GridLayoutManager.java revision 92a959ab2b3c3c99aabb03cd999ff223763128da
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.animation.TimeAnimator; 17import android.content.Context; 18import android.graphics.PointF; 19import android.graphics.Rect; 20import android.support.v7.widget.LinearSmoothScroller; 21import android.support.v7.widget.RecyclerView; 22import android.support.v7.widget.RecyclerView.Recycler; 23import android.support.v7.widget.RecyclerView.State; 24 25import static android.support.v7.widget.RecyclerView.NO_ID; 26import static android.support.v7.widget.RecyclerView.NO_POSITION; 27import static android.support.v7.widget.RecyclerView.HORIZONTAL; 28import static android.support.v7.widget.RecyclerView.VERTICAL; 29 30import android.util.AttributeSet; 31import android.util.Log; 32import android.view.FocusFinder; 33import android.view.Gravity; 34import android.view.View; 35import android.view.ViewParent; 36import android.view.View.MeasureSpec; 37import android.view.ViewGroup.MarginLayoutParams; 38import android.view.ViewGroup; 39import android.view.animation.DecelerateInterpolator; 40import android.view.animation.Interpolator; 41 42import java.io.PrintWriter; 43import java.io.StringWriter; 44import java.util.ArrayList; 45import java.util.List; 46 47final class GridLayoutManager extends RecyclerView.LayoutManager { 48 49 /* 50 * LayoutParams for {@link HorizontalGridView} and {@link VerticalGridView}. 51 * The class currently does two internal jobs: 52 * - Saves optical bounds insets. 53 * - Caches focus align view center. 54 */ 55 static class LayoutParams extends RecyclerView.LayoutParams { 56 57 // The view is saved only during animation. 58 private View mView; 59 60 // For placement 61 private int mLeftInset; 62 private int mTopInset; 63 private int mRighInset; 64 private int mBottomInset; 65 66 // For alignment 67 private int mAlignX; 68 private int mAlignY; 69 70 public LayoutParams(Context c, AttributeSet attrs) { 71 super(c, attrs); 72 } 73 74 public LayoutParams(int width, int height) { 75 super(width, height); 76 } 77 78 public LayoutParams(MarginLayoutParams source) { 79 super(source); 80 } 81 82 public LayoutParams(ViewGroup.LayoutParams source) { 83 super(source); 84 } 85 86 public LayoutParams(RecyclerView.LayoutParams source) { 87 super(source); 88 } 89 90 public LayoutParams(LayoutParams source) { 91 super(source); 92 } 93 94 int getAlignX() { 95 return mAlignX; 96 } 97 98 int getAlignY() { 99 return mAlignY; 100 } 101 102 int getOpticalLeft(View view) { 103 return view.getLeft() + mLeftInset; 104 } 105 106 int getOpticalTop(View view) { 107 return view.getTop() + mTopInset; 108 } 109 110 int getOpticalRight(View view) { 111 return view.getRight() - mRighInset; 112 } 113 114 int getOpticalBottom(View view) { 115 return view.getBottom() - mBottomInset; 116 } 117 118 int getOpticalWidth(View view) { 119 return view.getWidth() - mLeftInset - mRighInset; 120 } 121 122 int getOpticalHeight(View view) { 123 return view.getHeight() - mTopInset - mBottomInset; 124 } 125 126 int getOpticalLeftInset() { 127 return mLeftInset; 128 } 129 130 int getOpticalRightInset() { 131 return mRighInset; 132 } 133 134 int getOpticalTopInset() { 135 return mTopInset; 136 } 137 138 int getOpticalBottomInset() { 139 return mBottomInset; 140 } 141 142 void setAlignX(int alignX) { 143 mAlignX = alignX; 144 } 145 146 void setAlignY(int alignY) { 147 mAlignY = alignY; 148 } 149 150 void setOpticalInsets(int leftInset, int topInset, int rightInset, int bottomInset) { 151 mLeftInset = leftInset; 152 mTopInset = topInset; 153 mRighInset = rightInset; 154 mBottomInset = bottomInset; 155 } 156 157 private void invalidateItemDecoration() { 158 ViewParent parent = mView.getParent(); 159 if (parent instanceof RecyclerView) { 160 // TODO: we only need invalidate parent if it has ItemDecoration 161 ((RecyclerView) parent).invalidate(); 162 } 163 } 164 } 165 166 private static final String TAG = "GridLayoutManager"; 167 private static final boolean DEBUG = false; 168 169 private static final Interpolator sDefaultAnimationChildLayoutInterpolator 170 = new DecelerateInterpolator(); 171 172 private static final long DEFAULT_CHILD_ANIMATION_DURATION_MS = 250; 173 174 private String getTag() { 175 return TAG + ":" + mBaseGridView.getId(); 176 } 177 178 private final BaseGridView mBaseGridView; 179 180 /** 181 * The orientation of a "row". 182 */ 183 private int mOrientation = HORIZONTAL; 184 185 private RecyclerView.State mState; 186 private RecyclerView.Recycler mRecycler; 187 188 private boolean mInLayout = false; 189 190 private OnChildSelectedListener mChildSelectedListener = null; 191 192 /** 193 * The focused position, it's not the currently visually aligned position 194 * but it is the final position that we intend to focus on. If there are 195 * multiple setSelection() called, mFocusPosition saves last value. 196 */ 197 private int mFocusPosition = NO_POSITION; 198 199 /** 200 * Force a full layout under certain situations. 201 */ 202 private boolean mForceFullLayout; 203 204 /** 205 * True if layout is enabled. 206 */ 207 private boolean mLayoutEnabled = true; 208 209 /** 210 * The scroll offsets of the viewport relative to the entire view. 211 */ 212 private int mScrollOffsetPrimary; 213 private int mScrollOffsetSecondary; 214 215 /** 216 * User-specified row height/column width. Can be WRAP_CONTENT. 217 */ 218 private int mRowSizeSecondaryRequested; 219 220 /** 221 * The fixed size of each grid item in the secondary direction. This corresponds to 222 * the row height, equal for all rows. Grid items may have variable length 223 * in the primary direction. 224 */ 225 private int mFixedRowSizeSecondary; 226 227 /** 228 * Tracks the secondary size of each row. 229 */ 230 private int[] mRowSizeSecondary; 231 232 /** 233 * Flag controlling whether the current/next layout should 234 * be updating the secondary size of rows. 235 */ 236 private boolean mRowSecondarySizeRefresh; 237 238 /** 239 * The maximum measured size of the view. 240 */ 241 private int mMaxSizeSecondary; 242 243 /** 244 * Margin between items. 245 */ 246 private int mHorizontalMargin; 247 /** 248 * Margin between items vertically. 249 */ 250 private int mVerticalMargin; 251 /** 252 * Margin in main direction. 253 */ 254 private int mMarginPrimary; 255 /** 256 * Margin in second direction. 257 */ 258 private int mMarginSecondary; 259 /** 260 * How to position child in secondary direction. 261 */ 262 private int mGravity = Gravity.LEFT | Gravity.TOP; 263 /** 264 * The number of rows in the grid. 265 */ 266 private int mNumRows; 267 /** 268 * Number of rows requested, can be 0 to be determined by parent size and 269 * rowHeight. 270 */ 271 private int mNumRowsRequested = 1; 272 273 /** 274 * Tracking start/end position of each row for visible items. 275 */ 276 private StaggeredGrid.Row[] mRows; 277 278 /** 279 * Saves grid information of each view. 280 */ 281 private StaggeredGrid mGrid; 282 /** 283 * Position of first item (included) that has attached views. 284 */ 285 private int mFirstVisiblePos; 286 /** 287 * Position of last item (included) that has attached views. 288 */ 289 private int mLastVisiblePos; 290 291 /** 292 * Focus Scroll strategy. 293 */ 294 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 295 /** 296 * Defines how item view is aligned in the window. 297 */ 298 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 299 300 /** 301 * Defines how item view is aligned. 302 */ 303 private final ItemAlignment mItemAlignment = new ItemAlignment(); 304 305 /** 306 * Dimensions of the view, width or height depending on orientation. 307 */ 308 private int mSizePrimary; 309 310 /** 311 * Allow DPAD key to navigate out at the front of the View (where position = 0), 312 * default is false. 313 */ 314 private boolean mFocusOutFront; 315 316 /** 317 * Allow DPAD key to navigate out at the end of the view, default is false. 318 */ 319 private boolean mFocusOutEnd; 320 321 /** 322 * True if focus search is disabled. 323 */ 324 private boolean mFocusSearchDisabled; 325 326 /** 327 * Animate layout changes from a child resizing or adding/removing a child. 328 */ 329 private boolean mAnimateChildLayout = true; 330 331 /** 332 * True if prune child, might be disabled during transition. 333 */ 334 private boolean mPruneChild = true; 335 336 private int[] mTempDeltas = new int[2]; 337 338 private boolean mUseDeltaInPreLayout; 339 340 private int mDeltaInPreLayout, mDeltaSecondaryInPreLayout; 341 342 /** 343 * Temporaries used for measuring. 344 */ 345 private int[] mMeasuredDimension = new int[2]; 346 347 public GridLayoutManager(BaseGridView baseGridView) { 348 mBaseGridView = baseGridView; 349 } 350 351 public void setOrientation(int orientation) { 352 if (orientation != HORIZONTAL && orientation != VERTICAL) { 353 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 354 return; 355 } 356 357 mOrientation = orientation; 358 mWindowAlignment.setOrientation(orientation); 359 mItemAlignment.setOrientation(orientation); 360 mForceFullLayout = true; 361 } 362 363 public int getFocusScrollStrategy() { 364 return mFocusScrollStrategy; 365 } 366 367 public void setFocusScrollStrategy(int focusScrollStrategy) { 368 mFocusScrollStrategy = focusScrollStrategy; 369 } 370 371 public void setWindowAlignment(int windowAlignment) { 372 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 373 } 374 375 public int getWindowAlignment() { 376 return mWindowAlignment.mainAxis().getWindowAlignment(); 377 } 378 379 public void setWindowAlignmentOffset(int alignmentOffset) { 380 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 381 } 382 383 public int getWindowAlignmentOffset() { 384 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 385 } 386 387 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 388 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 389 } 390 391 public float getWindowAlignmentOffsetPercent() { 392 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 393 } 394 395 public void setItemAlignmentOffset(int alignmentOffset) { 396 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 397 updateChildAlignments(); 398 } 399 400 public int getItemAlignmentOffset() { 401 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 402 } 403 404 public void setItemAlignmentOffsetWithPadding(boolean withPadding) { 405 mItemAlignment.mainAxis().setItemAlignmentOffsetWithPadding(withPadding); 406 updateChildAlignments(); 407 } 408 409 public boolean isItemAlignmentOffsetWithPadding() { 410 return mItemAlignment.mainAxis().isItemAlignmentOffsetWithPadding(); 411 } 412 413 public void setItemAlignmentOffsetPercent(float offsetPercent) { 414 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 415 updateChildAlignments(); 416 } 417 418 public float getItemAlignmentOffsetPercent() { 419 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 420 } 421 422 public void setItemAlignmentViewId(int viewId) { 423 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 424 updateChildAlignments(); 425 } 426 427 public int getItemAlignmentViewId() { 428 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 429 } 430 431 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 432 mFocusOutFront = throughFront; 433 mFocusOutEnd = throughEnd; 434 } 435 436 public void setNumRows(int numRows) { 437 if (numRows < 0) throw new IllegalArgumentException(); 438 mNumRowsRequested = numRows; 439 mForceFullLayout = true; 440 } 441 442 /** 443 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 444 */ 445 public void setRowHeight(int height) { 446 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 447 mRowSizeSecondaryRequested = height; 448 } else { 449 throw new IllegalArgumentException("Invalid row height: " + height); 450 } 451 } 452 453 public void setItemMargin(int margin) { 454 mVerticalMargin = mHorizontalMargin = margin; 455 mMarginPrimary = mMarginSecondary = margin; 456 } 457 458 public void setVerticalMargin(int margin) { 459 if (mOrientation == HORIZONTAL) { 460 mMarginSecondary = mVerticalMargin = margin; 461 } else { 462 mMarginPrimary = mVerticalMargin = margin; 463 } 464 } 465 466 public void setHorizontalMargin(int margin) { 467 if (mOrientation == HORIZONTAL) { 468 mMarginPrimary = mHorizontalMargin = margin; 469 } else { 470 mMarginSecondary = mHorizontalMargin = margin; 471 } 472 } 473 474 public int getVerticalMargin() { 475 return mVerticalMargin; 476 } 477 478 public int getHorizontalMargin() { 479 return mHorizontalMargin; 480 } 481 482 public void setGravity(int gravity) { 483 mGravity = gravity; 484 } 485 486 protected boolean hasDoneFirstLayout() { 487 return mGrid != null; 488 } 489 490 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 491 mChildSelectedListener = listener; 492 } 493 494 private int getPositionByView(View view) { 495 if (view == null) { 496 return NO_POSITION; 497 } 498 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(view); 499 if (vh == null) { 500 return NO_POSITION; 501 } 502 return vh.getPosition(); 503 } 504 505 private int getPositionByIndex(int index) { 506 return getPositionByView(getChildAt(index)); 507 } 508 509 private void dispatchChildSelected() { 510 if (mChildSelectedListener == null) { 511 return; 512 } 513 if (mFocusPosition != NO_POSITION) { 514 View view = findViewByPosition(mFocusPosition); 515 if (view != null) { 516 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(view); 517 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 518 vh == null? NO_ID: vh.getItemId()); 519 return; 520 } 521 } 522 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 523 } 524 525 @Override 526 public boolean canScrollHorizontally() { 527 // We can scroll horizontally if we have horizontal orientation, or if 528 // we are vertical and have more than one column. 529 return mOrientation == HORIZONTAL || mNumRows > 1; 530 } 531 532 @Override 533 public boolean canScrollVertically() { 534 // We can scroll vertically if we have vertical orientation, or if we 535 // are horizontal and have more than one row. 536 return mOrientation == VERTICAL || mNumRows > 1; 537 } 538 539 @Override 540 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 541 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 542 ViewGroup.LayoutParams.WRAP_CONTENT); 543 } 544 545 @Override 546 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 547 return new LayoutParams(context, attrs); 548 } 549 550 @Override 551 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 552 if (lp instanceof LayoutParams) { 553 return new LayoutParams((LayoutParams) lp); 554 } else if (lp instanceof RecyclerView.LayoutParams) { 555 return new LayoutParams((RecyclerView.LayoutParams) lp); 556 } else if (lp instanceof MarginLayoutParams) { 557 return new LayoutParams((MarginLayoutParams) lp); 558 } else { 559 return new LayoutParams(lp); 560 } 561 } 562 563 protected View getViewForPosition(int position) { 564 return mRecycler.getViewForPosition(position); 565 } 566 567 final int getOpticalLeft(View v) { 568 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 569 } 570 571 final int getOpticalRight(View v) { 572 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 573 } 574 575 final int getOpticalTop(View v) { 576 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 577 } 578 579 final int getOpticalBottom(View v) { 580 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 581 } 582 583 private int getViewMin(View v) { 584 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 585 } 586 587 private int getViewMax(View v) { 588 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 589 } 590 591 private int getViewCenter(View view) { 592 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 593 } 594 595 private int getViewCenterSecondary(View view) { 596 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 597 } 598 599 private int getViewCenterX(View v) { 600 LayoutParams p = (LayoutParams) v.getLayoutParams(); 601 return p.getOpticalLeft(v) + p.getAlignX(); 602 } 603 604 private int getViewCenterY(View v) { 605 LayoutParams p = (LayoutParams) v.getLayoutParams(); 606 return p.getOpticalTop(v) + p.getAlignY(); 607 } 608 609 /** 610 * Save Recycler and State for convenience. Must be paired with leaveContext(). 611 */ 612 private void saveContext(Recycler recycler, State state) { 613 if (mRecycler != null || mState != null) { 614 Log.e(TAG, "Recycler information was not released, bug!"); 615 } 616 mRecycler = recycler; 617 mState = state; 618 } 619 620 /** 621 * Discard saved Recycler and State. 622 */ 623 private void leaveContext() { 624 mRecycler = null; 625 mState = null; 626 } 627 628 /** 629 * Re-initialize data structures for a data change or handling invisible 630 * selection. The method tries its best to preserve position information so 631 * that staggered grid looks same before and after re-initialize. 632 * @param focusPosition The initial focusPosition that we would like to 633 * focus on. 634 * @return Actual position that can be focused on. 635 */ 636 private int init(int focusPosition) { 637 638 final int newItemCount = mState.getItemCount(); 639 640 if (focusPosition == NO_POSITION && newItemCount > 0) { 641 // if focus position is never set before, initialize it to 0 642 focusPosition = 0; 643 } 644 // If adapter has changed then caches are invalid; otherwise, 645 // we try to maintain each row's position if number of rows keeps the same 646 // and existing mGrid contains the focusPosition. 647 if (mRows != null && mNumRows == mRows.length && 648 mGrid != null && mGrid.getSize() > 0 && focusPosition >= 0 && 649 focusPosition >= mGrid.getFirstIndex() && 650 focusPosition <= mGrid.getLastIndex()) { 651 // strip mGrid to a subset (like a column) that contains focusPosition 652 mGrid.stripDownTo(focusPosition); 653 // make sure that remaining items do not exceed new adapter size 654 int firstIndex = mGrid.getFirstIndex(); 655 int lastIndex = mGrid.getLastIndex(); 656 if (DEBUG) { 657 Log .v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " + lastIndex); 658 } 659 for (int i = lastIndex; i >=firstIndex; i--) { 660 if (i >= newItemCount) { 661 mGrid.removeLast(); 662 } 663 } 664 if (mGrid.getSize() == 0) { 665 focusPosition = newItemCount - 1; 666 // initialize row start locations 667 for (int i = 0; i < mNumRows; i++) { 668 mRows[i].low = 0; 669 mRows[i].high = 0; 670 } 671 if (DEBUG) Log.v(getTag(), "mGrid zero size"); 672 } else { 673 // initialize row start locations 674 for (int i = 0; i < mNumRows; i++) { 675 mRows[i].low = Integer.MAX_VALUE; 676 mRows[i].high = Integer.MIN_VALUE; 677 } 678 firstIndex = mGrid.getFirstIndex(); 679 lastIndex = mGrid.getLastIndex(); 680 if (focusPosition > lastIndex) { 681 focusPosition = mGrid.getLastIndex(); 682 } 683 if (DEBUG) { 684 Log.v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " 685 + lastIndex + " focusPosition " + focusPosition); 686 } 687 // fill rows with minimal view positions of the subset 688 for (int i = firstIndex; i <= lastIndex; i++) { 689 View v = findViewByPosition(i); 690 if (v == null) { 691 continue; 692 } 693 int row = mGrid.getLocation(i).row; 694 int low = getViewMin(v) + mScrollOffsetPrimary; 695 if (low < mRows[row].low) { 696 mRows[row].low = mRows[row].high = low; 697 } 698 } 699 int firstItemRowPosition = mRows[mGrid.getLocation(firstIndex).row].low; 700 if (firstItemRowPosition == Integer.MAX_VALUE) { 701 firstItemRowPosition = 0; 702 } 703 if (mState.didStructureChange()) { 704 // if there is structure change, the removed item might be in the 705 // subset, so it is meaningless to maintain the low locations. 706 for (int i = 0; i < mNumRows; i++) { 707 mRows[i].low = firstItemRowPosition; 708 mRows[i].high = firstItemRowPosition; 709 } 710 } else { 711 // fill other rows that does not include the subset using first item 712 for (int i = 0; i < mNumRows; i++) { 713 if (mRows[i].low == Integer.MAX_VALUE) { 714 mRows[i].low = mRows[i].high = firstItemRowPosition; 715 } 716 } 717 } 718 } 719 720 // Same adapter, we can reuse any attached views 721 detachAndScrapAttachedViews(mRecycler); 722 723 } else { 724 // otherwise recreate data structure 725 mRows = new StaggeredGrid.Row[mNumRows]; 726 727 for (int i = 0; i < mNumRows; i++) { 728 mRows[i] = new StaggeredGrid.Row(); 729 } 730 mGrid = new StaggeredGridDefault(); 731 if (newItemCount == 0) { 732 focusPosition = NO_POSITION; 733 } else if (focusPosition >= newItemCount) { 734 focusPosition = newItemCount - 1; 735 } 736 737 // Adapter may have changed so remove all attached views permanently 738 removeAndRecycleAllViews(mRecycler); 739 740 mScrollOffsetPrimary = 0; 741 mScrollOffsetSecondary = 0; 742 mWindowAlignment.reset(); 743 } 744 745 mGrid.setProvider(mGridProvider); 746 // mGrid share the same Row array information 747 mGrid.setRows(mRows); 748 mFirstVisiblePos = mLastVisiblePos = NO_POSITION; 749 750 initScrollController(); 751 updateScrollSecondAxis(); 752 753 return focusPosition; 754 } 755 756 private int getRowSizeSecondary(int rowIndex) { 757 if (mFixedRowSizeSecondary != 0) { 758 return mFixedRowSizeSecondary; 759 } 760 if (mRowSizeSecondary == null) { 761 return 0; 762 } 763 return mRowSizeSecondary[rowIndex]; 764 } 765 766 private int getRowStartSecondary(int rowIndex) { 767 int start = 0; 768 for (int i = 0; i < rowIndex; i++) { 769 start += getRowSizeSecondary(i) + mMarginSecondary; 770 } 771 return start; 772 } 773 774 private int getSizeSecondary() { 775 return getRowStartSecondary(mNumRows - 1) + getRowSizeSecondary(mNumRows - 1); 776 } 777 778 private void measureScrapChild(int position, int widthSpec, int heightSpec, 779 int[] measuredDimension) { 780 View view = mRecycler.getViewForPosition(position); 781 if (view != null) { 782 LayoutParams p = (LayoutParams) view.getLayoutParams(); 783 int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, 784 getPaddingLeft() + getPaddingRight(), p.width); 785 int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, 786 getPaddingTop() + getPaddingBottom(), p.height); 787 view.measure(childWidthSpec, childHeightSpec); 788 measuredDimension[0] = view.getMeasuredWidth(); 789 measuredDimension[1] = view.getMeasuredHeight(); 790 mRecycler.recycleView(view); 791 } 792 } 793 794 private boolean processRowSizeSecondary(boolean measure) { 795 if (mFixedRowSizeSecondary != 0) { 796 return false; 797 } 798 799 if (mGrid == null) { 800 if (mState.getItemCount() > 0) { 801 measureScrapChild(mFocusPosition == NO_POSITION ? 0 : mFocusPosition, 802 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 803 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 804 mMeasuredDimension); 805 if (DEBUG) Log.v(TAG, "measured scrap child: " + mMeasuredDimension[0] + 806 " " + mMeasuredDimension[1]); 807 } else { 808 mMeasuredDimension[0] = mMeasuredDimension[1] = 0; 809 } 810 } 811 812 List<Integer>[] rows = mGrid == null ? null : 813 mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 814 boolean changed = false; 815 816 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 817 int rowSize = 0; 818 819 final int rowItemCount = rows == null ? 1 : rows[rowIndex].size(); 820 if (DEBUG) Log.v(getTag(), "processRowSizeSecondary row " + rowIndex + 821 " rowItemCount " + rowItemCount); 822 823 for (int i = 0; i < rowItemCount; i++) { 824 if (rows != null) { 825 final int position = rows[rowIndex].get(i); 826 final View view = findViewByPosition(position); 827 if (measure && view.isLayoutRequested()) { 828 measureChild(view); 829 } 830 // If this view is outside the primary axis bounds, we ignore it. 831 if (getViewMax(view) < 0 || getViewMin(view) > mSizePrimary) { 832 continue; 833 } 834 mMeasuredDimension[0] = view.getWidth(); 835 mMeasuredDimension[1] = view.getHeight(); 836 } 837 final int secondarySize = mOrientation == HORIZONTAL ? 838 mMeasuredDimension[1] : mMeasuredDimension[0]; 839 if (secondarySize > rowSize) { 840 rowSize = secondarySize; 841 } 842 } 843 if (DEBUG) Log.v(getTag(), "row " + rowIndex + " rowItemCount " + rowItemCount + 844 " rowSize " + rowSize); 845 846 if (mRowSizeSecondary[rowIndex] != rowSize) { 847 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 848 ", " + rowSize); 849 850 mRowSizeSecondary[rowIndex] = rowSize; 851 changed = true; 852 } 853 } 854 855 return changed; 856 } 857 858 /** 859 * Checks if we need to update row secondary sizes. 860 */ 861 private void updateRowSecondarySizeRefresh() { 862 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 863 if (mRowSecondarySizeRefresh) { 864 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 865 forceRequestLayout(); 866 } 867 } 868 869 private void forceRequestLayout() { 870 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 871 // RecyclerView prevents us from requesting layout in many cases 872 // (during layout, during scroll, etc.) 873 // For secondary row size wrap_content support we currently need a 874 // second layout pass to update the measured size after having measured 875 // and added child views in layoutChildren. 876 // Force the second layout by posting a delayed runnable. 877 // TODO: investigate allowing a second layout pass, 878 // or move child add/measure logic to the measure phase. 879 mBaseGridView.getHandler().post(new Runnable() { 880 @Override 881 public void run() { 882 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 883 requestLayout(); 884 } 885 }); 886 } 887 888 @Override 889 public void onMeasure(Recycler recycler, State state, int widthSpec, int heightSpec) { 890 saveContext(recycler, state); 891 892 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 893 int measuredSizeSecondary; 894 if (mOrientation == HORIZONTAL) { 895 sizePrimary = MeasureSpec.getSize(widthSpec); 896 sizeSecondary = MeasureSpec.getSize(heightSpec); 897 modeSecondary = MeasureSpec.getMode(heightSpec); 898 paddingSecondary = getPaddingTop() + getPaddingBottom(); 899 } else { 900 sizeSecondary = MeasureSpec.getSize(widthSpec); 901 sizePrimary = MeasureSpec.getSize(heightSpec); 902 modeSecondary = MeasureSpec.getMode(widthSpec); 903 paddingSecondary = getPaddingLeft() + getPaddingRight(); 904 } 905 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 906 " heightSpec " + Integer.toHexString(heightSpec) + 907 " modeSecondary " + Integer.toHexString(modeSecondary) + 908 " sizeSecondary " + sizeSecondary + " " + this); 909 910 mMaxSizeSecondary = sizeSecondary; 911 912 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 913 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 914 mFixedRowSizeSecondary = 0; 915 916 if (mRowSizeSecondary == null || mRowSizeSecondary.length != mNumRows) { 917 mRowSizeSecondary = new int[mNumRows]; 918 } 919 920 // Measure all current children and update cached row heights 921 processRowSizeSecondary(true); 922 923 switch (modeSecondary) { 924 case MeasureSpec.UNSPECIFIED: 925 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 926 break; 927 case MeasureSpec.AT_MOST: 928 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 929 mMaxSizeSecondary); 930 break; 931 case MeasureSpec.EXACTLY: 932 measuredSizeSecondary = mMaxSizeSecondary; 933 break; 934 default: 935 throw new IllegalStateException("wrong spec"); 936 } 937 938 } else { 939 switch (modeSecondary) { 940 case MeasureSpec.UNSPECIFIED: 941 if (mRowSizeSecondaryRequested == 0) { 942 if (mOrientation == HORIZONTAL) { 943 throw new IllegalStateException("Must specify rowHeight or view height"); 944 } else { 945 throw new IllegalStateException("Must specify columnWidth or view width"); 946 } 947 } 948 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 949 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 950 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 951 * (mNumRows - 1) + paddingSecondary; 952 break; 953 case MeasureSpec.AT_MOST: 954 case MeasureSpec.EXACTLY: 955 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 956 mNumRows = 1; 957 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 958 } else if (mNumRowsRequested == 0) { 959 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 960 mNumRows = (sizeSecondary + mMarginSecondary) 961 / (mRowSizeSecondaryRequested + mMarginSecondary); 962 } else if (mRowSizeSecondaryRequested == 0) { 963 mNumRows = mNumRowsRequested; 964 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 965 * (mNumRows - 1)) / mNumRows; 966 } else { 967 mNumRows = mNumRowsRequested; 968 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 969 } 970 measuredSizeSecondary = sizeSecondary; 971 if (modeSecondary == MeasureSpec.AT_MOST) { 972 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 973 * (mNumRows - 1) + paddingSecondary; 974 if (childrenSize < measuredSizeSecondary) { 975 measuredSizeSecondary = childrenSize; 976 } 977 } 978 break; 979 default: 980 throw new IllegalStateException("wrong spec"); 981 } 982 } 983 if (mOrientation == HORIZONTAL) { 984 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 985 } else { 986 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 987 } 988 if (DEBUG) { 989 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 990 " measuredSizeSecondary " + measuredSizeSecondary + 991 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 992 " mNumRows " + mNumRows); 993 } 994 995 leaveContext(); 996 } 997 998 private void measureChild(View child) { 999 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1000 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1001 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1002 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1003 int widthSpec, heightSpec; 1004 1005 if (mOrientation == HORIZONTAL) { 1006 widthSpec = ViewGroup.getChildMeasureSpec( 1007 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1008 0, lp.width); 1009 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1010 } else { 1011 heightSpec = ViewGroup.getChildMeasureSpec( 1012 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1013 0, lp.height); 1014 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1015 } 1016 1017 child.measure(widthSpec, heightSpec); 1018 1019 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1020 " widthSpec " + Integer.toHexString(widthSpec) + 1021 " heightSpec " + Integer.toHexString(heightSpec) + 1022 " measuredWidth " + child.getMeasuredWidth() + 1023 " measuredHeight " + child.getMeasuredHeight()); 1024 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1025 } 1026 1027 private StaggeredGrid.Provider mGridProvider = new StaggeredGrid.Provider() { 1028 1029 @Override 1030 public int getCount() { 1031 return mState.getItemCount(); 1032 } 1033 1034 @Override 1035 public void createItem(int index, int rowIndex, boolean append) { 1036 View v = getViewForPosition(index); 1037 if (mFirstVisiblePos >= 0) { 1038 // when StaggeredGrid append or prepend item, we must guarantee 1039 // that sibling item has created views already. 1040 if (append && index != mLastVisiblePos + 1) { 1041 throw new RuntimeException(); 1042 } else if (!append && index != mFirstVisiblePos - 1) { 1043 throw new RuntimeException(); 1044 } 1045 } 1046 1047 // See recyclerView docs: we don't need re-add scraped view if it was removed. 1048 if (!((RecyclerView.LayoutParams) v.getLayoutParams()).isItemRemoved()) { 1049 if (append) { 1050 addView(v); 1051 } else { 1052 addView(v, 0); 1053 } 1054 measureChild(v); 1055 } 1056 1057 int length = mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1058 int start, end; 1059 if (append) { 1060 start = mRows[rowIndex].high; 1061 if (start != mRows[rowIndex].low) { 1062 // if there are existing item in the row, add margin between 1063 start += mMarginPrimary; 1064 } else { 1065 final int lastRow = mRows.length - 1; 1066 if (lastRow != rowIndex && mRows[lastRow].high != mRows[lastRow].low) { 1067 // if there are existing item in the last row, insert 1068 // the new item after the last item of last row. 1069 start = mRows[lastRow].high + mMarginPrimary; 1070 } 1071 } 1072 end = start + length; 1073 mRows[rowIndex].high = end; 1074 } else { 1075 end = mRows[rowIndex].low; 1076 if (end != mRows[rowIndex].high) { 1077 end -= mMarginPrimary; 1078 } else if (0 != rowIndex && mRows[0].high != mRows[0].low) { 1079 // if there are existing item in the first row, insert 1080 // the new item before the first item of first row. 1081 end = mRows[0].low - mMarginPrimary; 1082 } 1083 start = end - length; 1084 mRows[rowIndex].low = start; 1085 } 1086 if (mFirstVisiblePos < 0) { 1087 mFirstVisiblePos = mLastVisiblePos = index; 1088 } else { 1089 if (append) { 1090 mLastVisiblePos++; 1091 } else { 1092 mFirstVisiblePos--; 1093 } 1094 } 1095 if (DEBUG) Log.v(getTag(), "start " + start + " end " + end); 1096 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1097 layoutChild(rowIndex, v, start - mScrollOffsetPrimary, end - mScrollOffsetPrimary, 1098 startSecondary); 1099 if (DEBUG) { 1100 Log.d(getTag(), "addView " + index + " " + v); 1101 } 1102 updateScrollMin(); 1103 updateScrollMax(); 1104 } 1105 }; 1106 1107 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1108 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1109 : v.getMeasuredWidth(); 1110 if (mFixedRowSizeSecondary > 0) { 1111 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1112 } 1113 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1114 final int horizontalGravity = mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1115 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1116 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1117 // do nothing 1118 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1119 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1120 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1121 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1122 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1123 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1124 } 1125 int left, top, right, bottom; 1126 if (mOrientation == HORIZONTAL) { 1127 left = start; 1128 top = startSecondary; 1129 right = end; 1130 bottom = startSecondary + sizeSecondary; 1131 } else { 1132 top = start; 1133 left = startSecondary; 1134 bottom = end; 1135 right = startSecondary + sizeSecondary; 1136 } 1137 v.layout(left, top, right, bottom); 1138 updateChildOpticalInsets(v, left, top, right, bottom); 1139 updateChildAlignments(v); 1140 } 1141 1142 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1143 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1144 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1145 v.getRight() - right, v.getBottom() - bottom); 1146 } 1147 1148 private void updateChildAlignments(View v) { 1149 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1150 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1151 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1152 } 1153 1154 private void updateChildAlignments() { 1155 for (int i = 0, c = getChildCount(); i < c; i++) { 1156 updateChildAlignments(getChildAt(i)); 1157 } 1158 } 1159 1160 private boolean needsAppendVisibleItem() { 1161 if (mLastVisiblePos < mFocusPosition) { 1162 return true; 1163 } 1164 int right = mScrollOffsetPrimary + mSizePrimary; 1165 for (int i = 0; i < mNumRows; i++) { 1166 if (mRows[i].low == mRows[i].high) { 1167 if (mRows[i].high < right) { 1168 return true; 1169 } 1170 } else if (mRows[i].high < right - mMarginPrimary) { 1171 return true; 1172 } 1173 } 1174 return false; 1175 } 1176 1177 private boolean needsPrependVisibleItem() { 1178 if (mFirstVisiblePos > mFocusPosition) { 1179 return true; 1180 } 1181 for (int i = 0; i < mNumRows; i++) { 1182 if (mRows[i].low == mRows[i].high) { 1183 if (mRows[i].low > mScrollOffsetPrimary) { 1184 return true; 1185 } 1186 } else if (mRows[i].low - mMarginPrimary > mScrollOffsetPrimary) { 1187 return true; 1188 } 1189 } 1190 return false; 1191 } 1192 1193 // Append one column if possible and return true if reach end. 1194 private boolean appendOneVisibleItem() { 1195 while (true) { 1196 if (mLastVisiblePos != NO_POSITION && mLastVisiblePos < mState.getItemCount() -1 && 1197 mLastVisiblePos < mGrid.getLastIndex()) { 1198 // append invisible view of saved location till last row 1199 final int index = mLastVisiblePos + 1; 1200 final int row = mGrid.getLocation(index).row; 1201 mGridProvider.createItem(index, row, true); 1202 if (row == mNumRows - 1) { 1203 return false; 1204 } 1205 } else if ((mLastVisiblePos == NO_POSITION && mState.getItemCount() > 0) || 1206 (mLastVisiblePos != NO_POSITION && 1207 mLastVisiblePos < mState.getItemCount() - 1)) { 1208 mGrid.appendItems(mScrollOffsetPrimary + mSizePrimary); 1209 return false; 1210 } else { 1211 return true; 1212 } 1213 } 1214 } 1215 1216 private void appendVisibleItems() { 1217 while (needsAppendVisibleItem()) { 1218 if (appendOneVisibleItem()) { 1219 break; 1220 } 1221 } 1222 } 1223 1224 // Prepend one column if possible and return true if reach end. 1225 private boolean prependOneVisibleItem() { 1226 while (true) { 1227 if (mFirstVisiblePos > 0) { 1228 if (mFirstVisiblePos > mGrid.getFirstIndex()) { 1229 // prepend invisible view of saved location till first row 1230 final int index = mFirstVisiblePos - 1; 1231 final int row = mGrid.getLocation(index).row; 1232 mGridProvider.createItem(index, row, false); 1233 if (row == 0) { 1234 return false; 1235 } 1236 } else { 1237 mGrid.prependItems(mScrollOffsetPrimary); 1238 return false; 1239 } 1240 } else { 1241 return true; 1242 } 1243 } 1244 } 1245 1246 private void prependVisibleItems() { 1247 while (needsPrependVisibleItem()) { 1248 if (prependOneVisibleItem()) { 1249 break; 1250 } 1251 } 1252 } 1253 1254 private void removeChildAt(int position) { 1255 View v = findViewByPosition(position); 1256 if (v != null) { 1257 if (DEBUG) { 1258 Log.d(getTag(), "removeAndRecycleViewAt " + position); 1259 } 1260 removeAndRecycleView(v, mRecycler); 1261 } 1262 } 1263 1264 private void removeInvisibleViewsAtEnd() { 1265 if (!mPruneChild) { 1266 return; 1267 } 1268 boolean update = false; 1269 while(mLastVisiblePos > mFirstVisiblePos && mLastVisiblePos > mFocusPosition) { 1270 View view = findViewByPosition(mLastVisiblePos); 1271 if (getViewMin(view) > mSizePrimary) { 1272 removeChildAt(mLastVisiblePos); 1273 mLastVisiblePos--; 1274 update = true; 1275 } else { 1276 break; 1277 } 1278 } 1279 if (update) { 1280 updateRowsMinMax(); 1281 } 1282 } 1283 1284 private void removeInvisibleViewsAtFront() { 1285 if (!mPruneChild) { 1286 return; 1287 } 1288 boolean update = false; 1289 while(mLastVisiblePos > mFirstVisiblePos && mFirstVisiblePos < mFocusPosition) { 1290 View view = findViewByPosition(mFirstVisiblePos); 1291 if (getViewMax(view) < 0) { 1292 removeChildAt(mFirstVisiblePos); 1293 mFirstVisiblePos++; 1294 update = true; 1295 } else { 1296 break; 1297 } 1298 } 1299 if (update) { 1300 updateRowsMinMax(); 1301 } 1302 } 1303 1304 private void updateRowsMinMax() { 1305 if (mFirstVisiblePos < 0) { 1306 return; 1307 } 1308 for (int i = 0; i < mNumRows; i++) { 1309 mRows[i].low = Integer.MAX_VALUE; 1310 mRows[i].high = Integer.MIN_VALUE; 1311 } 1312 for (int i = mFirstVisiblePos; i <= mLastVisiblePos; i++) { 1313 View view = findViewByPosition(i); 1314 int row = mGrid.getLocation(i).row; 1315 int low = getViewMin(view) + mScrollOffsetPrimary; 1316 if (low < mRows[row].low) { 1317 mRows[row].low = low; 1318 } 1319 int high = getViewMax(view) + mScrollOffsetPrimary; 1320 if (high > mRows[row].high) { 1321 mRows[row].high = high; 1322 } 1323 } 1324 } 1325 1326 // Fast layout when there is no structure change, adapter change, etc. 1327 protected void fastRelayout() { 1328 initScrollController(); 1329 1330 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 1331 1332 // relayout and repositioning views on each row 1333 for (int i = 0; i < mNumRows; i++) { 1334 List<Integer> row = rows[i]; 1335 final int startSecondary = getRowStartSecondary(i) - mScrollOffsetSecondary; 1336 for (int j = 0, size = row.size(); j < size; j++) { 1337 final int position = row.get(j); 1338 final View view = findViewByPosition(position); 1339 int primaryDelta, start, end; 1340 1341 if (mOrientation == HORIZONTAL) { 1342 final int primarySize = view.getMeasuredWidth(); 1343 if (view.isLayoutRequested()) { 1344 measureChild(view); 1345 } 1346 start = getViewMin(view); 1347 end = start + view.getMeasuredWidth(); 1348 primaryDelta = view.getMeasuredWidth() - primarySize; 1349 if (primaryDelta != 0) { 1350 for (int k = j + 1; k < size; k++) { 1351 findViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1352 } 1353 } 1354 } else { 1355 final int primarySize = view.getMeasuredHeight(); 1356 if (view.isLayoutRequested()) { 1357 measureChild(view); 1358 } 1359 start = getViewMin(view); 1360 end = start + view.getMeasuredHeight(); 1361 primaryDelta = view.getMeasuredHeight() - primarySize; 1362 if (primaryDelta != 0) { 1363 for (int k = j + 1; k < size; k++) { 1364 findViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1365 } 1366 } 1367 } 1368 layoutChild(i, view, start, end, startSecondary); 1369 } 1370 } 1371 1372 updateRowsMinMax(); 1373 appendVisibleItems(); 1374 prependVisibleItems(); 1375 1376 updateRowsMinMax(); 1377 updateScrollMin(); 1378 updateScrollMax(); 1379 updateScrollSecondAxis(); 1380 1381 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1382 View focusView = findViewByPosition(mFocusPosition == NO_POSITION ? 0 : mFocusPosition); 1383 scrollToView(focusView, false); 1384 } 1385 } 1386 1387 @Override 1388 public boolean supportsItemAnimations() { 1389 return mAnimateChildLayout; 1390 } 1391 1392 private void removeAndRecycleAllViews(RecyclerView.Recycler recycler) { 1393 if (DEBUG) Log.v(TAG, "removeAndRecycleAllViews " + getChildCount()); 1394 for (int i = getChildCount() - 1; i >= 0; i--) { 1395 removeAndRecycleViewAt(i, recycler); 1396 } 1397 } 1398 1399 // Lays out items based on the current scroll position 1400 @Override 1401 public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) { 1402 if (DEBUG) { 1403 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1404 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1405 + " inPreLayout " + state.isPreLayout() 1406 + " didStructureChange " + state.didStructureChange() 1407 + " mForceFullLayout " + mForceFullLayout); 1408 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1409 } 1410 1411 if (mNumRows == 0) { 1412 // haven't done measure yet 1413 return; 1414 } 1415 final int itemCount = state.getItemCount(); 1416 if (itemCount < 0) { 1417 return; 1418 } 1419 1420 if (!mLayoutEnabled) { 1421 discardLayoutInfo(); 1422 removeAndRecycleAllViews(recycler); 1423 return; 1424 } 1425 mInLayout = true; 1426 1427 saveContext(recycler, state); 1428 // Track the old focus view so we can adjust our system scroll position 1429 // so that any scroll animations happening now will remain valid. 1430 // We must use same delta in Pre Layout (if prelayout exists) and second layout. 1431 // So we cache the deltas in PreLayout and use it in second layout. 1432 int delta = 0, deltaSecondary = 0; 1433 if (!state.isPreLayout() && mUseDeltaInPreLayout) { 1434 delta = mDeltaInPreLayout; 1435 deltaSecondary = mDeltaSecondaryInPreLayout; 1436 } else { 1437 if (mFocusPosition != NO_POSITION 1438 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1439 View focusView = findViewByPosition(mFocusPosition); 1440 if (focusView != null) { 1441 delta = mWindowAlignment.mainAxis().getSystemScrollPos( 1442 getViewCenter(focusView) + mScrollOffsetPrimary) - mScrollOffsetPrimary; 1443 deltaSecondary = 1444 mWindowAlignment.secondAxis().getSystemScrollPos( 1445 getViewCenterSecondary(focusView) + mScrollOffsetSecondary) 1446 - mScrollOffsetSecondary; 1447 if (mUseDeltaInPreLayout = state.isPreLayout()) { 1448 mDeltaInPreLayout = delta; 1449 mDeltaSecondaryInPreLayout = deltaSecondary; 1450 } 1451 } 1452 } 1453 } 1454 1455 final boolean hasDoneFirstLayout = hasDoneFirstLayout(); 1456 if (!mState.didStructureChange() && !mForceFullLayout && hasDoneFirstLayout) { 1457 fastRelayout(); 1458 } else { 1459 boolean hadFocus = mBaseGridView.hasFocus(); 1460 1461 int newFocusPosition = init(mFocusPosition); 1462 if (DEBUG) { 1463 Log.v(getTag(), "mFocusPosition " + mFocusPosition + " newFocusPosition " 1464 + newFocusPosition); 1465 } 1466 1467 // depending on result of init(), either recreating everything 1468 // or try to reuse the row start positions near mFocusPosition 1469 if (mGrid.getSize() == 0) { 1470 // this is a fresh creating all items, starting from 1471 // mFocusPosition with a estimated row index. 1472 mGrid.setStart(newFocusPosition, StaggeredGrid.START_DEFAULT); 1473 1474 // Can't track the old focus view 1475 delta = deltaSecondary = 0; 1476 1477 } else { 1478 // mGrid remembers Locations for the column that 1479 // contains mFocusePosition and also mRows remembers start 1480 // positions of each row. 1481 // Manually re-create child views for that column 1482 int firstIndex = mGrid.getFirstIndex(); 1483 int lastIndex = mGrid.getLastIndex(); 1484 for (int i = firstIndex; i <= lastIndex; i++) { 1485 mGridProvider.createItem(i, mGrid.getLocation(i).row, true); 1486 } 1487 } 1488 // add visible views at end until reach the end of window 1489 appendVisibleItems(); 1490 // add visible views at front until reach the start of window 1491 prependVisibleItems(); 1492 // multiple rounds: scrollToView of first round may drag first/last child into 1493 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1494 int oldFirstVisible; 1495 int oldLastVisible; 1496 do { 1497 oldFirstVisible = mFirstVisiblePos; 1498 oldLastVisible = mLastVisiblePos; 1499 View focusView = findViewByPosition(newFocusPosition); 1500 // we need force to initialize the child view's position 1501 scrollToView(focusView, false); 1502 if (focusView != null && hadFocus) { 1503 focusView.requestFocus(); 1504 } 1505 appendVisibleItems(); 1506 prependVisibleItems(); 1507 removeInvisibleViewsAtFront(); 1508 removeInvisibleViewsAtEnd(); 1509 } while (mFirstVisiblePos != oldFirstVisible || mLastVisiblePos != oldLastVisible); 1510 } 1511 mForceFullLayout = false; 1512 1513 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1514 scrollDirectionPrimary(-delta); 1515 scrollDirectionSecondary(-deltaSecondary); 1516 } 1517 appendVisibleItems(); 1518 prependVisibleItems(); 1519 removeInvisibleViewsAtFront(); 1520 removeInvisibleViewsAtEnd(); 1521 1522 if (DEBUG) { 1523 StringWriter sw = new StringWriter(); 1524 PrintWriter pw = new PrintWriter(sw); 1525 mGrid.debugPrint(pw); 1526 Log.d(getTag(), sw.toString()); 1527 } 1528 1529 if (mRowSecondarySizeRefresh) { 1530 mRowSecondarySizeRefresh = false; 1531 } else { 1532 updateRowSecondarySizeRefresh(); 1533 } 1534 1535 if (!state.isPreLayout()) { 1536 mUseDeltaInPreLayout = false; 1537 if (!hasDoneFirstLayout) { 1538 dispatchChildSelected(); 1539 } 1540 } 1541 mInLayout = false; 1542 leaveContext(); 1543 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1544 } 1545 1546 private void offsetChildrenSecondary(int increment) { 1547 final int childCount = getChildCount(); 1548 if (mOrientation == HORIZONTAL) { 1549 for (int i = 0; i < childCount; i++) { 1550 getChildAt(i).offsetTopAndBottom(increment); 1551 } 1552 } else { 1553 for (int i = 0; i < childCount; i++) { 1554 getChildAt(i).offsetLeftAndRight(increment); 1555 } 1556 } 1557 mScrollOffsetSecondary -= increment; 1558 } 1559 1560 private void offsetChildrenPrimary(int increment) { 1561 final int childCount = getChildCount(); 1562 if (mOrientation == VERTICAL) { 1563 for (int i = 0; i < childCount; i++) { 1564 getChildAt(i).offsetTopAndBottom(increment); 1565 } 1566 } else { 1567 for (int i = 0; i < childCount; i++) { 1568 getChildAt(i).offsetLeftAndRight(increment); 1569 } 1570 } 1571 mScrollOffsetPrimary -= increment; 1572 } 1573 1574 @Override 1575 public int scrollHorizontallyBy(int dx, Recycler recycler, RecyclerView.State state) { 1576 if (DEBUG) Log.v(getTag(), "scrollHorizontallyBy " + dx); 1577 if (!mLayoutEnabled) { 1578 return 0; 1579 } 1580 saveContext(recycler, state); 1581 int result; 1582 if (mOrientation == HORIZONTAL) { 1583 result = scrollDirectionPrimary(dx); 1584 } else { 1585 result = scrollDirectionSecondary(dx); 1586 } 1587 leaveContext(); 1588 return result; 1589 } 1590 1591 @Override 1592 public int scrollVerticallyBy(int dy, Recycler recycler, RecyclerView.State state) { 1593 if (DEBUG) Log.v(getTag(), "scrollVerticallyBy " + dy); 1594 if (!mLayoutEnabled) { 1595 return 0; 1596 } 1597 saveContext(recycler, state); 1598 int result; 1599 if (mOrientation == VERTICAL) { 1600 result = scrollDirectionPrimary(dy); 1601 } else { 1602 result = scrollDirectionSecondary(dy); 1603 } 1604 leaveContext(); 1605 return result; 1606 } 1607 1608 // scroll in main direction may add/prune views 1609 private int scrollDirectionPrimary(int da) { 1610 if (da == 0) { 1611 return 0; 1612 } 1613 offsetChildrenPrimary(-da); 1614 if (mInLayout) { 1615 return da; 1616 } 1617 1618 int childCount = getChildCount(); 1619 boolean updated; 1620 1621 if (da > 0) { 1622 appendVisibleItems(); 1623 } else if (da < 0) { 1624 prependVisibleItems(); 1625 } 1626 updated = getChildCount() > childCount; 1627 childCount = getChildCount(); 1628 1629 if (da > 0) { 1630 removeInvisibleViewsAtFront(); 1631 } else if (da < 0) { 1632 removeInvisibleViewsAtEnd(); 1633 } 1634 updated |= getChildCount() < childCount; 1635 1636 if (updated) { 1637 updateRowSecondarySizeRefresh(); 1638 } 1639 1640 mBaseGridView.invalidate(); 1641 return da; 1642 } 1643 1644 // scroll in second direction will not add/prune views 1645 private int scrollDirectionSecondary(int dy) { 1646 if (dy == 0) { 1647 return 0; 1648 } 1649 offsetChildrenSecondary(-dy); 1650 mBaseGridView.invalidate(); 1651 return dy; 1652 } 1653 1654 private void updateScrollMax() { 1655 if (mLastVisiblePos >= 0 && mLastVisiblePos == mState.getItemCount() - 1) { 1656 int maxEdge = Integer.MIN_VALUE; 1657 for (int i = 0; i < mRows.length; i++) { 1658 if (mRows[i].high > maxEdge) { 1659 maxEdge = mRows[i].high; 1660 } 1661 } 1662 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1663 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge); 1664 } 1665 } 1666 1667 private void updateScrollMin() { 1668 if (mFirstVisiblePos == 0) { 1669 int minEdge = Integer.MAX_VALUE; 1670 for (int i = 0; i < mRows.length; i++) { 1671 if (mRows[i].low < minEdge) { 1672 minEdge = mRows[i].low; 1673 } 1674 } 1675 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1676 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge); 1677 } 1678 } 1679 1680 private void updateScrollSecondAxis() { 1681 mWindowAlignment.secondAxis().setMinEdge(0); 1682 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1683 } 1684 1685 private void initScrollController() { 1686 mWindowAlignment.horizontal.setSize(getWidth()); 1687 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1688 mWindowAlignment.vertical.setSize(getHeight()); 1689 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1690 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1691 mWindowAlignment.mainAxis().invalidateScrollMin(); 1692 mWindowAlignment.mainAxis().invalidateScrollMax(); 1693 1694 if (DEBUG) { 1695 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1696 + " mWindowAlignment " + mWindowAlignment); 1697 } 1698 } 1699 1700 public void setSelection(RecyclerView parent, int position) { 1701 setSelection(parent, position, false); 1702 } 1703 1704 public void setSelectionSmooth(RecyclerView parent, int position) { 1705 setSelection(parent, position, true); 1706 } 1707 1708 public int getSelection() { 1709 return mFocusPosition; 1710 } 1711 1712 public void setSelection(RecyclerView parent, int position, boolean smooth) { 1713 if (mFocusPosition == position) { 1714 return; 1715 } 1716 View view = findViewByPosition(position); 1717 if (view != null) { 1718 scrollToView(view, smooth); 1719 } else { 1720 mFocusPosition = position; 1721 if (!mLayoutEnabled) { 1722 return; 1723 } 1724 if (smooth) { 1725 if (!hasDoneFirstLayout()) { 1726 Log.w(getTag(), "setSelectionSmooth should " + 1727 "not be called before first layout pass"); 1728 return; 1729 } 1730 LinearSmoothScroller linearSmoothScroller = 1731 new LinearSmoothScroller(parent.getContext()) { 1732 @Override 1733 public PointF computeScrollVectorForPosition(int targetPosition) { 1734 if (getChildCount() == 0) { 1735 return null; 1736 } 1737 final int firstChildPos = getPosition(getChildAt(0)); 1738 final int direction = targetPosition < firstChildPos ? -1 : 1; 1739 if (mOrientation == HORIZONTAL) { 1740 return new PointF(direction, 0); 1741 } else { 1742 return new PointF(0, direction); 1743 } 1744 } 1745 @Override 1746 protected void onTargetFound(View targetView, 1747 RecyclerView.State state, Action action) { 1748 if (hasFocus()) { 1749 targetView.requestFocus(); 1750 } 1751 if (updateScrollPosition(targetView, false, mTempDeltas)) { 1752 int dx, dy; 1753 if (mOrientation == HORIZONTAL) { 1754 dx = mTempDeltas[0]; 1755 dy = mTempDeltas[1]; 1756 } else { 1757 dx = mTempDeltas[1]; 1758 dy = mTempDeltas[0]; 1759 } 1760 final int distance = (int) Math.sqrt(dx * dx + dy * dy); 1761 final int time = calculateTimeForDeceleration(distance); 1762 action.update(dx, dy, time, mDecelerateInterpolator); 1763 } 1764 } 1765 }; 1766 linearSmoothScroller.setTargetPosition(position); 1767 startSmoothScroll(linearSmoothScroller); 1768 } else { 1769 mForceFullLayout = true; 1770 parent.requestLayout(); 1771 } 1772 } 1773 } 1774 1775 @Override 1776 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 1777 boolean needsLayout = false; 1778 if (itemCount != 0) { 1779 if (mFirstVisiblePos < 0) { 1780 needsLayout = true; 1781 } else if (!(positionStart > mLastVisiblePos + 1 || 1782 positionStart + itemCount < mFirstVisiblePos - 1)) { 1783 needsLayout = true; 1784 } 1785 } 1786 if (needsLayout) { 1787 recyclerView.requestLayout(); 1788 } 1789 } 1790 1791 @Override 1792 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 1793 if (mFocusSearchDisabled) { 1794 return true; 1795 } 1796 if (!mInLayout) { 1797 scrollToView(child, true); 1798 } 1799 return true; 1800 } 1801 1802 @Override 1803 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 1804 boolean immediate) { 1805 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 1806 return false; 1807 } 1808 1809 int getScrollOffsetX() { 1810 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 1811 } 1812 1813 int getScrollOffsetY() { 1814 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 1815 } 1816 1817 public void getViewSelectedOffsets(View view, int[] offsets) { 1818 int scrollOffsetX = getScrollOffsetX(); 1819 int scrollOffsetY = getScrollOffsetY(); 1820 int viewCenterX = scrollOffsetX + getViewCenterX(view); 1821 int viewCenterY = scrollOffsetY + getViewCenterY(view); 1822 offsets[0] = mWindowAlignment.horizontal.getSystemScrollPos(viewCenterX) - scrollOffsetX; 1823 offsets[1] = mWindowAlignment.vertical.getSystemScrollPos(viewCenterY) - scrollOffsetY; 1824 } 1825 1826 /** 1827 * Scroll to a given child view and change mFocusPosition. 1828 */ 1829 private void scrollToView(View view, boolean smooth) { 1830 int newFocusPosition = getPositionByView(view); 1831 if (mInLayout || newFocusPosition != mFocusPosition) { 1832 mFocusPosition = newFocusPosition; 1833 if (mState == null || !mState.isPreLayout()) { 1834 dispatchChildSelected(); 1835 } 1836 } 1837 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 1838 mBaseGridView.invalidate(); 1839 } 1840 if (view == null) { 1841 return; 1842 } 1843 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 1844 // transfer focus to the child if it does not have focus yet (e.g. triggered 1845 // by setSelection()) 1846 view.requestFocus(); 1847 } 1848 if (updateScrollPosition(view, mInLayout, mTempDeltas)) { 1849 scrollGrid(mTempDeltas[0], mTempDeltas[1], smooth); 1850 } 1851 } 1852 1853 private boolean updateScrollPosition(View view, boolean force, int[] deltas) { 1854 switch (mFocusScrollStrategy) { 1855 case BaseGridView.FOCUS_SCROLL_ALIGNED: 1856 default: 1857 return updateAlignedPosition(view, force, deltas); 1858 case BaseGridView.FOCUS_SCROLL_ITEM: 1859 case BaseGridView.FOCUS_SCROLL_PAGE: 1860 return updateNoneAlignedPosition(view, deltas); 1861 } 1862 } 1863 1864 private boolean updateNoneAlignedPosition(View view, int[] deltas) { 1865 int pos = getPositionByView(view); 1866 int viewMin = getViewMin(view); 1867 int viewMax = getViewMax(view); 1868 // we either align "firstView" to left/top padding edge 1869 // or align "lastView" to right/bottom padding edge 1870 View firstView = null; 1871 View lastView = null; 1872 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 1873 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 1874 final int row = mGrid.getLocation(pos).row; 1875 if (viewMin < paddingLow) { 1876 // view enters low padding area: 1877 firstView = view; 1878 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1879 // scroll one "page" left/top, 1880 // align first visible item of the "page" at the low padding edge. 1881 while (!prependOneVisibleItem()) { 1882 List<Integer> positions = 1883 mGrid.getItemPositionsInRows(mFirstVisiblePos, pos)[row]; 1884 firstView = findViewByPosition(positions.get(0)); 1885 if (viewMax - getViewMin(firstView) > clientSize) { 1886 if (positions.size() > 1) { 1887 firstView = findViewByPosition(positions.get(1)); 1888 } 1889 break; 1890 } 1891 } 1892 } 1893 } else if (viewMax > clientSize + paddingLow) { 1894 // view enters high padding area: 1895 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1896 // scroll whole one page right/bottom, align view at the low padding edge. 1897 firstView = view; 1898 do { 1899 List<Integer> positions = 1900 mGrid.getItemPositionsInRows(pos, mLastVisiblePos)[row]; 1901 lastView = findViewByPosition(positions.get(positions.size() - 1)); 1902 if (getViewMax(lastView) - viewMin > clientSize) { 1903 lastView = null; 1904 break; 1905 } 1906 } while (!appendOneVisibleItem()); 1907 if (lastView != null) { 1908 // however if we reached end, we should align last view. 1909 firstView = null; 1910 } 1911 } else { 1912 lastView = view; 1913 } 1914 } 1915 int scrollPrimary = 0; 1916 int scrollSecondary = 0; 1917 if (firstView != null) { 1918 scrollPrimary = getViewMin(firstView) - paddingLow; 1919 } else if (lastView != null) { 1920 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 1921 } 1922 View secondaryAlignedView; 1923 if (firstView != null) { 1924 secondaryAlignedView = firstView; 1925 } else if (lastView != null) { 1926 secondaryAlignedView = lastView; 1927 } else { 1928 secondaryAlignedView = view; 1929 } 1930 int viewCenterSecondary = mScrollOffsetSecondary + 1931 getViewCenterSecondary(secondaryAlignedView); 1932 mWindowAlignment.secondAxis().updateScrollCenter(viewCenterSecondary); 1933 scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(); 1934 scrollSecondary -= mScrollOffsetSecondary; 1935 if (scrollPrimary != 0 || scrollSecondary != 0) { 1936 deltas[0] = scrollPrimary; 1937 deltas[1] = scrollSecondary; 1938 return true; 1939 } 1940 return false; 1941 } 1942 1943 private boolean updateAlignedPosition(View view, boolean force, int[] deltas) { 1944 int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 1945 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 1946 1947 if (force || viewCenterPrimary != mWindowAlignment.mainAxis().getScrollCenter() 1948 || viewCenterSecondary != mWindowAlignment.secondAxis().getScrollCenter()) { 1949 mWindowAlignment.mainAxis().updateScrollCenter(viewCenterPrimary); 1950 mWindowAlignment.secondAxis().updateScrollCenter(viewCenterSecondary); 1951 int scrollPrimary = mWindowAlignment.mainAxis().getSystemScrollPos(); 1952 int scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(); 1953 if (DEBUG) { 1954 Log.v(getTag(), "updateAlignedPosition " + scrollPrimary + " " + scrollSecondary 1955 +" " + mWindowAlignment); 1956 } 1957 scrollPrimary -= mScrollOffsetPrimary; 1958 scrollSecondary -= mScrollOffsetSecondary; 1959 deltas[0] = scrollPrimary; 1960 deltas[1] = scrollSecondary; 1961 return true; 1962 } 1963 return false; 1964 } 1965 1966 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 1967 if (mInLayout) { 1968 scrollDirectionPrimary(scrollPrimary); 1969 scrollDirectionSecondary(scrollSecondary); 1970 } else { 1971 int scrollX; 1972 int scrollY; 1973 if (mOrientation == HORIZONTAL) { 1974 scrollX = scrollPrimary; 1975 scrollY = scrollSecondary; 1976 } else { 1977 scrollX = scrollSecondary; 1978 scrollY = scrollPrimary; 1979 } 1980 if (smooth) { 1981 mBaseGridView.smoothScrollBy(scrollX, scrollY); 1982 } else { 1983 mBaseGridView.scrollBy(scrollX, scrollY); 1984 } 1985 } 1986 } 1987 1988 public void setAnimateChildLayout(boolean animateChildLayout) { 1989 mAnimateChildLayout = animateChildLayout; 1990 } 1991 1992 public boolean isChildLayoutAnimated() { 1993 return mAnimateChildLayout; 1994 } 1995 1996 public void setPruneChild(boolean pruneChild) { 1997 if (mPruneChild != pruneChild) { 1998 mPruneChild = pruneChild; 1999 if (mPruneChild) { 2000 requestLayout(); 2001 } 2002 } 2003 } 2004 2005 public boolean getPruneChild() { 2006 return mPruneChild; 2007 } 2008 2009 private int findImmediateChildIndex(View view) { 2010 while (view != null && view != mBaseGridView) { 2011 int index = mBaseGridView.indexOfChild(view); 2012 if (index >= 0) { 2013 return index; 2014 } 2015 view = (View) view.getParent(); 2016 } 2017 return NO_POSITION; 2018 } 2019 2020 void setFocusSearchDisabled(boolean disabled) { 2021 mFocusSearchDisabled = disabled; 2022 } 2023 2024 boolean isFocusSearchDisabled() { 2025 return mFocusSearchDisabled; 2026 } 2027 2028 @Override 2029 public View onInterceptFocusSearch(View focused, int direction) { 2030 if (mFocusSearchDisabled) { 2031 return focused; 2032 } 2033 return null; 2034 } 2035 2036 boolean hasNextViewInSameRow(int pos) { 2037 if (mGrid == null || pos == NO_POSITION) { 2038 return false; 2039 } 2040 final int focusedRow = mGrid.getLocation(pos).row; 2041 for (int i = 0, count = getChildCount(); i < count; i++) { 2042 int position = getPositionByIndex(i); 2043 StaggeredGrid.Location loc = mGrid.getLocation(position); 2044 if (loc != null && loc.row == focusedRow) { 2045 if (position > pos) { 2046 return true; 2047 } 2048 } 2049 } 2050 return false; 2051 } 2052 2053 boolean hasPreviousViewInSameRow(int pos) { 2054 if (mGrid == null || pos == NO_POSITION) { 2055 return false; 2056 } 2057 final int focusedRow = mGrid.getLocation(pos).row; 2058 for (int i = getChildCount() - 1; i >= 0; i--) { 2059 int position = getPositionByIndex(i); 2060 StaggeredGrid.Location loc = mGrid.getLocation(position); 2061 if (loc != null && loc.row == focusedRow) { 2062 if (position < pos) { 2063 return true; 2064 } 2065 } 2066 } 2067 return false; 2068 } 2069 2070 @Override 2071 public boolean onAddFocusables(RecyclerView recyclerView, 2072 ArrayList<View> views, int direction, int focusableMode) { 2073 if (mFocusSearchDisabled) { 2074 return true; 2075 } 2076 // If this viewgroup or one of its children currently has focus then we 2077 // consider our children for focus searching in main direction on the same row. 2078 // If this viewgroup has no focus and using focus align, we want the system 2079 // to ignore our children and pass focus to the viewgroup, which will pass 2080 // focus on to its children appropriately. 2081 // If this viewgroup has no focus and not using focus align, we want to 2082 // consider the child that does not overlap with padding area. 2083 if (recyclerView.hasFocus()) { 2084 final int movement = getMovement(direction); 2085 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2086 // Move on secondary direction uses default addFocusables(). 2087 return false; 2088 } 2089 final View focused = recyclerView.findFocus(); 2090 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2091 // Add focusables of focused item. 2092 if (focusedPos != NO_POSITION) { 2093 findViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2094 } 2095 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2096 mGrid.getLocation(focusedPos).row : NO_POSITION; 2097 // Add focusables of next neighbor of same row on the focus search direction. 2098 if (mGrid != null) { 2099 final int focusableCount = views.size(); 2100 for (int i = 0, count = getChildCount(); i < count; i++) { 2101 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2102 final View child = getChildAt(index); 2103 if (child.getVisibility() != View.VISIBLE) { 2104 continue; 2105 } 2106 int position = getPositionByIndex(index); 2107 StaggeredGrid.Location loc = mGrid.getLocation(position); 2108 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2109 if (focusedPos == NO_POSITION || 2110 (movement == NEXT_ITEM && position > focusedPos) 2111 || (movement == PREV_ITEM && position < focusedPos)) { 2112 child.addFocusables(views, direction, focusableMode); 2113 if (views.size() > focusableCount) { 2114 break; 2115 } 2116 } 2117 } 2118 } 2119 } 2120 } else { 2121 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2122 // adding views not overlapping padding area to avoid scrolling in gaining focus 2123 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2124 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2125 int focusableCount = views.size(); 2126 for (int i = 0, count = getChildCount(); i < count; i++) { 2127 View child = getChildAt(i); 2128 if (child.getVisibility() == View.VISIBLE) { 2129 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2130 child.addFocusables(views, direction, focusableMode); 2131 } 2132 } 2133 } 2134 // if we cannot find any, then just add all children. 2135 if (views.size() == focusableCount) { 2136 for (int i = 0, count = getChildCount(); i < count; i++) { 2137 View child = getChildAt(i); 2138 if (child.getVisibility() == View.VISIBLE) { 2139 child.addFocusables(views, direction, focusableMode); 2140 } 2141 } 2142 if (views.size() != focusableCount) { 2143 return true; 2144 } 2145 } else { 2146 return true; 2147 } 2148 // if still cannot find any, fall through and add itself 2149 } 2150 if (recyclerView.isFocusable()) { 2151 views.add(recyclerView); 2152 } 2153 } 2154 return true; 2155 } 2156 2157 @Override 2158 public View onFocusSearchFailed(View focused, int direction, Recycler recycler, 2159 RecyclerView.State state) { 2160 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2161 2162 saveContext(recycler, state); 2163 View view = null; 2164 int movement = getMovement(direction); 2165 final FocusFinder ff = FocusFinder.getInstance(); 2166 if (movement == NEXT_ITEM) { 2167 while (view == null && !appendOneVisibleItem()) { 2168 view = ff.findNextFocus(mBaseGridView, focused, direction); 2169 } 2170 } else if (movement == PREV_ITEM){ 2171 while (view == null && !prependOneVisibleItem()) { 2172 view = ff.findNextFocus(mBaseGridView, focused, direction); 2173 } 2174 } 2175 if (view == null) { 2176 // returning the same view to prevent focus lost when scrolling past the end of the list 2177 if (movement == PREV_ITEM) { 2178 view = mFocusOutFront ? null : focused; 2179 } else if (movement == NEXT_ITEM){ 2180 view = mFocusOutEnd ? null : focused; 2181 } 2182 } 2183 leaveContext(); 2184 if (DEBUG) Log.v(getTag(), "returning view " + view); 2185 return view; 2186 } 2187 2188 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2189 Rect previouslyFocusedRect) { 2190 switch (mFocusScrollStrategy) { 2191 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2192 default: 2193 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2194 direction, previouslyFocusedRect); 2195 case BaseGridView.FOCUS_SCROLL_PAGE: 2196 case BaseGridView.FOCUS_SCROLL_ITEM: 2197 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2198 direction, previouslyFocusedRect); 2199 } 2200 } 2201 2202 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2203 int direction, Rect previouslyFocusedRect) { 2204 View view = findViewByPosition(mFocusPosition); 2205 if (view != null) { 2206 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2207 if (!result && DEBUG) { 2208 Log.w(getTag(), "failed to request focus on " + view); 2209 } 2210 return result; 2211 } 2212 return false; 2213 } 2214 2215 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2216 int direction, Rect previouslyFocusedRect) { 2217 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2218 int index; 2219 int increment; 2220 int end; 2221 int count = getChildCount(); 2222 if ((direction & View.FOCUS_FORWARD) != 0) { 2223 index = 0; 2224 increment = 1; 2225 end = count; 2226 } else { 2227 index = count - 1; 2228 increment = -1; 2229 end = -1; 2230 } 2231 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2232 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2233 for (int i = index; i != end; i += increment) { 2234 View child = getChildAt(i); 2235 if (child.getVisibility() == View.VISIBLE) { 2236 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2237 if (child.requestFocus(direction, previouslyFocusedRect)) { 2238 return true; 2239 } 2240 } 2241 } 2242 } 2243 return false; 2244 } 2245 2246 private final static int PREV_ITEM = 0; 2247 private final static int NEXT_ITEM = 1; 2248 private final static int PREV_ROW = 2; 2249 private final static int NEXT_ROW = 3; 2250 2251 private int getMovement(int direction) { 2252 int movement = View.FOCUS_LEFT; 2253 2254 if (mOrientation == HORIZONTAL) { 2255 switch(direction) { 2256 case View.FOCUS_LEFT: 2257 movement = PREV_ITEM; 2258 break; 2259 case View.FOCUS_RIGHT: 2260 movement = NEXT_ITEM; 2261 break; 2262 case View.FOCUS_UP: 2263 movement = PREV_ROW; 2264 break; 2265 case View.FOCUS_DOWN: 2266 movement = NEXT_ROW; 2267 break; 2268 } 2269 } else if (mOrientation == VERTICAL) { 2270 switch(direction) { 2271 case View.FOCUS_LEFT: 2272 movement = PREV_ROW; 2273 break; 2274 case View.FOCUS_RIGHT: 2275 movement = NEXT_ROW; 2276 break; 2277 case View.FOCUS_UP: 2278 movement = PREV_ITEM; 2279 break; 2280 case View.FOCUS_DOWN: 2281 movement = NEXT_ITEM; 2282 break; 2283 } 2284 } 2285 2286 return movement; 2287 } 2288 2289 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2290 View view = findViewByPosition(mFocusPosition); 2291 if (view == null) { 2292 return i; 2293 } 2294 int focusIndex = recyclerView.indexOfChild(view); 2295 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2296 // drawing order is 0 1 2 3 9 8 7 6 5 4 2297 if (i < focusIndex) { 2298 return i; 2299 } else if (i < childCount - 1) { 2300 return focusIndex + childCount - 1 - i; 2301 } else { 2302 return focusIndex; 2303 } 2304 } 2305 2306 @Override 2307 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2308 RecyclerView.Adapter newAdapter) { 2309 discardLayoutInfo(); 2310 mFocusPosition = NO_POSITION; 2311 super.onAdapterChanged(oldAdapter, newAdapter); 2312 } 2313 2314 private void discardLayoutInfo() { 2315 mGrid = null; 2316 mRows = null; 2317 mRowSizeSecondary = null; 2318 mFirstVisiblePos = -1; 2319 mLastVisiblePos = -1; 2320 mRowSecondarySizeRefresh = false; 2321 } 2322 2323 public void setLayoutEnabled(boolean layoutEnabled) { 2324 if (mLayoutEnabled != layoutEnabled) { 2325 mLayoutEnabled = layoutEnabled; 2326 requestLayout(); 2327 } 2328 } 2329} 2330