GridLayoutManager.java revision 5c13a7806aa6c44e9711beb98797d06f3b2f0259
1/* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except 5 * in compliance with the License. You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software distributed under the License 10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express 11 * or implied. See the License for the specific language governing permissions and limitations under 12 * the License. 13 */ 14package android.support.v17.leanback.widget; 15 16import android.content.Context; 17import android.graphics.PointF; 18import android.graphics.Rect; 19import android.os.Bundle; 20import android.os.Parcel; 21import android.os.Parcelable; 22import android.support.v4.util.CircularIntArray; 23import android.support.v4.view.ViewCompat; 24import android.support.v7.widget.LinearSmoothScroller; 25import android.support.v7.widget.RecyclerView; 26import android.support.v7.widget.RecyclerView.Recycler; 27import android.support.v7.widget.RecyclerView.State; 28import android.support.v17.leanback.os.TraceHelper; 29 30import static android.support.v7.widget.RecyclerView.NO_ID; 31import static android.support.v7.widget.RecyclerView.NO_POSITION; 32import static android.support.v7.widget.RecyclerView.HORIZONTAL; 33import static android.support.v7.widget.RecyclerView.VERTICAL; 34 35import android.util.AttributeSet; 36import android.util.Log; 37import android.view.FocusFinder; 38import android.view.Gravity; 39import android.view.View; 40import android.view.ViewParent; 41import android.view.View.MeasureSpec; 42import android.view.ViewGroup.MarginLayoutParams; 43import android.view.ViewGroup; 44 45import java.io.PrintWriter; 46import java.io.StringWriter; 47import java.util.ArrayList; 48import java.util.List; 49 50final class GridLayoutManager extends RecyclerView.LayoutManager { 51 52 /* 53 * LayoutParams for {@link HorizontalGridView} and {@link VerticalGridView}. 54 * The class currently does two internal jobs: 55 * - Saves optical bounds insets. 56 * - Caches focus align view center. 57 */ 58 static class LayoutParams extends RecyclerView.LayoutParams { 59 60 // The view is saved only during animation. 61 private View mView; 62 63 // For placement 64 private int mLeftInset; 65 private int mTopInset; 66 private int mRightInset; 67 private int mBottomInset; 68 69 // For alignment 70 private int mAlignX; 71 private int mAlignY; 72 73 public LayoutParams(Context c, AttributeSet attrs) { 74 super(c, attrs); 75 } 76 77 public LayoutParams(int width, int height) { 78 super(width, height); 79 } 80 81 public LayoutParams(MarginLayoutParams source) { 82 super(source); 83 } 84 85 public LayoutParams(ViewGroup.LayoutParams source) { 86 super(source); 87 } 88 89 public LayoutParams(RecyclerView.LayoutParams source) { 90 super(source); 91 } 92 93 public LayoutParams(LayoutParams source) { 94 super(source); 95 } 96 97 int getAlignX() { 98 return mAlignX; 99 } 100 101 int getAlignY() { 102 return mAlignY; 103 } 104 105 int getOpticalLeft(View view) { 106 return view.getLeft() + mLeftInset; 107 } 108 109 int getOpticalTop(View view) { 110 return view.getTop() + mTopInset; 111 } 112 113 int getOpticalRight(View view) { 114 return view.getRight() - mRightInset; 115 } 116 117 int getOpticalBottom(View view) { 118 return view.getBottom() - mBottomInset; 119 } 120 121 int getOpticalWidth(View view) { 122 return view.getWidth() - mLeftInset - mRightInset; 123 } 124 125 int getOpticalHeight(View view) { 126 return view.getHeight() - mTopInset - mBottomInset; 127 } 128 129 int getOpticalLeftInset() { 130 return mLeftInset; 131 } 132 133 int getOpticalRightInset() { 134 return mRightInset; 135 } 136 137 int getOpticalTopInset() { 138 return mTopInset; 139 } 140 141 int getOpticalBottomInset() { 142 return mBottomInset; 143 } 144 145 void setAlignX(int alignX) { 146 mAlignX = alignX; 147 } 148 149 void setAlignY(int alignY) { 150 mAlignY = alignY; 151 } 152 153 void setOpticalInsets(int leftInset, int topInset, int rightInset, int bottomInset) { 154 mLeftInset = leftInset; 155 mTopInset = topInset; 156 mRightInset = rightInset; 157 mBottomInset = bottomInset; 158 } 159 160 private void invalidateItemDecoration() { 161 ViewParent parent = mView.getParent(); 162 if (parent instanceof RecyclerView) { 163 // TODO: we only need invalidate parent if it has ItemDecoration 164 ((RecyclerView) parent).invalidate(); 165 } 166 } 167 } 168 169 /** 170 * Base class which scrolls to selected view in onStop(). 171 */ 172 abstract class GridLinearSmoothScroller extends LinearSmoothScroller { 173 GridLinearSmoothScroller() { 174 super(mBaseGridView.getContext()); 175 } 176 177 @Override 178 protected void onStop() { 179 // onTargetFound() may not be called if we hit the "wall" first. 180 View targetView = findViewByPosition(getTargetPosition()); 181 if (hasFocus() && targetView != null) { 182 mInSelection = true; 183 targetView.requestFocus(); 184 mInSelection = false; 185 } 186 if (needsDispatchChildSelectedOnStop()) { 187 dispatchChildSelected(); 188 } 189 super.onStop(); 190 } 191 192 boolean needsDispatchChildSelectedOnStop() { 193 return true; 194 } 195 196 @Override 197 protected void onTargetFound(View targetView, 198 RecyclerView.State state, Action action) { 199 if (getScrollPosition(targetView, sTwoInts)) { 200 int dx, dy; 201 if (mOrientation == HORIZONTAL) { 202 dx = sTwoInts[0]; 203 dy = sTwoInts[1]; 204 } else { 205 dx = sTwoInts[1]; 206 dy = sTwoInts[0]; 207 } 208 final int distance = (int) Math.sqrt(dx * dx + dy * dy); 209 final int time = calculateTimeForDeceleration(distance); 210 action.update(dx, dy, time, mDecelerateInterpolator); 211 } 212 } 213 } 214 215 /** 216 * The SmoothScroller that remembers pending DPAD keys and consume pending keys 217 * during scroll. 218 */ 219 final class PendingMoveSmoothScroller extends GridLinearSmoothScroller { 220 // -2 is a target position that LinearSmoothScroller can never find until 221 // consumePendingMovesXXX() sets real targetPosition. 222 final static int TARGET_UNDEFINED = -2; 223 // whether the grid is staggered. 224 private final boolean mStaggeredGrid; 225 // Number of pending movements on primary direction, negative if PREV_ITEM. 226 private int mPendingMoves; 227 228 PendingMoveSmoothScroller(int initialPendingMoves, boolean staggeredGrid) { 229 mPendingMoves = initialPendingMoves; 230 mStaggeredGrid = staggeredGrid; 231 setTargetPosition(TARGET_UNDEFINED); 232 } 233 234 void increasePendingMoves() { 235 if (mPendingMoves < MAX_PENDING_MOVES) { 236 mPendingMoves++; 237 if (mPendingMoves == 0) { 238 dispatchChildSelected(); 239 } 240 } 241 } 242 243 void decreasePendingMoves() { 244 if (mPendingMoves > -MAX_PENDING_MOVES) { 245 mPendingMoves--; 246 if (mPendingMoves == 0) { 247 dispatchChildSelected(); 248 } 249 } 250 } 251 252 /** 253 * Called before laid out an item when non-staggered grid can handle pending movements 254 * by skipping "mNumRows" per movement; staggered grid will have to wait the item 255 * has been laid out in consumePendingMovesAfterLayout(). 256 */ 257 void consumePendingMovesBeforeLayout() { 258 if (mStaggeredGrid || mPendingMoves == 0) { 259 return; 260 } 261 View newSelected = null; 262 int startPos = mPendingMoves > 0 ? mFocusPosition + mNumRows : 263 mFocusPosition - mNumRows; 264 for (int pos = startPos; mPendingMoves != 0; 265 pos = mPendingMoves > 0 ? pos + mNumRows: pos - mNumRows) { 266 View v = findViewByPosition(pos); 267 if (v == null) { 268 break; 269 } 270 if (!canScrollTo(v)) { 271 continue; 272 } 273 newSelected = v; 274 mFocusPosition = pos; 275 if (mPendingMoves > 0) { 276 mPendingMoves--; 277 } else { 278 mPendingMoves++; 279 } 280 } 281 if (newSelected != null && hasFocus()) { 282 mInSelection = true; 283 newSelected.requestFocus(); 284 mInSelection = false; 285 } 286 } 287 288 /** 289 * Called after laid out an item. Staggered grid should find view on same 290 * Row and consume pending movements. 291 */ 292 void consumePendingMovesAfterLayout() { 293 if (mStaggeredGrid && mPendingMoves != 0) { 294 // consume pending moves, focus to item on the same row. 295 final int focusedRow = mGrid != null && mFocusPosition != NO_POSITION ? 296 mGrid.getLocation(mFocusPosition).row : NO_POSITION; 297 View newSelected = null; 298 for (int i = 0, count = getChildCount(); i < count && mPendingMoves != 0; i++) { 299 int index = mPendingMoves > 0 ? i : count - 1 - i; 300 final View child = getChildAt(index); 301 if (!canScrollTo(child)) { 302 continue; 303 } 304 int position = getPositionByIndex(index); 305 Grid.Location loc = mGrid.getLocation(position); 306 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 307 if (mFocusPosition == NO_POSITION) { 308 mFocusPosition = position; 309 newSelected = child; 310 } else if ((mPendingMoves > 0 && position > mFocusPosition) 311 || (mPendingMoves < 0 && position < mFocusPosition)) { 312 mFocusPosition = position; 313 if (mPendingMoves > 0) { 314 mPendingMoves--; 315 } else { 316 mPendingMoves++; 317 } 318 newSelected = child; 319 } 320 } 321 } 322 if (newSelected != null && hasFocus()) { 323 mInSelection = true; 324 newSelected.requestFocus(); 325 mInSelection = false; 326 } 327 } 328 if (mPendingMoves == 0 || (mPendingMoves > 0 && hasCreatedLastItem()) 329 || (mPendingMoves < 0 && hasCreatedFirstItem())) { 330 setTargetPosition(mFocusPosition); 331 stop(); 332 } 333 } 334 335 @Override 336 protected void updateActionForInterimTarget(Action action) { 337 if (mPendingMoves == 0) { 338 return; 339 } 340 super.updateActionForInterimTarget(action); 341 } 342 343 @Override 344 public PointF computeScrollVectorForPosition(int targetPosition) { 345 if (mPendingMoves == 0) { 346 return null; 347 } 348 int direction = (mReverseFlowPrimary ? mPendingMoves > 0 : mPendingMoves < 0) ? 349 -1 : 1; 350 if (mOrientation == HORIZONTAL) { 351 return new PointF(direction, 0); 352 } else { 353 return new PointF(0, direction); 354 } 355 } 356 357 @Override 358 boolean needsDispatchChildSelectedOnStop() { 359 return mPendingMoves != 0; 360 } 361 362 @Override 363 protected void onStop() { 364 super.onStop(); 365 // if we hit wall, need clear the remaining pending moves. 366 mPendingMoves = 0; 367 mPendingMoveSmoothScroller = null; 368 View v = findViewByPosition(getTargetPosition()); 369 if (v != null) scrollToView(v, true); 370 } 371 }; 372 373 private static final String TAG = "GridLayoutManager"; 374 private static final boolean DEBUG = false; 375 private static final boolean TRACE = false; 376 377 // maximum pending movement in one direction. 378 private final static int MAX_PENDING_MOVES = 10; 379 380 private String getTag() { 381 return TAG + ":" + mBaseGridView.getId(); 382 } 383 384 private final BaseGridView mBaseGridView; 385 386 /** 387 * Note on conventions in the presence of RTL layout directions: 388 * Many properties and method names reference entities related to the 389 * beginnings and ends of things. In the presence of RTL flows, 390 * it may not be clear whether this is intended to reference a 391 * quantity that changes direction in RTL cases, or a quantity that 392 * does not. Here are the conventions in use: 393 * 394 * start/end: coordinate quantities - do reverse 395 * (optical) left/right: coordinate quantities - do not reverse 396 * low/high: coordinate quantities - do not reverse 397 * min/max: coordinate quantities - do not reverse 398 * scroll offset - coordinate quantities - do not reverse 399 * first/last: positional indices - do not reverse 400 * front/end: positional indices - do not reverse 401 * prepend/append: related to positional indices - do not reverse 402 * 403 * Note that although quantities do not reverse in RTL flows, their 404 * relationship does. In LTR flows, the first positional index is 405 * leftmost; in RTL flows, it is rightmost. Thus, anywhere that 406 * positional quantities are mapped onto coordinate quantities, 407 * the flow must be checked and the logic reversed. 408 */ 409 410 /** 411 * The orientation of a "row". 412 */ 413 private int mOrientation = HORIZONTAL; 414 415 private RecyclerView.State mState; 416 private RecyclerView.Recycler mRecycler; 417 418 private boolean mInLayout = false; 419 private boolean mInFastRelayout; 420 /** 421 * During full layout pass, when GridView had focus: onLayoutChildren will 422 * skip non-focusable child and adjust mFocusPosition. 423 */ 424 private boolean mInLayoutSearchFocus; 425 private boolean mInSelection = false; 426 427 private OnChildSelectedListener mChildSelectedListener = null; 428 429 private OnChildLaidOutListener mChildLaidOutListener = null; 430 431 /** 432 * The focused position, it's not the currently visually aligned position 433 * but it is the final position that we intend to focus on. If there are 434 * multiple setSelection() called, mFocusPosition saves last value. 435 */ 436 private int mFocusPosition = NO_POSITION; 437 438 /** 439 * LinearSmoothScroller that consume pending DPAD movements. 440 */ 441 private PendingMoveSmoothScroller mPendingMoveSmoothScroller; 442 443 /** 444 * The offset to be applied to mFocusPosition, due to adapter change, on the next 445 * layout. Set to Integer.MIN_VALUE means item was removed. 446 * TODO: This is somewhat duplication of RecyclerView getOldPosition() which is 447 * unfortunately cleared after prelayout. 448 */ 449 private int mFocusPositionOffset = 0; 450 451 /** 452 * Force a full layout under certain situations. E.g. Rows change, jump to invisible child. 453 */ 454 private boolean mForceFullLayout; 455 456 /** 457 * True if layout is enabled. 458 */ 459 private boolean mLayoutEnabled = true; 460 461 /** 462 * override child visibility 463 */ 464 private int mChildVisibility = -1; 465 466 /** 467 * The scroll offsets of the viewport relative to the entire view. 468 */ 469 private int mScrollOffsetPrimary; 470 private int mScrollOffsetSecondary; 471 472 /** 473 * User-specified row height/column width. Can be WRAP_CONTENT. 474 */ 475 private int mRowSizeSecondaryRequested; 476 477 /** 478 * The fixed size of each grid item in the secondary direction. This corresponds to 479 * the row height, equal for all rows. Grid items may have variable length 480 * in the primary direction. 481 */ 482 private int mFixedRowSizeSecondary; 483 484 /** 485 * Tracks the secondary size of each row. 486 */ 487 private int[] mRowSizeSecondary; 488 489 /** 490 * Flag controlling whether the current/next layout should 491 * be updating the secondary size of rows. 492 */ 493 private boolean mRowSecondarySizeRefresh; 494 495 /** 496 * The maximum measured size of the view. 497 */ 498 private int mMaxSizeSecondary; 499 500 /** 501 * Margin between items. 502 */ 503 private int mHorizontalMargin; 504 /** 505 * Margin between items vertically. 506 */ 507 private int mVerticalMargin; 508 /** 509 * Margin in main direction. 510 */ 511 private int mMarginPrimary; 512 /** 513 * Margin in second direction. 514 */ 515 private int mMarginSecondary; 516 /** 517 * How to position child in secondary direction. 518 */ 519 private int mGravity = Gravity.START | Gravity.TOP; 520 /** 521 * The number of rows in the grid. 522 */ 523 private int mNumRows; 524 /** 525 * Number of rows requested, can be 0 to be determined by parent size and 526 * rowHeight. 527 */ 528 private int mNumRowsRequested = 1; 529 530 /** 531 * Saves grid information of each view. 532 */ 533 Grid mGrid; 534 535 /** 536 * Focus Scroll strategy. 537 */ 538 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 539 /** 540 * Defines how item view is aligned in the window. 541 */ 542 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 543 544 /** 545 * Defines how item view is aligned. 546 */ 547 private final ItemAlignment mItemAlignment = new ItemAlignment(); 548 549 /** 550 * Dimensions of the view, width or height depending on orientation. 551 */ 552 private int mSizePrimary; 553 554 /** 555 * Allow DPAD key to navigate out at the front of the View (where position = 0), 556 * default is false. 557 */ 558 private boolean mFocusOutFront; 559 560 /** 561 * Allow DPAD key to navigate out at the end of the view, default is false. 562 */ 563 private boolean mFocusOutEnd; 564 565 /** 566 * True if focus search is disabled. 567 */ 568 private boolean mFocusSearchDisabled; 569 570 /** 571 * True if prune child, might be disabled during transition. 572 */ 573 private boolean mPruneChild = true; 574 575 /** 576 * True if scroll content, might be disabled during transition. 577 */ 578 private boolean mScrollEnabled = true; 579 580 /** 581 * Temporary variable: an int array of length=2. 582 */ 583 private static int[] sTwoInts = new int[2]; 584 585 /** 586 * Set to true for RTL layout in horizontal orientation 587 */ 588 private boolean mReverseFlowPrimary = false; 589 590 /** 591 * Set to true for RTL layout in vertical orientation 592 */ 593 private boolean mReverseFlowSecondary = false; 594 595 /** 596 * Temporaries used for measuring. 597 */ 598 private int[] mMeasuredDimension = new int[2]; 599 600 final ViewsStateBundle mChildrenStates = new ViewsStateBundle(); 601 602 public GridLayoutManager(BaseGridView baseGridView) { 603 mBaseGridView = baseGridView; 604 } 605 606 public void setOrientation(int orientation) { 607 if (orientation != HORIZONTAL && orientation != VERTICAL) { 608 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 609 return; 610 } 611 612 mOrientation = orientation; 613 mWindowAlignment.setOrientation(orientation); 614 mItemAlignment.setOrientation(orientation); 615 mForceFullLayout = true; 616 } 617 618 public void onRtlPropertiesChanged(int layoutDirection) { 619 if (mOrientation == HORIZONTAL) { 620 mReverseFlowPrimary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 621 mReverseFlowSecondary = false; 622 } else { 623 mReverseFlowSecondary = layoutDirection == View.LAYOUT_DIRECTION_RTL; 624 mReverseFlowPrimary = false; 625 } 626 mWindowAlignment.horizontal.setReversedFlow(layoutDirection == View.LAYOUT_DIRECTION_RTL); 627 } 628 629 public int getFocusScrollStrategy() { 630 return mFocusScrollStrategy; 631 } 632 633 public void setFocusScrollStrategy(int focusScrollStrategy) { 634 mFocusScrollStrategy = focusScrollStrategy; 635 } 636 637 public void setWindowAlignment(int windowAlignment) { 638 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 639 } 640 641 public int getWindowAlignment() { 642 return mWindowAlignment.mainAxis().getWindowAlignment(); 643 } 644 645 public void setWindowAlignmentOffset(int alignmentOffset) { 646 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 647 } 648 649 public int getWindowAlignmentOffset() { 650 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 651 } 652 653 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 654 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 655 } 656 657 public float getWindowAlignmentOffsetPercent() { 658 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 659 } 660 661 public void setItemAlignmentOffset(int alignmentOffset) { 662 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 663 updateChildAlignments(); 664 } 665 666 public int getItemAlignmentOffset() { 667 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 668 } 669 670 public void setItemAlignmentOffsetWithPadding(boolean withPadding) { 671 mItemAlignment.mainAxis().setItemAlignmentOffsetWithPadding(withPadding); 672 updateChildAlignments(); 673 } 674 675 public boolean isItemAlignmentOffsetWithPadding() { 676 return mItemAlignment.mainAxis().isItemAlignmentOffsetWithPadding(); 677 } 678 679 public void setItemAlignmentOffsetPercent(float offsetPercent) { 680 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 681 updateChildAlignments(); 682 } 683 684 public float getItemAlignmentOffsetPercent() { 685 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 686 } 687 688 public void setItemAlignmentViewId(int viewId) { 689 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 690 updateChildAlignments(); 691 } 692 693 public int getItemAlignmentViewId() { 694 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 695 } 696 697 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 698 mFocusOutFront = throughFront; 699 mFocusOutEnd = throughEnd; 700 } 701 702 public void setNumRows(int numRows) { 703 if (numRows < 0) throw new IllegalArgumentException(); 704 mNumRowsRequested = numRows; 705 mForceFullLayout = true; 706 } 707 708 /** 709 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 710 */ 711 public void setRowHeight(int height) { 712 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 713 mRowSizeSecondaryRequested = height; 714 } else { 715 throw new IllegalArgumentException("Invalid row height: " + height); 716 } 717 } 718 719 public void setItemMargin(int margin) { 720 mVerticalMargin = mHorizontalMargin = margin; 721 mMarginPrimary = mMarginSecondary = margin; 722 } 723 724 public void setVerticalMargin(int margin) { 725 if (mOrientation == HORIZONTAL) { 726 mMarginSecondary = mVerticalMargin = margin; 727 } else { 728 mMarginPrimary = mVerticalMargin = margin; 729 } 730 } 731 732 public void setHorizontalMargin(int margin) { 733 if (mOrientation == HORIZONTAL) { 734 mMarginPrimary = mHorizontalMargin = margin; 735 } else { 736 mMarginSecondary = mHorizontalMargin = margin; 737 } 738 } 739 740 public int getVerticalMargin() { 741 return mVerticalMargin; 742 } 743 744 public int getHorizontalMargin() { 745 return mHorizontalMargin; 746 } 747 748 public void setGravity(int gravity) { 749 mGravity = gravity; 750 } 751 752 protected boolean hasDoneFirstLayout() { 753 return mGrid != null; 754 } 755 756 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 757 mChildSelectedListener = listener; 758 } 759 760 void setOnChildLaidOutListener(OnChildLaidOutListener listener) { 761 mChildLaidOutListener = listener; 762 } 763 764 private int getPositionByView(View view) { 765 if (view == null) { 766 return NO_POSITION; 767 } 768 LayoutParams params = (LayoutParams) view.getLayoutParams(); 769 if (params == null || params.isItemRemoved()) { 770 // when item is removed, the position value can be any value. 771 return NO_POSITION; 772 } 773 return params.getViewPosition(); 774 } 775 776 private int getPositionByIndex(int index) { 777 return getPositionByView(getChildAt(index)); 778 } 779 780 private void dispatchChildSelected() { 781 if (mChildSelectedListener == null) { 782 return; 783 } 784 785 if (TRACE) TraceHelper.beginSection("onChildSelected"); 786 View view = mFocusPosition == NO_POSITION ? null : findViewByPosition(mFocusPosition); 787 if (view != null) { 788 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(view); 789 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 790 vh == null? NO_ID: vh.getItemId()); 791 } else { 792 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 793 } 794 if (TRACE) TraceHelper.endSection(); 795 796 // Children may request layout when a child selection event occurs (such as a change of 797 // padding on the current and previously selected rows). 798 // If in layout, a child requesting layout may have been laid out before the selection 799 // callback. 800 // If it was not, the child will be laid out after the selection callback. 801 // If so, the layout request will be honoured though the view system will emit a double- 802 // layout warning. 803 // If not in layout, we may be scrolling in which case the child layout request will be 804 // eaten by recyclerview. Post a requestLayout. 805 if (!mInLayout && !mBaseGridView.isLayoutRequested()) { 806 int childCount = getChildCount(); 807 for (int i = 0; i < childCount; i++) { 808 if (getChildAt(i).isLayoutRequested()) { 809 forceRequestLayout(); 810 break; 811 } 812 } 813 } 814 } 815 816 @Override 817 public boolean canScrollHorizontally() { 818 // We can scroll horizontally if we have horizontal orientation, or if 819 // we are vertical and have more than one column. 820 return mOrientation == HORIZONTAL || mNumRows > 1; 821 } 822 823 @Override 824 public boolean canScrollVertically() { 825 // We can scroll vertically if we have vertical orientation, or if we 826 // are horizontal and have more than one row. 827 return mOrientation == VERTICAL || mNumRows > 1; 828 } 829 830 @Override 831 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 832 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 833 ViewGroup.LayoutParams.WRAP_CONTENT); 834 } 835 836 @Override 837 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 838 return new LayoutParams(context, attrs); 839 } 840 841 @Override 842 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 843 if (lp instanceof LayoutParams) { 844 return new LayoutParams((LayoutParams) lp); 845 } else if (lp instanceof RecyclerView.LayoutParams) { 846 return new LayoutParams((RecyclerView.LayoutParams) lp); 847 } else if (lp instanceof MarginLayoutParams) { 848 return new LayoutParams((MarginLayoutParams) lp); 849 } else { 850 return new LayoutParams(lp); 851 } 852 } 853 854 protected View getViewForPosition(int position) { 855 return mRecycler.getViewForPosition(position); 856 } 857 858 final int getOpticalLeft(View v) { 859 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 860 } 861 862 final int getOpticalRight(View v) { 863 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 864 } 865 866 final int getOpticalTop(View v) { 867 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 868 } 869 870 final int getOpticalBottom(View v) { 871 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 872 } 873 874 private int getViewMin(View v) { 875 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 876 } 877 878 private int getViewMax(View v) { 879 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 880 } 881 882 private int getViewCenter(View view) { 883 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 884 } 885 886 private int getViewCenterSecondary(View view) { 887 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 888 } 889 890 private int getViewCenterX(View v) { 891 LayoutParams p = (LayoutParams) v.getLayoutParams(); 892 return p.getOpticalLeft(v) + p.getAlignX(); 893 } 894 895 private int getViewCenterY(View v) { 896 LayoutParams p = (LayoutParams) v.getLayoutParams(); 897 return p.getOpticalTop(v) + p.getAlignY(); 898 } 899 900 /** 901 * Save Recycler and State for convenience. Must be paired with leaveContext(). 902 */ 903 private void saveContext(Recycler recycler, State state) { 904 if (mRecycler != null || mState != null) { 905 Log.e(TAG, "Recycler information was not released, bug!"); 906 } 907 mRecycler = recycler; 908 mState = state; 909 } 910 911 /** 912 * Discard saved Recycler and State. 913 */ 914 private void leaveContext() { 915 mRecycler = null; 916 mState = null; 917 } 918 919 /** 920 * Re-initialize data structures for a data change or handling invisible 921 * selection. The method tries its best to preserve position information so 922 * that staggered grid looks same before and after re-initialize. 923 * @return true if can fastRelayout() 924 */ 925 private boolean layoutInit() { 926 if (!mState.didStructureChange() && !mForceFullLayout && mGrid != null) { 927 updateScrollController(); 928 updateScrollSecondAxis(); 929 mGrid.setMargin(mMarginPrimary); 930 return true; 931 } else { 932 mForceFullLayout = false; 933 boolean focusViewWasInTree = mGrid != null && mFocusPosition >= 0 934 && mFocusPosition >= mGrid.getFirstVisibleIndex() 935 && mFocusPosition <= mGrid.getLastVisibleIndex(); 936 int firstVisibleIndex = focusViewWasInTree ? mGrid.getFirstVisibleIndex() : 0; 937 final int newItemCount = mState.getItemCount(); 938 if (newItemCount == 0) { 939 mFocusPosition = NO_POSITION; 940 } else if (mFocusPosition >= newItemCount) { 941 mFocusPosition = newItemCount - 1; 942 } else if (mFocusPosition == NO_POSITION && newItemCount > 0) { 943 // if focus position is never set before, initialize it to 0 944 mFocusPosition = 0; 945 } 946 947 if (mGrid == null || mNumRows != mGrid.getNumRows() || 948 mReverseFlowPrimary != mGrid.isReversedFlow()) { 949 mGrid = Grid.createStaggeredMultipleRows(mNumRows); 950 mGrid.setProvider(mGridProvider); 951 mGrid.setReversedFlow(mReverseFlowPrimary); 952 } 953 initScrollController(); 954 updateScrollSecondAxis(); 955 mGrid.setMargin(mMarginPrimary); 956 detachAndScrapAttachedViews(mRecycler); 957 mGrid.resetVisibleIndex(); 958 if (mFocusPosition == NO_POSITION) { 959 mBaseGridView.clearFocus(); 960 } 961 mWindowAlignment.mainAxis().invalidateScrollMin(); 962 mWindowAlignment.mainAxis().invalidateScrollMax(); 963 if (focusViewWasInTree && firstVisibleIndex <= mFocusPosition) { 964 // if focusView was in tree, we will add item from first visible item 965 mGrid.setStart(firstVisibleIndex); 966 } else { 967 // if focusView was not in tree, it's probably because focus position jumped 968 // far away from visible range, so use mFocusPosition as start 969 mGrid.setStart(mFocusPosition); 970 } 971 return false; 972 } 973 } 974 975 private int getRowSizeSecondary(int rowIndex) { 976 if (mFixedRowSizeSecondary != 0) { 977 return mFixedRowSizeSecondary; 978 } 979 if (mRowSizeSecondary == null) { 980 return 0; 981 } 982 return mRowSizeSecondary[rowIndex]; 983 } 984 985 private int getRowStartSecondary(int rowIndex) { 986 int start = 0; 987 // Iterate from left to right, which is a different index traversal 988 // in RTL flow 989 if (mReverseFlowSecondary) { 990 for (int i = mNumRows-1; i > rowIndex; i--) { 991 start += getRowSizeSecondary(i) + mMarginSecondary; 992 } 993 } else { 994 for (int i = 0; i < rowIndex; i++) { 995 start += getRowSizeSecondary(i) + mMarginSecondary; 996 } 997 } 998 return start; 999 } 1000 1001 private int getSizeSecondary() { 1002 int rightmostIndex = mReverseFlowSecondary ? 0 : mNumRows - 1; 1003 return getRowStartSecondary(rightmostIndex) + getRowSizeSecondary(rightmostIndex); 1004 } 1005 1006 private void measureScrapChild(int position, int widthSpec, int heightSpec, 1007 int[] measuredDimension) { 1008 View view = mRecycler.getViewForPosition(position); 1009 if (view != null) { 1010 LayoutParams p = (LayoutParams) view.getLayoutParams(); 1011 int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, 1012 getPaddingLeft() + getPaddingRight(), p.width); 1013 int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, 1014 getPaddingTop() + getPaddingBottom(), p.height); 1015 view.measure(childWidthSpec, childHeightSpec); 1016 measuredDimension[0] = view.getMeasuredWidth(); 1017 measuredDimension[1] = view.getMeasuredHeight(); 1018 mRecycler.recycleView(view); 1019 } 1020 } 1021 1022 private boolean processRowSizeSecondary(boolean measure) { 1023 if (mFixedRowSizeSecondary != 0) { 1024 return false; 1025 } 1026 1027 if (TRACE) TraceHelper.beginSection("processRowSizeSecondary"); 1028 CircularIntArray[] rows = mGrid == null ? null : mGrid.getItemPositionsInRows(); 1029 boolean changed = false; 1030 int scrapChildWidth = -1; 1031 int scrapChildHeight = -1; 1032 1033 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 1034 CircularIntArray row = rows == null ? null : rows[rowIndex]; 1035 final int rowItemsPairCount = row == null ? 0 : row.size(); 1036 int rowSize = -1; 1037 for (int rowItemPairIndex = 0; rowItemPairIndex < rowItemsPairCount; 1038 rowItemPairIndex += 2) { 1039 final int rowIndexStart = row.get(rowItemPairIndex); 1040 final int rowIndexEnd = row.get(rowItemPairIndex + 1); 1041 for (int i = rowIndexStart; i <= rowIndexEnd; i++) { 1042 final View view = findViewByPosition(i); 1043 if (view == null) { 1044 continue; 1045 } 1046 if (measure && view.isLayoutRequested()) { 1047 measureChild(view); 1048 } 1049 final int secondarySize = mOrientation == HORIZONTAL ? 1050 view.getMeasuredHeight() : view.getMeasuredWidth(); 1051 if (secondarySize > rowSize) { 1052 rowSize = secondarySize; 1053 } 1054 } 1055 } 1056 1057 final int itemCount = mState.getItemCount(); 1058 if (measure && rowSize < 0 && itemCount > 0) { 1059 if (scrapChildWidth < 0 && scrapChildHeight < 0) { 1060 int position; 1061 if (mFocusPosition == NO_POSITION) { 1062 position = 0; 1063 } else if (mFocusPosition >= itemCount) { 1064 position = itemCount - 1; 1065 } else { 1066 position = mFocusPosition; 1067 } 1068 measureScrapChild(position, 1069 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1070 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1071 mMeasuredDimension); 1072 scrapChildWidth = mMeasuredDimension[0]; 1073 scrapChildHeight = mMeasuredDimension[1]; 1074 if (DEBUG) Log.v(TAG, "measured scrap child: " + scrapChildWidth + 1075 " " + scrapChildHeight); 1076 } 1077 rowSize = mOrientation == HORIZONTAL ? scrapChildHeight : scrapChildWidth; 1078 } 1079 if (rowSize < 0) { 1080 rowSize = 0; 1081 } 1082 if (mRowSizeSecondary[rowIndex] != rowSize) { 1083 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 1084 ", " + rowSize); 1085 mRowSizeSecondary[rowIndex] = rowSize; 1086 changed = true; 1087 } 1088 } 1089 1090 if (TRACE) TraceHelper.endSection(); 1091 return changed; 1092 } 1093 1094 /** 1095 * Checks if we need to update row secondary sizes. 1096 */ 1097 private void updateRowSecondarySizeRefresh() { 1098 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 1099 if (mRowSecondarySizeRefresh) { 1100 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 1101 forceRequestLayout(); 1102 } 1103 } 1104 1105 private void forceRequestLayout() { 1106 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 1107 // RecyclerView prevents us from requesting layout in many cases 1108 // (during layout, during scroll, etc.) 1109 // For secondary row size wrap_content support we currently need a 1110 // second layout pass to update the measured size after having measured 1111 // and added child views in layoutChildren. 1112 // Force the second layout by posting a delayed runnable. 1113 // TODO: investigate allowing a second layout pass, 1114 // or move child add/measure logic to the measure phase. 1115 ViewCompat.postOnAnimation(mBaseGridView, mRequestLayoutRunnable); 1116 } 1117 1118 private final Runnable mRequestLayoutRunnable = new Runnable() { 1119 @Override 1120 public void run() { 1121 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 1122 requestLayout(); 1123 } 1124 }; 1125 1126 @Override 1127 public void onMeasure(Recycler recycler, State state, int widthSpec, int heightSpec) { 1128 saveContext(recycler, state); 1129 1130 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 1131 int measuredSizeSecondary; 1132 if (mOrientation == HORIZONTAL) { 1133 sizePrimary = MeasureSpec.getSize(widthSpec); 1134 sizeSecondary = MeasureSpec.getSize(heightSpec); 1135 modeSecondary = MeasureSpec.getMode(heightSpec); 1136 paddingSecondary = getPaddingTop() + getPaddingBottom(); 1137 } else { 1138 sizeSecondary = MeasureSpec.getSize(widthSpec); 1139 sizePrimary = MeasureSpec.getSize(heightSpec); 1140 modeSecondary = MeasureSpec.getMode(widthSpec); 1141 paddingSecondary = getPaddingLeft() + getPaddingRight(); 1142 } 1143 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 1144 " heightSpec " + Integer.toHexString(heightSpec) + 1145 " modeSecondary " + Integer.toHexString(modeSecondary) + 1146 " sizeSecondary " + sizeSecondary + " " + this); 1147 1148 mMaxSizeSecondary = sizeSecondary; 1149 1150 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 1151 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1152 mFixedRowSizeSecondary = 0; 1153 1154 if (mRowSizeSecondary == null || mRowSizeSecondary.length != mNumRows) { 1155 mRowSizeSecondary = new int[mNumRows]; 1156 } 1157 1158 // Measure all current children and update cached row heights 1159 processRowSizeSecondary(true); 1160 1161 switch (modeSecondary) { 1162 case MeasureSpec.UNSPECIFIED: 1163 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 1164 break; 1165 case MeasureSpec.AT_MOST: 1166 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 1167 mMaxSizeSecondary); 1168 break; 1169 case MeasureSpec.EXACTLY: 1170 measuredSizeSecondary = mMaxSizeSecondary; 1171 break; 1172 default: 1173 throw new IllegalStateException("wrong spec"); 1174 } 1175 1176 } else { 1177 switch (modeSecondary) { 1178 case MeasureSpec.UNSPECIFIED: 1179 if (mRowSizeSecondaryRequested == 0) { 1180 if (mOrientation == HORIZONTAL) { 1181 throw new IllegalStateException("Must specify rowHeight or view height"); 1182 } else { 1183 throw new IllegalStateException("Must specify columnWidth or view width"); 1184 } 1185 } 1186 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1187 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1188 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1189 * (mNumRows - 1) + paddingSecondary; 1190 break; 1191 case MeasureSpec.AT_MOST: 1192 case MeasureSpec.EXACTLY: 1193 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 1194 mNumRows = 1; 1195 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 1196 } else if (mNumRowsRequested == 0) { 1197 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1198 mNumRows = (sizeSecondary + mMarginSecondary) 1199 / (mRowSizeSecondaryRequested + mMarginSecondary); 1200 } else if (mRowSizeSecondaryRequested == 0) { 1201 mNumRows = mNumRowsRequested; 1202 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 1203 * (mNumRows - 1)) / mNumRows; 1204 } else { 1205 mNumRows = mNumRowsRequested; 1206 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1207 } 1208 measuredSizeSecondary = sizeSecondary; 1209 if (modeSecondary == MeasureSpec.AT_MOST) { 1210 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1211 * (mNumRows - 1) + paddingSecondary; 1212 if (childrenSize < measuredSizeSecondary) { 1213 measuredSizeSecondary = childrenSize; 1214 } 1215 } 1216 break; 1217 default: 1218 throw new IllegalStateException("wrong spec"); 1219 } 1220 } 1221 if (mOrientation == HORIZONTAL) { 1222 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1223 } else { 1224 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1225 } 1226 if (DEBUG) { 1227 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1228 " measuredSizeSecondary " + measuredSizeSecondary + 1229 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1230 " mNumRows " + mNumRows); 1231 } 1232 leaveContext(); 1233 } 1234 1235 private void measureChild(View child) { 1236 if (TRACE) TraceHelper.beginSection("measureChild"); 1237 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1238 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1239 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1240 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1241 int widthSpec, heightSpec; 1242 1243 if (mOrientation == HORIZONTAL) { 1244 widthSpec = ViewGroup.getChildMeasureSpec( 1245 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1246 0, lp.width); 1247 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1248 } else { 1249 heightSpec = ViewGroup.getChildMeasureSpec( 1250 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1251 0, lp.height); 1252 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1253 } 1254 child.measure(widthSpec, heightSpec); 1255 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1256 " widthSpec " + Integer.toHexString(widthSpec) + 1257 " heightSpec " + Integer.toHexString(heightSpec) + 1258 " measuredWidth " + child.getMeasuredWidth() + 1259 " measuredHeight " + child.getMeasuredHeight()); 1260 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1261 if (TRACE) TraceHelper.endSection(); 1262 } 1263 1264 private Grid.Provider mGridProvider = new Grid.Provider() { 1265 1266 @Override 1267 public int getCount() { 1268 return mState.getItemCount(); 1269 } 1270 1271 @Override 1272 public int createItem(int index, boolean append, Object[] item) { 1273 if (TRACE) TraceHelper.beginSection("createItem"); 1274 if (TRACE) TraceHelper.beginSection("getview"); 1275 View v = getViewForPosition(index); 1276 if (TRACE) TraceHelper.endSection(); 1277 // See recyclerView docs: we don't need re-add scraped view if it was removed. 1278 if (!((RecyclerView.LayoutParams) v.getLayoutParams()).isItemRemoved()) { 1279 if (TRACE) TraceHelper.beginSection("addView"); 1280 if (append) { 1281 addView(v); 1282 } else { 1283 addView(v, 0); 1284 } 1285 if (TRACE) TraceHelper.endSection(); 1286 if (mChildVisibility != -1) { 1287 v.setVisibility(mChildVisibility); 1288 } 1289 1290 if (mPendingMoveSmoothScroller != null) { 1291 mPendingMoveSmoothScroller.consumePendingMovesBeforeLayout(); 1292 } 1293 if (!mInLayout) { 1294 // when we are appending item during scroll pass and the item's position 1295 // matches the mFocusPosition, we should signal a childSelected event. 1296 // However if we are still running PendingMoveSmoothScroller, we defer and 1297 // signal the event in PendingMoveSmoothScroller.onStop(). This can 1298 // avoid lots of childSelected events during a long smooth scrolling and 1299 // increase performance. 1300 if (index == mFocusPosition && (mPendingMoveSmoothScroller == null 1301 || mPendingMoveSmoothScroller.mPendingMoves == 0)) { 1302 dispatchChildSelected(); 1303 } 1304 } else if (!mInFastRelayout) { 1305 // fastRelayout will dispatch event at end of onLayoutChildren(). 1306 // For full layout, two situations here: 1307 // 1. mInLayoutSearchFocus is false, dispatchChildSelected() at mFocusPosition. 1308 // 2. mInLayoutSearchFocus is true: dispatchChildSelected() on first child 1309 // equal to or after mFocusPosition that can take focus. 1310 if (!mInLayoutSearchFocus && index == mFocusPosition) { 1311 dispatchChildSelected(); 1312 } else if (mInLayoutSearchFocus && index >= mFocusPosition 1313 && v.hasFocusable()) { 1314 mFocusPosition = index; 1315 mInLayoutSearchFocus = false; 1316 dispatchChildSelected(); 1317 } 1318 } 1319 measureChild(v); 1320 } 1321 item[0] = v; 1322 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1323 } 1324 1325 @Override 1326 public void addItem(Object item, int index, int length, int rowIndex, int edge) { 1327 View v = (View) item; 1328 int start, end; 1329 if (edge == Integer.MIN_VALUE || edge == Integer.MAX_VALUE) { 1330 edge = !mGrid.isReversedFlow() ? mWindowAlignment.mainAxis().getPaddingLow() 1331 : mWindowAlignment.mainAxis().getSize() 1332 - mWindowAlignment.mainAxis().getPaddingHigh(); 1333 } 1334 boolean edgeIsMin = !mGrid.isReversedFlow(); 1335 if (edgeIsMin) { 1336 start = edge; 1337 end = edge + length; 1338 } else { 1339 start = edge - length; 1340 end = edge; 1341 } 1342 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1343 mChildrenStates.loadView(v, index); 1344 layoutChild(rowIndex, v, start, end, startSecondary); 1345 if (DEBUG) { 1346 Log.d(getTag(), "addView " + index + " " + v); 1347 } 1348 if (TRACE) TraceHelper.endSection(); 1349 1350 if (index == mGrid.getFirstVisibleIndex()) { 1351 if (!mGrid.isReversedFlow()) { 1352 updateScrollMin(); 1353 } else { 1354 updateScrollMax(); 1355 } 1356 } 1357 if (index == mGrid.getLastVisibleIndex()) { 1358 if (!mGrid.isReversedFlow()) { 1359 updateScrollMax(); 1360 } else { 1361 updateScrollMin(); 1362 } 1363 } 1364 if (!mInLayout && mPendingMoveSmoothScroller != null) { 1365 mPendingMoveSmoothScroller.consumePendingMovesAfterLayout(); 1366 } 1367 if (mChildLaidOutListener != null) { 1368 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(v); 1369 mChildLaidOutListener.onChildLaidOut(mBaseGridView, v, index, 1370 vh == null ? NO_ID : vh.getItemId()); 1371 } 1372 } 1373 1374 @Override 1375 public void removeItem(int index) { 1376 if (TRACE) TraceHelper.beginSection("removeItem"); 1377 View v = findViewByPosition(index); 1378 if (mInLayout) { 1379 detachAndScrapView(v, mRecycler); 1380 } else { 1381 removeAndRecycleView(v, mRecycler); 1382 } 1383 if (TRACE) TraceHelper.endSection(); 1384 } 1385 1386 @Override 1387 public int getEdge(int index) { 1388 if (mReverseFlowPrimary) { 1389 return getViewMax(findViewByPosition(index)); 1390 } else { 1391 return getViewMin(findViewByPosition(index)); 1392 } 1393 } 1394 1395 @Override 1396 public int getSize(int index) { 1397 final View v = findViewByPosition(index); 1398 return mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1399 } 1400 }; 1401 1402 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1403 if (TRACE) TraceHelper.beginSection("layoutChild"); 1404 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1405 : v.getMeasuredWidth(); 1406 if (mFixedRowSizeSecondary > 0) { 1407 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1408 } 1409 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1410 final int horizontalGravity = (mReverseFlowPrimary || mReverseFlowSecondary) ? 1411 Gravity.getAbsoluteGravity(mGravity & Gravity.RELATIVE_HORIZONTAL_GRAVITY_MASK, View.LAYOUT_DIRECTION_RTL) : 1412 mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1413 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1414 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1415 // do nothing 1416 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1417 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1418 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1419 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1420 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1421 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1422 } 1423 int left, top, right, bottom; 1424 if (mOrientation == HORIZONTAL) { 1425 left = start; 1426 top = startSecondary; 1427 right = end; 1428 bottom = startSecondary + sizeSecondary; 1429 } else { 1430 top = start; 1431 left = startSecondary; 1432 bottom = end; 1433 right = startSecondary + sizeSecondary; 1434 } 1435 v.layout(left, top, right, bottom); 1436 updateChildOpticalInsets(v, left, top, right, bottom); 1437 updateChildAlignments(v); 1438 if (TRACE) TraceHelper.endSection(); 1439 } 1440 1441 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1442 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1443 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1444 v.getRight() - right, v.getBottom() - bottom); 1445 } 1446 1447 private void updateChildAlignments(View v) { 1448 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1449 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1450 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1451 } 1452 1453 private void updateChildAlignments() { 1454 for (int i = 0, c = getChildCount(); i < c; i++) { 1455 updateChildAlignments(getChildAt(i)); 1456 } 1457 } 1458 1459 private void removeInvisibleViewsAtEnd() { 1460 if (mPruneChild) { 1461 mGrid.removeInvisibleItemsAtEnd(mFocusPosition, 1462 mReverseFlowPrimary ? 0 : mSizePrimary); 1463 } 1464 } 1465 1466 private void removeInvisibleViewsAtFront() { 1467 if (mPruneChild) { 1468 mGrid.removeInvisibleItemsAtFront(mFocusPosition, 1469 mReverseFlowPrimary ? mSizePrimary : 0); 1470 } 1471 } 1472 1473 private boolean appendOneColumnVisibleItems() { 1474 return mGrid.appendOneColumnVisibleItems(); 1475 } 1476 1477 private boolean prependOneColumnVisibleItems() { 1478 return mGrid.prependOneColumnVisibleItems(); 1479 } 1480 1481 private void appendVisibleItems() { 1482 mGrid.appendVisibleItems(mReverseFlowPrimary ? 0 : mSizePrimary); 1483 } 1484 1485 private void prependVisibleItems() { 1486 mGrid.prependVisibleItems(mReverseFlowPrimary ? mSizePrimary : 0); 1487 } 1488 1489 /** 1490 * Fast layout when there is no structure change, adapter change, etc. 1491 * It will layout all views was layout requested or updated, until hit a view 1492 * with different size, then it break and detachAndScrap all views after that. 1493 */ 1494 private void fastRelayout() { 1495 boolean invalidateAfter = false; 1496 final int childCount = getChildCount(); 1497 int position = -1; 1498 for (int index = 0; index < childCount; index++) { 1499 View view = getChildAt(index); 1500 position = getPositionByIndex(index); 1501 Grid.Location location = mGrid.getLocation(position); 1502 if (location == null) { 1503 if (DEBUG) Log.w(getTag(), "fastRelayout(): no Location at " + position); 1504 invalidateAfter = true; 1505 break; 1506 } 1507 1508 int startSecondary = getRowStartSecondary(location.row) - mScrollOffsetSecondary; 1509 int primarySize, end; 1510 int start = getViewMin(view); 1511 int oldPrimarySize = (mOrientation == HORIZONTAL) ? 1512 view.getMeasuredWidth() : 1513 view.getMeasuredHeight(); 1514 1515 LayoutParams lp = (LayoutParams) view.getLayoutParams(); 1516 if (lp.viewNeedsUpdate()) { 1517 int viewIndex = mBaseGridView.indexOfChild(view); 1518 detachAndScrapView(view, mRecycler); 1519 view = getViewForPosition(position); 1520 addView(view, viewIndex); 1521 } 1522 1523 if (view.isLayoutRequested()) { 1524 measureChild(view); 1525 } 1526 if (mOrientation == HORIZONTAL) { 1527 primarySize = view.getMeasuredWidth(); 1528 end = start + primarySize; 1529 } else { 1530 primarySize = view.getMeasuredHeight(); 1531 end = start + primarySize; 1532 } 1533 layoutChild(location.row, view, start, end, startSecondary); 1534 if (oldPrimarySize != primarySize) { 1535 // size changed invalidate remaining Locations 1536 if (DEBUG) Log.d(getTag(), "fastRelayout: view size changed at " + position); 1537 invalidateAfter = true; 1538 break; 1539 } 1540 } 1541 if (invalidateAfter) { 1542 final int savedLastPos = mGrid.getLastVisibleIndex(); 1543 mGrid.invalidateItemsAfter(position); 1544 if (mPruneChild) { 1545 // in regular prune child mode, we just append items up to edge limit 1546 appendVisibleItems(); 1547 if (mFocusPosition >= 0 && mFocusPosition <= savedLastPos) { 1548 // make sure add focus view back: the view might be outside edge limit 1549 // when there is delta in onLayoutChildren(). 1550 while (mGrid.getLastVisibleIndex() < mFocusPosition) { 1551 mGrid.appendOneColumnVisibleItems(); 1552 } 1553 } 1554 } else { 1555 // prune disabled(e.g. in RowsFragment transition): append all removed items 1556 while (mGrid.appendOneColumnVisibleItems() 1557 && mGrid.getLastVisibleIndex() < savedLastPos); 1558 } 1559 } 1560 updateScrollMin(); 1561 updateScrollMax(); 1562 updateScrollSecondAxis(); 1563 } 1564 1565 public void removeAndRecycleAllViews(RecyclerView.Recycler recycler) { 1566 if (TRACE) TraceHelper.beginSection("removeAndRecycleAllViews"); 1567 if (DEBUG) Log.v(TAG, "removeAndRecycleAllViews " + getChildCount()); 1568 for (int i = getChildCount() - 1; i >= 0; i--) { 1569 removeAndRecycleViewAt(i, recycler); 1570 } 1571 if (TRACE) TraceHelper.endSection(); 1572 } 1573 1574 // Lays out items based on the current scroll position 1575 @Override 1576 public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) { 1577 if (DEBUG) { 1578 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1579 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1580 + " inPreLayout " + state.isPreLayout() 1581 + " didStructureChange " + state.didStructureChange() 1582 + " mForceFullLayout " + mForceFullLayout); 1583 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1584 } 1585 1586 if (mNumRows == 0) { 1587 // haven't done measure yet 1588 return; 1589 } 1590 final int itemCount = state.getItemCount(); 1591 if (itemCount < 0) { 1592 return; 1593 } 1594 1595 if (!mLayoutEnabled) { 1596 discardLayoutInfo(); 1597 removeAndRecycleAllViews(recycler); 1598 return; 1599 } 1600 mInLayout = true; 1601 1602 final boolean scrollToFocus = !isSmoothScrolling() 1603 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED; 1604 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1605 mFocusPosition = mFocusPosition + mFocusPositionOffset; 1606 mFocusPositionOffset = 0; 1607 } 1608 saveContext(recycler, state); 1609 1610 // Track the old focus view so we can adjust our system scroll position 1611 // so that any scroll animations happening now will remain valid. 1612 // We must use same delta in Pre Layout (if prelayout exists) and second layout. 1613 // So we cache the deltas in PreLayout and use it in second layout. 1614 int delta = 0, deltaSecondary = 0; 1615 if (mFocusPosition != NO_POSITION && scrollToFocus 1616 && mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE) { 1617 // FIXME: we should get the remaining scroll animation offset from RecyclerView 1618 View focusView = findViewByPosition(mFocusPosition); 1619 if (focusView != null) { 1620 delta = mWindowAlignment.mainAxis().getSystemScrollPos(mScrollOffsetPrimary 1621 + getViewCenter(focusView), false, false) - mScrollOffsetPrimary; 1622 deltaSecondary = mWindowAlignment.secondAxis().getSystemScrollPos( 1623 mScrollOffsetSecondary + getViewCenterSecondary(focusView), 1624 false, false) - mScrollOffsetSecondary; 1625 } 1626 } 1627 1628 boolean hadFocus = mBaseGridView.hasFocus(); 1629 int savedFocusPos = mFocusPosition; 1630 if (mInFastRelayout = layoutInit()) { 1631 fastRelayout(); 1632 View focusView = findViewByPosition(mFocusPosition); 1633 if (scrollToFocus) { 1634 scrollToView(focusView, false); 1635 } 1636 if (focusView != null && hadFocus) { 1637 focusView.requestFocus(); 1638 } 1639 } else { 1640 mInLayoutSearchFocus = hadFocus; 1641 if (mFocusPosition != NO_POSITION) { 1642 // appends items till focus position. 1643 while (appendOneColumnVisibleItems() 1644 && findViewByPosition(mFocusPosition) == null) ; 1645 } 1646 // multiple rounds: scrollToView of first round may drag first/last child into 1647 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1648 int oldFirstVisible; 1649 int oldLastVisible; 1650 do { 1651 updateScrollMin(); 1652 updateScrollMax(); 1653 oldFirstVisible = mGrid.getFirstVisibleIndex(); 1654 oldLastVisible = mGrid.getLastVisibleIndex(); 1655 View focusView = findViewByPosition(mFocusPosition); 1656 // we need force to initialize the child view's position 1657 scrollToView(focusView, false); 1658 if (focusView != null && hadFocus) { 1659 focusView.requestFocus(); 1660 } 1661 appendVisibleItems(); 1662 prependVisibleItems(); 1663 removeInvisibleViewsAtFront(); 1664 removeInvisibleViewsAtEnd(); 1665 } while (mGrid.getFirstVisibleIndex() != oldFirstVisible || 1666 mGrid.getLastVisibleIndex() != oldLastVisible); 1667 } 1668 1669 if (scrollToFocus) { 1670 scrollDirectionPrimary(-delta); 1671 scrollDirectionSecondary(-deltaSecondary); 1672 } 1673 appendVisibleItems(); 1674 prependVisibleItems(); 1675 removeInvisibleViewsAtFront(); 1676 removeInvisibleViewsAtEnd(); 1677 1678 if (DEBUG) { 1679 StringWriter sw = new StringWriter(); 1680 PrintWriter pw = new PrintWriter(sw); 1681 mGrid.debugPrint(pw); 1682 Log.d(getTag(), sw.toString()); 1683 } 1684 1685 if (mRowSecondarySizeRefresh) { 1686 mRowSecondarySizeRefresh = false; 1687 } else { 1688 updateRowSecondarySizeRefresh(); 1689 } 1690 1691 // For fastRelayout, only dispatch event when focus position changes. 1692 if (mInFastRelayout && mFocusPosition != savedFocusPos) { 1693 dispatchChildSelected(); 1694 } else if (!mInFastRelayout && mInLayoutSearchFocus) { 1695 // For full layout we dispatchChildSelected() in createItem() unless searched all 1696 // children and found none is focusable then dispatchChildSelected() here. 1697 dispatchChildSelected(); 1698 } 1699 1700 mInLayout = false; 1701 leaveContext(); 1702 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1703 } 1704 1705 private void offsetChildrenSecondary(int increment) { 1706 final int childCount = getChildCount(); 1707 if (mOrientation == HORIZONTAL) { 1708 for (int i = 0; i < childCount; i++) { 1709 getChildAt(i).offsetTopAndBottom(increment); 1710 } 1711 } else { 1712 for (int i = 0; i < childCount; i++) { 1713 getChildAt(i).offsetLeftAndRight(increment); 1714 } 1715 } 1716 } 1717 1718 private void offsetChildrenPrimary(int increment) { 1719 final int childCount = getChildCount(); 1720 if (mOrientation == VERTICAL) { 1721 for (int i = 0; i < childCount; i++) { 1722 getChildAt(i).offsetTopAndBottom(increment); 1723 } 1724 } else { 1725 for (int i = 0; i < childCount; i++) { 1726 getChildAt(i).offsetLeftAndRight(increment); 1727 } 1728 } 1729 } 1730 1731 @Override 1732 public int scrollHorizontallyBy(int dx, Recycler recycler, RecyclerView.State state) { 1733 if (DEBUG) Log.v(getTag(), "scrollHorizontallyBy " + dx); 1734 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1735 return 0; 1736 } 1737 saveContext(recycler, state); 1738 int result; 1739 if (mOrientation == HORIZONTAL) { 1740 result = scrollDirectionPrimary(dx); 1741 } else { 1742 result = scrollDirectionSecondary(dx); 1743 } 1744 leaveContext(); 1745 return result; 1746 } 1747 1748 @Override 1749 public int scrollVerticallyBy(int dy, Recycler recycler, RecyclerView.State state) { 1750 if (DEBUG) Log.v(getTag(), "scrollVerticallyBy " + dy); 1751 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1752 return 0; 1753 } 1754 saveContext(recycler, state); 1755 int result; 1756 if (mOrientation == VERTICAL) { 1757 result = scrollDirectionPrimary(dy); 1758 } else { 1759 result = scrollDirectionSecondary(dy); 1760 } 1761 leaveContext(); 1762 return result; 1763 } 1764 1765 // scroll in main direction may add/prune views 1766 private int scrollDirectionPrimary(int da) { 1767 if (TRACE) TraceHelper.beginSection("scrollPrimary"); 1768 boolean isMaxUnknown = false, isMinUnknown = false; 1769 int minScroll = 0, maxScroll = 0; 1770 if (da > 0) { 1771 isMaxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1772 if (!isMaxUnknown) { 1773 maxScroll = mWindowAlignment.mainAxis().getMaxScroll(); 1774 if (mScrollOffsetPrimary + da > maxScroll) { 1775 da = maxScroll - mScrollOffsetPrimary; 1776 } 1777 } 1778 } else if (da < 0) { 1779 isMinUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1780 if (!isMinUnknown) { 1781 minScroll = mWindowAlignment.mainAxis().getMinScroll(); 1782 if (mScrollOffsetPrimary + da < minScroll) { 1783 da = minScroll - mScrollOffsetPrimary; 1784 } 1785 } 1786 } 1787 if (da == 0) { 1788 if (TRACE) TraceHelper.endSection(); 1789 return 0; 1790 } 1791 offsetChildrenPrimary(-da); 1792 mScrollOffsetPrimary += da; 1793 if (mInLayout) { 1794 if (TRACE) TraceHelper.endSection(); 1795 return da; 1796 } 1797 1798 int childCount = getChildCount(); 1799 boolean updated; 1800 1801 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1802 prependVisibleItems(); 1803 } else { 1804 appendVisibleItems(); 1805 } 1806 updated = getChildCount() > childCount; 1807 childCount = getChildCount(); 1808 1809 if (TRACE) TraceHelper.beginSection("remove"); 1810 if (mReverseFlowPrimary ? da > 0 : da < 0) { 1811 removeInvisibleViewsAtEnd(); 1812 } else { 1813 removeInvisibleViewsAtFront(); 1814 } 1815 if (TRACE) TraceHelper.endSection(); 1816 updated |= getChildCount() < childCount; 1817 if (updated) { 1818 updateRowSecondarySizeRefresh(); 1819 } 1820 1821 mBaseGridView.invalidate(); 1822 if (TRACE) TraceHelper.endSection(); 1823 return da; 1824 } 1825 1826 // scroll in second direction will not add/prune views 1827 private int scrollDirectionSecondary(int dy) { 1828 if (dy == 0) { 1829 return 0; 1830 } 1831 offsetChildrenSecondary(-dy); 1832 mScrollOffsetSecondary += dy; 1833 mBaseGridView.invalidate(); 1834 return dy; 1835 } 1836 1837 private void updateScrollMax() { 1838 int highVisiblePos = (!mReverseFlowPrimary) ? mGrid.getLastVisibleIndex() 1839 : mGrid.getFirstVisibleIndex(); 1840 int highMaxPos = (!mReverseFlowPrimary) ? mState.getItemCount() - 1 : 0; 1841 if (highVisiblePos < 0) { 1842 return; 1843 } 1844 final boolean highAvailable = highVisiblePos == highMaxPos; 1845 final boolean maxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1846 if (!highAvailable && maxUnknown) { 1847 return; 1848 } 1849 int maxEdge = mGrid.findRowMax(true, sTwoInts) + mScrollOffsetPrimary; 1850 int rowIndex = sTwoInts[0]; 1851 int pos = sTwoInts[1]; 1852 int savedMaxEdge = mWindowAlignment.mainAxis().getMaxEdge(); 1853 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1854 int maxScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1855 mWindowAlignment.mainAxis().setMaxEdge(savedMaxEdge); 1856 1857 if (highAvailable) { 1858 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1859 mWindowAlignment.mainAxis().setMaxScroll(maxScroll); 1860 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge + 1861 " scrollMax to " + maxScroll); 1862 } else { 1863 mWindowAlignment.mainAxis().invalidateScrollMax(); 1864 if (DEBUG) Log.v(getTag(), "Invalidate scrollMax since it should be " 1865 + "greater than " + maxScroll); 1866 } 1867 } 1868 1869 private void updateScrollMin() { 1870 int lowVisiblePos = (!mReverseFlowPrimary) ? mGrid.getFirstVisibleIndex() 1871 : mGrid.getLastVisibleIndex(); 1872 int lowMinPos = (!mReverseFlowPrimary) ? 0 : mState.getItemCount() - 1; 1873 if (lowVisiblePos < 0) { 1874 return; 1875 } 1876 final boolean lowAvailable = lowVisiblePos == lowMinPos; 1877 final boolean minUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1878 if (!lowAvailable && minUnknown) { 1879 return; 1880 } 1881 int minEdge = mGrid.findRowMin(false, sTwoInts) + mScrollOffsetPrimary; 1882 int rowIndex = sTwoInts[0]; 1883 int pos = sTwoInts[1]; 1884 int savedMinEdge = mWindowAlignment.mainAxis().getMinEdge(); 1885 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1886 int minScroll = getPrimarySystemScrollPosition(findViewByPosition(pos)); 1887 mWindowAlignment.mainAxis().setMinEdge(savedMinEdge); 1888 1889 if (lowAvailable) { 1890 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1891 mWindowAlignment.mainAxis().setMinScroll(minScroll); 1892 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge + 1893 " scrollMin to " + minScroll); 1894 } else { 1895 mWindowAlignment.mainAxis().invalidateScrollMin(); 1896 if (DEBUG) Log.v(getTag(), "Invalidate scrollMin, since it should be " 1897 + "less than " + minScroll); 1898 } 1899 } 1900 1901 private void updateScrollSecondAxis() { 1902 mWindowAlignment.secondAxis().setMinEdge(0); 1903 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1904 } 1905 1906 private void initScrollController() { 1907 mWindowAlignment.reset(); 1908 mWindowAlignment.horizontal.setSize(getWidth()); 1909 mWindowAlignment.vertical.setSize(getHeight()); 1910 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1911 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1912 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1913 mScrollOffsetPrimary = -mWindowAlignment.mainAxis().getPaddingLow(); 1914 mScrollOffsetSecondary = -mWindowAlignment.secondAxis().getPaddingLow(); 1915 1916 if (DEBUG) { 1917 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1918 + " mWindowAlignment " + mWindowAlignment 1919 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1920 } 1921 } 1922 1923 private void updateScrollController() { 1924 // mScrollOffsetPrimary and mScrollOffsetSecondary includes the padding. 1925 // e.g. when topPadding is 16 for horizontal grid view, the initial 1926 // mScrollOffsetSecondary is -16. fastRelayout() put views based on offsets(not padding), 1927 // when padding changes to 20, we also need update mScrollOffsetSecondary to -20 before 1928 // fastRelayout() is performed 1929 int paddingPrimaryDiff, paddingSecondaryDiff; 1930 if (mOrientation == HORIZONTAL) { 1931 paddingPrimaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1932 paddingSecondaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1933 } else { 1934 paddingPrimaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1935 paddingSecondaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1936 } 1937 mScrollOffsetPrimary -= paddingPrimaryDiff; 1938 mScrollOffsetSecondary -= paddingSecondaryDiff; 1939 1940 mWindowAlignment.horizontal.setSize(getWidth()); 1941 mWindowAlignment.vertical.setSize(getHeight()); 1942 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1943 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1944 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1945 1946 if (DEBUG) { 1947 Log.v(getTag(), "updateScrollController mSizePrimary " + mSizePrimary 1948 + " mWindowAlignment " + mWindowAlignment 1949 + " mScrollOffsetPrimary " + mScrollOffsetPrimary); 1950 } 1951 } 1952 1953 public void setSelection(RecyclerView parent, int position) { 1954 setSelection(parent, position, false); 1955 } 1956 1957 public void setSelectionSmooth(RecyclerView parent, int position) { 1958 setSelection(parent, position, true); 1959 } 1960 1961 public int getSelection() { 1962 return mFocusPosition; 1963 } 1964 1965 public void setSelection(RecyclerView parent, int position, boolean smooth) { 1966 if (mFocusPosition != position && position != NO_POSITION) { 1967 scrollToSelection(parent, position, smooth); 1968 } 1969 } 1970 1971 private void scrollToSelection(RecyclerView parent, int position, boolean smooth) { 1972 if (TRACE) TraceHelper.beginSection("scrollToSelection"); 1973 View view = findViewByPosition(position); 1974 if (view != null) { 1975 mInSelection = true; 1976 scrollToView(view, smooth); 1977 mInSelection = false; 1978 } else { 1979 mFocusPosition = position; 1980 mFocusPositionOffset = 0; 1981 if (!mLayoutEnabled) { 1982 return; 1983 } 1984 if (smooth) { 1985 if (!hasDoneFirstLayout()) { 1986 Log.w(getTag(), "setSelectionSmooth should " + 1987 "not be called before first layout pass"); 1988 return; 1989 } 1990 startPositionSmoothScroller(position); 1991 } else { 1992 mForceFullLayout = true; 1993 parent.requestLayout(); 1994 } 1995 } 1996 if (TRACE) TraceHelper.endSection(); 1997 } 1998 1999 void startPositionSmoothScroller(int position) { 2000 LinearSmoothScroller linearSmoothScroller = new GridLinearSmoothScroller() { 2001 @Override 2002 public PointF computeScrollVectorForPosition(int targetPosition) { 2003 if (getChildCount() == 0) { 2004 return null; 2005 } 2006 final int firstChildPos = getPosition(getChildAt(0)); 2007 // TODO We should be able to deduce direction from bounds of current and target 2008 // focus, rather than making assumptions about positions and directionality 2009 final boolean isStart = mReverseFlowPrimary ? targetPosition > firstChildPos 2010 : targetPosition < firstChildPos; 2011 final int direction = isStart ? -1 : 1; 2012 if (mOrientation == HORIZONTAL) { 2013 return new PointF(direction, 0); 2014 } else { 2015 return new PointF(0, direction); 2016 } 2017 } 2018 2019 }; 2020 linearSmoothScroller.setTargetPosition(position); 2021 startSmoothScroll(linearSmoothScroller); 2022 } 2023 2024 private void processPendingMovement(boolean forward) { 2025 if (forward ? hasCreatedLastItem() : hasCreatedFirstItem()) { 2026 return; 2027 } 2028 if (mPendingMoveSmoothScroller == null) { 2029 // Stop existing scroller and create a new PendingMoveSmoothScroller. 2030 mBaseGridView.stopScroll(); 2031 PendingMoveSmoothScroller linearSmoothScroller = new PendingMoveSmoothScroller( 2032 forward ? 1 : -1, mNumRows > 1); 2033 mFocusPositionOffset = 0; 2034 startSmoothScroll(linearSmoothScroller); 2035 if (linearSmoothScroller.isRunning()) { 2036 mPendingMoveSmoothScroller = linearSmoothScroller; 2037 } 2038 } else { 2039 if (forward) { 2040 mPendingMoveSmoothScroller.increasePendingMoves(); 2041 } else { 2042 mPendingMoveSmoothScroller.decreasePendingMoves(); 2043 } 2044 } 2045 } 2046 2047 @Override 2048 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 2049 if (DEBUG) Log.v(getTag(), "onItemsAdded positionStart " 2050 + positionStart + " itemCount " + itemCount); 2051 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2052 int pos = mFocusPosition + mFocusPositionOffset; 2053 if (positionStart <= pos) { 2054 mFocusPositionOffset += itemCount; 2055 } 2056 } 2057 mChildrenStates.clear(); 2058 } 2059 2060 @Override 2061 public void onItemsChanged(RecyclerView recyclerView) { 2062 if (DEBUG) Log.v(getTag(), "onItemsChanged"); 2063 mFocusPositionOffset = 0; 2064 mChildrenStates.clear(); 2065 } 2066 2067 @Override 2068 public void onItemsRemoved(RecyclerView recyclerView, int positionStart, int itemCount) { 2069 if (DEBUG) Log.v(getTag(), "onItemsRemoved positionStart " 2070 + positionStart + " itemCount " + itemCount); 2071 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2072 int pos = mFocusPosition + mFocusPositionOffset; 2073 if (positionStart <= pos) { 2074 if (positionStart + itemCount > pos) { 2075 // stop updating offset after the focus item was removed 2076 mFocusPositionOffset = Integer.MIN_VALUE; 2077 } else { 2078 mFocusPositionOffset -= itemCount; 2079 } 2080 } 2081 } 2082 mChildrenStates.clear(); 2083 } 2084 2085 @Override 2086 public void onItemsMoved(RecyclerView recyclerView, int fromPosition, int toPosition, 2087 int itemCount) { 2088 if (DEBUG) Log.v(getTag(), "onItemsMoved fromPosition " 2089 + fromPosition + " toPosition " + toPosition); 2090 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 2091 int pos = mFocusPosition + mFocusPositionOffset; 2092 if (fromPosition <= pos && pos < fromPosition + itemCount) { 2093 // moved items include focused position 2094 mFocusPositionOffset += toPosition - fromPosition; 2095 } else if (fromPosition < pos && toPosition > pos - itemCount) { 2096 // move items before focus position to after focused position 2097 mFocusPositionOffset -= itemCount; 2098 } else if (fromPosition > pos && toPosition < pos) { 2099 // move items after focus position to before focused position 2100 mFocusPositionOffset += itemCount; 2101 } 2102 } 2103 mChildrenStates.clear(); 2104 } 2105 2106 @Override 2107 public void onItemsUpdated(RecyclerView recyclerView, int positionStart, int itemCount) { 2108 if (DEBUG) Log.v(getTag(), "onItemsUpdated positionStart " 2109 + positionStart + " itemCount " + itemCount); 2110 for (int i = positionStart, end = positionStart + itemCount; i < end; i++) { 2111 mChildrenStates.remove(i); 2112 } 2113 } 2114 2115 @Override 2116 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 2117 if (mFocusSearchDisabled) { 2118 return true; 2119 } 2120 if (getPositionByView(child) == NO_POSITION) { 2121 // This shouldn't happen, but in case it does be sure not to attempt a 2122 // scroll to a view whose item has been removed. 2123 return true; 2124 } 2125 if (!mInLayout && !mInSelection) { 2126 scrollToView(child, true); 2127 } 2128 return true; 2129 } 2130 2131 @Override 2132 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 2133 boolean immediate) { 2134 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 2135 return false; 2136 } 2137 2138 int getScrollOffsetX() { 2139 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 2140 } 2141 2142 int getScrollOffsetY() { 2143 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 2144 } 2145 2146 public void getViewSelectedOffsets(View view, int[] offsets) { 2147 if (mOrientation == HORIZONTAL) { 2148 offsets[0] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2149 offsets[1] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2150 } else { 2151 offsets[1] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 2152 offsets[0] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 2153 } 2154 } 2155 2156 private int getPrimarySystemScrollPosition(View view) { 2157 final int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 2158 final int viewMin = getViewMin(view); 2159 final int viewMax = getViewMax(view); 2160 // TODO: change to use State object in onRequestChildFocus() 2161 boolean isMin, isMax; 2162 if (!mReverseFlowPrimary) { 2163 isMin = mGrid.getFirstVisibleIndex() == 0; 2164 isMax = mGrid.getLastVisibleIndex() == (mState == null ? 2165 getItemCount() : mState.getItemCount()) - 1; 2166 } else { 2167 isMax = mGrid.getFirstVisibleIndex() == 0; 2168 isMin = mGrid.getLastVisibleIndex() == (mState == null ? 2169 getItemCount() : mState.getItemCount()) - 1; 2170 } 2171 for (int i = getChildCount() - 1; (isMin || isMax) && i >= 0; i--) { 2172 View v = getChildAt(i); 2173 if (v == view || v == null) { 2174 continue; 2175 } 2176 if (isMin && getViewMin(v) < viewMin) { 2177 isMin = false; 2178 } 2179 if (isMax && getViewMax(v) > viewMax) { 2180 isMax = false; 2181 } 2182 } 2183 return mWindowAlignment.mainAxis().getSystemScrollPos(viewCenterPrimary, isMin, isMax); 2184 } 2185 2186 private int getSecondarySystemScrollPosition(View view) { 2187 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 2188 int pos = getPositionByView(view); 2189 Grid.Location location = mGrid.getLocation(pos); 2190 final int row = location.row; 2191 final boolean isMin, isMax; 2192 if (!mReverseFlowSecondary) { 2193 isMin = row == 0; 2194 isMax = row == mGrid.getNumRows() - 1; 2195 } else { 2196 isMax = row == 0; 2197 isMin = row == mGrid.getNumRows() - 1; 2198 } 2199 return mWindowAlignment.secondAxis().getSystemScrollPos(viewCenterSecondary, isMin, isMax); 2200 } 2201 2202 /** 2203 * Scroll to a given child view and change mFocusPosition. 2204 */ 2205 private void scrollToView(View view, boolean smooth) { 2206 int newFocusPosition = getPositionByView(view); 2207 if (newFocusPosition != mFocusPosition) { 2208 mFocusPosition = newFocusPosition; 2209 mFocusPositionOffset = 0; 2210 if (!mInLayout) { 2211 dispatchChildSelected(); 2212 } 2213 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 2214 mBaseGridView.invalidate(); 2215 } 2216 } 2217 if (view == null) { 2218 return; 2219 } 2220 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 2221 // transfer focus to the child if it does not have focus yet (e.g. triggered 2222 // by setSelection()) 2223 view.requestFocus(); 2224 } 2225 if (!mScrollEnabled && smooth) { 2226 return; 2227 } 2228 if (getScrollPosition(view, sTwoInts)) { 2229 scrollGrid(sTwoInts[0], sTwoInts[1], smooth); 2230 } 2231 } 2232 2233 private boolean getScrollPosition(View view, int[] deltas) { 2234 switch (mFocusScrollStrategy) { 2235 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2236 default: 2237 return getAlignedPosition(view, deltas); 2238 case BaseGridView.FOCUS_SCROLL_ITEM: 2239 case BaseGridView.FOCUS_SCROLL_PAGE: 2240 return getNoneAlignedPosition(view, deltas); 2241 } 2242 } 2243 2244 private boolean getNoneAlignedPosition(View view, int[] deltas) { 2245 int pos = getPositionByView(view); 2246 int viewMin = getViewMin(view); 2247 int viewMax = getViewMax(view); 2248 // we either align "firstView" to left/top padding edge 2249 // or align "lastView" to right/bottom padding edge 2250 View firstView = null; 2251 View lastView = null; 2252 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 2253 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 2254 final int row = mGrid.getRowIndex(pos); 2255 if (viewMin < paddingLow) { 2256 // view enters low padding area: 2257 firstView = view; 2258 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2259 // scroll one "page" left/top, 2260 // align first visible item of the "page" at the low padding edge. 2261 while (prependOneColumnVisibleItems()) { 2262 CircularIntArray positions = 2263 mGrid.getItemPositionsInRows(mGrid.getFirstVisibleIndex(), pos)[row]; 2264 firstView = findViewByPosition(positions.get(0)); 2265 if (viewMax - getViewMin(firstView) > clientSize) { 2266 if (positions.size() > 2) { 2267 firstView = findViewByPosition(positions.get(2)); 2268 } 2269 break; 2270 } 2271 } 2272 } 2273 } else if (viewMax > clientSize + paddingLow) { 2274 // view enters high padding area: 2275 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2276 // scroll whole one page right/bottom, align view at the low padding edge. 2277 firstView = view; 2278 do { 2279 CircularIntArray positions = 2280 mGrid.getItemPositionsInRows(pos, mGrid.getLastVisibleIndex())[row]; 2281 lastView = findViewByPosition(positions.get(positions.size() - 1)); 2282 if (getViewMax(lastView) - viewMin > clientSize) { 2283 lastView = null; 2284 break; 2285 } 2286 } while (appendOneColumnVisibleItems()); 2287 if (lastView != null) { 2288 // however if we reached end, we should align last view. 2289 firstView = null; 2290 } 2291 } else { 2292 lastView = view; 2293 } 2294 } 2295 int scrollPrimary = 0; 2296 int scrollSecondary = 0; 2297 if (firstView != null) { 2298 scrollPrimary = getViewMin(firstView) - paddingLow; 2299 } else if (lastView != null) { 2300 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 2301 } 2302 View secondaryAlignedView; 2303 if (firstView != null) { 2304 secondaryAlignedView = firstView; 2305 } else if (lastView != null) { 2306 secondaryAlignedView = lastView; 2307 } else { 2308 secondaryAlignedView = view; 2309 } 2310 scrollSecondary = getSecondarySystemScrollPosition(secondaryAlignedView); 2311 scrollSecondary -= mScrollOffsetSecondary; 2312 if (scrollPrimary != 0 || scrollSecondary != 0) { 2313 deltas[0] = scrollPrimary; 2314 deltas[1] = scrollSecondary; 2315 return true; 2316 } 2317 return false; 2318 } 2319 2320 private boolean getAlignedPosition(View view, int[] deltas) { 2321 int scrollPrimary = getPrimarySystemScrollPosition(view); 2322 int scrollSecondary = getSecondarySystemScrollPosition(view); 2323 if (DEBUG) { 2324 Log.v(getTag(), "getAlignedPosition " + scrollPrimary + " " + scrollSecondary 2325 + " " + mWindowAlignment); 2326 Log.v(getTag(), "getAlignedPosition " + mScrollOffsetPrimary + " " + mScrollOffsetSecondary); 2327 } 2328 scrollPrimary -= mScrollOffsetPrimary; 2329 scrollSecondary -= mScrollOffsetSecondary; 2330 if (scrollPrimary != 0 || scrollSecondary != 0) { 2331 deltas[0] = scrollPrimary; 2332 deltas[1] = scrollSecondary; 2333 return true; 2334 } 2335 return false; 2336 } 2337 2338 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 2339 if (mInLayout) { 2340 scrollDirectionPrimary(scrollPrimary); 2341 scrollDirectionSecondary(scrollSecondary); 2342 } else { 2343 int scrollX; 2344 int scrollY; 2345 if (mOrientation == HORIZONTAL) { 2346 scrollX = scrollPrimary; 2347 scrollY = scrollSecondary; 2348 } else { 2349 scrollX = scrollSecondary; 2350 scrollY = scrollPrimary; 2351 } 2352 if (smooth) { 2353 mBaseGridView.smoothScrollBy(scrollX, scrollY); 2354 } else { 2355 mBaseGridView.scrollBy(scrollX, scrollY); 2356 } 2357 } 2358 } 2359 2360 public void setPruneChild(boolean pruneChild) { 2361 if (mPruneChild != pruneChild) { 2362 mPruneChild = pruneChild; 2363 if (mPruneChild) { 2364 requestLayout(); 2365 } 2366 } 2367 } 2368 2369 public boolean getPruneChild() { 2370 return mPruneChild; 2371 } 2372 2373 public void setScrollEnabled(boolean scrollEnabled) { 2374 if (mScrollEnabled != scrollEnabled) { 2375 mScrollEnabled = scrollEnabled; 2376 if (mScrollEnabled && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED 2377 && mFocusPosition != NO_POSITION) { 2378 scrollToSelection(mBaseGridView, mFocusPosition, true); 2379 } 2380 } 2381 } 2382 2383 public boolean isScrollEnabled() { 2384 return mScrollEnabled; 2385 } 2386 2387 private int findImmediateChildIndex(View view) { 2388 while (view != null && view != mBaseGridView) { 2389 int index = mBaseGridView.indexOfChild(view); 2390 if (index >= 0) { 2391 return index; 2392 } 2393 view = (View) view.getParent(); 2394 } 2395 return NO_POSITION; 2396 } 2397 2398 void setFocusSearchDisabled(boolean disabled) { 2399 mFocusSearchDisabled = disabled; 2400 } 2401 2402 boolean isFocusSearchDisabled() { 2403 return mFocusSearchDisabled; 2404 } 2405 2406 @Override 2407 public View onInterceptFocusSearch(View focused, int direction) { 2408 if (mFocusSearchDisabled) { 2409 return focused; 2410 } 2411 return null; 2412 } 2413 2414 boolean hasPreviousViewInSameRow(int pos) { 2415 if (mGrid == null || pos == NO_POSITION || mGrid.getFirstVisibleIndex() < 0) { 2416 return false; 2417 } 2418 if (mGrid.getFirstVisibleIndex() > 0) { 2419 return true; 2420 } 2421 final int focusedRow = mGrid.getLocation(pos).row; 2422 for (int i = getChildCount() - 1; i >= 0; i--) { 2423 int position = getPositionByIndex(i); 2424 Grid.Location loc = mGrid.getLocation(position); 2425 if (loc != null && loc.row == focusedRow) { 2426 if (position < pos) { 2427 return true; 2428 } 2429 } 2430 } 2431 return false; 2432 } 2433 2434 @Override 2435 public boolean onAddFocusables(RecyclerView recyclerView, 2436 ArrayList<View> views, int direction, int focusableMode) { 2437 if (mFocusSearchDisabled) { 2438 return true; 2439 } 2440 // If this viewgroup or one of its children currently has focus then we 2441 // consider our children for focus searching in main direction on the same row. 2442 // If this viewgroup has no focus and using focus align, we want the system 2443 // to ignore our children and pass focus to the viewgroup, which will pass 2444 // focus on to its children appropriately. 2445 // If this viewgroup has no focus and not using focus align, we want to 2446 // consider the child that does not overlap with padding area. 2447 if (recyclerView.hasFocus()) { 2448 final int movement = getMovement(direction); 2449 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2450 // Move on secondary direction uses default addFocusables(). 2451 return false; 2452 } 2453 if (mPendingMoveSmoothScroller != null) { 2454 // don't find next focusable if has pending movement. 2455 return true; 2456 } 2457 final View focused = recyclerView.findFocus(); 2458 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2459 // Add focusables of focused item. 2460 if (focusedPos != NO_POSITION) { 2461 findViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2462 } 2463 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2464 mGrid.getLocation(focusedPos).row : NO_POSITION; 2465 // Add focusables of next neighbor of same row on the focus search direction. 2466 if (mGrid != null) { 2467 final int focusableCount = views.size(); 2468 for (int i = 0, count = getChildCount(); i < count; i++) { 2469 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2470 final View child = getChildAt(index); 2471 if (child.getVisibility() != View.VISIBLE || !child.hasFocusable()) { 2472 continue; 2473 } 2474 int position = getPositionByIndex(index); 2475 Grid.Location loc = mGrid.getLocation(position); 2476 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2477 if (focusedPos == NO_POSITION || 2478 (movement == NEXT_ITEM && position > focusedPos) 2479 || (movement == PREV_ITEM && position < focusedPos)) { 2480 child.addFocusables(views, direction, focusableMode); 2481 if (views.size() > focusableCount) { 2482 break; 2483 } 2484 } 2485 } 2486 } 2487 } 2488 } else { 2489 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2490 // adding views not overlapping padding area to avoid scrolling in gaining focus 2491 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2492 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2493 int focusableCount = views.size(); 2494 for (int i = 0, count = getChildCount(); i < count; i++) { 2495 View child = getChildAt(i); 2496 if (child.getVisibility() == View.VISIBLE) { 2497 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2498 child.addFocusables(views, direction, focusableMode); 2499 } 2500 } 2501 } 2502 // if we cannot find any, then just add all children. 2503 if (views.size() == focusableCount) { 2504 for (int i = 0, count = getChildCount(); i < count; i++) { 2505 View child = getChildAt(i); 2506 if (child.getVisibility() == View.VISIBLE) { 2507 child.addFocusables(views, direction, focusableMode); 2508 } 2509 } 2510 if (views.size() != focusableCount) { 2511 return true; 2512 } 2513 } else { 2514 return true; 2515 } 2516 // if still cannot find any, fall through and add itself 2517 } 2518 if (recyclerView.isFocusable()) { 2519 views.add(recyclerView); 2520 } 2521 } 2522 return true; 2523 } 2524 2525 private boolean hasCreatedLastItem() { 2526 int count = mState.getItemCount(); 2527 return count == 0 || findViewByPosition(count - 1) != null; 2528 } 2529 2530 private boolean hasCreatedFirstItem() { 2531 int count = mState.getItemCount(); 2532 return count == 0 || findViewByPosition(0) != null; 2533 } 2534 2535 boolean canScrollTo(View view) { 2536 return view.getVisibility() == View.VISIBLE && (!hasFocus() || view.hasFocusable()); 2537 } 2538 2539 @Override 2540 public View onFocusSearchFailed(View focused, int direction, Recycler recycler, 2541 RecyclerView.State state) { 2542 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2543 2544 View view = null; 2545 int movement = getMovement(direction); 2546 final boolean isScroll = mBaseGridView.getScrollState() != RecyclerView.SCROLL_STATE_IDLE; 2547 saveContext(recycler, state); 2548 if (movement == NEXT_ITEM) { 2549 if (isScroll || !mFocusOutEnd) { 2550 view = focused; 2551 } 2552 if (mScrollEnabled && !hasCreatedLastItem()) { 2553 processPendingMovement(true); 2554 view = focused; 2555 } 2556 } else if (movement == PREV_ITEM) { 2557 if (isScroll || !mFocusOutFront) { 2558 view = focused; 2559 } 2560 if (mScrollEnabled && !hasCreatedFirstItem()) { 2561 processPendingMovement(false); 2562 view = focused; 2563 } 2564 } 2565 leaveContext(); 2566 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed returning view " + view); 2567 return view; 2568 } 2569 2570 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2571 Rect previouslyFocusedRect) { 2572 switch (mFocusScrollStrategy) { 2573 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2574 default: 2575 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2576 direction, previouslyFocusedRect); 2577 case BaseGridView.FOCUS_SCROLL_PAGE: 2578 case BaseGridView.FOCUS_SCROLL_ITEM: 2579 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2580 direction, previouslyFocusedRect); 2581 } 2582 } 2583 2584 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2585 int direction, Rect previouslyFocusedRect) { 2586 View view = findViewByPosition(mFocusPosition); 2587 if (view != null) { 2588 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2589 if (!result && DEBUG) { 2590 Log.w(getTag(), "failed to request focus on " + view); 2591 } 2592 return result; 2593 } 2594 return false; 2595 } 2596 2597 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2598 int direction, Rect previouslyFocusedRect) { 2599 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2600 int index; 2601 int increment; 2602 int end; 2603 int count = getChildCount(); 2604 if ((direction & View.FOCUS_FORWARD) != 0) { 2605 index = 0; 2606 increment = 1; 2607 end = count; 2608 } else { 2609 index = count - 1; 2610 increment = -1; 2611 end = -1; 2612 } 2613 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2614 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2615 for (int i = index; i != end; i += increment) { 2616 View child = getChildAt(i); 2617 if (child.getVisibility() == View.VISIBLE) { 2618 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2619 if (child.requestFocus(direction, previouslyFocusedRect)) { 2620 return true; 2621 } 2622 } 2623 } 2624 } 2625 return false; 2626 } 2627 2628 private final static int PREV_ITEM = 0; 2629 private final static int NEXT_ITEM = 1; 2630 private final static int PREV_ROW = 2; 2631 private final static int NEXT_ROW = 3; 2632 2633 private int getMovement(int direction) { 2634 int movement = View.FOCUS_LEFT; 2635 2636 if (mOrientation == HORIZONTAL) { 2637 switch(direction) { 2638 case View.FOCUS_LEFT: 2639 movement = (!mReverseFlowPrimary) ? PREV_ITEM : NEXT_ITEM; 2640 break; 2641 case View.FOCUS_RIGHT: 2642 movement = (!mReverseFlowPrimary) ? NEXT_ITEM : PREV_ITEM; 2643 break; 2644 case View.FOCUS_UP: 2645 movement = PREV_ROW; 2646 break; 2647 case View.FOCUS_DOWN: 2648 movement = NEXT_ROW; 2649 break; 2650 } 2651 } else if (mOrientation == VERTICAL) { 2652 switch(direction) { 2653 case View.FOCUS_LEFT: 2654 movement = (!mReverseFlowPrimary) ? PREV_ROW : NEXT_ROW; 2655 break; 2656 case View.FOCUS_RIGHT: 2657 movement = (!mReverseFlowPrimary) ? NEXT_ROW : PREV_ROW; 2658 break; 2659 case View.FOCUS_UP: 2660 movement = PREV_ITEM; 2661 break; 2662 case View.FOCUS_DOWN: 2663 movement = NEXT_ITEM; 2664 break; 2665 } 2666 } 2667 2668 return movement; 2669 } 2670 2671 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2672 View view = findViewByPosition(mFocusPosition); 2673 if (view == null) { 2674 return i; 2675 } 2676 int focusIndex = recyclerView.indexOfChild(view); 2677 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2678 // drawing order is 0 1 2 3 9 8 7 6 5 4 2679 if (i < focusIndex) { 2680 return i; 2681 } else if (i < childCount - 1) { 2682 return focusIndex + childCount - 1 - i; 2683 } else { 2684 return focusIndex; 2685 } 2686 } 2687 2688 @Override 2689 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2690 RecyclerView.Adapter newAdapter) { 2691 if (DEBUG) Log.v(getTag(), "onAdapterChanged to " + newAdapter); 2692 if (oldAdapter != null) { 2693 discardLayoutInfo(); 2694 mFocusPosition = NO_POSITION; 2695 mFocusPositionOffset = 0; 2696 mChildrenStates.clear(); 2697 } 2698 super.onAdapterChanged(oldAdapter, newAdapter); 2699 } 2700 2701 private void discardLayoutInfo() { 2702 mGrid = null; 2703 mRowSizeSecondary = null; 2704 mRowSecondarySizeRefresh = false; 2705 } 2706 2707 public void setLayoutEnabled(boolean layoutEnabled) { 2708 if (mLayoutEnabled != layoutEnabled) { 2709 mLayoutEnabled = layoutEnabled; 2710 requestLayout(); 2711 } 2712 } 2713 2714 void setChildrenVisibility(int visiblity) { 2715 mChildVisibility = visiblity; 2716 if (mChildVisibility != -1) { 2717 int count = getChildCount(); 2718 for (int i= 0; i < count; i++) { 2719 getChildAt(i).setVisibility(mChildVisibility); 2720 } 2721 } 2722 } 2723 2724 final static class SavedState implements Parcelable { 2725 2726 int index; // index inside adapter of the current view 2727 Bundle childStates = Bundle.EMPTY; 2728 2729 @Override 2730 public void writeToParcel(Parcel out, int flags) { 2731 out.writeInt(index); 2732 out.writeBundle(childStates); 2733 } 2734 2735 @SuppressWarnings("hiding") 2736 public static final Parcelable.Creator<SavedState> CREATOR = 2737 new Parcelable.Creator<SavedState>() { 2738 @Override 2739 public SavedState createFromParcel(Parcel in) { 2740 return new SavedState(in); 2741 } 2742 2743 @Override 2744 public SavedState[] newArray(int size) { 2745 return new SavedState[size]; 2746 } 2747 }; 2748 2749 @Override 2750 public int describeContents() { 2751 return 0; 2752 } 2753 2754 SavedState(Parcel in) { 2755 index = in.readInt(); 2756 childStates = in.readBundle(GridLayoutManager.class.getClassLoader()); 2757 } 2758 2759 SavedState() { 2760 } 2761 } 2762 2763 @Override 2764 public Parcelable onSaveInstanceState() { 2765 if (DEBUG) Log.v(getTag(), "onSaveInstanceState getSelection() " + getSelection()); 2766 SavedState ss = new SavedState(); 2767 for (int i = 0, count = getChildCount(); i < count; i++) { 2768 View view = getChildAt(i); 2769 int position = getPositionByView(view); 2770 if (position != NO_POSITION) { 2771 mChildrenStates.saveOnScreenView(view, position); 2772 } 2773 } 2774 ss.index = getSelection(); 2775 ss.childStates = mChildrenStates.saveAsBundle(); 2776 return ss; 2777 } 2778 2779 void onChildRecycled(RecyclerView.ViewHolder holder) { 2780 final int position = holder.getAdapterPosition(); 2781 if (position != NO_POSITION) { 2782 mChildrenStates.saveOffscreenView(holder.itemView, position); 2783 } 2784 } 2785 2786 @Override 2787 public void onRestoreInstanceState(Parcelable state) { 2788 if (!(state instanceof SavedState)) { 2789 return; 2790 } 2791 SavedState loadingState = (SavedState)state; 2792 mFocusPosition = loadingState.index; 2793 mFocusPositionOffset = 0; 2794 mChildrenStates.loadFromBundle(loadingState.childStates); 2795 mForceFullLayout = true; 2796 requestLayout(); 2797 if (DEBUG) Log.v(getTag(), "onRestoreInstanceState mFocusPosition " + mFocusPosition); 2798 } 2799} 2800