GridLayoutManager.java revision 911b1d9ec87dcaa9b4a5a3d4e13c54f21bf03398
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 if (index == mFirstVisiblePos) { 1103 updateScrollMin(); 1104 } 1105 if (index == mLastVisiblePos) { 1106 updateScrollMax(); 1107 } 1108 } 1109 }; 1110 1111 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1112 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1113 : v.getMeasuredWidth(); 1114 if (mFixedRowSizeSecondary > 0) { 1115 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1116 } 1117 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1118 final int horizontalGravity = mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1119 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1120 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1121 // do nothing 1122 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1123 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1124 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1125 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1126 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1127 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1128 } 1129 int left, top, right, bottom; 1130 if (mOrientation == HORIZONTAL) { 1131 left = start; 1132 top = startSecondary; 1133 right = end; 1134 bottom = startSecondary + sizeSecondary; 1135 } else { 1136 top = start; 1137 left = startSecondary; 1138 bottom = end; 1139 right = startSecondary + sizeSecondary; 1140 } 1141 v.layout(left, top, right, bottom); 1142 updateChildOpticalInsets(v, left, top, right, bottom); 1143 updateChildAlignments(v); 1144 } 1145 1146 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1147 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1148 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1149 v.getRight() - right, v.getBottom() - bottom); 1150 } 1151 1152 private void updateChildAlignments(View v) { 1153 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1154 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1155 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1156 } 1157 1158 private void updateChildAlignments() { 1159 for (int i = 0, c = getChildCount(); i < c; i++) { 1160 updateChildAlignments(getChildAt(i)); 1161 } 1162 } 1163 1164 private boolean needsAppendVisibleItem() { 1165 if (mLastVisiblePos < mFocusPosition) { 1166 return true; 1167 } 1168 int right = mScrollOffsetPrimary + mSizePrimary; 1169 for (int i = 0; i < mNumRows; i++) { 1170 if (mRows[i].low == mRows[i].high) { 1171 if (mRows[i].high < right) { 1172 return true; 1173 } 1174 } else if (mRows[i].high < right - mMarginPrimary) { 1175 return true; 1176 } 1177 } 1178 return false; 1179 } 1180 1181 private boolean needsPrependVisibleItem() { 1182 if (mFirstVisiblePos > mFocusPosition) { 1183 return true; 1184 } 1185 for (int i = 0; i < mNumRows; i++) { 1186 if (mRows[i].low == mRows[i].high) { 1187 if (mRows[i].low > mScrollOffsetPrimary) { 1188 return true; 1189 } 1190 } else if (mRows[i].low - mMarginPrimary > mScrollOffsetPrimary) { 1191 return true; 1192 } 1193 } 1194 return false; 1195 } 1196 1197 // Append one column if possible and return true if reach end. 1198 private boolean appendOneVisibleItem() { 1199 while (true) { 1200 if (mLastVisiblePos != NO_POSITION && mLastVisiblePos < mState.getItemCount() -1 && 1201 mLastVisiblePos < mGrid.getLastIndex()) { 1202 // append invisible view of saved location till last row 1203 final int index = mLastVisiblePos + 1; 1204 final int row = mGrid.getLocation(index).row; 1205 mGridProvider.createItem(index, row, true); 1206 if (row == mNumRows - 1) { 1207 return false; 1208 } 1209 } else if ((mLastVisiblePos == NO_POSITION && mState.getItemCount() > 0) || 1210 (mLastVisiblePos != NO_POSITION && 1211 mLastVisiblePos < mState.getItemCount() - 1)) { 1212 mGrid.appendItems(mScrollOffsetPrimary + mSizePrimary); 1213 return false; 1214 } else { 1215 return true; 1216 } 1217 } 1218 } 1219 1220 private void appendVisibleItems() { 1221 while (needsAppendVisibleItem()) { 1222 if (appendOneVisibleItem()) { 1223 break; 1224 } 1225 } 1226 } 1227 1228 // Prepend one column if possible and return true if reach end. 1229 private boolean prependOneVisibleItem() { 1230 while (true) { 1231 if (mFirstVisiblePos > 0) { 1232 if (mFirstVisiblePos > mGrid.getFirstIndex()) { 1233 // prepend invisible view of saved location till first row 1234 final int index = mFirstVisiblePos - 1; 1235 final int row = mGrid.getLocation(index).row; 1236 mGridProvider.createItem(index, row, false); 1237 if (row == 0) { 1238 return false; 1239 } 1240 } else { 1241 mGrid.prependItems(mScrollOffsetPrimary); 1242 return false; 1243 } 1244 } else { 1245 return true; 1246 } 1247 } 1248 } 1249 1250 private void prependVisibleItems() { 1251 while (needsPrependVisibleItem()) { 1252 if (prependOneVisibleItem()) { 1253 break; 1254 } 1255 } 1256 } 1257 1258 private void removeChildAt(int position) { 1259 View v = findViewByPosition(position); 1260 if (v != null) { 1261 if (DEBUG) { 1262 Log.d(getTag(), "removeAndRecycleViewAt " + position); 1263 } 1264 removeAndRecycleView(v, mRecycler); 1265 } 1266 } 1267 1268 private void removeInvisibleViewsAtEnd() { 1269 if (!mPruneChild) { 1270 return; 1271 } 1272 boolean update = false; 1273 while(mLastVisiblePos > mFirstVisiblePos && mLastVisiblePos > mFocusPosition) { 1274 View view = findViewByPosition(mLastVisiblePos); 1275 if (getViewMin(view) > mSizePrimary) { 1276 removeChildAt(mLastVisiblePos); 1277 mLastVisiblePos--; 1278 update = true; 1279 } else { 1280 break; 1281 } 1282 } 1283 if (update) { 1284 updateRowsMinMax(); 1285 } 1286 } 1287 1288 private void removeInvisibleViewsAtFront() { 1289 if (!mPruneChild) { 1290 return; 1291 } 1292 boolean update = false; 1293 while(mLastVisiblePos > mFirstVisiblePos && mFirstVisiblePos < mFocusPosition) { 1294 View view = findViewByPosition(mFirstVisiblePos); 1295 if (getViewMax(view) < 0) { 1296 removeChildAt(mFirstVisiblePos); 1297 mFirstVisiblePos++; 1298 update = true; 1299 } else { 1300 break; 1301 } 1302 } 1303 if (update) { 1304 updateRowsMinMax(); 1305 } 1306 } 1307 1308 private void updateRowsMinMax() { 1309 if (mFirstVisiblePos < 0) { 1310 return; 1311 } 1312 for (int i = 0; i < mNumRows; i++) { 1313 mRows[i].low = Integer.MAX_VALUE; 1314 mRows[i].high = Integer.MIN_VALUE; 1315 } 1316 for (int i = mFirstVisiblePos; i <= mLastVisiblePos; i++) { 1317 View view = findViewByPosition(i); 1318 int row = mGrid.getLocation(i).row; 1319 int low = getViewMin(view) + mScrollOffsetPrimary; 1320 if (low < mRows[row].low) { 1321 mRows[row].low = low; 1322 } 1323 int high = getViewMax(view) + mScrollOffsetPrimary; 1324 if (high > mRows[row].high) { 1325 mRows[row].high = high; 1326 } 1327 } 1328 } 1329 1330 // Fast layout when there is no structure change, adapter change, etc. 1331 protected void fastRelayout() { 1332 initScrollController(); 1333 1334 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 1335 1336 // relayout and repositioning views on each row 1337 for (int i = 0; i < mNumRows; i++) { 1338 List<Integer> row = rows[i]; 1339 final int startSecondary = getRowStartSecondary(i) - mScrollOffsetSecondary; 1340 for (int j = 0, size = row.size(); j < size; j++) { 1341 final int position = row.get(j); 1342 final View view = findViewByPosition(position); 1343 int primaryDelta, start, end; 1344 1345 if (mOrientation == HORIZONTAL) { 1346 final int primarySize = view.getMeasuredWidth(); 1347 if (view.isLayoutRequested()) { 1348 measureChild(view); 1349 } 1350 start = getViewMin(view); 1351 end = start + view.getMeasuredWidth(); 1352 primaryDelta = view.getMeasuredWidth() - primarySize; 1353 if (primaryDelta != 0) { 1354 for (int k = j + 1; k < size; k++) { 1355 findViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1356 } 1357 } 1358 } else { 1359 final int primarySize = view.getMeasuredHeight(); 1360 if (view.isLayoutRequested()) { 1361 measureChild(view); 1362 } 1363 start = getViewMin(view); 1364 end = start + view.getMeasuredHeight(); 1365 primaryDelta = view.getMeasuredHeight() - primarySize; 1366 if (primaryDelta != 0) { 1367 for (int k = j + 1; k < size; k++) { 1368 findViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1369 } 1370 } 1371 } 1372 layoutChild(i, view, start, end, startSecondary); 1373 } 1374 } 1375 1376 updateRowsMinMax(); 1377 appendVisibleItems(); 1378 prependVisibleItems(); 1379 1380 updateRowsMinMax(); 1381 updateScrollMin(); 1382 updateScrollMax(); 1383 updateScrollSecondAxis(); 1384 1385 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1386 View focusView = findViewByPosition(mFocusPosition == NO_POSITION ? 0 : mFocusPosition); 1387 scrollToView(focusView, false); 1388 } 1389 } 1390 1391 @Override 1392 public boolean supportsItemAnimations() { 1393 return mAnimateChildLayout; 1394 } 1395 1396 private void removeAndRecycleAllViews(RecyclerView.Recycler recycler) { 1397 if (DEBUG) Log.v(TAG, "removeAndRecycleAllViews " + getChildCount()); 1398 for (int i = getChildCount() - 1; i >= 0; i--) { 1399 removeAndRecycleViewAt(i, recycler); 1400 } 1401 } 1402 1403 // Lays out items based on the current scroll position 1404 @Override 1405 public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) { 1406 if (DEBUG) { 1407 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1408 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1409 + " inPreLayout " + state.isPreLayout() 1410 + " didStructureChange " + state.didStructureChange() 1411 + " mForceFullLayout " + mForceFullLayout); 1412 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1413 } 1414 1415 if (mNumRows == 0) { 1416 // haven't done measure yet 1417 return; 1418 } 1419 final int itemCount = state.getItemCount(); 1420 if (itemCount < 0) { 1421 return; 1422 } 1423 1424 if (!mLayoutEnabled) { 1425 discardLayoutInfo(); 1426 removeAndRecycleAllViews(recycler); 1427 return; 1428 } 1429 mInLayout = true; 1430 1431 saveContext(recycler, state); 1432 // Track the old focus view so we can adjust our system scroll position 1433 // so that any scroll animations happening now will remain valid. 1434 // We must use same delta in Pre Layout (if prelayout exists) and second layout. 1435 // So we cache the deltas in PreLayout and use it in second layout. 1436 int delta = 0, deltaSecondary = 0; 1437 if (!state.isPreLayout() && mUseDeltaInPreLayout) { 1438 delta = mDeltaInPreLayout; 1439 deltaSecondary = mDeltaSecondaryInPreLayout; 1440 } else { 1441 if (mFocusPosition != NO_POSITION 1442 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1443 View focusView = findViewByPosition(mFocusPosition); 1444 if (focusView != null) { 1445 delta = mWindowAlignment.mainAxis().getSystemScrollPos( 1446 getViewCenter(focusView) + mScrollOffsetPrimary) - mScrollOffsetPrimary; 1447 deltaSecondary = 1448 mWindowAlignment.secondAxis().getSystemScrollPos( 1449 getViewCenterSecondary(focusView) + mScrollOffsetSecondary) 1450 - mScrollOffsetSecondary; 1451 if (mUseDeltaInPreLayout = state.isPreLayout()) { 1452 mDeltaInPreLayout = delta; 1453 mDeltaSecondaryInPreLayout = deltaSecondary; 1454 } 1455 } 1456 } 1457 } 1458 1459 final boolean hasDoneFirstLayout = hasDoneFirstLayout(); 1460 int savedFocusPos = mFocusPosition; 1461 boolean fastRelayout = false; 1462 if (!mState.didStructureChange() && !mForceFullLayout && hasDoneFirstLayout) { 1463 fastRelayout = true; 1464 fastRelayout(); 1465 } else { 1466 boolean hadFocus = mBaseGridView.hasFocus(); 1467 1468 int newFocusPosition = init(mFocusPosition); 1469 if (DEBUG) { 1470 Log.v(getTag(), "mFocusPosition " + mFocusPosition + " newFocusPosition " 1471 + newFocusPosition); 1472 } 1473 1474 // depending on result of init(), either recreating everything 1475 // or try to reuse the row start positions near mFocusPosition 1476 if (mGrid.getSize() == 0) { 1477 // this is a fresh creating all items, starting from 1478 // mFocusPosition with a estimated row index. 1479 mGrid.setStart(newFocusPosition, StaggeredGrid.START_DEFAULT); 1480 1481 // Can't track the old focus view 1482 delta = deltaSecondary = 0; 1483 1484 } else { 1485 // mGrid remembers Locations for the column that 1486 // contains mFocusePosition and also mRows remembers start 1487 // positions of each row. 1488 // Manually re-create child views for that column 1489 int firstIndex = mGrid.getFirstIndex(); 1490 int lastIndex = mGrid.getLastIndex(); 1491 for (int i = firstIndex; i <= lastIndex; i++) { 1492 mGridProvider.createItem(i, mGrid.getLocation(i).row, true); 1493 } 1494 } 1495 // add visible views at end until reach the end of window 1496 appendVisibleItems(); 1497 // add visible views at front until reach the start of window 1498 prependVisibleItems(); 1499 // multiple rounds: scrollToView of first round may drag first/last child into 1500 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1501 int oldFirstVisible; 1502 int oldLastVisible; 1503 do { 1504 oldFirstVisible = mFirstVisiblePos; 1505 oldLastVisible = mLastVisiblePos; 1506 View focusView = findViewByPosition(newFocusPosition); 1507 // we need force to initialize the child view's position 1508 scrollToView(focusView, false); 1509 if (focusView != null && hadFocus) { 1510 focusView.requestFocus(); 1511 } 1512 appendVisibleItems(); 1513 prependVisibleItems(); 1514 removeInvisibleViewsAtFront(); 1515 removeInvisibleViewsAtEnd(); 1516 } while (mFirstVisiblePos != oldFirstVisible || mLastVisiblePos != oldLastVisible); 1517 } 1518 mForceFullLayout = false; 1519 1520 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1521 scrollDirectionPrimary(-delta); 1522 scrollDirectionSecondary(-deltaSecondary); 1523 } 1524 appendVisibleItems(); 1525 prependVisibleItems(); 1526 removeInvisibleViewsAtFront(); 1527 removeInvisibleViewsAtEnd(); 1528 1529 if (DEBUG) { 1530 StringWriter sw = new StringWriter(); 1531 PrintWriter pw = new PrintWriter(sw); 1532 mGrid.debugPrint(pw); 1533 Log.d(getTag(), sw.toString()); 1534 } 1535 1536 if (mRowSecondarySizeRefresh) { 1537 mRowSecondarySizeRefresh = false; 1538 } else { 1539 updateRowSecondarySizeRefresh(); 1540 } 1541 1542 if (!state.isPreLayout()) { 1543 mUseDeltaInPreLayout = false; 1544 if (!fastRelayout || mFocusPosition != savedFocusPos) { 1545 dispatchChildSelected(); 1546 } 1547 } 1548 mInLayout = false; 1549 leaveContext(); 1550 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1551 } 1552 1553 private void offsetChildrenSecondary(int increment) { 1554 final int childCount = getChildCount(); 1555 if (mOrientation == HORIZONTAL) { 1556 for (int i = 0; i < childCount; i++) { 1557 getChildAt(i).offsetTopAndBottom(increment); 1558 } 1559 } else { 1560 for (int i = 0; i < childCount; i++) { 1561 getChildAt(i).offsetLeftAndRight(increment); 1562 } 1563 } 1564 } 1565 1566 private void offsetChildrenPrimary(int increment) { 1567 final int childCount = getChildCount(); 1568 if (mOrientation == VERTICAL) { 1569 for (int i = 0; i < childCount; i++) { 1570 getChildAt(i).offsetTopAndBottom(increment); 1571 } 1572 } else { 1573 for (int i = 0; i < childCount; i++) { 1574 getChildAt(i).offsetLeftAndRight(increment); 1575 } 1576 } 1577 } 1578 1579 @Override 1580 public int scrollHorizontallyBy(int dx, Recycler recycler, RecyclerView.State state) { 1581 if (DEBUG) Log.v(getTag(), "scrollHorizontallyBy " + dx); 1582 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1583 return 0; 1584 } 1585 saveContext(recycler, state); 1586 int result; 1587 if (mOrientation == HORIZONTAL) { 1588 result = scrollDirectionPrimary(dx); 1589 } else { 1590 result = scrollDirectionSecondary(dx); 1591 } 1592 leaveContext(); 1593 return result; 1594 } 1595 1596 @Override 1597 public int scrollVerticallyBy(int dy, Recycler recycler, RecyclerView.State state) { 1598 if (DEBUG) Log.v(getTag(), "scrollVerticallyBy " + dy); 1599 if (!mLayoutEnabled || !hasDoneFirstLayout()) { 1600 return 0; 1601 } 1602 saveContext(recycler, state); 1603 int result; 1604 if (mOrientation == VERTICAL) { 1605 result = scrollDirectionPrimary(dy); 1606 } else { 1607 result = scrollDirectionSecondary(dy); 1608 } 1609 leaveContext(); 1610 return result; 1611 } 1612 1613 // scroll in main direction may add/prune views 1614 private int scrollDirectionPrimary(int da) { 1615 if (da > 0) { 1616 if (!mWindowAlignment.mainAxis().isMaxUnknown()) { 1617 int maxScroll = mWindowAlignment.mainAxis().getMaxScroll(); 1618 if (mScrollOffsetPrimary + da > maxScroll) { 1619 da = maxScroll - mScrollOffsetPrimary; 1620 } 1621 } 1622 } else if (da < 0) { 1623 if (!mWindowAlignment.mainAxis().isMinUnknown()) { 1624 int minScroll = mWindowAlignment.mainAxis().getMinScroll(); 1625 if (mScrollOffsetPrimary + da < minScroll) { 1626 da = minScroll - mScrollOffsetPrimary; 1627 } 1628 } 1629 } 1630 if (da == 0) { 1631 return 0; 1632 } 1633 offsetChildrenPrimary(-da); 1634 mScrollOffsetPrimary += da; 1635 if (mInLayout) { 1636 return da; 1637 } 1638 1639 int childCount = getChildCount(); 1640 boolean updated; 1641 1642 if (da > 0) { 1643 appendVisibleItems(); 1644 } else if (da < 0) { 1645 prependVisibleItems(); 1646 } 1647 updated = getChildCount() > childCount; 1648 childCount = getChildCount(); 1649 1650 if (da > 0) { 1651 removeInvisibleViewsAtFront(); 1652 } else if (da < 0) { 1653 removeInvisibleViewsAtEnd(); 1654 } 1655 updated |= getChildCount() < childCount; 1656 1657 if (updated) { 1658 updateRowSecondarySizeRefresh(); 1659 } 1660 1661 mBaseGridView.invalidate(); 1662 return da; 1663 } 1664 1665 // scroll in second direction will not add/prune views 1666 private int scrollDirectionSecondary(int dy) { 1667 if (dy == 0) { 1668 return 0; 1669 } 1670 offsetChildrenSecondary(-dy); 1671 mScrollOffsetSecondary += dy; 1672 mBaseGridView.invalidate(); 1673 return dy; 1674 } 1675 1676 private void updateScrollMax() { 1677 if (mLastVisiblePos < 0) { 1678 return; 1679 } 1680 final boolean lastAvailable = mLastVisiblePos == mState.getItemCount() - 1; 1681 final boolean maxUnknown = mWindowAlignment.mainAxis().isMaxUnknown(); 1682 if (!lastAvailable && maxUnknown) { 1683 return; 1684 } 1685 int maxEdge = Integer.MIN_VALUE; 1686 int rowIndex = -1; 1687 for (int i = 0; i < mRows.length; i++) { 1688 if (mRows[i].high > maxEdge) { 1689 maxEdge = mRows[i].high; 1690 rowIndex = i; 1691 } 1692 } 1693 int maxScroll = Integer.MAX_VALUE; 1694 for (int i = mLastVisiblePos; i >= mFirstVisiblePos; i--) { 1695 StaggeredGrid.Location location = mGrid.getLocation(i); 1696 if (location != null && location.row == rowIndex) { 1697 int savedMaxEdge = mWindowAlignment.mainAxis().getMaxEdge(); 1698 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1699 maxScroll = mWindowAlignment 1700 .mainAxis().getSystemScrollPos(mScrollOffsetPrimary 1701 + getViewCenter(findViewByPosition(i))); 1702 mWindowAlignment.mainAxis().setMaxEdge(savedMaxEdge); 1703 break; 1704 } 1705 } 1706 if (lastAvailable) { 1707 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1708 mWindowAlignment.mainAxis().setMaxScroll(maxScroll); 1709 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge + 1710 " scrollMax to " + maxScroll); 1711 } else { 1712 // the maxScroll for currently last visible item is larger, 1713 // so we must invalidate the max scroll value. 1714 if (maxScroll > mWindowAlignment.mainAxis().getMaxScroll()) { 1715 mWindowAlignment.mainAxis().invalidateScrollMax(); 1716 if (DEBUG) Log.v(getTag(), "Invalidate scrollMax since it should be " 1717 + "greater than " + maxScroll); 1718 } 1719 } 1720 } 1721 1722 private void updateScrollMin() { 1723 if (mFirstVisiblePos < 0) { 1724 return; 1725 } 1726 final boolean firstAvailable = mFirstVisiblePos == 0; 1727 final boolean minUnknown = mWindowAlignment.mainAxis().isMinUnknown(); 1728 if (!firstAvailable && minUnknown) { 1729 return; 1730 } 1731 int minEdge = Integer.MAX_VALUE; 1732 int rowIndex = -1; 1733 for (int i = 0; i < mRows.length; i++) { 1734 if (mRows[i].low < minEdge) { 1735 minEdge = mRows[i].low; 1736 rowIndex = i; 1737 } 1738 } 1739 int minScroll = Integer.MIN_VALUE; 1740 for (int i = mFirstVisiblePos; i <= mLastVisiblePos; i++) { 1741 StaggeredGrid.Location location = mGrid.getLocation(i); 1742 if (location != null && location.row == rowIndex) { 1743 int savedMinEdge = mWindowAlignment.mainAxis().getMinEdge(); 1744 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1745 minScroll = mWindowAlignment 1746 .mainAxis().getSystemScrollPos(mScrollOffsetPrimary 1747 + getViewCenter(findViewByPosition(i))); 1748 mWindowAlignment.mainAxis().setMinEdge(savedMinEdge); 1749 break; 1750 } 1751 } 1752 if (firstAvailable) { 1753 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1754 mWindowAlignment.mainAxis().setMinScroll(minScroll); 1755 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge + 1756 " scrollMin to " + minScroll); 1757 } else { 1758 // the minScroll for currently first visible item is smaller, 1759 // so we must invalidate the min scroll value. 1760 if (minScroll < mWindowAlignment.mainAxis().getMinScroll()) { 1761 mWindowAlignment.mainAxis().invalidateScrollMin(); 1762 if (DEBUG) Log.v(getTag(), "Invalidate scrollMin, since it should be " 1763 + "less than " + minScroll); 1764 } 1765 } 1766 } 1767 1768 private void updateScrollSecondAxis() { 1769 mWindowAlignment.secondAxis().setMinEdge(0); 1770 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1771 } 1772 1773 private void initScrollController() { 1774 mWindowAlignment.horizontal.setSize(getWidth()); 1775 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1776 mWindowAlignment.vertical.setSize(getHeight()); 1777 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1778 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1779 1780 if (DEBUG) { 1781 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1782 + " mWindowAlignment " + mWindowAlignment); 1783 } 1784 } 1785 1786 public void setSelection(RecyclerView parent, int position) { 1787 setSelection(parent, position, false); 1788 } 1789 1790 public void setSelectionSmooth(RecyclerView parent, int position) { 1791 setSelection(parent, position, true); 1792 } 1793 1794 public int getSelection() { 1795 return mFocusPosition; 1796 } 1797 1798 public void setSelection(RecyclerView parent, int position, boolean smooth) { 1799 if (mFocusPosition == position) { 1800 return; 1801 } 1802 View view = findViewByPosition(position); 1803 if (view != null) { 1804 scrollToView(view, smooth); 1805 } else { 1806 mFocusPosition = position; 1807 if (!mLayoutEnabled) { 1808 return; 1809 } 1810 if (smooth) { 1811 if (!hasDoneFirstLayout()) { 1812 Log.w(getTag(), "setSelectionSmooth should " + 1813 "not be called before first layout pass"); 1814 return; 1815 } 1816 LinearSmoothScroller linearSmoothScroller = 1817 new LinearSmoothScroller(parent.getContext()) { 1818 @Override 1819 public PointF computeScrollVectorForPosition(int targetPosition) { 1820 if (getChildCount() == 0) { 1821 return null; 1822 } 1823 final int firstChildPos = getPosition(getChildAt(0)); 1824 final int direction = targetPosition < firstChildPos ? -1 : 1; 1825 if (mOrientation == HORIZONTAL) { 1826 return new PointF(direction, 0); 1827 } else { 1828 return new PointF(0, direction); 1829 } 1830 } 1831 @Override 1832 protected void onTargetFound(View targetView, 1833 RecyclerView.State state, Action action) { 1834 if (hasFocus()) { 1835 targetView.requestFocus(); 1836 } else { 1837 dispatchChildSelected(); 1838 } 1839 if (getScrollPosition(targetView, mTempDeltas)) { 1840 int dx, dy; 1841 if (mOrientation == HORIZONTAL) { 1842 dx = mTempDeltas[0]; 1843 dy = mTempDeltas[1]; 1844 } else { 1845 dx = mTempDeltas[1]; 1846 dy = mTempDeltas[0]; 1847 } 1848 final int distance = (int) Math.sqrt(dx * dx + dy * dy); 1849 final int time = calculateTimeForDeceleration(distance); 1850 action.update(dx, dy, time, mDecelerateInterpolator); 1851 } 1852 } 1853 }; 1854 linearSmoothScroller.setTargetPosition(position); 1855 startSmoothScroll(linearSmoothScroller); 1856 } else { 1857 mForceFullLayout = true; 1858 parent.requestLayout(); 1859 } 1860 } 1861 } 1862 1863 @Override 1864 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 1865 boolean needsLayout = false; 1866 if (itemCount != 0) { 1867 if (mFirstVisiblePos < 0) { 1868 needsLayout = true; 1869 } else if (!(positionStart > mLastVisiblePos + 1 || 1870 positionStart + itemCount < mFirstVisiblePos - 1)) { 1871 needsLayout = true; 1872 } 1873 } 1874 if (needsLayout) { 1875 recyclerView.requestLayout(); 1876 } 1877 } 1878 1879 @Override 1880 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 1881 if (mFocusSearchDisabled) { 1882 return true; 1883 } 1884 if (!mInLayout) { 1885 scrollToView(child, true); 1886 } 1887 return true; 1888 } 1889 1890 @Override 1891 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 1892 boolean immediate) { 1893 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 1894 return false; 1895 } 1896 1897 int getScrollOffsetX() { 1898 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 1899 } 1900 1901 int getScrollOffsetY() { 1902 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 1903 } 1904 1905 public void getViewSelectedOffsets(View view, int[] offsets) { 1906 int scrollOffsetX = getScrollOffsetX(); 1907 int scrollOffsetY = getScrollOffsetY(); 1908 int viewCenterX = scrollOffsetX + getViewCenterX(view); 1909 int viewCenterY = scrollOffsetY + getViewCenterY(view); 1910 offsets[0] = mWindowAlignment.horizontal.getSystemScrollPos(viewCenterX) - scrollOffsetX; 1911 offsets[1] = mWindowAlignment.vertical.getSystemScrollPos(viewCenterY) - scrollOffsetY; 1912 } 1913 1914 /** 1915 * Scroll to a given child view and change mFocusPosition. 1916 */ 1917 private void scrollToView(View view, boolean smooth) { 1918 int newFocusPosition = getPositionByView(view); 1919 if (newFocusPosition != mFocusPosition) { 1920 mFocusPosition = newFocusPosition; 1921 if (!mInLayout) { 1922 dispatchChildSelected(); 1923 } 1924 } 1925 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 1926 mBaseGridView.invalidate(); 1927 } 1928 if (view == null) { 1929 return; 1930 } 1931 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 1932 // transfer focus to the child if it does not have focus yet (e.g. triggered 1933 // by setSelection()) 1934 view.requestFocus(); 1935 } 1936 if (getScrollPosition(view, mTempDeltas)) { 1937 scrollGrid(mTempDeltas[0], mTempDeltas[1], smooth); 1938 } 1939 } 1940 1941 private boolean getScrollPosition(View view, int[] deltas) { 1942 switch (mFocusScrollStrategy) { 1943 case BaseGridView.FOCUS_SCROLL_ALIGNED: 1944 default: 1945 return getAlignedPosition(view, deltas); 1946 case BaseGridView.FOCUS_SCROLL_ITEM: 1947 case BaseGridView.FOCUS_SCROLL_PAGE: 1948 return getNoneAlignedPosition(view, deltas); 1949 } 1950 } 1951 1952 private boolean getNoneAlignedPosition(View view, int[] deltas) { 1953 int pos = getPositionByView(view); 1954 int viewMin = getViewMin(view); 1955 int viewMax = getViewMax(view); 1956 // we either align "firstView" to left/top padding edge 1957 // or align "lastView" to right/bottom padding edge 1958 View firstView = null; 1959 View lastView = null; 1960 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 1961 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 1962 final int row = mGrid.getLocation(pos).row; 1963 if (viewMin < paddingLow) { 1964 // view enters low padding area: 1965 firstView = view; 1966 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1967 // scroll one "page" left/top, 1968 // align first visible item of the "page" at the low padding edge. 1969 while (!prependOneVisibleItem()) { 1970 List<Integer> positions = 1971 mGrid.getItemPositionsInRows(mFirstVisiblePos, pos)[row]; 1972 firstView = findViewByPosition(positions.get(0)); 1973 if (viewMax - getViewMin(firstView) > clientSize) { 1974 if (positions.size() > 1) { 1975 firstView = findViewByPosition(positions.get(1)); 1976 } 1977 break; 1978 } 1979 } 1980 } 1981 } else if (viewMax > clientSize + paddingLow) { 1982 // view enters high padding area: 1983 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1984 // scroll whole one page right/bottom, align view at the low padding edge. 1985 firstView = view; 1986 do { 1987 List<Integer> positions = 1988 mGrid.getItemPositionsInRows(pos, mLastVisiblePos)[row]; 1989 lastView = findViewByPosition(positions.get(positions.size() - 1)); 1990 if (getViewMax(lastView) - viewMin > clientSize) { 1991 lastView = null; 1992 break; 1993 } 1994 } while (!appendOneVisibleItem()); 1995 if (lastView != null) { 1996 // however if we reached end, we should align last view. 1997 firstView = null; 1998 } 1999 } else { 2000 lastView = view; 2001 } 2002 } 2003 int scrollPrimary = 0; 2004 int scrollSecondary = 0; 2005 if (firstView != null) { 2006 scrollPrimary = getViewMin(firstView) - paddingLow; 2007 } else if (lastView != null) { 2008 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 2009 } 2010 View secondaryAlignedView; 2011 if (firstView != null) { 2012 secondaryAlignedView = firstView; 2013 } else if (lastView != null) { 2014 secondaryAlignedView = lastView; 2015 } else { 2016 secondaryAlignedView = view; 2017 } 2018 int viewCenterSecondary = mScrollOffsetSecondary + 2019 getViewCenterSecondary(secondaryAlignedView); 2020 scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(viewCenterSecondary); 2021 scrollSecondary -= mScrollOffsetSecondary; 2022 if (scrollPrimary != 0 || scrollSecondary != 0) { 2023 deltas[0] = scrollPrimary; 2024 deltas[1] = scrollSecondary; 2025 return true; 2026 } 2027 return false; 2028 } 2029 2030 private boolean getAlignedPosition(View view, int[] deltas) { 2031 int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 2032 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 2033 2034 int scrollPrimary = mWindowAlignment.mainAxis().getSystemScrollPos(viewCenterPrimary); 2035 int scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(viewCenterSecondary); 2036 if (DEBUG) { 2037 Log.v(getTag(), "getAlignedPosition " + scrollPrimary + " " + scrollSecondary 2038 +" " + mWindowAlignment); 2039 } 2040 scrollPrimary -= mScrollOffsetPrimary; 2041 scrollSecondary -= mScrollOffsetSecondary; 2042 if (scrollPrimary != 0 || scrollSecondary != 0) { 2043 deltas[0] = scrollPrimary; 2044 deltas[1] = scrollSecondary; 2045 return true; 2046 } 2047 return false; 2048 } 2049 2050 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 2051 if (mInLayout) { 2052 scrollDirectionPrimary(scrollPrimary); 2053 scrollDirectionSecondary(scrollSecondary); 2054 } else { 2055 int scrollX; 2056 int scrollY; 2057 if (mOrientation == HORIZONTAL) { 2058 scrollX = scrollPrimary; 2059 scrollY = scrollSecondary; 2060 } else { 2061 scrollX = scrollSecondary; 2062 scrollY = scrollPrimary; 2063 } 2064 if (smooth) { 2065 mBaseGridView.smoothScrollBy(scrollX, scrollY); 2066 } else { 2067 mBaseGridView.scrollBy(scrollX, scrollY); 2068 } 2069 } 2070 } 2071 2072 public void setAnimateChildLayout(boolean animateChildLayout) { 2073 mAnimateChildLayout = animateChildLayout; 2074 } 2075 2076 public boolean isChildLayoutAnimated() { 2077 return mAnimateChildLayout; 2078 } 2079 2080 public void setPruneChild(boolean pruneChild) { 2081 if (mPruneChild != pruneChild) { 2082 mPruneChild = pruneChild; 2083 if (mPruneChild) { 2084 requestLayout(); 2085 } 2086 } 2087 } 2088 2089 public boolean getPruneChild() { 2090 return mPruneChild; 2091 } 2092 2093 private int findImmediateChildIndex(View view) { 2094 while (view != null && view != mBaseGridView) { 2095 int index = mBaseGridView.indexOfChild(view); 2096 if (index >= 0) { 2097 return index; 2098 } 2099 view = (View) view.getParent(); 2100 } 2101 return NO_POSITION; 2102 } 2103 2104 void setFocusSearchDisabled(boolean disabled) { 2105 mFocusSearchDisabled = disabled; 2106 } 2107 2108 boolean isFocusSearchDisabled() { 2109 return mFocusSearchDisabled; 2110 } 2111 2112 @Override 2113 public View onInterceptFocusSearch(View focused, int direction) { 2114 if (mFocusSearchDisabled) { 2115 return focused; 2116 } 2117 return null; 2118 } 2119 2120 boolean hasPreviousViewInSameRow(int pos) { 2121 if (mGrid == null || pos == NO_POSITION) { 2122 return false; 2123 } 2124 if (mFirstVisiblePos > 0) { 2125 return true; 2126 } 2127 final int focusedRow = mGrid.getLocation(pos).row; 2128 for (int i = getChildCount() - 1; i >= 0; i--) { 2129 int position = getPositionByIndex(i); 2130 StaggeredGrid.Location loc = mGrid.getLocation(position); 2131 if (loc != null && loc.row == focusedRow) { 2132 if (position < pos) { 2133 return true; 2134 } 2135 } 2136 } 2137 return false; 2138 } 2139 2140 @Override 2141 public boolean onAddFocusables(RecyclerView recyclerView, 2142 ArrayList<View> views, int direction, int focusableMode) { 2143 if (mFocusSearchDisabled) { 2144 return true; 2145 } 2146 // If this viewgroup or one of its children currently has focus then we 2147 // consider our children for focus searching in main direction on the same row. 2148 // If this viewgroup has no focus and using focus align, we want the system 2149 // to ignore our children and pass focus to the viewgroup, which will pass 2150 // focus on to its children appropriately. 2151 // If this viewgroup has no focus and not using focus align, we want to 2152 // consider the child that does not overlap with padding area. 2153 if (recyclerView.hasFocus()) { 2154 final int movement = getMovement(direction); 2155 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2156 // Move on secondary direction uses default addFocusables(). 2157 return false; 2158 } 2159 final View focused = recyclerView.findFocus(); 2160 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2161 // Add focusables of focused item. 2162 if (focusedPos != NO_POSITION) { 2163 findViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2164 } 2165 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2166 mGrid.getLocation(focusedPos).row : NO_POSITION; 2167 // Add focusables of next neighbor of same row on the focus search direction. 2168 if (mGrid != null) { 2169 final int focusableCount = views.size(); 2170 for (int i = 0, count = getChildCount(); i < count; i++) { 2171 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2172 final View child = getChildAt(index); 2173 if (child.getVisibility() != View.VISIBLE) { 2174 continue; 2175 } 2176 int position = getPositionByIndex(index); 2177 StaggeredGrid.Location loc = mGrid.getLocation(position); 2178 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2179 if (focusedPos == NO_POSITION || 2180 (movement == NEXT_ITEM && position > focusedPos) 2181 || (movement == PREV_ITEM && position < focusedPos)) { 2182 child.addFocusables(views, direction, focusableMode); 2183 if (views.size() > focusableCount) { 2184 break; 2185 } 2186 } 2187 } 2188 } 2189 } 2190 } else { 2191 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2192 // adding views not overlapping padding area to avoid scrolling in gaining focus 2193 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2194 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2195 int focusableCount = views.size(); 2196 for (int i = 0, count = getChildCount(); i < count; i++) { 2197 View child = getChildAt(i); 2198 if (child.getVisibility() == View.VISIBLE) { 2199 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2200 child.addFocusables(views, direction, focusableMode); 2201 } 2202 } 2203 } 2204 // if we cannot find any, then just add all children. 2205 if (views.size() == focusableCount) { 2206 for (int i = 0, count = getChildCount(); i < count; i++) { 2207 View child = getChildAt(i); 2208 if (child.getVisibility() == View.VISIBLE) { 2209 child.addFocusables(views, direction, focusableMode); 2210 } 2211 } 2212 if (views.size() != focusableCount) { 2213 return true; 2214 } 2215 } else { 2216 return true; 2217 } 2218 // if still cannot find any, fall through and add itself 2219 } 2220 if (recyclerView.isFocusable()) { 2221 views.add(recyclerView); 2222 } 2223 } 2224 return true; 2225 } 2226 2227 @Override 2228 public View onFocusSearchFailed(View focused, int direction, Recycler recycler, 2229 RecyclerView.State state) { 2230 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2231 2232 saveContext(recycler, state); 2233 View view = null; 2234 int movement = getMovement(direction); 2235 final FocusFinder ff = FocusFinder.getInstance(); 2236 if (movement == NEXT_ITEM) { 2237 while (view == null && !appendOneVisibleItem()) { 2238 view = ff.findNextFocus(mBaseGridView, focused, direction); 2239 } 2240 } else if (movement == PREV_ITEM){ 2241 while (view == null && !prependOneVisibleItem()) { 2242 view = ff.findNextFocus(mBaseGridView, focused, direction); 2243 } 2244 } 2245 if (view == null) { 2246 // returning the same view to prevent focus lost when scrolling past the end of the list 2247 if (movement == PREV_ITEM) { 2248 view = mFocusOutFront ? null : focused; 2249 } else if (movement == NEXT_ITEM){ 2250 view = mFocusOutEnd ? null : focused; 2251 } 2252 } 2253 leaveContext(); 2254 if (DEBUG) Log.v(getTag(), "returning view " + view); 2255 return view; 2256 } 2257 2258 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2259 Rect previouslyFocusedRect) { 2260 switch (mFocusScrollStrategy) { 2261 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2262 default: 2263 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2264 direction, previouslyFocusedRect); 2265 case BaseGridView.FOCUS_SCROLL_PAGE: 2266 case BaseGridView.FOCUS_SCROLL_ITEM: 2267 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2268 direction, previouslyFocusedRect); 2269 } 2270 } 2271 2272 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2273 int direction, Rect previouslyFocusedRect) { 2274 View view = findViewByPosition(mFocusPosition); 2275 if (view != null) { 2276 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2277 if (!result && DEBUG) { 2278 Log.w(getTag(), "failed to request focus on " + view); 2279 } 2280 return result; 2281 } 2282 return false; 2283 } 2284 2285 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2286 int direction, Rect previouslyFocusedRect) { 2287 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2288 int index; 2289 int increment; 2290 int end; 2291 int count = getChildCount(); 2292 if ((direction & View.FOCUS_FORWARD) != 0) { 2293 index = 0; 2294 increment = 1; 2295 end = count; 2296 } else { 2297 index = count - 1; 2298 increment = -1; 2299 end = -1; 2300 } 2301 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2302 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2303 for (int i = index; i != end; i += increment) { 2304 View child = getChildAt(i); 2305 if (child.getVisibility() == View.VISIBLE) { 2306 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2307 if (child.requestFocus(direction, previouslyFocusedRect)) { 2308 return true; 2309 } 2310 } 2311 } 2312 } 2313 return false; 2314 } 2315 2316 private final static int PREV_ITEM = 0; 2317 private final static int NEXT_ITEM = 1; 2318 private final static int PREV_ROW = 2; 2319 private final static int NEXT_ROW = 3; 2320 2321 private int getMovement(int direction) { 2322 int movement = View.FOCUS_LEFT; 2323 2324 if (mOrientation == HORIZONTAL) { 2325 switch(direction) { 2326 case View.FOCUS_LEFT: 2327 movement = PREV_ITEM; 2328 break; 2329 case View.FOCUS_RIGHT: 2330 movement = NEXT_ITEM; 2331 break; 2332 case View.FOCUS_UP: 2333 movement = PREV_ROW; 2334 break; 2335 case View.FOCUS_DOWN: 2336 movement = NEXT_ROW; 2337 break; 2338 } 2339 } else if (mOrientation == VERTICAL) { 2340 switch(direction) { 2341 case View.FOCUS_LEFT: 2342 movement = PREV_ROW; 2343 break; 2344 case View.FOCUS_RIGHT: 2345 movement = NEXT_ROW; 2346 break; 2347 case View.FOCUS_UP: 2348 movement = PREV_ITEM; 2349 break; 2350 case View.FOCUS_DOWN: 2351 movement = NEXT_ITEM; 2352 break; 2353 } 2354 } 2355 2356 return movement; 2357 } 2358 2359 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2360 View view = findViewByPosition(mFocusPosition); 2361 if (view == null) { 2362 return i; 2363 } 2364 int focusIndex = recyclerView.indexOfChild(view); 2365 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2366 // drawing order is 0 1 2 3 9 8 7 6 5 4 2367 if (i < focusIndex) { 2368 return i; 2369 } else if (i < childCount - 1) { 2370 return focusIndex + childCount - 1 - i; 2371 } else { 2372 return focusIndex; 2373 } 2374 } 2375 2376 @Override 2377 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2378 RecyclerView.Adapter newAdapter) { 2379 discardLayoutInfo(); 2380 mFocusPosition = NO_POSITION; 2381 super.onAdapterChanged(oldAdapter, newAdapter); 2382 } 2383 2384 private void discardLayoutInfo() { 2385 mGrid = null; 2386 mRows = null; 2387 mRowSizeSecondary = null; 2388 mFirstVisiblePos = -1; 2389 mLastVisiblePos = -1; 2390 mRowSecondarySizeRefresh = false; 2391 } 2392 2393 public void setLayoutEnabled(boolean layoutEnabled) { 2394 if (mLayoutEnabled != layoutEnabled) { 2395 mLayoutEnabled = layoutEnabled; 2396 requestLayout(); 2397 } 2398 } 2399} 2400