GridLayoutManager.java revision b300ce0dfc3ad41fd6fef25833dfe4b14d5261d2
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.view.ViewCompat; 23import android.support.v7.widget.LinearSmoothScroller; 24import android.support.v7.widget.RecyclerView; 25import android.support.v7.widget.RecyclerView.Recycler; 26import android.support.v7.widget.RecyclerView.State; 27 28import static android.support.v7.widget.RecyclerView.NO_ID; 29import static android.support.v7.widget.RecyclerView.NO_POSITION; 30import static android.support.v7.widget.RecyclerView.HORIZONTAL; 31import static android.support.v7.widget.RecyclerView.VERTICAL; 32 33import android.util.AttributeSet; 34import android.util.Log; 35import android.view.FocusFinder; 36import android.view.Gravity; 37import android.view.View; 38import android.view.ViewParent; 39import android.view.View.MeasureSpec; 40import android.view.ViewGroup.MarginLayoutParams; 41import android.view.ViewGroup; 42 43import java.io.PrintWriter; 44import java.io.StringWriter; 45import java.util.ArrayList; 46import java.util.List; 47 48final class GridLayoutManager extends RecyclerView.LayoutManager { 49 50 /* 51 * LayoutParams for {@link HorizontalGridView} and {@link VerticalGridView}. 52 * The class currently does two internal jobs: 53 * - Saves optical bounds insets. 54 * - Caches focus align view center. 55 */ 56 static class LayoutParams extends RecyclerView.LayoutParams { 57 58 // The view is saved only during animation. 59 private View mView; 60 61 // For placement 62 private int mLeftInset; 63 private int mTopInset; 64 private int mRighInset; 65 private int mBottomInset; 66 67 // For alignment 68 private int mAlignX; 69 private int mAlignY; 70 71 public LayoutParams(Context c, AttributeSet attrs) { 72 super(c, attrs); 73 } 74 75 public LayoutParams(int width, int height) { 76 super(width, height); 77 } 78 79 public LayoutParams(MarginLayoutParams source) { 80 super(source); 81 } 82 83 public LayoutParams(ViewGroup.LayoutParams source) { 84 super(source); 85 } 86 87 public LayoutParams(RecyclerView.LayoutParams source) { 88 super(source); 89 } 90 91 public LayoutParams(LayoutParams source) { 92 super(source); 93 } 94 95 int getAlignX() { 96 return mAlignX; 97 } 98 99 int getAlignY() { 100 return mAlignY; 101 } 102 103 int getOpticalLeft(View view) { 104 return view.getLeft() + mLeftInset; 105 } 106 107 int getOpticalTop(View view) { 108 return view.getTop() + mTopInset; 109 } 110 111 int getOpticalRight(View view) { 112 return view.getRight() - mRighInset; 113 } 114 115 int getOpticalBottom(View view) { 116 return view.getBottom() - mBottomInset; 117 } 118 119 int getOpticalWidth(View view) { 120 return view.getWidth() - mLeftInset - mRighInset; 121 } 122 123 int getOpticalHeight(View view) { 124 return view.getHeight() - mTopInset - mBottomInset; 125 } 126 127 int getOpticalLeftInset() { 128 return mLeftInset; 129 } 130 131 int getOpticalRightInset() { 132 return mRighInset; 133 } 134 135 int getOpticalTopInset() { 136 return mTopInset; 137 } 138 139 int getOpticalBottomInset() { 140 return mBottomInset; 141 } 142 143 void setAlignX(int alignX) { 144 mAlignX = alignX; 145 } 146 147 void setAlignY(int alignY) { 148 mAlignY = alignY; 149 } 150 151 void setOpticalInsets(int leftInset, int topInset, int rightInset, int bottomInset) { 152 mLeftInset = leftInset; 153 mTopInset = topInset; 154 mRighInset = rightInset; 155 mBottomInset = bottomInset; 156 } 157 158 private void invalidateItemDecoration() { 159 ViewParent parent = mView.getParent(); 160 if (parent instanceof RecyclerView) { 161 // TODO: we only need invalidate parent if it has ItemDecoration 162 ((RecyclerView) parent).invalidate(); 163 } 164 } 165 } 166 167 private static final String TAG = "GridLayoutManager"; 168 private static final boolean DEBUG = false; 169 170 private String getTag() { 171 return TAG + ":" + mBaseGridView.getId(); 172 } 173 174 private final BaseGridView mBaseGridView; 175 176 /** 177 * The orientation of a "row". 178 */ 179 private int mOrientation = HORIZONTAL; 180 181 private RecyclerView.State mState; 182 private RecyclerView.Recycler mRecycler; 183 184 private boolean mInLayout = false; 185 private boolean mInSelection = false; 186 187 private OnChildSelectedListener mChildSelectedListener = null; 188 189 /** 190 * The focused position, it's not the currently visually aligned position 191 * but it is the final position that we intend to focus on. If there are 192 * multiple setSelection() called, mFocusPosition saves last value. 193 */ 194 private int mFocusPosition = NO_POSITION; 195 196 /** 197 * The offset to be applied to mFocusPosition, due to adapter change, on the next 198 * layout. Set to Integer.MIN_VALUE means item was removed. 199 * TODO: This is somewhat duplication of RecyclerView getOldPosition() which is 200 * unfortunately cleared after prelayout. 201 */ 202 private int mFocusPositionOffset = 0; 203 204 /** 205 * Force a full layout under certain situations. 206 */ 207 private boolean mForceFullLayout; 208 209 /** 210 * True if layout is enabled. 211 */ 212 private boolean mLayoutEnabled = true; 213 214 /** 215 * The scroll offsets of the viewport relative to the entire view. 216 */ 217 private int mScrollOffsetPrimary; 218 private int mScrollOffsetSecondary; 219 220 /** 221 * User-specified row height/column width. Can be WRAP_CONTENT. 222 */ 223 private int mRowSizeSecondaryRequested; 224 225 /** 226 * The fixed size of each grid item in the secondary direction. This corresponds to 227 * the row height, equal for all rows. Grid items may have variable length 228 * in the primary direction. 229 */ 230 private int mFixedRowSizeSecondary; 231 232 /** 233 * Tracks the secondary size of each row. 234 */ 235 private int[] mRowSizeSecondary; 236 237 /** 238 * Flag controlling whether the current/next layout should 239 * be updating the secondary size of rows. 240 */ 241 private boolean mRowSecondarySizeRefresh; 242 243 /** 244 * The maximum measured size of the view. 245 */ 246 private int mMaxSizeSecondary; 247 248 /** 249 * Margin between items. 250 */ 251 private int mHorizontalMargin; 252 /** 253 * Margin between items vertically. 254 */ 255 private int mVerticalMargin; 256 /** 257 * Margin in main direction. 258 */ 259 private int mMarginPrimary; 260 /** 261 * Margin in second direction. 262 */ 263 private int mMarginSecondary; 264 /** 265 * How to position child in secondary direction. 266 */ 267 private int mGravity = Gravity.LEFT | Gravity.TOP; 268 /** 269 * The number of rows in the grid. 270 */ 271 private int mNumRows; 272 /** 273 * Number of rows requested, can be 0 to be determined by parent size and 274 * rowHeight. 275 */ 276 private int mNumRowsRequested = 1; 277 278 /** 279 * Tracking start/end position of each row for visible items. 280 */ 281 private StaggeredGrid.Row[] mRows; 282 283 /** 284 * Saves grid information of each view. 285 */ 286 private StaggeredGrid mGrid; 287 /** 288 * Position of first item (included) that has attached views. 289 */ 290 private int mFirstVisiblePos; 291 /** 292 * Position of last item (included) that has attached views. 293 */ 294 private int mLastVisiblePos; 295 296 /** 297 * Focus Scroll strategy. 298 */ 299 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 300 /** 301 * Defines how item view is aligned in the window. 302 */ 303 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 304 305 /** 306 * Defines how item view is aligned. 307 */ 308 private final ItemAlignment mItemAlignment = new ItemAlignment(); 309 310 /** 311 * Dimensions of the view, width or height depending on orientation. 312 */ 313 private int mSizePrimary; 314 315 /** 316 * Allow DPAD key to navigate out at the front of the View (where position = 0), 317 * default is false. 318 */ 319 private boolean mFocusOutFront; 320 321 /** 322 * Allow DPAD key to navigate out at the end of the view, default is false. 323 */ 324 private boolean mFocusOutEnd; 325 326 /** 327 * True if focus search is disabled. 328 */ 329 private boolean mFocusSearchDisabled; 330 331 /** 332 * True if prune child, might be disabled during transition. 333 */ 334 private boolean mPruneChild = true; 335 336 /** 337 * True if scroll content, might be disabled during transition. 338 */ 339 private boolean mScrollEnabled = true; 340 341 private int[] mTempDeltas = new int[2]; 342 343 /** 344 * Temporaries used for measuring. 345 */ 346 private int[] mMeasuredDimension = new int[2]; 347 348 SavedState mLoadingState; 349 final ViewsStateBundle mChildrenStates = new ViewsStateBundle( 350 ViewsStateBundle.SAVE_LIMITED_CHILD, ViewsStateBundle.DEFAULT_LIMIT); 351 352 public GridLayoutManager(BaseGridView baseGridView) { 353 mBaseGridView = baseGridView; 354 } 355 356 public void setOrientation(int orientation) { 357 if (orientation != HORIZONTAL && orientation != VERTICAL) { 358 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 359 return; 360 } 361 362 mOrientation = orientation; 363 mWindowAlignment.setOrientation(orientation); 364 mItemAlignment.setOrientation(orientation); 365 mForceFullLayout = true; 366 } 367 368 public int getFocusScrollStrategy() { 369 return mFocusScrollStrategy; 370 } 371 372 public void setFocusScrollStrategy(int focusScrollStrategy) { 373 mFocusScrollStrategy = focusScrollStrategy; 374 } 375 376 public void setWindowAlignment(int windowAlignment) { 377 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 378 } 379 380 public int getWindowAlignment() { 381 return mWindowAlignment.mainAxis().getWindowAlignment(); 382 } 383 384 public void setWindowAlignmentOffset(int alignmentOffset) { 385 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 386 } 387 388 public int getWindowAlignmentOffset() { 389 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 390 } 391 392 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 393 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 394 } 395 396 public float getWindowAlignmentOffsetPercent() { 397 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 398 } 399 400 public void setItemAlignmentOffset(int alignmentOffset) { 401 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 402 updateChildAlignments(); 403 } 404 405 public int getItemAlignmentOffset() { 406 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 407 } 408 409 public void setItemAlignmentOffsetWithPadding(boolean withPadding) { 410 mItemAlignment.mainAxis().setItemAlignmentOffsetWithPadding(withPadding); 411 updateChildAlignments(); 412 } 413 414 public boolean isItemAlignmentOffsetWithPadding() { 415 return mItemAlignment.mainAxis().isItemAlignmentOffsetWithPadding(); 416 } 417 418 public void setItemAlignmentOffsetPercent(float offsetPercent) { 419 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 420 updateChildAlignments(); 421 } 422 423 public float getItemAlignmentOffsetPercent() { 424 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 425 } 426 427 public void setItemAlignmentViewId(int viewId) { 428 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 429 updateChildAlignments(); 430 } 431 432 public int getItemAlignmentViewId() { 433 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 434 } 435 436 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 437 mFocusOutFront = throughFront; 438 mFocusOutEnd = throughEnd; 439 } 440 441 public void setNumRows(int numRows) { 442 if (numRows < 0) throw new IllegalArgumentException(); 443 mNumRowsRequested = numRows; 444 mForceFullLayout = true; 445 } 446 447 /** 448 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 449 */ 450 public void setRowHeight(int height) { 451 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 452 mRowSizeSecondaryRequested = height; 453 } else { 454 throw new IllegalArgumentException("Invalid row height: " + height); 455 } 456 } 457 458 public void setItemMargin(int margin) { 459 mVerticalMargin = mHorizontalMargin = margin; 460 mMarginPrimary = mMarginSecondary = margin; 461 } 462 463 public void setVerticalMargin(int margin) { 464 if (mOrientation == HORIZONTAL) { 465 mMarginSecondary = mVerticalMargin = margin; 466 } else { 467 mMarginPrimary = mVerticalMargin = margin; 468 } 469 } 470 471 public void setHorizontalMargin(int margin) { 472 if (mOrientation == HORIZONTAL) { 473 mMarginPrimary = mHorizontalMargin = margin; 474 } else { 475 mMarginSecondary = mHorizontalMargin = margin; 476 } 477 } 478 479 public int getVerticalMargin() { 480 return mVerticalMargin; 481 } 482 483 public int getHorizontalMargin() { 484 return mHorizontalMargin; 485 } 486 487 public void setGravity(int gravity) { 488 mGravity = gravity; 489 } 490 491 protected boolean hasDoneFirstLayout() { 492 return mGrid != null; 493 } 494 495 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 496 mChildSelectedListener = listener; 497 } 498 499 private int getPositionByView(View view) { 500 if (view == null) { 501 return NO_POSITION; 502 } 503 LayoutParams params = (LayoutParams) view.getLayoutParams(); 504 if (params == null || params.isItemRemoved()) { 505 // when item is removed, the position value can be any value. 506 return NO_POSITION; 507 } 508 return params.getViewPosition(); 509 } 510 511 private int getPositionByIndex(int index) { 512 return getPositionByView(getChildAt(index)); 513 } 514 515 private void dispatchChildSelected() { 516 if (mChildSelectedListener == null) { 517 return; 518 } 519 if (mFocusPosition != NO_POSITION) { 520 View view = findViewByPosition(mFocusPosition); 521 if (view != null) { 522 RecyclerView.ViewHolder vh = mBaseGridView.getChildViewHolder(view); 523 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 524 vh == null? NO_ID: vh.getItemId()); 525 return; 526 } 527 } 528 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 529 } 530 531 @Override 532 public boolean canScrollHorizontally() { 533 // We can scroll horizontally if we have horizontal orientation, or if 534 // we are vertical and have more than one column. 535 return mOrientation == HORIZONTAL || mNumRows > 1; 536 } 537 538 @Override 539 public boolean canScrollVertically() { 540 // We can scroll vertically if we have vertical orientation, or if we 541 // are horizontal and have more than one row. 542 return mOrientation == VERTICAL || mNumRows > 1; 543 } 544 545 @Override 546 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 547 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 548 ViewGroup.LayoutParams.WRAP_CONTENT); 549 } 550 551 @Override 552 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 553 return new LayoutParams(context, attrs); 554 } 555 556 @Override 557 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 558 if (lp instanceof LayoutParams) { 559 return new LayoutParams((LayoutParams) lp); 560 } else if (lp instanceof RecyclerView.LayoutParams) { 561 return new LayoutParams((RecyclerView.LayoutParams) lp); 562 } else if (lp instanceof MarginLayoutParams) { 563 return new LayoutParams((MarginLayoutParams) lp); 564 } else { 565 return new LayoutParams(lp); 566 } 567 } 568 569 protected View getViewForPosition(int position) { 570 return mRecycler.getViewForPosition(position); 571 } 572 573 final int getOpticalLeft(View v) { 574 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 575 } 576 577 final int getOpticalRight(View v) { 578 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 579 } 580 581 final int getOpticalTop(View v) { 582 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 583 } 584 585 final int getOpticalBottom(View v) { 586 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 587 } 588 589 private int getViewMin(View v) { 590 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 591 } 592 593 private int getViewMax(View v) { 594 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 595 } 596 597 private int getViewCenter(View view) { 598 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 599 } 600 601 private int getViewCenterSecondary(View view) { 602 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 603 } 604 605 private int getViewCenterX(View v) { 606 LayoutParams p = (LayoutParams) v.getLayoutParams(); 607 return p.getOpticalLeft(v) + p.getAlignX(); 608 } 609 610 private int getViewCenterY(View v) { 611 LayoutParams p = (LayoutParams) v.getLayoutParams(); 612 return p.getOpticalTop(v) + p.getAlignY(); 613 } 614 615 /** 616 * Save Recycler and State for convenience. Must be paired with leaveContext(). 617 */ 618 private void saveContext(Recycler recycler, State state) { 619 if (mRecycler != null || mState != null) { 620 Log.e(TAG, "Recycler information was not released, bug!"); 621 } 622 mRecycler = recycler; 623 mState = state; 624 } 625 626 /** 627 * Discard saved Recycler and State. 628 */ 629 private void leaveContext() { 630 mRecycler = null; 631 mState = null; 632 } 633 634 /** 635 * Re-initialize data structures for a data change or handling invisible 636 * selection. The method tries its best to preserve position information so 637 * that staggered grid looks same before and after re-initialize. 638 * @param focusPosition The initial focusPosition that we would like to 639 * focus on. 640 * @return Actual position that can be focused on. 641 */ 642 private int init(int focusPosition) { 643 644 final int newItemCount = mState.getItemCount(); 645 646 if (focusPosition == NO_POSITION && newItemCount > 0) { 647 // if focus position is never set before, initialize it to 0 648 focusPosition = 0; 649 } 650 // If adapter has changed then caches are invalid; otherwise, 651 // we try to maintain each row's position if number of rows keeps the same 652 // and existing mGrid contains the focusPosition. 653 if (mRows != null && mNumRows == mRows.length && 654 mGrid != null && mGrid.getSize() > 0 && focusPosition >= 0 && 655 focusPosition >= mGrid.getFirstIndex() && 656 focusPosition <= mGrid.getLastIndex()) { 657 // strip mGrid to a subset (like a column) that contains focusPosition 658 mGrid.stripDownTo(focusPosition); 659 // make sure that remaining items do not exceed new adapter size 660 int firstIndex = mGrid.getFirstIndex(); 661 int lastIndex = mGrid.getLastIndex(); 662 if (DEBUG) { 663 Log .v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " + lastIndex); 664 } 665 for (int i = lastIndex; i >=firstIndex; i--) { 666 if (i >= newItemCount) { 667 mGrid.removeLast(); 668 } 669 } 670 if (mGrid.getSize() == 0) { 671 focusPosition = newItemCount - 1; 672 // initialize row start locations 673 for (int i = 0; i < mNumRows; i++) { 674 mRows[i].low = 0; 675 mRows[i].high = 0; 676 } 677 if (DEBUG) Log.v(getTag(), "mGrid zero size"); 678 } else { 679 // initialize row start locations 680 for (int i = 0; i < mNumRows; i++) { 681 mRows[i].low = Integer.MAX_VALUE; 682 mRows[i].high = Integer.MIN_VALUE; 683 } 684 firstIndex = mGrid.getFirstIndex(); 685 lastIndex = mGrid.getLastIndex(); 686 if (focusPosition > lastIndex) { 687 focusPosition = mGrid.getLastIndex(); 688 } 689 if (DEBUG) { 690 Log.v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " 691 + lastIndex + " focusPosition " + focusPosition); 692 } 693 // fill rows with minimal view positions of the subset 694 for (int i = firstIndex; i <= lastIndex; i++) { 695 View v = findViewByPosition(i); 696 if (v == null) { 697 continue; 698 } 699 int row = mGrid.getLocation(i).row; 700 int low = getViewMin(v) + mScrollOffsetPrimary; 701 if (low < mRows[row].low) { 702 mRows[row].low = mRows[row].high = low; 703 } 704 } 705 int firstItemRowPosition = mRows[mGrid.getLocation(firstIndex).row].low; 706 if (firstItemRowPosition == Integer.MAX_VALUE) { 707 firstItemRowPosition = 0; 708 } 709 if (mState.didStructureChange()) { 710 // if there is structure change, the removed item might be in the 711 // subset, so it is meaningless to maintain the low locations. 712 for (int i = 0; i < mNumRows; i++) { 713 mRows[i].low = firstItemRowPosition; 714 mRows[i].high = firstItemRowPosition; 715 } 716 } else { 717 // fill other rows that does not include the subset using first item 718 for (int i = 0; i < mNumRows; i++) { 719 if (mRows[i].low == Integer.MAX_VALUE) { 720 mRows[i].low = mRows[i].high = firstItemRowPosition; 721 } 722 } 723 } 724 } 725 726 // Same adapter, we can reuse any attached views 727 detachAndScrapAttachedViews(mRecycler); 728 729 } else { 730 // otherwise recreate data structure 731 mRows = new StaggeredGrid.Row[mNumRows]; 732 733 for (int i = 0; i < mNumRows; i++) { 734 mRows[i] = new StaggeredGrid.Row(); 735 } 736 mGrid = new StaggeredGridDefault(); 737 if (newItemCount == 0) { 738 focusPosition = NO_POSITION; 739 } else if (focusPosition >= newItemCount) { 740 focusPosition = newItemCount - 1; 741 } 742 743 // Adapter may have changed so remove all attached views permanently 744 removeAndRecycleAllViews(mRecycler); 745 746 mScrollOffsetPrimary = 0; 747 mScrollOffsetSecondary = 0; 748 mWindowAlignment.reset(); 749 } 750 751 mGrid.setProvider(mGridProvider); 752 // mGrid share the same Row array information 753 mGrid.setRows(mRows); 754 mFirstVisiblePos = mLastVisiblePos = NO_POSITION; 755 756 initScrollController(); 757 updateScrollSecondAxis(); 758 759 return focusPosition; 760 } 761 762 private int getRowSizeSecondary(int rowIndex) { 763 if (mFixedRowSizeSecondary != 0) { 764 return mFixedRowSizeSecondary; 765 } 766 if (mRowSizeSecondary == null) { 767 return 0; 768 } 769 return mRowSizeSecondary[rowIndex]; 770 } 771 772 private int getRowStartSecondary(int rowIndex) { 773 int start = 0; 774 for (int i = 0; i < rowIndex; i++) { 775 start += getRowSizeSecondary(i) + mMarginSecondary; 776 } 777 return start; 778 } 779 780 private int getSizeSecondary() { 781 return getRowStartSecondary(mNumRows - 1) + getRowSizeSecondary(mNumRows - 1); 782 } 783 784 private void measureScrapChild(int position, int widthSpec, int heightSpec, 785 int[] measuredDimension) { 786 View view = mRecycler.getViewForPosition(position); 787 if (view != null) { 788 LayoutParams p = (LayoutParams) view.getLayoutParams(); 789 int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, 790 getPaddingLeft() + getPaddingRight(), p.width); 791 int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, 792 getPaddingTop() + getPaddingBottom(), p.height); 793 view.measure(childWidthSpec, childHeightSpec); 794 measuredDimension[0] = view.getMeasuredWidth(); 795 measuredDimension[1] = view.getMeasuredHeight(); 796 mRecycler.recycleView(view); 797 } 798 } 799 800 private boolean processRowSizeSecondary(boolean measure) { 801 if (mFixedRowSizeSecondary != 0) { 802 return false; 803 } 804 805 List<Integer>[] rows = mGrid == null ? null : 806 mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 807 boolean changed = false; 808 int scrapChildWidth = -1; 809 int scrapChildHeight = -1; 810 811 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 812 final int rowItemCount = rows == null ? 0 : rows[rowIndex].size(); 813 if (DEBUG) Log.v(getTag(), "processRowSizeSecondary row " + rowIndex + 814 " rowItemCount " + rowItemCount); 815 816 int rowSize = -1; 817 for (int i = 0; i < rowItemCount; i++) { 818 final View view = findViewByPosition(rows[rowIndex].get(i)); 819 if (view == null) { 820 continue; 821 } 822 if (measure && view.isLayoutRequested()) { 823 measureChild(view); 824 } 825 final int secondarySize = mOrientation == HORIZONTAL ? 826 view.getMeasuredHeight() : view.getMeasuredWidth(); 827 if (secondarySize > rowSize) { 828 rowSize = secondarySize; 829 } 830 } 831 832 if (measure && rowSize < 0 && mState.getItemCount() > 0) { 833 if (scrapChildWidth < 0 && scrapChildHeight < 0) { 834 measureScrapChild(mFocusPosition == NO_POSITION ? 0 : mFocusPosition, 835 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 836 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 837 mMeasuredDimension); 838 scrapChildWidth = mMeasuredDimension[0]; 839 scrapChildHeight = mMeasuredDimension[1]; 840 if (DEBUG) Log.v(TAG, "measured scrap child: " + scrapChildWidth + 841 " " + scrapChildHeight); 842 } 843 rowSize = mOrientation == HORIZONTAL ? scrapChildHeight : scrapChildWidth; 844 } 845 846 if (rowSize < 0) { 847 rowSize = 0; 848 } 849 850 if (DEBUG) Log.v(getTag(), "row " + rowIndex + " rowItemCount " + rowItemCount + 851 " rowSize " + rowSize); 852 853 if (mRowSizeSecondary[rowIndex] != rowSize) { 854 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 855 ", " + rowSize); 856 857 mRowSizeSecondary[rowIndex] = rowSize; 858 changed = true; 859 } 860 } 861 862 return changed; 863 } 864 865 /** 866 * Checks if we need to update row secondary sizes. 867 */ 868 private void updateRowSecondarySizeRefresh() { 869 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 870 if (mRowSecondarySizeRefresh) { 871 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 872 forceRequestLayout(); 873 } 874 } 875 876 private void forceRequestLayout() { 877 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 878 // RecyclerView prevents us from requesting layout in many cases 879 // (during layout, during scroll, etc.) 880 // For secondary row size wrap_content support we currently need a 881 // second layout pass to update the measured size after having measured 882 // and added child views in layoutChildren. 883 // Force the second layout by posting a delayed runnable. 884 // TODO: investigate allowing a second layout pass, 885 // or move child add/measure logic to the measure phase. 886 ViewCompat.postOnAnimation(mBaseGridView, mRequestLayoutRunnable); 887 } 888 889 private final Runnable mRequestLayoutRunnable = new Runnable() { 890 @Override 891 public void run() { 892 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 893 requestLayout(); 894 } 895 }; 896 897 @Override 898 public void onMeasure(Recycler recycler, State state, int widthSpec, int heightSpec) { 899 saveContext(recycler, state); 900 901 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 902 int measuredSizeSecondary; 903 if (mOrientation == HORIZONTAL) { 904 sizePrimary = MeasureSpec.getSize(widthSpec); 905 sizeSecondary = MeasureSpec.getSize(heightSpec); 906 modeSecondary = MeasureSpec.getMode(heightSpec); 907 paddingSecondary = getPaddingTop() + getPaddingBottom(); 908 } else { 909 sizeSecondary = MeasureSpec.getSize(widthSpec); 910 sizePrimary = MeasureSpec.getSize(heightSpec); 911 modeSecondary = MeasureSpec.getMode(widthSpec); 912 paddingSecondary = getPaddingLeft() + getPaddingRight(); 913 } 914 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 915 " heightSpec " + Integer.toHexString(heightSpec) + 916 " modeSecondary " + Integer.toHexString(modeSecondary) + 917 " sizeSecondary " + sizeSecondary + " " + this); 918 919 mMaxSizeSecondary = sizeSecondary; 920 921 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 922 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 923 mFixedRowSizeSecondary = 0; 924 925 if (mRowSizeSecondary == null || mRowSizeSecondary.length != mNumRows) { 926 mRowSizeSecondary = new int[mNumRows]; 927 } 928 929 // Measure all current children and update cached row heights 930 processRowSizeSecondary(true); 931 932 switch (modeSecondary) { 933 case MeasureSpec.UNSPECIFIED: 934 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 935 break; 936 case MeasureSpec.AT_MOST: 937 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 938 mMaxSizeSecondary); 939 break; 940 case MeasureSpec.EXACTLY: 941 measuredSizeSecondary = mMaxSizeSecondary; 942 break; 943 default: 944 throw new IllegalStateException("wrong spec"); 945 } 946 947 } else { 948 switch (modeSecondary) { 949 case MeasureSpec.UNSPECIFIED: 950 if (mRowSizeSecondaryRequested == 0) { 951 if (mOrientation == HORIZONTAL) { 952 throw new IllegalStateException("Must specify rowHeight or view height"); 953 } else { 954 throw new IllegalStateException("Must specify columnWidth or view width"); 955 } 956 } 957 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 958 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 959 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 960 * (mNumRows - 1) + paddingSecondary; 961 break; 962 case MeasureSpec.AT_MOST: 963 case MeasureSpec.EXACTLY: 964 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 965 mNumRows = 1; 966 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 967 } else if (mNumRowsRequested == 0) { 968 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 969 mNumRows = (sizeSecondary + mMarginSecondary) 970 / (mRowSizeSecondaryRequested + mMarginSecondary); 971 } else if (mRowSizeSecondaryRequested == 0) { 972 mNumRows = mNumRowsRequested; 973 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 974 * (mNumRows - 1)) / mNumRows; 975 } else { 976 mNumRows = mNumRowsRequested; 977 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 978 } 979 measuredSizeSecondary = sizeSecondary; 980 if (modeSecondary == MeasureSpec.AT_MOST) { 981 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 982 * (mNumRows - 1) + paddingSecondary; 983 if (childrenSize < measuredSizeSecondary) { 984 measuredSizeSecondary = childrenSize; 985 } 986 } 987 break; 988 default: 989 throw new IllegalStateException("wrong spec"); 990 } 991 } 992 if (mOrientation == HORIZONTAL) { 993 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 994 } else { 995 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 996 } 997 if (DEBUG) { 998 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 999 " measuredSizeSecondary " + measuredSizeSecondary + 1000 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1001 " mNumRows " + mNumRows); 1002 } 1003 1004 leaveContext(); 1005 } 1006 1007 private void measureChild(View child) { 1008 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1009 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1010 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1011 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1012 int widthSpec, heightSpec; 1013 1014 if (mOrientation == HORIZONTAL) { 1015 widthSpec = ViewGroup.getChildMeasureSpec( 1016 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1017 0, lp.width); 1018 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1019 } else { 1020 heightSpec = ViewGroup.getChildMeasureSpec( 1021 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1022 0, lp.height); 1023 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1024 } 1025 1026 child.measure(widthSpec, heightSpec); 1027 1028 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1029 " widthSpec " + Integer.toHexString(widthSpec) + 1030 " heightSpec " + Integer.toHexString(heightSpec) + 1031 " measuredWidth " + child.getMeasuredWidth() + 1032 " measuredHeight " + child.getMeasuredHeight()); 1033 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1034 } 1035 1036 private StaggeredGrid.Provider mGridProvider = new StaggeredGrid.Provider() { 1037 1038 @Override 1039 public int getCount() { 1040 return mState.getItemCount(); 1041 } 1042 1043 @Override 1044 public void createItem(int index, int rowIndex, boolean append) { 1045 View v = getViewForPosition(index); 1046 if (mFirstVisiblePos >= 0) { 1047 // when StaggeredGrid append or prepend item, we must guarantee 1048 // that sibling item has created views already. 1049 if (append && index != mLastVisiblePos + 1) { 1050 throw new RuntimeException(); 1051 } else if (!append && index != mFirstVisiblePos - 1) { 1052 throw new RuntimeException(); 1053 } 1054 } 1055 1056 // See recyclerView docs: we don't need re-add scraped view if it was removed. 1057 if (!((RecyclerView.LayoutParams) v.getLayoutParams()).isItemRemoved()) { 1058 if (append) { 1059 addView(v); 1060 } else { 1061 addView(v, 0); 1062 } 1063 measureChild(v); 1064 } 1065 1066 int length = mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1067 int start, end; 1068 final boolean rowIsEmpty = mRows[rowIndex].high == mRows[rowIndex].low; 1069 if (append) { 1070 if (!rowIsEmpty) { 1071 // if there are existing item in the row, add margin between 1072 start = mRows[rowIndex].high + mMarginPrimary; 1073 } else { 1074 if (mLastVisiblePos >= 0) { 1075 int lastRow = mGrid.getLocation(mLastVisiblePos).row; 1076 // if the last visible item is not last row, align to beginning, 1077 // otherwise start a new column after. 1078 if (lastRow < mNumRows - 1) { 1079 start = mRows[lastRow].low; 1080 } else { 1081 start = mRows[lastRow].high + mMarginPrimary; 1082 } 1083 } else { 1084 start = 0; 1085 } 1086 mRows[rowIndex].low = start; 1087 } 1088 end = start + length; 1089 mRows[rowIndex].high = end; 1090 } else { 1091 if (!rowIsEmpty) { 1092 // if there are existing item in the row, add margin between 1093 end = mRows[rowIndex].low - mMarginPrimary; 1094 start = end - length; 1095 } else { 1096 if (mFirstVisiblePos >= 0) { 1097 int firstRow = mGrid.getLocation(mFirstVisiblePos).row; 1098 // if the first visible item is not first row, align to beginning, 1099 // otherwise start a new column before. 1100 if (firstRow > 0) { 1101 start = mRows[firstRow].low; 1102 end = start + length; 1103 } else { 1104 end = mRows[firstRow].low - mMarginPrimary; 1105 start = end - length; 1106 } 1107 } else { 1108 start = 0; 1109 end = length; 1110 } 1111 mRows[rowIndex].high = end; 1112 } 1113 mRows[rowIndex].low = start; 1114 } 1115 if (mFirstVisiblePos < 0) { 1116 mFirstVisiblePos = mLastVisiblePos = index; 1117 } else { 1118 if (append) { 1119 mLastVisiblePos++; 1120 } else { 1121 mFirstVisiblePos--; 1122 } 1123 } 1124 if (DEBUG) Log.v(getTag(), "start " + start + " end " + end); 1125 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1126 layoutChild(rowIndex, v, start - mScrollOffsetPrimary, end - mScrollOffsetPrimary, 1127 startSecondary); 1128 if (DEBUG) { 1129 Log.d(getTag(), "addView " + index + " " + v); 1130 } 1131 if (index == mFirstVisiblePos) { 1132 updateScrollMin(); 1133 } 1134 if (index == mLastVisiblePos) { 1135 updateScrollMax(); 1136 } 1137 mChildrenStates.loadView(v, index); 1138 } 1139 }; 1140 1141 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1142 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1143 : v.getMeasuredWidth(); 1144 if (mFixedRowSizeSecondary > 0) { 1145 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1146 } 1147 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1148 final int horizontalGravity = mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1149 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1150 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1151 // do nothing 1152 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1153 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1154 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1155 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1156 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1157 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1158 } 1159 int left, top, right, bottom; 1160 if (mOrientation == HORIZONTAL) { 1161 left = start; 1162 top = startSecondary; 1163 right = end; 1164 bottom = startSecondary + sizeSecondary; 1165 } else { 1166 top = start; 1167 left = startSecondary; 1168 bottom = end; 1169 right = startSecondary + sizeSecondary; 1170 } 1171 v.layout(left, top, right, bottom); 1172 updateChildOpticalInsets(v, left, top, right, bottom); 1173 updateChildAlignments(v); 1174 } 1175 1176 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1177 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1178 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1179 v.getRight() - right, v.getBottom() - bottom); 1180 } 1181 1182 private void updateChildAlignments(View v) { 1183 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1184 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1185 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1186 } 1187 1188 private void updateChildAlignments() { 1189 for (int i = 0, c = getChildCount(); i < c; i++) { 1190 updateChildAlignments(getChildAt(i)); 1191 } 1192 } 1193 1194 private boolean needsAppendVisibleItem() { 1195 if (mLastVisiblePos < mFocusPosition) { 1196 return true; 1197 } 1198 int right = mScrollOffsetPrimary + mSizePrimary; 1199 for (int i = 0; i < mNumRows; i++) { 1200 if (mRows[i].low == mRows[i].high) { 1201 if (mRows[i].high < right) { 1202 return true; 1203 } 1204 } else if (mRows[i].high < right - mMarginPrimary) { 1205 return true; 1206 } 1207 } 1208 return false; 1209 } 1210 1211 private boolean needsPrependVisibleItem() { 1212 if (mFirstVisiblePos > mFocusPosition) { 1213 return true; 1214 } 1215 for (int i = 0; i < mNumRows; i++) { 1216 if (mRows[i].low == mRows[i].high) { 1217 if (mRows[i].low > mScrollOffsetPrimary) { 1218 return true; 1219 } 1220 } else if (mRows[i].low - mMarginPrimary > mScrollOffsetPrimary) { 1221 return true; 1222 } 1223 } 1224 return false; 1225 } 1226 1227 // Append one column if possible and return true if reach end. 1228 private boolean appendOneVisibleItem() { 1229 while (true) { 1230 if (mLastVisiblePos != NO_POSITION && mLastVisiblePos < mState.getItemCount() -1 && 1231 mLastVisiblePos < mGrid.getLastIndex()) { 1232 // append invisible view of saved location till last row 1233 final int index = mLastVisiblePos + 1; 1234 final int row = mGrid.getLocation(index).row; 1235 mGridProvider.createItem(index, row, true); 1236 if (row == mNumRows - 1) { 1237 return false; 1238 } 1239 } else if ((mLastVisiblePos == NO_POSITION && mState.getItemCount() > 0) || 1240 (mLastVisiblePos != NO_POSITION && 1241 mLastVisiblePos < mState.getItemCount() - 1)) { 1242 mGrid.appendItems(mScrollOffsetPrimary + mSizePrimary); 1243 return false; 1244 } else { 1245 return true; 1246 } 1247 } 1248 } 1249 1250 private void appendVisibleItems() { 1251 while (needsAppendVisibleItem()) { 1252 if (appendOneVisibleItem()) { 1253 break; 1254 } 1255 } 1256 } 1257 1258 // Prepend one column if possible and return true if reach end. 1259 private boolean prependOneVisibleItem() { 1260 while (true) { 1261 if (mFirstVisiblePos > 0) { 1262 if (mFirstVisiblePos > mGrid.getFirstIndex()) { 1263 // prepend invisible view of saved location till first row 1264 final int index = mFirstVisiblePos - 1; 1265 final int row = mGrid.getLocation(index).row; 1266 mGridProvider.createItem(index, row, false); 1267 if (row == 0) { 1268 return false; 1269 } 1270 } else { 1271 mGrid.prependItems(mScrollOffsetPrimary); 1272 return false; 1273 } 1274 } else { 1275 return true; 1276 } 1277 } 1278 } 1279 1280 private void prependVisibleItems() { 1281 while (needsPrependVisibleItem()) { 1282 if (prependOneVisibleItem()) { 1283 break; 1284 } 1285 } 1286 } 1287 1288 private void removeChildAt(int position) { 1289 View v = findViewByPosition(position); 1290 if (v != null) { 1291 if (DEBUG) { 1292 Log.d(getTag(), "removeAndRecycleViewAt " + position); 1293 } 1294 mChildrenStates.saveOffscreenView(v, position); 1295 removeAndRecycleView(v, mRecycler); 1296 } 1297 } 1298 1299 private void removeInvisibleViewsAtEnd() { 1300 if (!mPruneChild) { 1301 return; 1302 } 1303 boolean update = false; 1304 while(mLastVisiblePos > mFirstVisiblePos && mLastVisiblePos > mFocusPosition) { 1305 View view = findViewByPosition(mLastVisiblePos); 1306 if (getViewMin(view) > mSizePrimary) { 1307 removeChildAt(mLastVisiblePos); 1308 mLastVisiblePos--; 1309 update = true; 1310 } else { 1311 break; 1312 } 1313 } 1314 if (update) { 1315 updateRowsMinMax(); 1316 } 1317 } 1318 1319 private void removeInvisibleViewsAtFront() { 1320 if (!mPruneChild) { 1321 return; 1322 } 1323 boolean update = false; 1324 while(mLastVisiblePos > mFirstVisiblePos && mFirstVisiblePos < mFocusPosition) { 1325 View view = findViewByPosition(mFirstVisiblePos); 1326 if (getViewMax(view) < 0) { 1327 removeChildAt(mFirstVisiblePos); 1328 mFirstVisiblePos++; 1329 update = true; 1330 } else { 1331 break; 1332 } 1333 } 1334 if (update) { 1335 updateRowsMinMax(); 1336 } 1337 } 1338 1339 private void updateRowsMinMax() { 1340 if (mFirstVisiblePos < 0) { 1341 return; 1342 } 1343 for (int i = 0; i < mNumRows; i++) { 1344 mRows[i].low = Integer.MAX_VALUE; 1345 mRows[i].high = Integer.MIN_VALUE; 1346 } 1347 for (int i = mFirstVisiblePos; i <= mLastVisiblePos; i++) { 1348 View view = findViewByPosition(i); 1349 int row = mGrid.getLocation(i).row; 1350 int low = getViewMin(view) + mScrollOffsetPrimary; 1351 if (low < mRows[row].low) { 1352 mRows[row].low = low; 1353 } 1354 int high = getViewMax(view) + mScrollOffsetPrimary; 1355 if (high > mRows[row].high) { 1356 mRows[row].high = high; 1357 } 1358 } 1359 } 1360 1361 // Fast layout when there is no structure change, adapter change, etc. 1362 protected void fastRelayout(boolean scrollToFocus) { 1363 initScrollController(); 1364 1365 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 1366 1367 // relayout and repositioning views on each row 1368 for (int i = 0; i < mNumRows; i++) { 1369 List<Integer> row = rows[i]; 1370 final int startSecondary = getRowStartSecondary(i) - mScrollOffsetSecondary; 1371 for (int j = 0, size = row.size(); j < size; j++) { 1372 final int position = row.get(j); 1373 final View view = findViewByPosition(position); 1374 int primaryDelta, start, end; 1375 1376 if (mOrientation == HORIZONTAL) { 1377 final int primarySize = view.getMeasuredWidth(); 1378 if (view.isLayoutRequested()) { 1379 measureChild(view); 1380 } 1381 start = getViewMin(view); 1382 end = start + view.getMeasuredWidth(); 1383 primaryDelta = view.getMeasuredWidth() - primarySize; 1384 if (primaryDelta != 0) { 1385 for (int k = j + 1; k < size; k++) { 1386 findViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1387 } 1388 } 1389 } else { 1390 final int primarySize = view.getMeasuredHeight(); 1391 if (view.isLayoutRequested()) { 1392 measureChild(view); 1393 } 1394 start = getViewMin(view); 1395 end = start + view.getMeasuredHeight(); 1396 primaryDelta = view.getMeasuredHeight() - primarySize; 1397 if (primaryDelta != 0) { 1398 for (int k = j + 1; k < size; k++) { 1399 findViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1400 } 1401 } 1402 } 1403 layoutChild(i, view, start, end, startSecondary); 1404 } 1405 } 1406 1407 updateRowsMinMax(); 1408 appendVisibleItems(); 1409 prependVisibleItems(); 1410 1411 updateRowsMinMax(); 1412 updateScrollMin(); 1413 updateScrollMax(); 1414 updateScrollSecondAxis(); 1415 1416 if (scrollToFocus) { 1417 View focusView = findViewByPosition(mFocusPosition == NO_POSITION ? 0 : mFocusPosition); 1418 scrollToView(focusView, false); 1419 } 1420 } 1421 1422 public void removeAndRecycleAllViews(RecyclerView.Recycler recycler) { 1423 if (DEBUG) Log.v(TAG, "removeAndRecycleAllViews " + getChildCount()); 1424 for (int i = getChildCount() - 1; i >= 0; i--) { 1425 removeAndRecycleViewAt(i, recycler); 1426 } 1427 } 1428 1429 // Lays out items based on the current scroll position 1430 @Override 1431 public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) { 1432 if (DEBUG) { 1433 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1434 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1435 + " inPreLayout " + state.isPreLayout() 1436 + " didStructureChange " + state.didStructureChange() 1437 + " mForceFullLayout " + mForceFullLayout); 1438 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1439 } 1440 1441 if (mNumRows == 0) { 1442 // haven't done measure yet 1443 return; 1444 } 1445 final int itemCount = state.getItemCount(); 1446 if (itemCount < 0) { 1447 return; 1448 } 1449 1450 if (!mLayoutEnabled) { 1451 discardLayoutInfo(); 1452 removeAndRecycleAllViews(recycler); 1453 return; 1454 } 1455 mInLayout = true; 1456 1457 if (mLoadingState != null) { 1458 mFocusPosition = mLoadingState.index; 1459 mFocusPositionOffset = 0; 1460 mChildrenStates.getChildStates().putAll(mLoadingState.childStates); 1461 mLoadingState = null; 1462 } 1463 final boolean scrollToFocus = !isSmoothScrolling() 1464 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED; 1465 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1466 mFocusPosition = mFocusPosition + mFocusPositionOffset; 1467 mFocusPositionOffset = 0; 1468 } 1469 saveContext(recycler, state); 1470 // Track the old focus view so we can adjust our system scroll position 1471 // so that any scroll animations happening now will remain valid. 1472 // We must use same delta in Pre Layout (if prelayout exists) and second layout. 1473 // So we cache the deltas in PreLayout and use it in second layout. 1474 int delta = 0, deltaSecondary = 0; 1475 if (mFocusPosition != NO_POSITION && scrollToFocus) { 1476 // FIXME: we should get the remaining scroll animation offset from RecyclerView 1477 View focusView = findViewByPosition(mFocusPosition); 1478 if (focusView != null) { 1479 delta = mWindowAlignment.mainAxis().getSystemScrollPos(mScrollOffsetPrimary 1480 + getViewCenter(focusView), false, false) - mScrollOffsetPrimary; 1481 deltaSecondary = mWindowAlignment.secondAxis().getSystemScrollPos( 1482 mScrollOffsetSecondary + getViewCenterSecondary(focusView), 1483 false, false) - mScrollOffsetSecondary; 1484 } 1485 } 1486 1487 final boolean hasDoneFirstLayout = hasDoneFirstLayout(); 1488 int savedFocusPos = mFocusPosition; 1489 boolean fastRelayout = false; 1490 if (!mState.didStructureChange() && !mForceFullLayout && hasDoneFirstLayout) { 1491 fastRelayout = true; 1492 fastRelayout(scrollToFocus); 1493 } else { 1494 boolean hadFocus = mBaseGridView.hasFocus(); 1495 1496 int newFocusPosition = init(mFocusPosition); 1497 if (DEBUG) { 1498 Log.v(getTag(), "mFocusPosition " + mFocusPosition + " newFocusPosition " 1499 + newFocusPosition); 1500 } 1501 1502 mWindowAlignment.mainAxis().invalidateScrollMin(); 1503 mWindowAlignment.mainAxis().invalidateScrollMax(); 1504 // depending on result of init(), either recreating everything 1505 // or try to reuse the row start positions near mFocusPosition 1506 if (mGrid.getSize() == 0) { 1507 // this is a fresh creating all items, starting from 1508 // mFocusPosition with a estimated row index. 1509 mGrid.setStart(newFocusPosition, StaggeredGrid.START_DEFAULT); 1510 1511 // Can't track the old focus view 1512 delta = deltaSecondary = 0; 1513 1514 } else { 1515 // mGrid remembers Locations for the column that 1516 // contains mFocusePosition and also mRows remembers start 1517 // positions of each row. 1518 // Manually re-create child views for that column 1519 int firstIndex = mGrid.getFirstIndex(); 1520 int lastIndex = mGrid.getLastIndex(); 1521 for (int i = firstIndex; i <= lastIndex; i++) { 1522 mGridProvider.createItem(i, mGrid.getLocation(i).row, true); 1523 } 1524 } 1525 // add visible views at end until reach the end of window 1526 appendVisibleItems(); 1527 // add visible views at front until reach the start of window 1528 prependVisibleItems(); 1529 // multiple rounds: scrollToView of first round may drag first/last child into 1530 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1531 int oldFirstVisible; 1532 int oldLastVisible; 1533 do { 1534 updateScrollMin(); 1535 updateScrollMax(); 1536 oldFirstVisible = mFirstVisiblePos; 1537 oldLastVisible = mLastVisiblePos; 1538 View focusView = findViewByPosition(newFocusPosition); 1539 // we need force to initialize the child view's position 1540 scrollToView(focusView, false); 1541 if (focusView != null && hadFocus) { 1542 focusView.requestFocus(); 1543 } 1544 appendVisibleItems(); 1545 prependVisibleItems(); 1546 removeInvisibleViewsAtFront(); 1547 removeInvisibleViewsAtEnd(); 1548 } while (mFirstVisiblePos != oldFirstVisible || mLastVisiblePos != oldLastVisible); 1549 } 1550 mForceFullLayout = false; 1551 1552 if (scrollToFocus) { 1553 scrollDirectionPrimary(-delta); 1554 scrollDirectionSecondary(-deltaSecondary); 1555 } 1556 appendVisibleItems(); 1557 prependVisibleItems(); 1558 removeInvisibleViewsAtFront(); 1559 removeInvisibleViewsAtEnd(); 1560 1561 if (DEBUG) { 1562 StringWriter sw = new StringWriter(); 1563 PrintWriter pw = new PrintWriter(sw); 1564 mGrid.debugPrint(pw); 1565 Log.d(getTag(), sw.toString()); 1566 } 1567 1568 if (mRowSecondarySizeRefresh) { 1569 mRowSecondarySizeRefresh = false; 1570 } else { 1571 updateRowSecondarySizeRefresh(); 1572 } 1573 1574 if (!fastRelayout || mFocusPosition != savedFocusPos) { 1575 dispatchChildSelected(); 1576 } 1577 mInLayout = false; 1578 leaveContext(); 1579 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1580 } 1581 1582 private void offsetChildrenSecondary(int increment) { 1583 final int childCount = getChildCount(); 1584 if (mOrientation == HORIZONTAL) { 1585 for (int i = 0; i < childCount; i++) { 1586 getChildAt(i).offsetTopAndBottom(increment); 1587 } 1588 } else { 1589 for (int i = 0; i < childCount; i++) { 1590 getChildAt(i).offsetLeftAndRight(increment); 1591 } 1592 } 1593 } 1594 1595 private void offsetChildrenPrimary(int increment) { 1596 final int childCount = getChildCount(); 1597 if (mOrientation == VERTICAL) { 1598 for (int i = 0; i < childCount; i++) { 1599 getChildAt(i).offsetTopAndBottom(increment); 1600 } 1601 } else { 1602 for (int i = 0; i < childCount; i++) { 1603 getChildAt(i).offsetLeftAndRight(increment); 1604 } 1605 } 1606 } 1607 1608 @Override 1609 public int scrollHorizontallyBy(int dx, Recycler recycler, RecyclerView.State state) { 1610 if (DEBUG) Log.v(getTag(), "scrollHorizontallyBy " + dx); 1611 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1612 return 0; 1613 } 1614 saveContext(recycler, state); 1615 int result; 1616 if (mOrientation == HORIZONTAL) { 1617 result = scrollDirectionPrimary(dx); 1618 } else { 1619 result = scrollDirectionSecondary(dx); 1620 } 1621 leaveContext(); 1622 return result; 1623 } 1624 1625 @Override 1626 public int scrollVerticallyBy(int dy, Recycler recycler, RecyclerView.State state) { 1627 if (DEBUG) Log.v(getTag(), "scrollVerticallyBy " + dy); 1628 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1629 return 0; 1630 } 1631 saveContext(recycler, state); 1632 int result; 1633 if (mOrientation == VERTICAL) { 1634 result = scrollDirectionPrimary(dy); 1635 } else { 1636 result = scrollDirectionSecondary(dy); 1637 } 1638 leaveContext(); 1639 return result; 1640 } 1641 1642 // scroll in main direction may add/prune views 1643 private int scrollDirectionPrimary(int da) { 1644 if (da > 0) { 1645 if (!mWindowAlignment.mainAxis().isMaxUnknown()) { 1646 int maxScroll = mWindowAlignment.mainAxis().getMaxScroll(); 1647 if (mScrollOffsetPrimary + da > maxScroll) { 1648 da = maxScroll - mScrollOffsetPrimary; 1649 } 1650 } 1651 } else if (da < 0) { 1652 if (!mWindowAlignment.mainAxis().isMinUnknown()) { 1653 int minScroll = mWindowAlignment.mainAxis().getMinScroll(); 1654 if (mScrollOffsetPrimary + da < minScroll) { 1655 da = minScroll - mScrollOffsetPrimary; 1656 } 1657 } 1658 } 1659 if (da == 0) { 1660 return 0; 1661 } 1662 offsetChildrenPrimary(-da); 1663 mScrollOffsetPrimary += da; 1664 if (mInLayout) { 1665 return da; 1666 } 1667 1668 int childCount = getChildCount(); 1669 boolean updated; 1670 1671 if (da > 0) { 1672 appendVisibleItems(); 1673 } else if (da < 0) { 1674 prependVisibleItems(); 1675 } 1676 updated = getChildCount() > childCount; 1677 childCount = getChildCount(); 1678 1679 if (da > 0) { 1680 removeInvisibleViewsAtFront(); 1681 } else if (da < 0) { 1682 removeInvisibleViewsAtEnd(); 1683 } 1684 updated |= getChildCount() < childCount; 1685 1686 if (updated) { 1687 updateRowSecondarySizeRefresh(); 1688 } 1689 1690 mBaseGridView.invalidate(); 1691 return da; 1692 } 1693 1694 // scroll in second direction will not add/prune views 1695 private int scrollDirectionSecondary(int dy) { 1696 if (dy == 0) { 1697 return 0; 1698 } 1699 offsetChildrenSecondary(-dy); 1700 mScrollOffsetSecondary += dy; 1701 mBaseGridView.invalidate(); 1702 return dy; 1703 } 1704 1705 private void updateScrollMax() { 1706 if (mLastVisiblePos < 0) { 1707 return; 1708 } 1709 final boolean lastAvailable = mLastVisiblePos == mState.getItemCount() - 1; 1710 final boolean maxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1711 if (!lastAvailable && maxUnknown) { 1712 return; 1713 } 1714 int maxEdge = Integer.MIN_VALUE; 1715 int rowIndex = -1; 1716 for (int i = 0; i < mRows.length; i++) { 1717 if (mRows[i].high > maxEdge) { 1718 maxEdge = mRows[i].high; 1719 rowIndex = i; 1720 } 1721 } 1722 int maxScroll = Integer.MAX_VALUE; 1723 for (int i = mLastVisiblePos; i >= mFirstVisiblePos; i--) { 1724 StaggeredGrid.Location location = mGrid.getLocation(i); 1725 if (location != null && location.row == rowIndex) { 1726 int savedMaxEdge = mWindowAlignment.mainAxis().getMaxEdge(); 1727 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1728 maxScroll = getPrimarySystemScrollPosition(findViewByPosition(i)); 1729 mWindowAlignment.mainAxis().setMaxEdge(savedMaxEdge); 1730 break; 1731 } 1732 } 1733 if (lastAvailable) { 1734 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1735 mWindowAlignment.mainAxis().setMaxScroll(maxScroll); 1736 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge + 1737 " scrollMax to " + maxScroll); 1738 } else { 1739 // the maxScroll for currently last visible item is larger, 1740 // so we must invalidate the max scroll value. 1741 if (maxScroll > mWindowAlignment.mainAxis().getMaxScroll()) { 1742 mWindowAlignment.mainAxis().invalidateScrollMax(); 1743 if (DEBUG) Log.v(getTag(), "Invalidate scrollMax since it should be " 1744 + "greater than " + maxScroll); 1745 } 1746 } 1747 } 1748 1749 private void updateScrollMin() { 1750 if (mFirstVisiblePos < 0) { 1751 return; 1752 } 1753 final boolean firstAvailable = mFirstVisiblePos == 0; 1754 final boolean minUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1755 if (!firstAvailable && minUnknown) { 1756 return; 1757 } 1758 int minEdge = Integer.MAX_VALUE; 1759 int rowIndex = -1; 1760 for (int i = 0; i < mRows.length; i++) { 1761 if (mRows[i].low < minEdge) { 1762 minEdge = mRows[i].low; 1763 rowIndex = i; 1764 } 1765 } 1766 int minScroll = Integer.MIN_VALUE; 1767 for (int i = mFirstVisiblePos; i <= mLastVisiblePos; i++) { 1768 StaggeredGrid.Location location = mGrid.getLocation(i); 1769 if (location != null && location.row == rowIndex) { 1770 int savedMinEdge = mWindowAlignment.mainAxis().getMinEdge(); 1771 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1772 minScroll = getPrimarySystemScrollPosition(findViewByPosition(i)); 1773 mWindowAlignment.mainAxis().setMinEdge(savedMinEdge); 1774 break; 1775 } 1776 } 1777 if (firstAvailable) { 1778 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1779 mWindowAlignment.mainAxis().setMinScroll(minScroll); 1780 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge + 1781 " scrollMin to " + minScroll); 1782 } else { 1783 // the minScroll for currently first visible item is smaller, 1784 // so we must invalidate the min scroll value. 1785 if (minScroll < mWindowAlignment.mainAxis().getMinScroll()) { 1786 mWindowAlignment.mainAxis().invalidateScrollMin(); 1787 if (DEBUG) Log.v(getTag(), "Invalidate scrollMin, since it should be " 1788 + "less than " + minScroll); 1789 } 1790 } 1791 } 1792 1793 private void updateScrollSecondAxis() { 1794 mWindowAlignment.secondAxis().setMinEdge(0); 1795 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1796 } 1797 1798 private void initScrollController() { 1799 // mScrollOffsetPrimary and mScrollOffsetSecondary includes the padding. 1800 // e.g. when topPadding is 16 for horizontal grid view, the initial 1801 // mScrollOffsetSecondary is -16. fastLayout() put views based on offsets(not padding), 1802 // when padding changes to 20, we also need update mScrollOffsetSecondary to -20 before 1803 // fastLayout() is performed 1804 int paddingPrimaryDiff, paddingSecondaryDiff; 1805 if (mOrientation == HORIZONTAL) { 1806 paddingPrimaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1807 paddingSecondaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1808 } else { 1809 paddingPrimaryDiff = getPaddingTop() - mWindowAlignment.vertical.getPaddingLow(); 1810 paddingSecondaryDiff = getPaddingLeft() - mWindowAlignment.horizontal.getPaddingLow(); 1811 } 1812 mScrollOffsetPrimary -= paddingPrimaryDiff; 1813 mScrollOffsetSecondary -= paddingSecondaryDiff; 1814 1815 mWindowAlignment.horizontal.setSize(getWidth()); 1816 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1817 mWindowAlignment.vertical.setSize(getHeight()); 1818 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1819 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1820 1821 if (DEBUG) { 1822 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1823 + " mWindowAlignment " + mWindowAlignment); 1824 } 1825 } 1826 1827 public void setSelection(RecyclerView parent, int position) { 1828 setSelection(parent, position, false); 1829 } 1830 1831 public void setSelectionSmooth(RecyclerView parent, int position) { 1832 setSelection(parent, position, true); 1833 } 1834 1835 public int getSelection() { 1836 return mFocusPosition; 1837 } 1838 1839 public void setSelection(RecyclerView parent, int position, boolean smooth) { 1840 if (mFocusPosition == position) { 1841 return; 1842 } 1843 View view = findViewByPosition(position); 1844 if (view != null) { 1845 mInSelection = true; 1846 scrollToView(view, smooth); 1847 mInSelection = false; 1848 } else { 1849 mFocusPosition = position; 1850 mFocusPositionOffset = 0; 1851 if (!mLayoutEnabled) { 1852 return; 1853 } 1854 if (smooth) { 1855 if (!hasDoneFirstLayout()) { 1856 Log.w(getTag(), "setSelectionSmooth should " + 1857 "not be called before first layout pass"); 1858 return; 1859 } 1860 LinearSmoothScroller linearSmoothScroller = 1861 new LinearSmoothScroller(parent.getContext()) { 1862 @Override 1863 public PointF computeScrollVectorForPosition(int targetPosition) { 1864 if (getChildCount() == 0) { 1865 return null; 1866 } 1867 final int firstChildPos = getPosition(getChildAt(0)); 1868 final int direction = targetPosition < firstChildPos ? -1 : 1; 1869 if (mOrientation == HORIZONTAL) { 1870 return new PointF(direction, 0); 1871 } else { 1872 return new PointF(0, direction); 1873 } 1874 } 1875 @Override 1876 protected void onTargetFound(View targetView, 1877 RecyclerView.State state, Action action) { 1878 if (hasFocus()) { 1879 targetView.requestFocus(); 1880 } 1881 dispatchChildSelected(); 1882 if (getScrollPosition(targetView, mTempDeltas)) { 1883 int dx, dy; 1884 if (mOrientation == HORIZONTAL) { 1885 dx = mTempDeltas[0]; 1886 dy = mTempDeltas[1]; 1887 } else { 1888 dx = mTempDeltas[1]; 1889 dy = mTempDeltas[0]; 1890 } 1891 final int distance = (int) Math.sqrt(dx * dx + dy * dy); 1892 final int time = calculateTimeForDeceleration(distance); 1893 action.update(dx, dy, time, mDecelerateInterpolator); 1894 } 1895 } 1896 }; 1897 linearSmoothScroller.setTargetPosition(position); 1898 startSmoothScroll(linearSmoothScroller); 1899 } else { 1900 mForceFullLayout = true; 1901 parent.requestLayout(); 1902 } 1903 } 1904 } 1905 1906 @Override 1907 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 1908 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1909 int pos = mFocusPosition + mFocusPositionOffset; 1910 if (positionStart <= pos) { 1911 mFocusPositionOffset += itemCount; 1912 } 1913 } 1914 } 1915 1916 @Override 1917 public void onItemsChanged(RecyclerView recyclerView) { 1918 mFocusPositionOffset = 0; 1919 mChildrenStates.clear(); 1920 } 1921 1922 @Override 1923 public void onItemsRemoved(RecyclerView recyclerView, int positionStart, int itemCount) { 1924 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1925 int pos = mFocusPosition + mFocusPositionOffset; 1926 if (positionStart <= pos) { 1927 if (positionStart + itemCount > pos) { 1928 // stop updating offset after the focus item was removed 1929 mFocusPositionOffset = Integer.MIN_VALUE; 1930 } else { 1931 mFocusPositionOffset -= itemCount; 1932 } 1933 } 1934 } 1935 for (int i = 0; i < itemCount; i++) { 1936 mChildrenStates.remove(positionStart + i); 1937 } 1938 } 1939 1940 public void onItemsMoved(RecyclerView recyclerView, int fromPosition, int toPosition, 1941 int itemCount) { 1942 if (mFocusPosition != NO_POSITION && mFocusPositionOffset != Integer.MIN_VALUE) { 1943 int pos = mFocusPosition + mFocusPositionOffset; 1944 if (fromPosition <= pos && pos < fromPosition + itemCount) { 1945 // moved items include focused position 1946 mFocusPositionOffset += toPosition - fromPosition; 1947 } else if (fromPosition < pos && toPosition > pos - itemCount) { 1948 // move items before focus position to after focused position 1949 mFocusPositionOffset -= itemCount; 1950 } else if (fromPosition > pos && toPosition < pos) { 1951 // move items after focus position to before focused position 1952 mFocusPositionOffset += itemCount; 1953 } 1954 } 1955 } 1956 1957 @Override 1958 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 1959 if (mFocusSearchDisabled) { 1960 return true; 1961 } 1962 if (!mInLayout && !mInSelection) { 1963 scrollToView(child, true); 1964 } 1965 return true; 1966 } 1967 1968 @Override 1969 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 1970 boolean immediate) { 1971 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 1972 return false; 1973 } 1974 1975 int getScrollOffsetX() { 1976 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 1977 } 1978 1979 int getScrollOffsetY() { 1980 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 1981 } 1982 1983 public void getViewSelectedOffsets(View view, int[] offsets) { 1984 if (mOrientation == HORIZONTAL) { 1985 offsets[0] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 1986 offsets[1] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 1987 } else { 1988 offsets[1] = getPrimarySystemScrollPosition(view) - mScrollOffsetPrimary; 1989 offsets[0] = getSecondarySystemScrollPosition(view) - mScrollOffsetSecondary; 1990 } 1991 } 1992 1993 private int getPrimarySystemScrollPosition(View view) { 1994 int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 1995 int pos = getPositionByView(view); 1996 StaggeredGrid.Location location = mGrid.getLocation(pos); 1997 final int row = location.row; 1998 boolean isFirst = mFirstVisiblePos == 0; 1999 // TODO: change to use State object in onRequestChildFocus() 2000 boolean isLast = mLastVisiblePos == (mState == null ? 2001 getItemCount() : mState.getItemCount()) - 1; 2002 if (isFirst || isLast) { 2003 for (int i = getChildCount() - 1; i >= 0; i--) { 2004 int position = getPositionByIndex(i); 2005 StaggeredGrid.Location loc = mGrid.getLocation(position); 2006 if (loc != null && loc.row == row) { 2007 if (position < pos) { 2008 isFirst = false; 2009 } else if (position > pos) { 2010 isLast = false; 2011 } 2012 } 2013 } 2014 } 2015 return mWindowAlignment.mainAxis().getSystemScrollPos(viewCenterPrimary, isFirst, isLast); 2016 } 2017 2018 private int getSecondarySystemScrollPosition(View view) { 2019 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 2020 int pos = getPositionByView(view); 2021 StaggeredGrid.Location location = mGrid.getLocation(pos); 2022 final int row = location.row; 2023 boolean isFirst = row == 0; 2024 boolean isLast = row == mGrid.getNumRows() - 1; 2025 return mWindowAlignment.secondAxis().getSystemScrollPos(viewCenterSecondary, 2026 isFirst, isLast); 2027 } 2028 2029 /** 2030 * Scroll to a given child view and change mFocusPosition. 2031 */ 2032 private void scrollToView(View view, boolean smooth) { 2033 int newFocusPosition = getPositionByView(view); 2034 if (newFocusPosition != mFocusPosition) { 2035 mFocusPosition = newFocusPosition; 2036 mFocusPositionOffset = 0; 2037 if (!mInLayout) { 2038 dispatchChildSelected(); 2039 } 2040 } 2041 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 2042 mBaseGridView.invalidate(); 2043 } 2044 if (view == null) { 2045 return; 2046 } 2047 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 2048 // transfer focus to the child if it does not have focus yet (e.g. triggered 2049 // by setSelection()) 2050 view.requestFocus(); 2051 } 2052 if (!mScrollEnabled) { 2053 return; 2054 } 2055 if (getScrollPosition(view, mTempDeltas)) { 2056 scrollGrid(mTempDeltas[0], mTempDeltas[1], smooth); 2057 } 2058 } 2059 2060 private boolean getScrollPosition(View view, int[] deltas) { 2061 switch (mFocusScrollStrategy) { 2062 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2063 default: 2064 return getAlignedPosition(view, deltas); 2065 case BaseGridView.FOCUS_SCROLL_ITEM: 2066 case BaseGridView.FOCUS_SCROLL_PAGE: 2067 return getNoneAlignedPosition(view, deltas); 2068 } 2069 } 2070 2071 private boolean getNoneAlignedPosition(View view, int[] deltas) { 2072 int pos = getPositionByView(view); 2073 int viewMin = getViewMin(view); 2074 int viewMax = getViewMax(view); 2075 // we either align "firstView" to left/top padding edge 2076 // or align "lastView" to right/bottom padding edge 2077 View firstView = null; 2078 View lastView = null; 2079 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 2080 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 2081 final int row = mGrid.getLocation(pos).row; 2082 if (viewMin < paddingLow) { 2083 // view enters low padding area: 2084 firstView = view; 2085 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2086 // scroll one "page" left/top, 2087 // align first visible item of the "page" at the low padding edge. 2088 while (!prependOneVisibleItem()) { 2089 List<Integer> positions = 2090 mGrid.getItemPositionsInRows(mFirstVisiblePos, pos)[row]; 2091 firstView = findViewByPosition(positions.get(0)); 2092 if (viewMax - getViewMin(firstView) > clientSize) { 2093 if (positions.size() > 1) { 2094 firstView = findViewByPosition(positions.get(1)); 2095 } 2096 break; 2097 } 2098 } 2099 } 2100 } else if (viewMax > clientSize + paddingLow) { 2101 // view enters high padding area: 2102 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 2103 // scroll whole one page right/bottom, align view at the low padding edge. 2104 firstView = view; 2105 do { 2106 List<Integer> positions = 2107 mGrid.getItemPositionsInRows(pos, mLastVisiblePos)[row]; 2108 lastView = findViewByPosition(positions.get(positions.size() - 1)); 2109 if (getViewMax(lastView) - viewMin > clientSize) { 2110 lastView = null; 2111 break; 2112 } 2113 } while (!appendOneVisibleItem()); 2114 if (lastView != null) { 2115 // however if we reached end, we should align last view. 2116 firstView = null; 2117 } 2118 } else { 2119 lastView = view; 2120 } 2121 } 2122 int scrollPrimary = 0; 2123 int scrollSecondary = 0; 2124 if (firstView != null) { 2125 scrollPrimary = getViewMin(firstView) - paddingLow; 2126 } else if (lastView != null) { 2127 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 2128 } 2129 View secondaryAlignedView; 2130 if (firstView != null) { 2131 secondaryAlignedView = firstView; 2132 } else if (lastView != null) { 2133 secondaryAlignedView = lastView; 2134 } else { 2135 secondaryAlignedView = view; 2136 } 2137 scrollSecondary = getSecondarySystemScrollPosition(secondaryAlignedView); 2138 scrollSecondary -= mScrollOffsetSecondary; 2139 if (scrollPrimary != 0 || scrollSecondary != 0) { 2140 deltas[0] = scrollPrimary; 2141 deltas[1] = scrollSecondary; 2142 return true; 2143 } 2144 return false; 2145 } 2146 2147 private boolean getAlignedPosition(View view, int[] deltas) { 2148 int scrollPrimary = getPrimarySystemScrollPosition(view); 2149 int scrollSecondary = getSecondarySystemScrollPosition(view); 2150 if (DEBUG) { 2151 Log.v(getTag(), "getAlignedPosition " + scrollPrimary + " " + scrollSecondary 2152 +" " + mWindowAlignment); 2153 } 2154 scrollPrimary -= mScrollOffsetPrimary; 2155 scrollSecondary -= mScrollOffsetSecondary; 2156 if (scrollPrimary != 0 || scrollSecondary != 0) { 2157 deltas[0] = scrollPrimary; 2158 deltas[1] = scrollSecondary; 2159 return true; 2160 } 2161 return false; 2162 } 2163 2164 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 2165 if (mInLayout) { 2166 scrollDirectionPrimary(scrollPrimary); 2167 scrollDirectionSecondary(scrollSecondary); 2168 } else { 2169 int scrollX; 2170 int scrollY; 2171 if (mOrientation == HORIZONTAL) { 2172 scrollX = scrollPrimary; 2173 scrollY = scrollSecondary; 2174 } else { 2175 scrollX = scrollSecondary; 2176 scrollY = scrollPrimary; 2177 } 2178 if (smooth) { 2179 mBaseGridView.smoothScrollBy(scrollX, scrollY); 2180 } else { 2181 mBaseGridView.scrollBy(scrollX, scrollY); 2182 } 2183 } 2184 } 2185 2186 public void setPruneChild(boolean pruneChild) { 2187 if (mPruneChild != pruneChild) { 2188 mPruneChild = pruneChild; 2189 if (mPruneChild) { 2190 requestLayout(); 2191 } 2192 } 2193 } 2194 2195 public boolean getPruneChild() { 2196 return mPruneChild; 2197 } 2198 2199 public void setScrollEnabled(boolean scrollEnabled) { 2200 if (mScrollEnabled != scrollEnabled) { 2201 mScrollEnabled = scrollEnabled; 2202 if (mScrollEnabled && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 2203 View focusView = findViewByPosition(mFocusPosition == NO_POSITION ? 0 : 2204 mFocusPosition); 2205 if (focusView != null) { 2206 scrollToView(focusView, true); 2207 } 2208 } 2209 } 2210 } 2211 2212 public boolean isScrollEnabled() { 2213 return mScrollEnabled; 2214 } 2215 2216 private int findImmediateChildIndex(View view) { 2217 while (view != null && view != mBaseGridView) { 2218 int index = mBaseGridView.indexOfChild(view); 2219 if (index >= 0) { 2220 return index; 2221 } 2222 view = (View) view.getParent(); 2223 } 2224 return NO_POSITION; 2225 } 2226 2227 void setFocusSearchDisabled(boolean disabled) { 2228 mFocusSearchDisabled = disabled; 2229 } 2230 2231 boolean isFocusSearchDisabled() { 2232 return mFocusSearchDisabled; 2233 } 2234 2235 @Override 2236 public View onInterceptFocusSearch(View focused, int direction) { 2237 if (mFocusSearchDisabled) { 2238 return focused; 2239 } 2240 return null; 2241 } 2242 2243 boolean hasPreviousViewInSameRow(int pos) { 2244 if (mGrid == null || pos == NO_POSITION) { 2245 return false; 2246 } 2247 if (mFirstVisiblePos > 0) { 2248 return true; 2249 } 2250 final int focusedRow = mGrid.getLocation(pos).row; 2251 for (int i = getChildCount() - 1; i >= 0; i--) { 2252 int position = getPositionByIndex(i); 2253 StaggeredGrid.Location loc = mGrid.getLocation(position); 2254 if (loc != null && loc.row == focusedRow) { 2255 if (position < pos) { 2256 return true; 2257 } 2258 } 2259 } 2260 return false; 2261 } 2262 2263 @Override 2264 public boolean onAddFocusables(RecyclerView recyclerView, 2265 ArrayList<View> views, int direction, int focusableMode) { 2266 if (mFocusSearchDisabled) { 2267 return true; 2268 } 2269 // If this viewgroup or one of its children currently has focus then we 2270 // consider our children for focus searching in main direction on the same row. 2271 // If this viewgroup has no focus and using focus align, we want the system 2272 // to ignore our children and pass focus to the viewgroup, which will pass 2273 // focus on to its children appropriately. 2274 // If this viewgroup has no focus and not using focus align, we want to 2275 // consider the child that does not overlap with padding area. 2276 if (recyclerView.hasFocus()) { 2277 final int movement = getMovement(direction); 2278 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2279 // Move on secondary direction uses default addFocusables(). 2280 return false; 2281 } 2282 final View focused = recyclerView.findFocus(); 2283 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2284 // Add focusables of focused item. 2285 if (focusedPos != NO_POSITION) { 2286 findViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2287 } 2288 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2289 mGrid.getLocation(focusedPos).row : NO_POSITION; 2290 // Add focusables of next neighbor of same row on the focus search direction. 2291 if (mGrid != null) { 2292 final int focusableCount = views.size(); 2293 for (int i = 0, count = getChildCount(); i < count; i++) { 2294 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2295 final View child = getChildAt(index); 2296 if (child.getVisibility() != View.VISIBLE) { 2297 continue; 2298 } 2299 int position = getPositionByIndex(index); 2300 StaggeredGrid.Location loc = mGrid.getLocation(position); 2301 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2302 if (focusedPos == NO_POSITION || 2303 (movement == NEXT_ITEM && position > focusedPos) 2304 || (movement == PREV_ITEM && position < focusedPos)) { 2305 child.addFocusables(views, direction, focusableMode); 2306 if (views.size() > focusableCount) { 2307 break; 2308 } 2309 } 2310 } 2311 } 2312 } 2313 } else { 2314 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2315 // adding views not overlapping padding area to avoid scrolling in gaining focus 2316 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2317 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2318 int focusableCount = views.size(); 2319 for (int i = 0, count = getChildCount(); i < count; i++) { 2320 View child = getChildAt(i); 2321 if (child.getVisibility() == View.VISIBLE) { 2322 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2323 child.addFocusables(views, direction, focusableMode); 2324 } 2325 } 2326 } 2327 // if we cannot find any, then just add all children. 2328 if (views.size() == focusableCount) { 2329 for (int i = 0, count = getChildCount(); i < count; i++) { 2330 View child = getChildAt(i); 2331 if (child.getVisibility() == View.VISIBLE) { 2332 child.addFocusables(views, direction, focusableMode); 2333 } 2334 } 2335 if (views.size() != focusableCount) { 2336 return true; 2337 } 2338 } else { 2339 return true; 2340 } 2341 // if still cannot find any, fall through and add itself 2342 } 2343 if (recyclerView.isFocusable()) { 2344 views.add(recyclerView); 2345 } 2346 } 2347 return true; 2348 } 2349 2350 @Override 2351 public View onFocusSearchFailed(View focused, int direction, Recycler recycler, 2352 RecyclerView.State state) { 2353 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2354 2355 View view = null; 2356 int movement = getMovement(direction); 2357 if (mNumRows == 1) { 2358 // for simple row, use LinearSmoothScroller to smooth animation. 2359 // It will stay at a fixed cap speed in continuous scroll. 2360 if (movement == NEXT_ITEM) { 2361 int newPos = mFocusPosition + mNumRows; 2362 if (newPos < getItemCount()) { 2363 setSelectionSmooth(mBaseGridView, newPos); 2364 view = focused; 2365 } else { 2366 if (!mFocusOutEnd) { 2367 view = focused; 2368 } 2369 } 2370 } else if (movement == PREV_ITEM){ 2371 int newPos = mFocusPosition - mNumRows; 2372 if (newPos >= 0) { 2373 setSelectionSmooth(mBaseGridView, newPos); 2374 view = focused; 2375 } else { 2376 if (!mFocusOutFront) { 2377 view = focused; 2378 } 2379 } 2380 } 2381 } else if (mNumRows > 1) { 2382 // for possible staggered grid, we need guarantee focus to same row/column. 2383 // TODO: we may also use LinearSmoothScroller. 2384 saveContext(recycler, state); 2385 final FocusFinder ff = FocusFinder.getInstance(); 2386 if (movement == NEXT_ITEM) { 2387 while (view == null && !appendOneVisibleItem()) { 2388 view = ff.findNextFocus(mBaseGridView, focused, direction); 2389 } 2390 } else if (movement == PREV_ITEM){ 2391 while (view == null && !prependOneVisibleItem()) { 2392 view = ff.findNextFocus(mBaseGridView, focused, direction); 2393 } 2394 } 2395 if (view == null) { 2396 // returning the same view to prevent focus lost when scrolling past the end of the list 2397 if (movement == PREV_ITEM) { 2398 view = mFocusOutFront ? null : focused; 2399 } else if (movement == NEXT_ITEM){ 2400 view = mFocusOutEnd ? null : focused; 2401 } 2402 } 2403 leaveContext(); 2404 } 2405 if (DEBUG) Log.v(getTag(), "returning view " + view); 2406 return view; 2407 } 2408 2409 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2410 Rect previouslyFocusedRect) { 2411 switch (mFocusScrollStrategy) { 2412 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2413 default: 2414 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2415 direction, previouslyFocusedRect); 2416 case BaseGridView.FOCUS_SCROLL_PAGE: 2417 case BaseGridView.FOCUS_SCROLL_ITEM: 2418 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2419 direction, previouslyFocusedRect); 2420 } 2421 } 2422 2423 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2424 int direction, Rect previouslyFocusedRect) { 2425 View view = findViewByPosition(mFocusPosition); 2426 if (view != null) { 2427 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2428 if (!result && DEBUG) { 2429 Log.w(getTag(), "failed to request focus on " + view); 2430 } 2431 return result; 2432 } 2433 return false; 2434 } 2435 2436 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2437 int direction, Rect previouslyFocusedRect) { 2438 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2439 int index; 2440 int increment; 2441 int end; 2442 int count = getChildCount(); 2443 if ((direction & View.FOCUS_FORWARD) != 0) { 2444 index = 0; 2445 increment = 1; 2446 end = count; 2447 } else { 2448 index = count - 1; 2449 increment = -1; 2450 end = -1; 2451 } 2452 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2453 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2454 for (int i = index; i != end; i += increment) { 2455 View child = getChildAt(i); 2456 if (child.getVisibility() == View.VISIBLE) { 2457 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2458 if (child.requestFocus(direction, previouslyFocusedRect)) { 2459 return true; 2460 } 2461 } 2462 } 2463 } 2464 return false; 2465 } 2466 2467 private final static int PREV_ITEM = 0; 2468 private final static int NEXT_ITEM = 1; 2469 private final static int PREV_ROW = 2; 2470 private final static int NEXT_ROW = 3; 2471 2472 private int getMovement(int direction) { 2473 int movement = View.FOCUS_LEFT; 2474 2475 if (mOrientation == HORIZONTAL) { 2476 switch(direction) { 2477 case View.FOCUS_LEFT: 2478 movement = PREV_ITEM; 2479 break; 2480 case View.FOCUS_RIGHT: 2481 movement = NEXT_ITEM; 2482 break; 2483 case View.FOCUS_UP: 2484 movement = PREV_ROW; 2485 break; 2486 case View.FOCUS_DOWN: 2487 movement = NEXT_ROW; 2488 break; 2489 } 2490 } else if (mOrientation == VERTICAL) { 2491 switch(direction) { 2492 case View.FOCUS_LEFT: 2493 movement = PREV_ROW; 2494 break; 2495 case View.FOCUS_RIGHT: 2496 movement = NEXT_ROW; 2497 break; 2498 case View.FOCUS_UP: 2499 movement = PREV_ITEM; 2500 break; 2501 case View.FOCUS_DOWN: 2502 movement = NEXT_ITEM; 2503 break; 2504 } 2505 } 2506 2507 return movement; 2508 } 2509 2510 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2511 View view = findViewByPosition(mFocusPosition); 2512 if (view == null) { 2513 return i; 2514 } 2515 int focusIndex = recyclerView.indexOfChild(view); 2516 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2517 // drawing order is 0 1 2 3 9 8 7 6 5 4 2518 if (i < focusIndex) { 2519 return i; 2520 } else if (i < childCount - 1) { 2521 return focusIndex + childCount - 1 - i; 2522 } else { 2523 return focusIndex; 2524 } 2525 } 2526 2527 @Override 2528 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2529 RecyclerView.Adapter newAdapter) { 2530 discardLayoutInfo(); 2531 mFocusPosition = NO_POSITION; 2532 mFocusPositionOffset = 0; 2533 mLoadingState = null; 2534 mChildrenStates.clear(); 2535 super.onAdapterChanged(oldAdapter, newAdapter); 2536 } 2537 2538 private void discardLayoutInfo() { 2539 mGrid = null; 2540 mRows = null; 2541 mRowSizeSecondary = null; 2542 mFirstVisiblePos = -1; 2543 mLastVisiblePos = -1; 2544 mRowSecondarySizeRefresh = false; 2545 } 2546 2547 public void setLayoutEnabled(boolean layoutEnabled) { 2548 if (mLayoutEnabled != layoutEnabled) { 2549 mLayoutEnabled = layoutEnabled; 2550 requestLayout(); 2551 } 2552 } 2553 2554 final static class SavedState implements Parcelable { 2555 2556 int index; // index inside adapter of the current view 2557 Bundle childStates = Bundle.EMPTY; 2558 2559 @Override 2560 public void writeToParcel(Parcel out, int flags) { 2561 out.writeInt(index); 2562 out.writeBundle(childStates); 2563 } 2564 2565 @SuppressWarnings("hiding") 2566 public static final Parcelable.Creator<SavedState> CREATOR = 2567 new Parcelable.Creator<SavedState>() { 2568 @Override 2569 public SavedState createFromParcel(Parcel in) { 2570 return new SavedState(in); 2571 } 2572 2573 @Override 2574 public SavedState[] newArray(int size) { 2575 return new SavedState[size]; 2576 } 2577 }; 2578 2579 @Override 2580 public int describeContents() { 2581 return 0; 2582 } 2583 2584 SavedState(Parcel in) { 2585 index = in.readInt(); 2586 childStates = in.readBundle(GridLayoutManager.class.getClassLoader()); 2587 } 2588 2589 SavedState() { 2590 } 2591 } 2592 2593 @Override 2594 public Parcelable onSaveInstanceState() { 2595 SavedState ss = new SavedState(); 2596 for (int i = 0, count = getChildCount(); i < count; i++) { 2597 View view = getChildAt(i); 2598 int position = getPositionByView(view); 2599 if (position != NO_POSITION) { 2600 mChildrenStates.saveOnScreenView(view, position); 2601 } 2602 } 2603 ss.index = getSelection(); 2604 ss.childStates = mChildrenStates.getChildStates(); 2605 return ss; 2606 } 2607 2608 @Override 2609 public void onRestoreInstanceState(Parcelable state) { 2610 if (!(state instanceof SavedState)) { 2611 return; 2612 } 2613 SavedState ss = (SavedState)state; 2614 mLoadingState = ss; 2615 mForceFullLayout = true; 2616 requestLayout(); 2617 } 2618} 2619