else { 1742 for (int i = 0; i < childCount; i++) { 1743 getChildAt(i).offsetLeftAndRight(increment); 1744 } 1745 } 1746 } 1747 1748 @Override 1749 public int scrollHorizontallyBy(int dx, Recycler recycler, RecyclerView.State state) { 1750 if (DEBUG) Log.v(getTag(), "scrollHorizontallyBy " + dx); 1751 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1752 return 0; 1753 } 1754 saveContext(recycler, state); 1755 mInScroll = true; 1756 int result; 1757 if (mOrientation == HORIZONTAL) { 1758 result = scrollDirectionPrimary(dx); 1759 } else { 1760 result = scrollDirectionSecondary(dx); 1761 } 1762 leaveContext(); 1763 mInScroll = false; 1764 return result; 1765 } 1766 1767 @Override 1768 public int scrollVerticallyBy(int dy, Recycler recycler, RecyclerView.State state) { 1769 if (DEBUG) Log.v(getTag(), "scrollVerticallyBy " + dy); 1770 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1771 return 0; 1772 } 1773 mInScroll = true; 1774 saveContext(recycler, state); 1775 int result; 1776 if (mOrientation == VERTICAL) { 1777 result = scrollDirectionPrimary(dy); 1778 } else { 1779 result = scrollDirectionSecondary(dy); 1780 } 1781 leaveContext(); 1782 mInScroll = false; 1783 return result; 1784 } 1785 1786 // scroll in main direction may add/prune views 1787 private int scrollDirectionPrimary(int da) { 1788 if (TRACE) TraceHelper.beginSection("scrollPrimary"); 1789 boolean isMaxUnknown = false, isMinUnknown = false; 1790 int minScroll = 0, maxScroll = 0; 1791 if (da > 0) { 1792 isMaxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1793 if (!isMaxUnknown) { 1794 maxScroll = mWindowAlignment.mainAxis().getMaxScroll(); 1795 if (mScrollOffsetPrimary + da > maxScroll) { 1796 da = maxScroll - mScrollOffsetPrimary; 1797 } 1798 } 1799 } else if (da < 0) { 1800 isMinUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1801 if (!isMinUnknown) { 1802 minScroll = mWindowAlignment.mainAxis().getMinScroll(); 1803 if (mScrollOffsetPrimary + da < minScroll) { 1804 da = minScroll - mScrollOffsetPrimary; 1805 } 1806 } 1807 } 1808 if (da == 0) { 1809 if (TRACE) TraceHelper.endSection(); 1810 return 0; 1811 } 1812 offsetChildrenPrimary(-da); 1813 mScrollOffsetPrimary += da; 1814 if (mInLayout) { 1815 if (TRACE) TraceHelper.endSection(); 1816 return da; 1817 } 1818 1819 int childCount = getChildCount(); 1820 boolean updated; 1821 1822 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1823 prependVisibleItems(); 1824 } else { 1825 appendVisibleItems(); 1826 } 1827 updated = getChildCount() > childCount; 1828 childCount = getChildCount(); 1829 1830 if (TRACE) TraceHelper.beginSection("remove"); 1831 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1832 removeInvisibleViewsAtEnd(); 1833 } else { 1834 removeInvisibleViewsAtFront(); 1835 } 1836 if (TRACE) TraceHelper.endSection(); 1837 updated |= getChildCount() < childCount; 1838 if (updated) { 1839 updateRowSecondarySizeRefresh(); 1840 } 1841 1842 mBaseGridView.invalidate(); 1843 if (TRACE) TraceHelper.endSection(); 1844 return da; 1845 } 1846 1847 // scroll in second direction will not add/prune views 1848 private int scrollDirectionSecondary(int dy) { 1849 if (dy == 0) { 1850 return 0; 1851 } 1852 offsetChildrenSecondary(-dy); 1853 mScrollOffsetSecondary += dy; 1854 mBaseGridView.invalidate(); 1855 return dy; 1856 } 1857 1858 private void updateScrollMax() { 1859 int highVisiblePos = (!mReverseFlowPrimary) ? mGrid.getLastVisibleIndex() 1860 : mGrid.getFirstVisibleIndex(); 1861 int highMaxPos = (!mReverseFlowPrimary) ? mState.getItemCount() - 1 : 0; 1862 if (highVisiblePos < 0) { 1863 return; 1864 } 1865 final boolean highAvailable = highVisiblePos == highMaxPos; 1866 final boolean maxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1867 if (!highAvailable && maxUnknown) { 1868 return; 1869 } 1870 int maxEdge = mGrid.findRowMax(true, sTwoInts) + mScrollOffsetPrimary; 1871 int rowIndex = sTwoInts[0]; 1872 int pos = sTwoInts[1]; 1873 int savedMaxEdge = mWindowAlignment.mainAxis().getMaxEdge(); 1874 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1875 int maxScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1876 mWindowAlignment.mainAxis().setMaxEdge(savedMaxEdge); 1877 1878 if (highAvailable) { 1879 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1880 mWindowAlignment.mainAxis().setMaxScroll(maxScroll); 1881 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge + 1882 " scrollMax to " + maxScroll); 1883 } else { 1884 mWindowAlignment.mainAxis().invalidateScrollMax(); 1885 if (DEBUG) Log.v(getTag(), "Invalidate scrollMax since it should be " 1886 + "greater than " + maxScroll); 1887 } 1888 } 1889 1890 private void updateScrollMin() { 1891 int lowVisiblePos = (!mReverseFlowPrimary) ? mGrid.getFirstVisibleIndex() 1892 : mGrid.getLastVisibleIndex(); 1893 int lowMinPos = (!mReverseFlowPrimary) ? 0 : mState.getItemCount() - 1; 1894 if (lowVisiblePos < 0) { 1895 return; 1896 } 1897 final boolean lowAvailable = lowVisiblePos == lowMinPos; 1898 final boolean minUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1899 if (!lowAvailable && minUnknown) { 1900 return; 1901 } 1902 int minEdge = mGrid.findRowMin(false, sTwoInts) + mScrollOffsetPrimary; 1903 int rowIndex = sTwoInts[0]; 1904 int pos = sTwoInts[1]; 1905 int savedMinEdge = mWindowAlignment.mainAxis().getMinEdge(); 1906 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1907 int minScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1908 mWindowAlignment.mainAxis().setMinEdge(savedMinEdge); 1909 1910 if (lowAvailable) { 1911 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1912 mWindowAlignment.mainAxis().setMinScroll(minScroll); 1913 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge + 1914 " scrollMin to " + minScroll); 1915 } else { 1916 mWindowAlignment.mainAxis().invalidateScrollMin(); 1917 if (DEBUG) Log.v(getTag(), "Invalidate scrollMin, since it should be " 1918 + "less than " + minScroll); 1919 } 1920 } 1921 1922 private void updateScrollSecondAxis() { 1923 mWindowAlignment.secondAxis().setMinEdge(0); 1924 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1925 } 1926 1927 private void initScrollController() { 1928 mWindowAlignment.reset(); 1929 mWindowAlignment.horizontal.setSize(getWidth()); 1930 mWindowAlignment.vertical.setSize(getHeight()); 1931 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1932 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1933 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1934 mScrollOffsetPrimary = -mWindowAlignment.mainAxis().getPaddingLow(); 1935 mScrollOffsetSecondary = -mWindowAlignment.secondAxis().getPaddingLow(); 1936 1937 if (DEBUG) { 1938 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1939 + " mWindowAlignment " + mWindowAlignment 1940 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1941 } 1942 } 1943 1944 private void updateScrollController() { 1945 // mScrollOffsetPrimary and mScrollOffsetSecondary includes the padding. 1946 // e.g. when topPadding is 16 for horizontal grid view, the initial 1947 // mScrollOffsetSecondary is -16. fastRelayout() put views based on offsets(not padding), 1948 // when padding changes to 20, we also need update mScrollOffsetSecondary to -20 before 1949 // fastRelayout() is performed 1950 int paddingPrimaryDiff, paddingSecondaryDiff; 1951 if (mOrientation == HORIZONTAL) { 1952 paddingPrimaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1953 paddingSecondaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1954 } else { 1955 paddingPrimaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1956 paddingSecondaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1957 } 1958 mScrollOffsetPrimary -= paddingPrimaryDiff; 1959 mScrollOffsetSecondary -= paddingSecondaryDiff; 1960 1961 mWindowAlignment.horizontal.setSize(getWidth()); 1962 mWindowAlignment.vertical.setSize(getHeight()); 1963 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1964 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1965 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1966 1967 if (DEBUG) { 1968 Log.v(getTag(), "updateScrollController mSizePrimary " + mSizePrimary 1969 + " mWindowAlignment " + mWindowAlignment 1970 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1971 } 1972 } 1973 1974 public void setSelection(RecyclerView parent, int position, 1975 int primaryScrollExtra) { 1976 setSelection(parent, position, false, primaryScrollExtra); 1977 } 1978 1979 public void setSelectionSmooth(RecyclerView parent, int position) { 1980 setSelection(parent, position, true, 0); 1981 } 1982 1983 public int getSelection() { 1984 return mFocusPosition; 1985 } 1986 1987 public void setSelection(RecyclerView parent, int position, boolean smooth, 1988 int primaryScrollExtra) { 1989 if (mFocusPosition != position && position != NO_POSITION 1990 || primaryScrollExtra != mPrimaryScrollExtra) { 1991 scrollToSelection(parent, position, smooth, primaryScrollExtra); 1992 } 1993 } 1994 1995 private void scrollToSelection(RecyclerView parent, int position, boolean smooth, 1996 int primaryScrollExtra) { 1997 if (TRACE) TraceHelper.beginSection("scrollToSelection"); 1998 mPrimaryScrollExtra = primaryScrollExtra; 1999 View view = findViewByPosition(position); 2000 if (view != null) { 2001 mInSelection = true; 2002 scrollToView(view, smooth); 2003 mInSelection = false; 2004 } else { 2005 mFocusPosition = position; 2006 mFocusPositionOffset = 0; 2007 if (!mLayoutEnabled) { 2008 return; 2009 } 2010 if (smooth) { 2011 if (!hasDoneFirstLayout()) { 2012 Log.w(getTag(), "setSelectionSmooth should " + 2013 "not be called before first layout pass"); 2014 return; 2015 } 2016 startPositionSmoothScroller(position); 2017 } else { 2018 mForceFullLayout = true; 2019 parent.requestLayout(); 2020 } 2021 } 2022 if (TRACE) TraceHelper.endSection(); 2023 } 2024 2025 void startPositionSmoothScroller(int position) { 2026 LinearSmoothScroller linearSmoothScroller = new GridLinearSmoothScroller() { 2027 @Override 2028 public PointF computeScrollVectorForPosition(int targetPosition) { 2029 if (getChildCount() == 0) { 2030 return null; 2031 } 2032 final int firstChildPos = getPosition(getChildAt(0)); 2033 // TODO We should be able to deduce direction from bounds of current and target 2034 // focus, rather than making assumptions about positions and directionality 2035 final boolean isStart = mReverseFlowPrimary ? targetPosition > firstChildPos 2036 : targetPosition < firstChildPos; 2037 final int direction = isStart ? -1 : 1; 2038 if (mOrientation == HORIZONTAL) { 2039 return new PointF(direction, 0); 2040 } else { 2041 return new PointF(0, direction); 2042 } 2043 } 2044 2045 }; 2046 linearSmoothScroller.setTargetPosition(position); 2047 startSmoothScroll(linearSmoothScroller); 2048 } 2049 2050 private void processPendingMovement(boolean forward) { 2051 if (forward ? hasCreatedLastItem() : hasCreatedFirstItem()) { 2052 return; 2053 } 2054 if (mPendingMoveSmoothScroller == null) { 2055 // Stop existing scroller and create a new PendingMoveSmoothScroller. 2056 mBaseGridView.stopScroll(); 2057 PendingMoveSmoothScroller linearSmoothScroller = new PendingMoveSmoothScroller( 2058 forward ? 1 : -1, mNumRows > 1); 2059 mFocusPositionOffset = 0; 2060 startSmoothScroll(linearSmoothScroller); 2061 if (linearSmoothScroller.isRunning()) { 2062 mPendingMoveSmoothScroller = linearSmoothScroller; 2063 } 2064 } else { 2065 if (forward) { 2066 mPendingMoveSmoothScroller.increasePendingMoves(); 2067 } else { 2068 mPendingMoveSmoothScroller.decreasePendingMoves(); 2069 } 2070 } 2071 } 2072 2073 @Override 2074 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 2075 if (DEBUG) Log.v(getTag(), "onItemsAdded positionStart " 2076 + positionStart + " itemCount " + itemCount); 2077 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2078 int pos = mFocusPosition + mFocusPositionOffset; 2079 if (positionStart <= pos) { 2080 mFocusPositionOffset += itemCount; 2081 } 2082 } 2083 mChildrenStates.clear(); 2084 } 2085 2086 @Override 2087 public void onItemsChanged(RecyclerView recyclerView) { 2088 if (DEBUG) Log.v(getTag(), "onItemsChanged"); 2089 mFocusPositionOffset = 0; 2090 mChildrenStates.clear(); 2091 } 2092 2093 @Override 2094 public void onItemsRemoved(RecyclerView recyclerView, int positionStart, int itemCount) { 2095 if (DEBUG) Log.v(getTag(), "onItemsRemoved positionStart " 2096 + positionStart + " itemCount " + itemCount); 2097 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2098 int pos = mFocusPosition + mFocusPositionOffset; 2099 if (positionStart <= pos) { 2100 if (positionStart + itemCount > pos) { 2101 // stop updating offset after the focus item was removed 2102 mFocusPositionOffset = Integer.MIN_VALUE; 2103 } else { 2104 mFocusPositionOffset -= itemCount; 2105 } 2106 } 2107 } 2108 mChildrenStates.clear(); 2109 } 2110 2111 @Override 2112 public void onItemsMoved(RecyclerView recyclerView, int fromPosition, int toPosition, 2113 int itemCount) { 2114 if (DEBUG) Log.v(getTag(), "onItemsMoved fromPosition " 2115 + fromPosition + " toPosition " + toPosition); 2116 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2117 int pos = mFocusPosition + mFocusPositionOffset; 2118 if (fromPosition <= pos && pos < fromPosition + itemCount) { 2119 // moved items include focused position 2120 mFocusPositionOffset += toPosition - fromPosition; 2121 } else if (fromPosition < pos && toPosition > pos - itemCount) { 2122 // move items before focus position to after focused position 2123 mFocusPositionOffset -= itemCount; 2124 } else if (fromPosition > pos && toPosition < pos) { 2125 // move items after focus position to before focused position 2126 mFocusPositionOffset += itemCount; 2127 } 2128 } 2129 mChildrenStates.clear(); 2130 } 2131 2132 @Override 2133 public void onItemsUpdated(RecyclerView recyclerView, int positionStart, int itemCount) { 2134 if (DEBUG) Log.v(getTag(), "onItemsUpdated positionStart " 2135 + positionStart + " itemCount " + itemCount); 2136 for (int i = positionStart, end = positionStart + itemCount; i < end; i++) { 2137 mChildrenStates.remove(i); 2138 } 2139 } 2140 2141 @Override 2142 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 2143 if (mFocusSearchDisabled) { 2144 return true; 2145 } 2146 if (getPositionByView(child) == NO_POSITION) { 2147 // This shouldn't happen, but in case it does be sure not to attempt a 2148 // scroll to a view whose item has been removed. 2149 return true; 2150 } 2151 if (!mInLayout && !mInSelection && !mInScroll) { 2152 scrollToView(child, true); 2153 } 2154 return true; 2155 } 2156 2157 @Override 2158 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 2159 boolean immediate) { 2160 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 2161 return false; 2162 } 2163 2164 int getScrollOffsetX() { 2165 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 2166 } 2167 2168 int getScrollOffsetY() { 2169 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 2170 } 2171 2172 public void getViewSelectedOffsets(View view, int[] offsets) { 2173 if (mOrientation == HORIZONTAL) { 2174 offsets[0] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2175 offsets[1] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2176 } else { 2177 offsets[1] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2178 offsets[0] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2179 } 2180 } 2181 2182 private int getPrimarySystemScrollPosition(View view) { 2183 final int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 2184 final int viewMin = getViewMin(view); 2185 final int viewMax = getViewMax(view); 2186 // TODO: change to use State object in onRequestChildFocus() 2187 boolean isMin, isMax; 2188 if (!mReverseFlowPrimary) { 2189 isMin = mGrid.getFirstVisibleIndex() == 0; 2190 isMax = mGrid.getLastVisibleIndex() == (mState == null ? 2191 getItemCount() : mState.getItemCount()) - 1; 2192 } else { 2193 isMax = mGrid.getFirstVisibleIndex() == 0; 2194 isMin = mGrid.getLastVisibleIndex() == (mState == null ? 2195 getItemCount() : mState.getItemCount()) - 1; 2196 } 2197 for (int i = getChildCount() - 1; (isMin || isMax) && i >= 0; i--) { 2198 View v = getChildAt(i); 2199 if (v == view || v == null) { 2200 continue; 2201 } 2202 if (isMin && getViewMin(v) < viewMin) { 2203 isMin = false; 2204 } 2205 if (isMax && getViewMax(v) > viewMax) { 2206 isMax = false; 2207 } 2208 } 2209 return mWindowAlignment.mainAxis().getSystemScrollPos(viewCenterPrimary, isMin, isMax); 2210 } 2211 2212 private int getSecondarySystemScrollPosition(View view) { 2213 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 2214 int pos = getPositionByView(view); 2215 Grid.Location location = mGrid.getLocation(pos); 2216 final int row = location.row; 2217 final boolean isMin, isMax; 2218 if (!mReverseFlowSecondary) { 2219 isMin = row == 0; 2220 isMax = row == mGrid.getNumRows() - 1; 2221 } else { 2222 isMax = row == 0; 2223 isMin = row == mGrid.getNumRows() - 1; 2224 } 2225 return mWindowAlignment.secondAxis().getSystemScrollPos(viewCenterSecondary, isMin, isMax); 2226 } 2227 2228 /** 2229 * Scroll to a given child view and change mFocusPosition. 2230 */ 2231 private void scrollToView(View view, boolean smooth) { 2232 int newFocusPosition = getPositionByView(view); 2233 if (newFocusPosition != mFocusPosition) { 2234 mFocusPosition = newFocusPosition; 2235 mFocusPositionOffset = 0; 2236 if (!mInLayout) { 2237 dispatchChildSelected(); 2238 } 2239 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 2240 mBaseGridView.invalidate(); 2241 } 2242 } 2243 if (view == null) { 2244 return; 2245 } 2246 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 2247 // transfer focus to the child if it does not have focus yet (e.g. triggered 2248 // by setSelection()) 2249 view.requestFocus(); 2250 } 2251 if (!mScrollEnabled && smooth) { 2252 return; 2253 } 2254 if (getScrollPosition(view, sTwoInts)) { 2255 scrollGrid(sTwoInts[0], sTwoInts[1], smooth); 2256 } 2257 } 2258 2259 private boolean getScrollPosition(View view, int[] deltas) { 2260 switch (mFocusScrollStrategy) { 2261 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2262 default: 2263 return getAlignedPosition(view, deltas); 2264 case BaseGridView.FOCUS_SCROLL_ITEM: 2265 case BaseGridView.FOCUS_SCROLL_PAGE: 2266 return getNoneAlignedPosition(view, deltas); 2267 } 2268 } 2269 2270 private boolean getNoneAlignedPosition(View view, int[] deltas) { 2271 int pos = getPositionByView(view); 2272 int viewMin = getViewMin(view); 2273 int viewMax = getViewMax(view); 2274 // we either align "firstView" to left/top padding edge 2275 // or align "lastView" to right/bottom padding edge 2276 View firstView = null; 2277 View lastView = null; 2278 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 2279 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 2280 final int row = mGrid.getRowIndex(pos); 2281 if (viewMin < paddingLow) { 2282 // view enters low padding area: 2283 firstView = view; 2284 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2285 // scroll one "page" left/top, 2286 // align first visible item of the "page" at the low padding edge. 2287 while (prependOneColumnVisibleItems()) { 2288 CircularIntArray positions = 2289 mGrid.getItemPositionsInRows(mGrid.getFirstVisibleIndex(), pos)[row]; 2290 firstView = findViewByPosition(positions.get(0)); 2291 if (viewMax - getViewMin(firstView) > clientSize) { 2292 if (positions.size() > 2) { 2293 firstView = findViewByPosition(positions.get(2)); 2294 } 2295 break; 2296 } 2297 } 2298 } 2299 } else if (viewMax > clientSize + paddingLow) { 2300 // view enters high padding area: 2301 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2302 // scroll whole one page right/bottom, align view at the low padding edge. 2303 firstView = view; 2304 do { 2305 CircularIntArray positions = 2306 mGrid.getItemPositionsInRows(pos, mGrid.getLastVisibleIndex())[row]; 2307 lastView = findViewByPosition(positions.get(positions.size() - 1)); 2308 if (getViewMax(lastView) - viewMin > clientSize) { 2309 lastView = null; 2310 break; 2311 } 2312 } while (appendOneColumnVisibleItems()); 2313 if (lastView != null) { 2314 // however if we reached end, we should align last view. 2315 firstView = null; 2316 } 2317 } else { 2318 lastView = view; 2319 } 2320 } 2321 int scrollPrimary = 0; 2322 int scrollSecondary = 0; 2323 if (firstView != null) { 2324 scrollPrimary = getViewMin(firstView) - paddingLow; 2325 } else if (lastView != null) { 2326 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 2327 } 2328 View secondaryAlignedView; 2329 if (firstView != null) { 2330 secondaryAlignedView = firstView; 2331 } else if (lastView != null) { 2332 secondaryAlignedView = lastView; 2333 } else { 2334 secondaryAlignedView = view; 2335 } 2336 scrollSecondary = getSecondarySystemScrollPosition(secondaryAlignedView); 2337 scrollSecondary -= mScrollOffsetSecondary; 2338 if (scrollPrimary != 0 || scrollSecondary != 0) { 2339 deltas[0] = scrollPrimary; 2340 deltas[1] = scrollSecondary; 2341 return true; 2342 } 2343 return false; 2344 } 2345 2346 private boolean getAlignedPosition(View view, int[] deltas) { 2347 int scrollPrimary = getPrimarySystemScrollPosition(view); 2348 int scrollSecondary = getSecondarySystemScrollPosition(view); 2349 if (DEBUG) { 2350 Log.v(getTag(), "getAlignedPosition " + scrollPrimary + " " + scrollSecondary 2351 + " " + mPrimaryScrollExtra + " " + mWindowAlignment); 2352 Log.v(getTag(), "getAlignedPosition " + mScrollOffsetPrimary + " " + mScrollOffsetSecondary); 2353 } 2354 scrollPrimary -= mScrollOffsetPrimary; 2355 scrollSecondary -= mScrollOffsetSecondary; 2356 scrollPrimary += mPrimaryScrollExtra; 2357 if (scrollPrimary != 0 || scrollSecondary != 0) { 2358 deltas[0] = scrollPrimary; 2359 deltas[1] = scrollSecondary; 2360 return true; 2361 } 2362 return false; 2363 } 2364 2365 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 2366 if (mInLayout) { 2367 scrollDirectionPrimary(scrollPrimary); 2368 scrollDirectionSecondary(scrollSecondary); 2369 } else { 2370 int scrollX; 2371 int scrollY; 2372 if (mOrientation == HORIZONTAL) { 2373 scrollX = scrollPrimary; 2374 scrollY = scrollSecondary; 2375 } else { 2376 scrollX = scrollSecondary; 2377 scrollY = scrollPrimary; 2378 } 2379 if (smooth) { 2380 mBaseGridView.smoothScrollBy(scrollX, scrollY); 2381 } else { 2382 mBaseGridView.scrollBy(scrollX, scrollY); 2383 } 2384 } 2385 } 2386 2387 public void setPruneChild(boolean pruneChild) { 2388 if (mPruneChild != pruneChild) { 2389 mPruneChild = pruneChild; 2390 if (mPruneChild) { 2391 requestLayout(); 2392 } 2393 } 2394 } 2395 2396 public boolean getPruneChild() { 2397 return mPruneChild; 2398 } 2399 2400 public void setScrollEnabled(boolean scrollEnabled) { 2401 if (mScrollEnabled != scrollEnabled) { 2402 mScrollEnabled = scrollEnabled; 2403 if (mScrollEnabled && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED 2404 && mFocusPosition != NO_POSITION) { 2405 scrollToSelection(mBaseGridView, mFocusPosition, true, mPrimaryScrollExtra); 2406 } 2407 } 2408 } 2409 2410 public boolean isScrollEnabled() { 2411 return mScrollEnabled; 2412 } 2413 2414 private int findImmediateChildIndex(View view) { 2415 while (view != null && view != mBaseGridView) { 2416 int index = mBaseGridView.indexOfChild(view); 2417 if (index >= 0) { 2418 return index; 2419 } 2420 view = (View) view.getParent(); 2421 } 2422 return NO_POSITION; 2423 } 2424 2425 void setFocusSearchDisabled(boolean disabled) { 2426 mFocusSearchDisabled = disabled; 2427 } 2428 2429 boolean isFocusSearchDisabled() { 2430 return mFocusSearchDisabled; 2431 } 2432 2433 @Override 2434 public View onInterceptFocusSearch(View focused, int direction) { 2435 if (mFocusSearchDisabled) { 2436 return focused; 2437 } 2438 return null; 2439 } 2440 2441 boolean hasPreviousViewInSameRow(int pos) { 2442 if (mGrid == null || pos == NO_POSITION || mGrid.getFirstVisibleIndex() < 0) { 2443 return false; 2444 } 2445 if (mGrid.getFirstVisibleIndex() > 0) { 2446 return true; 2447 } 2448 final int focusedRow = mGrid.getLocation(pos).row; 2449 for (int i = getChildCount() - 1; i >= 0; i--) { 2450 int position = getPositionByIndex(i); 2451 Grid.Location loc = mGrid.getLocation(position); 2452 if (loc != null && loc.row == focusedRow) { 2453 if (position < pos) { 2454 return true; 2455 } 2456 } 2457 } 2458 return false; 2459 } 2460 2461 @Override 2462 public boolean onAddFocusables(RecyclerView recyclerView, 2463 ArrayList<View> views, int direction, int focusableMode) { 2464 if (mFocusSearchDisabled) { 2465 return true; 2466 } 2467 // If this viewgroup or one of its children currently has focus then we 2468 // consider our children for focus searching in main direction on the same row. 2469 // If this viewgroup has no focus and using focus align, we want the system 2470 // to ignore our children and pass focus to the viewgroup, which will pass 2471 // focus on to its children appropriately. 2472 // If this viewgroup has no focus and not using focus align, we want to 2473 // consider the child that does not overlap with padding area. 2474 if (recyclerView.hasFocus()) { 2475 final int movement = getMovement(direction); 2476 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2477 // Move on secondary direction uses default addFocusables(). 2478 return false; 2479 } 2480 if (mPendingMoveSmoothScroller != null) { 2481 // don't find next focusable if has pending movement. 2482 return true; 2483 } 2484 final View focused = recyclerView.findFocus(); 2485 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2486 // Add focusables of focused item. 2487 if (focusedPos != NO_POSITION) { 2488 findViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2489 } 2490 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2491 mGrid.getLocation(focusedPos).row : NO_POSITION; 2492 // Add focusables of next neighbor of same row on the focus search direction. 2493 if (mGrid != null) { 2494 final int focusableCount = views.size(); 2495 for (int i = 0, count = getChildCount(); i < count; i++) { 2496 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2497 final View child = getChildAt(index); 2498 if (child.getVisibility() != View.VISIBLE || !child.hasFocusable()) { 2499 continue; 2500 } 2501 int position = getPositionByIndex(index); 2502 Grid.Location loc = mGrid.getLocation(position); 2503 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2504 if (focusedPos == NO_POSITION || 2505 (movement == NEXT_ITEM && position > focusedPos) 2506 || (movement == PREV_ITEM && position < focusedPos)) { 2507 child.addFocusables(views, direction, focusableMode); 2508 if (views.size() > focusableCount) { 2509 break; 2510 } 2511 } 2512 } 2513 } 2514 } 2515 } else { 2516 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2517 // adding views not overlapping padding area to avoid scrolling in gaining focus 2518 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2519 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2520 int focusableCount = views.size(); 2521 for (int i = 0, count = getChildCount(); i < count; i++) { 2522 View child = getChildAt(i); 2523 if (child.getVisibility() == View.VISIBLE) { 2524 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2525 child.addFocusables(views, direction, focusableMode); 2526 } 2527 } 2528 } 2529 // if we cannot find any, then just add all children. 2530 if (views.size() == focusableCount) { 2531 for (int i = 0, count = getChildCount(); i < count; i++) { 2532 View child = getChildAt(i); 2533 if (child.getVisibility() == View.VISIBLE) { 2534 child.addFocusables(views, direction, focusableMode); 2535 } 2536 } 2537 if (views.size() != focusableCount) { 2538 return true; 2539 } 2540 } else { 2541 return true; 2542 } 2543 // if still cannot find any, fall through and add itself 2544 } 2545 if (recyclerView.isFocusable()) { 2546 views.add(recyclerView); 2547 } 2548 } 2549 return true; 2550 } 2551 2552 private boolean hasCreatedLastItem() { 2553 int count = mState.getItemCount(); 2554 return count == 0 || findViewByPosition(count - 1) != null; 2555 } 2556 2557 private boolean hasCreatedFirstItem() { 2558 int count = mState.getItemCount(); 2559 return count == 0 || findViewByPosition(0) != null; 2560 } 2561 2562 boolean canScrollTo(View view) { 2563 return view.getVisibility() == View.VISIBLE && (!hasFocus() || view.hasFocusable()); 2564 } 2565 2566 @Override 2567 public View onFocusSearchFailed(View focused, int direction, Recycler recycler, 2568 RecyclerView.State state) { 2569 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2570 2571 View view = null; 2572 int movement = getMovement(direction); 2573 final boolean isScroll = mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE; 2574 saveContext(recycler, state); 2575 if (movement == NEXT_ITEM) { 2576 if (isScroll || !mFocusOutEnd) { 2577 view = focused; 2578 } 2579 if (mScrollEnabled && !hasCreatedLastItem()) { 2580 processPendingMovement(true); 2581 view = focused; 2582 } 2583 } else if (movement == PREV_ITEM) { 2584 if (isScroll || !mFocusOutFront) { 2585 view = focused; 2586 } 2587 if (mScrollEnabled && !hasCreatedFirstItem()) { 2588 processPendingMovement(false); 2589 view = focused; 2590 } 2591 } 2592 leaveContext(); 2593 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed returning view " + view); 2594 return view; 2595 } 2596 2597 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2598 Rect previouslyFocusedRect) { 2599 switch (mFocusScrollStrategy) { 2600 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2601 default: 2602 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2603 direction, previouslyFocusedRect); 2604 case BaseGridView.FOCUS_SCROLL_PAGE: 2605 case BaseGridView.FOCUS_SCROLL_ITEM: 2606 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2607 direction, previouslyFocusedRect); 2608 } 2609 } 2610 2611 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2612 int direction, Rect previouslyFocusedRect) { 2613 View view = findViewByPosition(mFocusPosition); 2614 if (view != null) { 2615 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2616 if (!result && DEBUG) { 2617 Log.w(getTag(), "failed to request focus on " + view); 2618 } 2619 return result; 2620 } 2621 return false; 2622 } 2623 2624 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2625 int direction, Rect previouslyFocusedRect) { 2626 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2627 int index; 2628 int increment; 2629 int end; 2630 int count = getChildCount(); 2631 if ((direction & View.FOCUS_FORWARD) != 0) { 2632 index = 0; 2633 increment = 1; 2634 end = count; 2635 } else { 2636 index = count - 1; 2637 increment = -1; 2638 end = -1; 2639 } 2640 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2641 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2642 for (int i = index; i != end; i += increment) { 2643 View child = getChildAt(i); 2644 if (child.getVisibility() == View.VISIBLE) { 2645 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2646 if (child.requestFocus(direction, previouslyFocusedRect)) { 2647 return true; 2648 } 2649 } 2650 } 2651 } 2652 return false; 2653 } 2654 2655 private final static int PREV_ITEM = 0; 2656 private final static int NEXT_ITEM = 1; 2657 private final static int PREV_ROW = 2; 2658 private final static int NEXT_ROW = 3; 2659 2660 private int getMovement(int direction) { 2661 int movement = View.FOCUS_LEFT; 2662 2663 if (mOrientation == HORIZONTAL) { 2664 switch(direction) { 2665 case View.FOCUS_LEFT: 2666 movement = (!mReverseFlowPrimary) ? PREV_ITEM : NEXT_ITEM; 2667 break; 2668 case View.FOCUS_RIGHT: 2669 movement = (!mReverseFlowPrimary) ? NEXT_ITEM : PREV_ITEM; 2670 break; 2671 case View.FOCUS_UP: 2672 movement = PREV_ROW; 2673 break; 2674 case View.FOCUS_DOWN: 2675 movement = NEXT_ROW; 2676 break; 2677 } 2678 } else if (mOrientation == VERTICAL) { 2679 switch(direction) { 2680 case View.FOCUS_LEFT: 2681 movement = (!mReverseFlowPrimary) ? PREV_ROW : NEXT_ROW; 2682 break; 2683 case View.FOCUS_RIGHT: 2684 movement = (!mReverseFlowPrimary) ? NEXT_ROW : PREV_ROW; 2685 break; 2686 case View.FOCUS_UP: 2687 movement = PREV_ITEM; 2688 break; 2689 case View.FOCUS_DOWN: 2690 movement = NEXT_ITEM; 2691 break; 2692 } 2693 } 2694 2695 return movement; 2696 } 2697 2698 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2699 View view = findViewByPosition(mFocusPosition); 2700 if (view == null) { 2701 return i; 2702 } 2703 int focusIndex = recyclerView.indexOfChild(view); 2704 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2705 // drawing order is 0 1 2 3 9 8 7 6 5 4 2706 if (i < focusIndex) { 2707 return i; 2708 } else if (i < childCount - 1) { 2709 return focusIndex + childCount - 1 - i; 2710 } else { 2711 return focusIndex; 2712 } 2713 } 2714 2715 @Override 2716 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2717 RecyclerView.Adapter newAdapter) { 2718 if (DEBUG) Log.v(getTag(), "onAdapterChanged to " + newAdapter); 2719 if (oldAdapter != null) { 2720 discardLayoutInfo(); 2721 mFocusPosition = NO_POSITION; 2722 mFocusPositionOffset = 0; 2723 mChildrenStates.clear(); 2724 } 2725 super.onAdapterChanged(oldAdapter, newAdapter); 2726 } 2727 2728 private void discardLayoutInfo() { 2729 mGrid = null; 2730 mRowSizeSecondary = null; 2731 mRowSecondarySizeRefresh = false; 2732 } 2733 2734 public void setLayoutEnabled(boolean layoutEnabled) { 2735 if (mLayoutEnabled != layoutEnabled) { 2736 mLayoutEnabled = layoutEnabled; 2737 requestLayout(); 2738 } 2739 } 2740 2741 void setChildrenVisibility(int visiblity) { 2742 mChildVisibility = visiblity; 2743 if (mChildVisibility != -1) { 2744 int count = getChildCount(); 2745 for (int i= 0; i < count; i++) { 2746 getChildAt(i).setVisibility(mChildVisibility); 2747 } 2748 } 2749 } 2750 2751 final static class SavedState implements Parcelable { 2752 2753 int index; // index inside adapter of the current view 2754 Bundle childStates = Bundle.EMPTY; 2755 2756 @Override 2757 public void writeToParcel(Parcel out, int flags) { 2758 out.writeInt(index); 2759 out.writeBundle(childStates); 2760 } 2761 2762 @SuppressWarnings("hiding") 2763 public static final Parcelable.Creator<SavedState> CREATOR = 2764 new Parcelable.Creator<SavedState>() { 2765 @Override 2766 public SavedState createFromParcel(Parcel in) { 2767 return new SavedState(in); 2768 } 2769 2770 @Override 2771 public SavedState[] newArray(int size) { 2772 return new SavedState[size]; 2773 } 2774 }; 2775 2776 @Override 2777 public int describeContents() { 2778 return 0; 2779 } 2780 2781 SavedState(Parcel in) { 2782 index = in.readInt(); 2783 childStates = in.readBundle(GridLayoutManager.class.getClassLoader()); 2784 } 2785 2786 SavedState() { 2787 } 2788 } 2789 2790 @Override 2791 public Parcelable onSaveInstanceState() { 2792 if (DEBUG) Log.v(getTag(), "onSaveInstanceState getSelection() " + getSelection()); 2793 SavedState ss = new SavedState(); 2794 for (int i = 0, count = getChildCount(); i < count; i++) { 2795 View view = getChildAt(i); 2796 int position = getPositionByView(view); 2797 if (position != NO_POSITION) { 2798 mChildrenStates.saveOnScreenView(view, position); 2799 } 2800 } 2801 ss.index = getSelection(); 2802 ss.childStates = mChildrenStates.saveAsBundle(); 2803 return ss; 2804 } 2805 2806 void onChildRecycled(RecyclerView.ViewHolder holder) { 2807 final int position = holder.getAdapterPosition(); 2808 if (position != NO_POSITION) { 2809 mChildrenStates.saveOffscreenView(holder.itemView, position); 2810 } 2811 } 2812 2813 @Override 2814 public void onRestoreInstanceState(Parcelable state) { 2815 if (!(state instanceof SavedState)) { 2816 return; 2817 } 2818 SavedState loadingState = (SavedState)state; 2819 mFocusPosition = loadingState.index; 2820 mFocusPositionOffset = 0; 2821 mChildrenStates.loadFromBundle(loadingState.childStates); 2822 mForceFullLayout = true; 2823 requestLayout(); 2824 if (DEBUG) Log.v(getTag(), "onRestoreInstanceState mFocusPosition " + mFocusPosition); 2825 } 2826} 2827