GridLayoutManager.java revision 4510b275c55d9a3dae13af38196d3bc6affd3dfc
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.Rect; 19import android.support.v7.widget.RecyclerView; 20import android.support.v7.widget.RecyclerView.Adapter; 21import android.support.v7.widget.RecyclerView.Recycler; 22import android.support.v7.widget.RecyclerView.State; 23 24import static android.support.v7.widget.RecyclerView.NO_ID; 25import static android.support.v7.widget.RecyclerView.NO_POSITION; 26import static android.support.v7.widget.RecyclerView.HORIZONTAL; 27import static android.support.v7.widget.RecyclerView.VERTICAL; 28 29import android.util.AttributeSet; 30import android.util.Log; 31import android.view.FocusFinder; 32import android.view.Gravity; 33import android.view.View; 34import android.view.ViewParent; 35import android.view.View.MeasureSpec; 36import android.view.ViewGroup.MarginLayoutParams; 37import android.view.ViewGroup; 38import android.view.animation.DecelerateInterpolator; 39import android.view.animation.Interpolator; 40 41import java.io.PrintWriter; 42import java.io.StringWriter; 43import java.util.ArrayList; 44import java.util.List; 45 46final class GridLayoutManager extends RecyclerView.LayoutManager { 47 48 /* 49 * LayoutParams for {@link HorizontalGridView} and {@link VerticalGridView}. 50 * The class currently does three internal jobs: 51 * - Saves optical bounds insets. 52 * - Caches focus align view center. 53 * - Manages child view layout animation. 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 // For animations 71 private TimeAnimator mAnimator; 72 private long mDuration; 73 private boolean mFirstAttachedInLayout; 74 // current virtual view position (scrollOffset + left/top) in the GridLayoutManager 75 private int mViewX, mViewY; 76 private int mSize; 77 // animation start value of translation x and y 78 private float mAnimationStartTranslationX, mAnimationStartTranslationY; 79 80 // The direction this view should be laid out along the primary dimension. 81 private boolean mLayoutForward; 82 83 // Orientation of the grid layout 84 private int mOrientation; 85 86 public LayoutParams(Context c, AttributeSet attrs) { 87 super(c, attrs); 88 } 89 90 public LayoutParams(int width, int height) { 91 super(width, height); 92 } 93 94 public LayoutParams(MarginLayoutParams source) { 95 super(source); 96 } 97 98 public LayoutParams(ViewGroup.LayoutParams source) { 99 super(source); 100 } 101 102 public LayoutParams(RecyclerView.LayoutParams source) { 103 super(source); 104 } 105 106 public LayoutParams(LayoutParams source) { 107 super(source); 108 } 109 110 void onViewAttached(boolean inLayout) { 111 mFirstAttachedInLayout = inLayout; 112 } 113 114 void onViewDetached() { 115 endAnimate(); 116 } 117 118 int getAlignX() { 119 return mAlignX; 120 } 121 122 int getAlignY() { 123 return mAlignY; 124 } 125 126 int getOpticalLeft(View view) { 127 return view.getLeft() + mLeftInset; 128 } 129 130 int getOpticalTop(View view) { 131 return view.getTop() + mTopInset; 132 } 133 134 int getOpticalRight(View view) { 135 return view.getRight() - mRighInset; 136 } 137 138 int getOpticalBottom(View view) { 139 return view.getBottom() - mBottomInset; 140 } 141 142 int getOpticalWidth(View view) { 143 return view.getWidth() - mLeftInset - mRighInset; 144 } 145 146 int getOpticalHeight(View view) { 147 return view.getHeight() - mTopInset - mBottomInset; 148 } 149 150 void setAlignX(int alignX) { 151 mAlignX = alignX; 152 } 153 154 void setAlignY(int alignY) { 155 mAlignY = alignY; 156 } 157 158 void setOpticalInsets(int leftInset, int topInset, int rightInset, int bottomInset) { 159 mLeftInset = leftInset; 160 mTopInset = topInset; 161 mRighInset = rightInset; 162 mBottomInset = bottomInset; 163 } 164 165 private TimeAnimator.TimeListener mTimeListener = new TimeAnimator.TimeListener() { 166 @Override 167 public void onTimeUpdate(TimeAnimator animation, long totalTime, long deltaTime) { 168 if (mView == null) { 169 return; 170 } 171 if (totalTime >= mDuration) { 172 endAnimate(); 173 } else { 174 float fraction = (float) (totalTime / (double)mDuration); 175 float fractionToEnd = 1 - mAnimator 176 .getInterpolator().getInterpolation(fraction); 177 if (mOrientation == HORIZONTAL) { 178 if (mLayoutForward) { 179 mView.setTranslationX(fractionToEnd * mAnimationStartTranslationX); 180 } else { 181 mView.setTranslationX(fractionToEnd * mAnimationStartTranslationX - 182 fractionToEnd * (mView.getMeasuredWidth() - mSize)); 183 } 184 } else { 185 if (mLayoutForward) { 186 mView.setTranslationY(fractionToEnd * mAnimationStartTranslationY); 187 } else { 188 mView.setTranslationY(fractionToEnd * mAnimationStartTranslationY - 189 fractionToEnd * (mView.getMeasuredHeight() - mSize)); 190 } 191 } 192 invalidateItemDecoration(); 193 } 194 } 195 }; 196 197 void recordStart(int orientation, View view) { 198 mViewX = getOpticalLeft(view); 199 mViewY = getOpticalTop(view); 200 mOrientation = orientation; 201 mSize = mOrientation == HORIZONTAL ? view.getMeasuredWidth() : view.getMeasuredHeight(); 202 } 203 204 void startAnimate(View view, 205 long duration, long startDelay, Interpolator interpolator) { 206 if (mFirstAttachedInLayout) { 207 // if the view is just attached in layout pass, do not run animation 208 mFirstAttachedInLayout = false; 209 return; 210 } 211 int newViewX = getOpticalLeft(view); 212 int newViewY = getOpticalTop(view); 213 if (newViewX != mViewX || newViewY != mViewY) { 214 if (mAnimator == null) { 215 mAnimator = new TimeAnimator(); 216 mAnimator.setTimeListener(mTimeListener); 217 } 218 mView = view; 219 mAnimationStartTranslationX = mView.getTranslationX(); 220 mAnimationStartTranslationY = mView.getTranslationY(); 221 mAnimator.cancel(); 222 mAnimationStartTranslationX += mViewX - newViewX; 223 mAnimationStartTranslationY += mViewY - newViewY; 224 mDuration = duration; 225 mAnimator.setDuration(mDuration); 226 mAnimator.setInterpolator(interpolator); 227 mAnimator.setStartDelay(startDelay); 228 mAnimator.start(); 229 // put it at initial location 230 mTimeListener.onTimeUpdate(mAnimator, 0, 0); 231 } 232 } 233 234 void endAnimate() { 235 if (mAnimator != null) { 236 mAnimator.end(); 237 } 238 if (mView != null) { 239 mSize = mOrientation == HORIZONTAL ? 240 mView.getMeasuredWidth() : mView.getMeasuredHeight(); 241 mView.setTranslationX(0); 242 mView.setTranslationY(0); 243 mView = null; 244 } 245 } 246 247 private void invalidateItemDecoration() { 248 ViewParent parent = mView.getParent(); 249 if (parent instanceof RecyclerView) { 250 // TODO: we only need invalidate parent if it has ItemDecoration 251 ((RecyclerView) parent).invalidate(); 252 } 253 } 254 } 255 256 private static final String TAG = "GridLayoutManager"; 257 private static final boolean DEBUG = false; 258 259 private static final Interpolator sDefaultAnimationChildLayoutInterpolator 260 = new DecelerateInterpolator(); 261 262 private static final long DEFAULT_CHILD_ANIMATION_DURATION_MS = 250; 263 264 private String getTag() { 265 return TAG + ":" + mBaseGridView.getId(); 266 } 267 268 private final BaseGridView mBaseGridView; 269 270 /** 271 * The orientation of a "row". 272 */ 273 private int mOrientation = HORIZONTAL; 274 275 private RecyclerView.Adapter mAdapter; 276 private RecyclerView.Recycler mRecycler; 277 278 private boolean mInLayout = false; 279 280 private OnChildSelectedListener mChildSelectedListener = null; 281 282 /** 283 * The focused position, it's not the currently visually aligned position 284 * but it is the final position that we intend to focus on. If there are 285 * multiple setSelection() called, mFocusPosition saves last value. 286 */ 287 private int mFocusPosition = NO_POSITION; 288 289 /** 290 * Force a full layout under certain situations. 291 */ 292 private boolean mForceFullLayout; 293 294 /** 295 * True if layout is enabled. 296 */ 297 private boolean mLayoutEnabled = true; 298 299 /** 300 * The scroll offsets of the viewport relative to the entire view. 301 */ 302 private int mScrollOffsetPrimary; 303 private int mScrollOffsetSecondary; 304 305 /** 306 * User-specified row height/column width. Can be WRAP_CONTENT. 307 */ 308 private int mRowSizeSecondaryRequested; 309 310 /** 311 * The fixed size of each grid item in the secondary direction. This corresponds to 312 * the row height, equal for all rows. Grid items may have variable length 313 * in the primary direction. 314 */ 315 private int mFixedRowSizeSecondary; 316 317 /** 318 * Tracks the secondary size of each row. 319 */ 320 private int[] mRowSizeSecondary; 321 322 /** 323 * Flag controlling whether the current/next layout should 324 * be updating the secondary size of rows. 325 */ 326 private boolean mRowSecondarySizeRefresh; 327 328 /** 329 * The maximum measured size of the view. 330 */ 331 private int mMaxSizeSecondary; 332 333 /** 334 * Margin between items. 335 */ 336 private int mHorizontalMargin; 337 /** 338 * Margin between items vertically. 339 */ 340 private int mVerticalMargin; 341 /** 342 * Margin in main direction. 343 */ 344 private int mMarginPrimary; 345 /** 346 * Margin in second direction. 347 */ 348 private int mMarginSecondary; 349 /** 350 * How to position child in secondary direction. 351 */ 352 private int mGravity = Gravity.LEFT | Gravity.TOP; 353 /** 354 * The number of rows in the grid. 355 */ 356 private int mNumRows; 357 /** 358 * Number of rows requested, can be 0 to be determined by parent size and 359 * rowHeight. 360 */ 361 private int mNumRowsRequested = 1; 362 363 /** 364 * Tracking start/end position of each row for visible items. 365 */ 366 private StaggeredGrid.Row[] mRows; 367 368 /** 369 * Saves grid information of each view. 370 */ 371 private StaggeredGrid mGrid; 372 /** 373 * Position of first item (included) that has attached views. 374 */ 375 private int mFirstVisiblePos; 376 /** 377 * Position of last item (included) that has attached views. 378 */ 379 private int mLastVisiblePos; 380 381 /** 382 * Focus Scroll strategy. 383 */ 384 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 385 /** 386 * Defines how item view is aligned in the window. 387 */ 388 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 389 390 /** 391 * Defines how item view is aligned. 392 */ 393 private final ItemAlignment mItemAlignment = new ItemAlignment(); 394 395 /** 396 * Dimensions of the view, width or height depending on orientation. 397 */ 398 private int mSizePrimary; 399 400 /** 401 * Allow DPAD key to navigate out at the front of the View (where position = 0), 402 * default is false. 403 */ 404 private boolean mFocusOutFront; 405 406 /** 407 * Allow DPAD key to navigate out at the end of the view, default is false. 408 */ 409 private boolean mFocusOutEnd; 410 411 /** 412 * True if focus search is disabled. 413 */ 414 private boolean mFocusSearchDisabled; 415 416 /** 417 * Animate layout changes from a child resizing or adding/removing a child. 418 */ 419 private boolean mAnimateChildLayout = true; 420 421 /** 422 * True if prune child, might be disabled during transition. 423 */ 424 private boolean mPruneChild = true; 425 426 /** 427 * Interpolator used to animate layout of children. 428 */ 429 private Interpolator mAnimateLayoutChildInterpolator = sDefaultAnimationChildLayoutInterpolator; 430 431 /** 432 * Duration used to animate layout of children. 433 */ 434 private long mAnimateLayoutChildDuration = DEFAULT_CHILD_ANIMATION_DURATION_MS; 435 436 public GridLayoutManager(BaseGridView baseGridView) { 437 mBaseGridView = baseGridView; 438 } 439 440 public void setOrientation(int orientation) { 441 if (orientation != HORIZONTAL && orientation != VERTICAL) { 442 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 443 return; 444 } 445 446 mOrientation = orientation; 447 mWindowAlignment.setOrientation(orientation); 448 mItemAlignment.setOrientation(orientation); 449 mForceFullLayout = true; 450 } 451 452 public int getFocusScrollStrategy() { 453 return mFocusScrollStrategy; 454 } 455 456 public void setFocusScrollStrategy(int focusScrollStrategy) { 457 mFocusScrollStrategy = focusScrollStrategy; 458 } 459 460 public void setWindowAlignment(int windowAlignment) { 461 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 462 } 463 464 public int getWindowAlignment() { 465 return mWindowAlignment.mainAxis().getWindowAlignment(); 466 } 467 468 public void setWindowAlignmentOffset(int alignmentOffset) { 469 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 470 } 471 472 public int getWindowAlignmentOffset() { 473 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 474 } 475 476 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 477 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 478 } 479 480 public float getWindowAlignmentOffsetPercent() { 481 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 482 } 483 484 public void setItemAlignmentOffset(int alignmentOffset) { 485 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 486 updateChildAlignments(); 487 } 488 489 public int getItemAlignmentOffset() { 490 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 491 } 492 493 public void setItemAlignmentOffsetPercent(float offsetPercent) { 494 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 495 updateChildAlignments(); 496 } 497 498 public float getItemAlignmentOffsetPercent() { 499 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 500 } 501 502 public void setItemAlignmentViewId(int viewId) { 503 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 504 updateChildAlignments(); 505 } 506 507 public int getItemAlignmentViewId() { 508 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 509 } 510 511 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 512 mFocusOutFront = throughFront; 513 mFocusOutEnd = throughEnd; 514 } 515 516 public void setNumRows(int numRows) { 517 if (numRows < 0) throw new IllegalArgumentException(); 518 mNumRowsRequested = numRows; 519 mForceFullLayout = true; 520 } 521 522 /** 523 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 524 */ 525 public void setRowHeight(int height) { 526 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 527 mRowSizeSecondaryRequested = height; 528 } else { 529 throw new IllegalArgumentException("Invalid row height: " + height); 530 } 531 } 532 533 public void setItemMargin(int margin) { 534 mVerticalMargin = mHorizontalMargin = margin; 535 mMarginPrimary = mMarginSecondary = margin; 536 } 537 538 public void setVerticalMargin(int margin) { 539 if (mOrientation == HORIZONTAL) { 540 mMarginSecondary = mVerticalMargin = margin; 541 } else { 542 mMarginPrimary = mVerticalMargin = margin; 543 } 544 } 545 546 public void setHorizontalMargin(int margin) { 547 if (mOrientation == HORIZONTAL) { 548 mMarginPrimary = mHorizontalMargin = margin; 549 } else { 550 mMarginSecondary = mHorizontalMargin = margin; 551 } 552 } 553 554 public int getVerticalMargin() { 555 return mVerticalMargin; 556 } 557 558 public int getHorizontalMargin() { 559 return mHorizontalMargin; 560 } 561 562 public void setGravity(int gravity) { 563 mGravity = gravity; 564 } 565 566 protected boolean hasDoneFirstLayout() { 567 return mGrid != null; 568 } 569 570 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 571 mChildSelectedListener = listener; 572 } 573 574 private int getPositionByView(View view) { 575 return getPositionByIndex(mBaseGridView.indexOfChild(view)); 576 } 577 578 private int getPositionByIndex(int index) { 579 if (index < 0) { 580 return NO_POSITION; 581 } 582 return mFirstVisiblePos + index; 583 } 584 585 private View getViewByPosition(int position) { 586 int index = getIndexByPosition(position); 587 if (index < 0) { 588 return null; 589 } 590 return getChildAt(index); 591 } 592 593 private int getIndexByPosition(int position) { 594 if (mFirstVisiblePos < 0 || 595 position < mFirstVisiblePos || position > mLastVisiblePos) { 596 return NO_POSITION; 597 } 598 return position - mFirstVisiblePos; 599 } 600 601 private void dispatchChildSelected() { 602 if (mChildSelectedListener == null) { 603 return; 604 } 605 606 View view = getViewByPosition(mFocusPosition); 607 608 if (mFocusPosition != NO_POSITION) { 609 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 610 mAdapter.getItemId(mFocusPosition)); 611 } else { 612 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 613 } 614 } 615 616 @Override 617 public boolean canScrollHorizontally() { 618 // We can scroll horizontally if we have horizontal orientation, or if 619 // we are vertical and have more than one column. 620 return mOrientation == HORIZONTAL || mNumRows > 1; 621 } 622 623 @Override 624 public boolean canScrollVertically() { 625 // We can scroll vertically if we have vertical orientation, or if we 626 // are horizontal and have more than one row. 627 return mOrientation == VERTICAL || mNumRows > 1; 628 } 629 630 @Override 631 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 632 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 633 ViewGroup.LayoutParams.WRAP_CONTENT); 634 } 635 636 @Override 637 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 638 return new LayoutParams(context, attrs); 639 } 640 641 @Override 642 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 643 if (lp instanceof LayoutParams) { 644 return new LayoutParams((LayoutParams) lp); 645 } else if (lp instanceof RecyclerView.LayoutParams) { 646 return new LayoutParams((RecyclerView.LayoutParams) lp); 647 } else if (lp instanceof MarginLayoutParams) { 648 return new LayoutParams((MarginLayoutParams) lp); 649 } else { 650 return new LayoutParams(lp); 651 } 652 } 653 654 protected View getViewForPosition(int position) { 655 View v = mRecycler.getViewForPosition(mAdapter, position); 656 if (v != null) { 657 ((LayoutParams) v.getLayoutParams()).onViewAttached(mInLayout); 658 } 659 return v; 660 } 661 662 final int getOpticalLeft(View v) { 663 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 664 } 665 666 final int getOpticalRight(View v) { 667 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 668 } 669 670 final int getOpticalTop(View v) { 671 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 672 } 673 674 final int getOpticalBottom(View v) { 675 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 676 } 677 678 private int getViewMin(View v) { 679 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 680 } 681 682 private int getViewMax(View v) { 683 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 684 } 685 686 private int getViewCenter(View view) { 687 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 688 } 689 690 private int getViewCenterSecondary(View view) { 691 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 692 } 693 694 private int getViewCenterX(View v) { 695 LayoutParams p = (LayoutParams) v.getLayoutParams(); 696 return p.getOpticalLeft(v) + p.getAlignX(); 697 } 698 699 private int getViewCenterY(View v) { 700 LayoutParams p = (LayoutParams) v.getLayoutParams(); 701 return p.getOpticalTop(v) + p.getAlignY(); 702 } 703 704 private void setViewLayoutForward(View v, boolean layoutForward) { 705 LayoutParams p = (LayoutParams) v.getLayoutParams(); 706 p.mLayoutForward = layoutForward; 707 } 708 709 private boolean getIsViewLayoutForward(View v) { 710 return ((LayoutParams) v.getLayoutParams()).mLayoutForward; 711 } 712 713 /** 714 * Re-initialize data structures for a data change or handling invisible 715 * selection. The method tries its best to preserve position information so 716 * that staggered grid looks same before and after re-initialize. 717 * @param focusPosition The initial focusPosition that we would like to 718 * focus on. 719 * @return Actual position that can be focused on. 720 */ 721 private int init(RecyclerView.Adapter adapter, RecyclerView.Recycler recycler, 722 int focusPosition) { 723 724 final int newItemCount = adapter.getItemCount(); 725 726 if (focusPosition == NO_POSITION && newItemCount > 0) { 727 // if focus position is never set before, initialize it to 0 728 focusPosition = 0; 729 } 730 // If adapter has changed then caches are invalid; otherwise, 731 // we try to maintain each row's position if number of rows keeps the same 732 // and existing mGrid contains the focusPosition. 733 if (mRows != null && mNumRows == mRows.length && 734 mGrid != null && mGrid.getSize() > 0 && focusPosition >= 0 && 735 focusPosition >= mGrid.getFirstIndex() && 736 focusPosition <= mGrid.getLastIndex()) { 737 // strip mGrid to a subset (like a column) that contains focusPosition 738 mGrid.stripDownTo(focusPosition); 739 // make sure that remaining items do not exceed new adapter size 740 int firstIndex = mGrid.getFirstIndex(); 741 int lastIndex = mGrid.getLastIndex(); 742 if (DEBUG) { 743 Log .v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " + lastIndex); 744 } 745 for (int i = lastIndex; i >=firstIndex; i--) { 746 if (i >= newItemCount) { 747 mGrid.removeLast(); 748 } 749 } 750 if (mGrid.getSize() == 0) { 751 focusPosition = newItemCount - 1; 752 // initialize row start locations 753 for (int i = 0; i < mNumRows; i++) { 754 mRows[i].low = 0; 755 mRows[i].high = 0; 756 } 757 if (DEBUG) Log.v(getTag(), "mGrid zero size"); 758 } else { 759 // initialize row start locations 760 for (int i = 0; i < mNumRows; i++) { 761 mRows[i].low = Integer.MAX_VALUE; 762 mRows[i].high = Integer.MIN_VALUE; 763 } 764 firstIndex = mGrid.getFirstIndex(); 765 lastIndex = mGrid.getLastIndex(); 766 if (focusPosition > lastIndex) { 767 focusPosition = mGrid.getLastIndex(); 768 } 769 if (DEBUG) { 770 Log.v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " 771 + lastIndex + " focusPosition " + focusPosition); 772 } 773 // fill rows with minimal view positions of the subset 774 for (int i = firstIndex; i <= lastIndex; i++) { 775 View v = getViewByPosition(i); 776 if (v == null) { 777 continue; 778 } 779 int row = mGrid.getLocation(i).row; 780 int low = getViewMin(v) + mScrollOffsetPrimary; 781 if (low < mRows[row].low) { 782 mRows[row].low = mRows[row].high = low; 783 } 784 } 785 // fill other rows that does not include the subset using first item 786 int firstItemRowPosition = mRows[mGrid.getLocation(firstIndex).row].low; 787 if (firstItemRowPosition == Integer.MAX_VALUE) { 788 firstItemRowPosition = 0; 789 } 790 for (int i = 0; i < mNumRows; i++) { 791 if (mRows[i].low == Integer.MAX_VALUE) { 792 mRows[i].low = mRows[i].high = firstItemRowPosition; 793 } 794 } 795 } 796 797 // Same adapter, we can reuse any attached views 798 detachAndScrapAttachedViews(recycler); 799 800 } else { 801 // otherwise recreate data structure 802 mRows = new StaggeredGrid.Row[mNumRows]; 803 mRowSizeSecondary = new int[mNumRows]; 804 805 for (int i = 0; i < mNumRows; i++) { 806 mRows[i] = new StaggeredGrid.Row(); 807 } 808 mGrid = new StaggeredGridDefault(); 809 if (newItemCount == 0) { 810 focusPosition = NO_POSITION; 811 } else if (focusPosition >= newItemCount) { 812 focusPosition = newItemCount - 1; 813 } 814 815 // Adapter may have changed so remove all attached views permanently 816 removeAllViews(); 817 818 mScrollOffsetPrimary = 0; 819 mScrollOffsetSecondary = 0; 820 mWindowAlignment.reset(); 821 } 822 823 mAdapter = adapter; 824 mRecycler = recycler; 825 mGrid.setProvider(mGridProvider); 826 // mGrid share the same Row array information 827 mGrid.setRows(mRows); 828 mFirstVisiblePos = mLastVisiblePos = NO_POSITION; 829 830 initScrollController(); 831 updateScrollSecondAxis(); 832 833 return focusPosition; 834 } 835 836 private int getRowSizeSecondary(int rowIndex) { 837 if (mFixedRowSizeSecondary != 0) { 838 return mFixedRowSizeSecondary; 839 } 840 if (mRowSizeSecondary == null) { 841 return 0; 842 } 843 return mRowSizeSecondary[rowIndex]; 844 } 845 846 private int getRowStartSecondary(int rowIndex) { 847 int start = 0; 848 for (int i = 0; i < rowIndex; i++) { 849 start += getRowSizeSecondary(i) + mMarginSecondary; 850 } 851 return start; 852 } 853 854 private int getSizeSecondary() { 855 return getRowStartSecondary(mNumRows - 1) + getRowSizeSecondary(mNumRows - 1); 856 } 857 858 private boolean processRowSizeSecondary(boolean measure) { 859 if (mFixedRowSizeSecondary != 0) { 860 return false; 861 } 862 863 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 864 boolean changed = false; 865 866 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 867 int rowSize = 0; 868 869 final int rowItemCount = rows[rowIndex].size(); 870 if (DEBUG) Log.v(getTag(), "processRowSizeSecondary row " + rowIndex + 871 " rowItemCount " + rowItemCount); 872 873 for (int i = 0; i < rowItemCount; i++) { 874 final int position = rows[rowIndex].get(i); 875 final View view = getViewByPosition(position); 876 if (measure && view.isLayoutRequested()) { 877 measureChild(view, rowIndex); 878 } 879 // If this view isn't visible, we ignore it. 880 if (getOpticalRight(view) < 0 || getOpticalLeft(view) > getWidth() || 881 getOpticalBottom(view) < 0 || getOpticalTop(view) > getHeight()) { 882 continue; 883 } 884 final int secondarySize = mOrientation == HORIZONTAL ? 885 view.getMeasuredHeight() : view.getMeasuredWidth(); 886 if (secondarySize > rowSize) { 887 rowSize = secondarySize; 888 } 889 } 890 if (DEBUG) Log.v(getTag(), "row " + rowIndex + " rowItemCount " + rowItemCount + 891 " rowSize " + rowSize); 892 893 if (mRowSizeSecondary[rowIndex] != rowSize) { 894 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 895 ", " + rowSize); 896 897 mRowSizeSecondary[rowIndex] = rowSize; 898 changed = true; 899 } 900 } 901 902 return changed; 903 } 904 905 /** 906 * Checks if we need to update row secondary sizes. 907 */ 908 private void updateRowSecondarySizeRefresh() { 909 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 910 if (mRowSecondarySizeRefresh) { 911 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 912 forceRequestLayout(); 913 } 914 } 915 916 private void forceRequestLayout() { 917 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 918 // RecyclerView prevents us from requesting layout in many cases 919 // (during layout, during scroll, etc.) 920 // For secondary row size wrap_content support we currently need a 921 // second layout pass to update the measured size after having measured 922 // and added child views in layoutChildren. 923 // Force the second layout by posting a delayed runnable. 924 // TODO: investigate allowing a second layout pass, 925 // or move child add/measure logic to the measure phase. 926 mBaseGridView.getHandler().post(new Runnable() { 927 @Override 928 public void run() { 929 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 930 requestLayout(); 931 } 932 }); 933 } 934 935 @Override 936 public void onMeasure(int widthSpec, int heightSpec) { 937 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 938 int measuredSizeSecondary; 939 if (mOrientation == HORIZONTAL) { 940 sizePrimary = MeasureSpec.getSize(widthSpec); 941 sizeSecondary = MeasureSpec.getSize(heightSpec); 942 modeSecondary = MeasureSpec.getMode(heightSpec); 943 paddingSecondary = getPaddingTop() + getPaddingBottom(); 944 } else { 945 sizeSecondary = MeasureSpec.getSize(widthSpec); 946 sizePrimary = MeasureSpec.getSize(heightSpec); 947 modeSecondary = MeasureSpec.getMode(widthSpec); 948 paddingSecondary = getPaddingLeft() + getPaddingRight(); 949 } 950 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 951 " heightSpec " + Integer.toHexString(heightSpec) + 952 " modeSecondary " + Integer.toHexString(modeSecondary) + 953 " sizeSecondary " + sizeSecondary + " " + this); 954 955 mMaxSizeSecondary = sizeSecondary; 956 957 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 958 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 959 mFixedRowSizeSecondary = 0; 960 961 // Measure all current children and update cached row heights 962 if (mGrid != null) { 963 processRowSizeSecondary(true); 964 } 965 966 switch (modeSecondary) { 967 case MeasureSpec.UNSPECIFIED: 968 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 969 break; 970 case MeasureSpec.AT_MOST: 971 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 972 mMaxSizeSecondary); 973 break; 974 case MeasureSpec.EXACTLY: 975 measuredSizeSecondary = mMaxSizeSecondary; 976 break; 977 default: 978 throw new IllegalStateException("wrong spec"); 979 } 980 981 } else { 982 switch (modeSecondary) { 983 case MeasureSpec.UNSPECIFIED: 984 if (mRowSizeSecondaryRequested == 0) { 985 if (mOrientation == HORIZONTAL) { 986 throw new IllegalStateException("Must specify rowHeight or view height"); 987 } else { 988 throw new IllegalStateException("Must specify columnWidth or view width"); 989 } 990 } 991 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 992 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 993 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 994 * (mNumRows - 1) + paddingSecondary; 995 break; 996 case MeasureSpec.AT_MOST: 997 case MeasureSpec.EXACTLY: 998 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 999 mNumRows = 1; 1000 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 1001 } else if (mNumRowsRequested == 0) { 1002 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1003 mNumRows = (sizeSecondary + mMarginSecondary) 1004 / (mRowSizeSecondaryRequested + mMarginSecondary); 1005 } else if (mRowSizeSecondaryRequested == 0) { 1006 mNumRows = mNumRowsRequested; 1007 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 1008 * (mNumRows - 1)) / mNumRows; 1009 } else { 1010 mNumRows = mNumRowsRequested; 1011 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1012 } 1013 measuredSizeSecondary = sizeSecondary; 1014 if (modeSecondary == MeasureSpec.AT_MOST) { 1015 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1016 * (mNumRows - 1) + paddingSecondary; 1017 if (childrenSize < measuredSizeSecondary) { 1018 measuredSizeSecondary = childrenSize; 1019 } 1020 } 1021 break; 1022 default: 1023 throw new IllegalStateException("wrong spec"); 1024 } 1025 } 1026 if (mOrientation == HORIZONTAL) { 1027 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1028 } else { 1029 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1030 } 1031 if (DEBUG) { 1032 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1033 " measuredSizeSecondary " + measuredSizeSecondary + 1034 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1035 " mNumRows " + mNumRows); 1036 } 1037 } 1038 1039 private void measureChild(View child, int rowIndex) { 1040 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1041 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1042 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1043 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1044 int widthSpec, heightSpec; 1045 1046 if (mOrientation == HORIZONTAL) { 1047 widthSpec = ViewGroup.getChildMeasureSpec( 1048 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1049 0, lp.width); 1050 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1051 } else { 1052 heightSpec = ViewGroup.getChildMeasureSpec( 1053 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1054 0, lp.height); 1055 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1056 } 1057 1058 child.measure(widthSpec, heightSpec); 1059 1060 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1061 " widthSpec " + Integer.toHexString(widthSpec) + 1062 " heightSpec " + Integer.toHexString(heightSpec) + 1063 " measuredWidth " + child.getMeasuredWidth() + 1064 " measuredHeight " + child.getMeasuredHeight()); 1065 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1066 } 1067 1068 private StaggeredGrid.Provider mGridProvider = new StaggeredGrid.Provider() { 1069 1070 @Override 1071 public int getCount() { 1072 return mAdapter.getItemCount(); 1073 } 1074 1075 @Override 1076 public void createItem(int index, int rowIndex, boolean append) { 1077 View v = getViewForPosition(index); 1078 if (mFirstVisiblePos >= 0) { 1079 // when StaggeredGrid append or prepend item, we must guarantee 1080 // that sibling item has created views already. 1081 if (append && index != mLastVisiblePos + 1) { 1082 throw new RuntimeException(); 1083 } else if (!append && index != mFirstVisiblePos - 1) { 1084 throw new RuntimeException(); 1085 } 1086 } 1087 1088 if (append) { 1089 addView(v); 1090 } else { 1091 addView(v, 0); 1092 } 1093 1094 measureChild(v, rowIndex); 1095 1096 int length = mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1097 int start, end; 1098 if (append) { 1099 start = mRows[rowIndex].high; 1100 if (start != mRows[rowIndex].low) { 1101 // if there are existing item in the row, add margin between 1102 start += mMarginPrimary; 1103 } else { 1104 final int lastRow = mRows.length - 1; 1105 if (lastRow != rowIndex && mRows[lastRow].high != mRows[lastRow].low) { 1106 // if there are existing item in the last row, insert 1107 // the new item after the last item of last row. 1108 start = mRows[lastRow].high + mMarginPrimary; 1109 } 1110 } 1111 end = start + length; 1112 mRows[rowIndex].high = end; 1113 } else { 1114 end = mRows[rowIndex].low; 1115 if (end != mRows[rowIndex].high) { 1116 end -= mMarginPrimary; 1117 } else if (0 != rowIndex && mRows[0].high != mRows[0].low) { 1118 // if there are existing item in the first row, insert 1119 // the new item before the first item of first row. 1120 end = mRows[0].low - mMarginPrimary; 1121 } 1122 start = end - length; 1123 mRows[rowIndex].low = start; 1124 } 1125 if (mFirstVisiblePos < 0) { 1126 mFirstVisiblePos = mLastVisiblePos = index; 1127 } else { 1128 if (append) { 1129 mLastVisiblePos++; 1130 } else { 1131 mFirstVisiblePos--; 1132 } 1133 } 1134 if (DEBUG) Log.v(getTag(), "start " + start + " end " + end); 1135 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1136 layoutChild(rowIndex, v, start - mScrollOffsetPrimary, end - mScrollOffsetPrimary, 1137 startSecondary); 1138 if (DEBUG) { 1139 Log.d(getTag(), "addView " + index + " " + v); 1140 } 1141 updateScrollMin(); 1142 updateScrollMax(); 1143 1144 setViewLayoutForward(v, append); 1145 } 1146 }; 1147 1148 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1149 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1150 : v.getMeasuredWidth(); 1151 if (mFixedRowSizeSecondary > 0) { 1152 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1153 } 1154 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1155 final int horizontalGravity = mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1156 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1157 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1158 // do nothing 1159 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1160 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1161 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1162 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1163 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1164 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1165 } 1166 int left, top, right, bottom; 1167 if (mOrientation == HORIZONTAL) { 1168 left = start; 1169 top = startSecondary; 1170 right = end; 1171 bottom = startSecondary + sizeSecondary; 1172 } else { 1173 top = start; 1174 left = startSecondary; 1175 bottom = end; 1176 right = startSecondary + sizeSecondary; 1177 } 1178 v.layout(left, top, right, bottom); 1179 updateChildOpticalInsets(v, left, top, right, bottom); 1180 updateChildAlignments(v); 1181 } 1182 1183 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1184 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1185 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1186 v.getRight() - right, v.getBottom() - bottom); 1187 } 1188 1189 private void updateChildAlignments(View v) { 1190 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1191 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1192 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1193 } 1194 1195 private void updateChildAlignments() { 1196 for (int i = 0, c = getChildCount(); i < c; i++) { 1197 updateChildAlignments(getChildAt(i)); 1198 } 1199 } 1200 1201 private boolean needsAppendVisibleItem() { 1202 if (mLastVisiblePos < mFocusPosition) { 1203 return true; 1204 } 1205 int right = mScrollOffsetPrimary + mSizePrimary; 1206 for (int i = 0; i < mNumRows; i++) { 1207 if (mRows[i].low == mRows[i].high) { 1208 if (mRows[i].high < right) { 1209 return true; 1210 } 1211 } else if (mRows[i].high < right - mMarginPrimary) { 1212 return true; 1213 } 1214 } 1215 return false; 1216 } 1217 1218 private boolean needsPrependVisibleItem() { 1219 if (mFirstVisiblePos > mFocusPosition) { 1220 return true; 1221 } 1222 for (int i = 0; i < mNumRows; i++) { 1223 if (mRows[i].low == mRows[i].high) { 1224 if (mRows[i].low > mScrollOffsetPrimary) { 1225 return true; 1226 } 1227 } else if (mRows[i].low - mMarginPrimary > mScrollOffsetPrimary) { 1228 return true; 1229 } 1230 } 1231 return false; 1232 } 1233 1234 // Append one column if possible and return true if reach end. 1235 private boolean appendOneVisibleItem() { 1236 while (true) { 1237 if (mLastVisiblePos != NO_POSITION && mLastVisiblePos < mAdapter.getItemCount() -1 && 1238 mLastVisiblePos < mGrid.getLastIndex()) { 1239 // append invisible view of saved location till last row 1240 final int index = mLastVisiblePos + 1; 1241 final int row = mGrid.getLocation(index).row; 1242 mGridProvider.createItem(index, row, true); 1243 if (row == mNumRows - 1) { 1244 return false; 1245 } 1246 } else if ((mLastVisiblePos == NO_POSITION && mAdapter.getItemCount() > 0) || 1247 (mLastVisiblePos != NO_POSITION && 1248 mLastVisiblePos < mAdapter.getItemCount() - 1)) { 1249 mGrid.appendItems(mScrollOffsetPrimary + mSizePrimary); 1250 return false; 1251 } else { 1252 return true; 1253 } 1254 } 1255 } 1256 1257 private void appendVisibleItems() { 1258 while (needsAppendVisibleItem()) { 1259 if (appendOneVisibleItem()) { 1260 break; 1261 } 1262 } 1263 } 1264 1265 // Prepend one column if possible and return true if reach end. 1266 private boolean prependOneVisibleItem() { 1267 while (true) { 1268 if (mFirstVisiblePos > 0) { 1269 if (mFirstVisiblePos > mGrid.getFirstIndex()) { 1270 // prepend invisible view of saved location till first row 1271 final int index = mFirstVisiblePos - 1; 1272 final int row = mGrid.getLocation(index).row; 1273 mGridProvider.createItem(index, row, false); 1274 if (row == 0) { 1275 return false; 1276 } 1277 } else { 1278 mGrid.prependItems(mScrollOffsetPrimary); 1279 return false; 1280 } 1281 } else { 1282 return true; 1283 } 1284 } 1285 } 1286 1287 private void prependVisibleItems() { 1288 while (needsPrependVisibleItem()) { 1289 if (prependOneVisibleItem()) { 1290 break; 1291 } 1292 } 1293 } 1294 1295 private void removeChildAt(int position) { 1296 View v = getViewByPosition(position); 1297 if (v != null) { 1298 if (DEBUG) { 1299 Log.d(getTag(), "removeAndRecycleViewAt " + position); 1300 } 1301 ((LayoutParams) v.getLayoutParams()).onViewDetached(); 1302 removeAndRecycleViewAt(getIndexByPosition(position), mRecycler); 1303 } 1304 } 1305 1306 private void removeInvisibleViewsAtEnd() { 1307 if (!mPruneChild) { 1308 return; 1309 } 1310 boolean update = false; 1311 while(mLastVisiblePos > mFirstVisiblePos && mLastVisiblePos > mFocusPosition) { 1312 View view = getViewByPosition(mLastVisiblePos); 1313 if (getViewMin(view) > mSizePrimary) { 1314 removeChildAt(mLastVisiblePos); 1315 mLastVisiblePos--; 1316 update = true; 1317 } else { 1318 break; 1319 } 1320 } 1321 if (update) { 1322 updateRowsMinMax(); 1323 } 1324 } 1325 1326 private void removeInvisibleViewsAtFront() { 1327 if (!mPruneChild) { 1328 return; 1329 } 1330 boolean update = false; 1331 while(mLastVisiblePos > mFirstVisiblePos && mFirstVisiblePos < mFocusPosition) { 1332 View view = getViewByPosition(mFirstVisiblePos); 1333 if (getViewMax(view) < 0) { 1334 removeChildAt(mFirstVisiblePos); 1335 mFirstVisiblePos++; 1336 update = true; 1337 } else { 1338 break; 1339 } 1340 } 1341 if (update) { 1342 updateRowsMinMax(); 1343 } 1344 } 1345 1346 private void updateRowsMinMax() { 1347 if (mFirstVisiblePos < 0) { 1348 return; 1349 } 1350 for (int i = 0; i < mNumRows; i++) { 1351 mRows[i].low = Integer.MAX_VALUE; 1352 mRows[i].high = Integer.MIN_VALUE; 1353 } 1354 for (int i = mFirstVisiblePos; i <= mLastVisiblePos; i++) { 1355 View view = getViewByPosition(i); 1356 int row = mGrid.getLocation(i).row; 1357 int low = getViewMin(view) + mScrollOffsetPrimary; 1358 if (low < mRows[row].low) { 1359 mRows[row].low = low; 1360 } 1361 int high = getViewMax(view) + mScrollOffsetPrimary; 1362 if (high > mRows[row].high) { 1363 mRows[row].high = high; 1364 } 1365 } 1366 } 1367 1368 // Fast layout when there is no structure change, adapter change, etc. 1369 protected void fastRelayout() { 1370 initScrollController(); 1371 1372 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 1373 1374 // relayout and repositioning views on each row 1375 for (int i = 0; i < mNumRows; i++) { 1376 List<Integer> row = rows[i]; 1377 final int startSecondary = getRowStartSecondary(i) - mScrollOffsetSecondary; 1378 for (int j = 0, size = row.size(); j < size; j++) { 1379 final int position = row.get(j); 1380 final View view = getViewByPosition(position); 1381 final boolean layoutForward = getIsViewLayoutForward(view); 1382 int primaryDelta, start, end; 1383 1384 if (mOrientation == HORIZONTAL) { 1385 final int primarySize = view.getMeasuredWidth(); 1386 if (view.isLayoutRequested()) { 1387 measureChild(view, i); 1388 } 1389 if (layoutForward) { 1390 start = getViewMin(view); 1391 end = start + view.getMeasuredWidth(); 1392 primaryDelta = view.getMeasuredWidth() - primarySize; 1393 if (primaryDelta != 0) { 1394 for (int k = j + 1; k < size; k++) { 1395 getViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1396 } 1397 } 1398 } else { 1399 end = getViewMax(view); 1400 start = end - view.getMeasuredWidth(); 1401 primaryDelta = primarySize - view.getMeasuredWidth(); 1402 if (primaryDelta != 0) { 1403 for (int k = 0; k < j; k++) { 1404 getViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1405 } 1406 } 1407 } 1408 } else { 1409 final int primarySize = view.getMeasuredHeight(); 1410 if (view.isLayoutRequested()) { 1411 measureChild(view, i); 1412 } 1413 if (layoutForward) { 1414 start = getViewMin(view); 1415 end = start + view.getMeasuredHeight(); 1416 primaryDelta = view.getMeasuredHeight() - primarySize; 1417 if (primaryDelta != 0) { 1418 for (int k = j + 1; k < size; k++) { 1419 getViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1420 } 1421 } 1422 } else { 1423 end = getViewMax(view); 1424 start = end - view.getMeasuredHeight(); 1425 primaryDelta = primarySize - view.getMeasuredHeight(); 1426 if (primaryDelta != 0) { 1427 for (int k = 0; k < j; k++) { 1428 getViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1429 } 1430 } 1431 } 1432 } 1433 layoutChild(i, view, start, end, startSecondary); 1434 } 1435 } 1436 1437 updateRowsMinMax(); 1438 appendVisibleItems(); 1439 prependVisibleItems(); 1440 1441 updateRowsMinMax(); 1442 updateScrollMin(); 1443 updateScrollMax(); 1444 updateScrollSecondAxis(); 1445 1446 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1447 View focusView = getViewByPosition(mFocusPosition == NO_POSITION ? 0 : mFocusPosition); 1448 scrollToView(focusView, false); 1449 } 1450 } 1451 1452 // Lays out items based on the current scroll position 1453 @Override 1454 public void onLayoutChildren(RecyclerView.Adapter adapter, RecyclerView.Recycler recycler, 1455 boolean structureChanged, RecyclerView.State state) { 1456 if (DEBUG) { 1457 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1458 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1459 + " structureChanged " + structureChanged 1460 + " mForceFullLayout " + mForceFullLayout); 1461 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1462 } 1463 1464 if (mNumRows == 0) { 1465 // haven't done measure yet 1466 return; 1467 } 1468 final int itemCount = adapter.getItemCount(); 1469 if (itemCount < 0) { 1470 return; 1471 } 1472 1473 if (!mLayoutEnabled) { 1474 discardLayoutInfo(); 1475 removeAllViews(); 1476 return; 1477 } 1478 mInLayout = true; 1479 1480 attemptRecordChildLayout(); 1481 // Track the old focus view so we can adjust our system scroll position 1482 // so that any scroll animations happening now will remain valid. 1483 int delta = 0, deltaSecondary = 0; 1484 if (mFocusPosition != NO_POSITION 1485 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1486 View focusView = getViewByPosition(mFocusPosition); 1487 if (focusView != null) { 1488 delta = mWindowAlignment.mainAxis().getSystemScrollPos( 1489 getViewCenter(focusView) + mScrollOffsetPrimary) - mScrollOffsetPrimary; 1490 deltaSecondary = 1491 mWindowAlignment.secondAxis().getSystemScrollPos( 1492 getViewCenterSecondary(focusView) + mScrollOffsetSecondary) 1493 - mScrollOffsetSecondary; 1494 } 1495 } 1496 1497 final boolean hasDoneFirstLayout = hasDoneFirstLayout(); 1498 if (!structureChanged && !mForceFullLayout && hasDoneFirstLayout) { 1499 fastRelayout(); 1500 } else { 1501 boolean hadFocus = mBaseGridView.hasFocus(); 1502 1503 int newFocusPosition = init(adapter, recycler, mFocusPosition); 1504 if (DEBUG) { 1505 Log.v(getTag(), "mFocusPosition " + mFocusPosition + " newFocusPosition " 1506 + newFocusPosition); 1507 } 1508 1509 // depending on result of init(), either recreating everything 1510 // or try to reuse the row start positions near mFocusPosition 1511 if (mGrid.getSize() == 0) { 1512 // this is a fresh creating all items, starting from 1513 // mFocusPosition with a estimated row index. 1514 mGrid.setStart(newFocusPosition, StaggeredGrid.START_DEFAULT); 1515 1516 // Can't track the old focus view 1517 delta = deltaSecondary = 0; 1518 1519 } else { 1520 // mGrid remembers Locations for the column that 1521 // contains mFocusePosition and also mRows remembers start 1522 // positions of each row. 1523 // Manually re-create child views for that column 1524 int firstIndex = mGrid.getFirstIndex(); 1525 int lastIndex = mGrid.getLastIndex(); 1526 for (int i = firstIndex; i <= lastIndex; i++) { 1527 mGridProvider.createItem(i, mGrid.getLocation(i).row, true); 1528 } 1529 } 1530 // add visible views at end until reach the end of window 1531 appendVisibleItems(); 1532 // add visible views at front until reach the start of window 1533 prependVisibleItems(); 1534 // multiple rounds: scrollToView of first round may drag first/last child into 1535 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1536 int oldFirstVisible; 1537 int oldLastVisible; 1538 do { 1539 oldFirstVisible = mFirstVisiblePos; 1540 oldLastVisible = mLastVisiblePos; 1541 View focusView = getViewByPosition(newFocusPosition); 1542 // we need force to initialize the child view's position 1543 scrollToView(focusView, false); 1544 if (focusView != null && hadFocus) { 1545 focusView.requestFocus(); 1546 } 1547 appendVisibleItems(); 1548 prependVisibleItems(); 1549 removeInvisibleViewsAtFront(); 1550 removeInvisibleViewsAtEnd(); 1551 } while (mFirstVisiblePos != oldFirstVisible || mLastVisiblePos != oldLastVisible); 1552 } 1553 mForceFullLayout = false; 1554 1555 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1556 scrollDirectionPrimary(-delta); 1557 scrollDirectionSecondary(-deltaSecondary); 1558 } 1559 appendVisibleItems(); 1560 prependVisibleItems(); 1561 removeInvisibleViewsAtFront(); 1562 removeInvisibleViewsAtEnd(); 1563 1564 if (DEBUG) { 1565 StringWriter sw = new StringWriter(); 1566 PrintWriter pw = new PrintWriter(sw); 1567 mGrid.debugPrint(pw); 1568 Log.d(getTag(), sw.toString()); 1569 } 1570 1571 removeAndRecycleScrap(recycler); 1572 attemptAnimateLayoutChild(); 1573 1574 if (mRowSecondarySizeRefresh) { 1575 mRowSecondarySizeRefresh = false; 1576 } else { 1577 updateRowSecondarySizeRefresh(); 1578 } 1579 1580 if (!hasDoneFirstLayout) { 1581 dispatchChildSelected(); 1582 } 1583 mInLayout = false; 1584 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1585 } 1586 1587 private void offsetChildrenSecondary(int increment) { 1588 final int childCount = getChildCount(); 1589 if (mOrientation == HORIZONTAL) { 1590 for (int i = 0; i < childCount; i++) { 1591 getChildAt(i).offsetTopAndBottom(increment); 1592 } 1593 } else { 1594 for (int i = 0; i < childCount; i++) { 1595 getChildAt(i).offsetLeftAndRight(increment); 1596 } 1597 } 1598 mScrollOffsetSecondary -= increment; 1599 } 1600 1601 private void offsetChildrenPrimary(int increment) { 1602 final int childCount = getChildCount(); 1603 if (mOrientation == VERTICAL) { 1604 for (int i = 0; i < childCount; i++) { 1605 getChildAt(i).offsetTopAndBottom(increment); 1606 } 1607 } else { 1608 for (int i = 0; i < childCount; i++) { 1609 getChildAt(i).offsetLeftAndRight(increment); 1610 } 1611 } 1612 mScrollOffsetPrimary -= increment; 1613 } 1614 1615 @Override 1616 public int scrollHorizontallyBy(int dx, Adapter adapter, Recycler recycler, 1617 RecyclerView.State state) { 1618 if (DEBUG) Log.v(TAG, "scrollHorizontallyBy " + dx); 1619 1620 if (mOrientation == HORIZONTAL) { 1621 return scrollDirectionPrimary(dx); 1622 } else { 1623 return scrollDirectionSecondary(dx); 1624 } 1625 } 1626 1627 @Override 1628 public int scrollVerticallyBy(int dy, Adapter adapter, Recycler recycler, 1629 RecyclerView.State state) { 1630 if (DEBUG) Log.v(TAG, "scrollVerticallyBy " + dy); 1631 if (mOrientation == VERTICAL) { 1632 return scrollDirectionPrimary(dy); 1633 } else { 1634 return scrollDirectionSecondary(dy); 1635 } 1636 } 1637 1638 // scroll in main direction may add/prune views 1639 private int scrollDirectionPrimary(int da) { 1640 offsetChildrenPrimary(-da); 1641 if (mInLayout) { 1642 return da; 1643 } 1644 1645 int childCount = getChildCount(); 1646 boolean updated; 1647 1648 if (da > 0) { 1649 appendVisibleItems(); 1650 } else if (da < 0) { 1651 prependVisibleItems(); 1652 } 1653 updated = getChildCount() > childCount; 1654 childCount = getChildCount(); 1655 1656 if (da > 0) { 1657 removeInvisibleViewsAtFront(); 1658 } else if (da < 0) { 1659 removeInvisibleViewsAtEnd(); 1660 } 1661 updated |= getChildCount() < childCount; 1662 1663 if (updated) { 1664 updateRowSecondarySizeRefresh(); 1665 } 1666 1667 mBaseGridView.invalidate(); 1668 return da; 1669 } 1670 1671 // scroll in second direction will not add/prune views 1672 private int scrollDirectionSecondary(int dy) { 1673 offsetChildrenSecondary(-dy); 1674 mBaseGridView.invalidate(); 1675 return dy; 1676 } 1677 1678 private void updateScrollMax() { 1679 if (mLastVisiblePos >= 0 && mLastVisiblePos == mAdapter.getItemCount() - 1) { 1680 int maxEdge = Integer.MIN_VALUE; 1681 for (int i = 0; i < mRows.length; i++) { 1682 if (mRows[i].high > maxEdge) { 1683 maxEdge = mRows[i].high; 1684 } 1685 } 1686 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1687 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge); 1688 } 1689 } 1690 1691 private void updateScrollMin() { 1692 if (mFirstVisiblePos == 0) { 1693 int minEdge = Integer.MAX_VALUE; 1694 for (int i = 0; i < mRows.length; i++) { 1695 if (mRows[i].low < minEdge) { 1696 minEdge = mRows[i].low; 1697 } 1698 } 1699 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1700 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge); 1701 } 1702 } 1703 1704 private void updateScrollSecondAxis() { 1705 mWindowAlignment.secondAxis().setMinEdge(0); 1706 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1707 } 1708 1709 private void initScrollController() { 1710 mWindowAlignment.horizontal.setSize(getWidth()); 1711 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1712 mWindowAlignment.vertical.setSize(getHeight()); 1713 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1714 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1715 mWindowAlignment.mainAxis().invalidateScrollMin(); 1716 mWindowAlignment.mainAxis().invalidateScrollMax(); 1717 1718 if (DEBUG) { 1719 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1720 + " mWindowAlignment " + mWindowAlignment); 1721 } 1722 } 1723 1724 public void setSelection(RecyclerView parent, int position) { 1725 setSelection(parent, position, false); 1726 } 1727 1728 public void setSelectionSmooth(RecyclerView parent, int position) { 1729 setSelection(parent, position, true); 1730 } 1731 1732 public int getSelection() { 1733 return mFocusPosition; 1734 } 1735 1736 public void setSelection(RecyclerView parent, int position, boolean smooth) { 1737 if (mFocusPosition == position) { 1738 return; 1739 } 1740 View view = getViewByPosition(position); 1741 if (view != null) { 1742 scrollToView(view, smooth); 1743 } else { 1744 boolean right = position > mFocusPosition; 1745 mFocusPosition = position; 1746 if (!mLayoutEnabled) { 1747 return; 1748 } 1749 if (smooth) { 1750 if (!hasDoneFirstLayout()) { 1751 Log.w(getTag(), "setSelectionSmooth should " + 1752 "not be called before first layout pass"); 1753 return; 1754 } 1755 if (right) { 1756 appendVisibleItems(); 1757 } else { 1758 prependVisibleItems(); 1759 } 1760 scrollToView(getViewByPosition(position), smooth); 1761 } else { 1762 mForceFullLayout = true; 1763 parent.requestLayout(); 1764 } 1765 } 1766 } 1767 1768 @Override 1769 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 1770 boolean needsLayout = false; 1771 if (itemCount != 0) { 1772 if (mFirstVisiblePos < 0) { 1773 needsLayout = true; 1774 } else if (!(positionStart > mLastVisiblePos + 1 || 1775 positionStart + itemCount < mFirstVisiblePos - 1)) { 1776 needsLayout = true; 1777 } 1778 } 1779 if (needsLayout) { 1780 recyclerView.requestLayout(); 1781 } 1782 } 1783 1784 @Override 1785 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 1786 if (mFocusSearchDisabled) { 1787 return true; 1788 } 1789 if (!mInLayout) { 1790 scrollToView(child, true); 1791 } 1792 return true; 1793 } 1794 1795 @Override 1796 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 1797 boolean immediate) { 1798 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 1799 return false; 1800 } 1801 1802 int getScrollOffsetX() { 1803 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 1804 } 1805 1806 int getScrollOffsetY() { 1807 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 1808 } 1809 1810 public void getViewSelectedOffsets(View view, int[] offsets) { 1811 int scrollOffsetX = getScrollOffsetX(); 1812 int scrollOffsetY = getScrollOffsetY(); 1813 int viewCenterX = scrollOffsetX + getViewCenterX(view); 1814 int viewCenterY = scrollOffsetY + getViewCenterY(view); 1815 offsets[0] = mWindowAlignment.horizontal.getSystemScrollPos(viewCenterX) - scrollOffsetX; 1816 offsets[1] = mWindowAlignment.vertical.getSystemScrollPos(viewCenterY) - scrollOffsetY; 1817 } 1818 1819 /** 1820 * Scroll to a given child view and change mFocusPosition. 1821 */ 1822 private void scrollToView(View view, boolean smooth) { 1823 int newFocusPosition = getPositionByView(view); 1824 if (mInLayout || newFocusPosition != mFocusPosition) { 1825 mFocusPosition = newFocusPosition; 1826 dispatchChildSelected(); 1827 } 1828 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 1829 mBaseGridView.invalidate(); 1830 } 1831 if (view == null) { 1832 return; 1833 } 1834 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 1835 // transfer focus to the child if it does not have focus yet (e.g. triggered 1836 // by setSelection()) 1837 view.requestFocus(); 1838 } 1839 switch (mFocusScrollStrategy) { 1840 case BaseGridView.FOCUS_SCROLL_ALIGNED: 1841 default: 1842 scrollToAlignedPosition(view, smooth); 1843 break; 1844 case BaseGridView.FOCUS_SCROLL_ITEM: 1845 case BaseGridView.FOCUS_SCROLL_PAGE: 1846 scrollItemOrPage(view, smooth); 1847 break; 1848 } 1849 } 1850 1851 private void scrollItemOrPage(View view, boolean smooth) { 1852 int pos = getPositionByView(view); 1853 int viewMin = getViewMin(view); 1854 int viewMax = getViewMax(view); 1855 // we either align "firstView" to left/top padding edge 1856 // or align "lastView" to right/bottom padding edge 1857 View firstView = null; 1858 View lastView = null; 1859 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 1860 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 1861 final int row = mGrid.getLocation(pos).row; 1862 if (viewMin < paddingLow) { 1863 // view enters low padding area: 1864 firstView = view; 1865 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1866 // scroll one "page" left/top, 1867 // align first visible item of the "page" at the low padding edge. 1868 while (!prependOneVisibleItem()) { 1869 List<Integer> positions = 1870 mGrid.getItemPositionsInRows(mFirstVisiblePos, pos)[row]; 1871 firstView = getViewByPosition(positions.get(0)); 1872 if (viewMax - getViewMin(firstView) > clientSize) { 1873 if (positions.size() > 1) { 1874 firstView = getViewByPosition(positions.get(1)); 1875 } 1876 break; 1877 } 1878 } 1879 } 1880 } else if (viewMax > clientSize + paddingLow) { 1881 // view enters high padding area: 1882 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1883 // scroll whole one page right/bottom, align view at the low padding edge. 1884 firstView = view; 1885 do { 1886 List<Integer> positions = 1887 mGrid.getItemPositionsInRows(pos, mLastVisiblePos)[row]; 1888 lastView = getViewByPosition(positions.get(positions.size() - 1)); 1889 if (getViewMax(lastView) - viewMin > clientSize) { 1890 lastView = null; 1891 break; 1892 } 1893 } while (!appendOneVisibleItem()); 1894 if (lastView != null) { 1895 // however if we reached end, we should align last view. 1896 firstView = null; 1897 } 1898 } else { 1899 lastView = view; 1900 } 1901 } 1902 int scrollPrimary = 0; 1903 int scrollSecondary = 0; 1904 if (firstView != null) { 1905 scrollPrimary = getViewMin(firstView) - paddingLow; 1906 } else if (lastView != null) { 1907 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 1908 } 1909 View secondaryAlignedView; 1910 if (firstView != null) { 1911 secondaryAlignedView = firstView; 1912 } else if (lastView != null) { 1913 secondaryAlignedView = lastView; 1914 } else { 1915 secondaryAlignedView = view; 1916 } 1917 int viewCenterSecondary = mScrollOffsetSecondary + 1918 getViewCenterSecondary(secondaryAlignedView); 1919 mWindowAlignment.secondAxis().updateScrollCenter(viewCenterSecondary); 1920 scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(); 1921 scrollSecondary -= mScrollOffsetSecondary; 1922 scrollGrid(scrollPrimary, scrollSecondary, smooth); 1923 } 1924 1925 private void scrollToAlignedPosition(View view, boolean smooth) { 1926 int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 1927 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 1928 if (DEBUG) { 1929 Log.v(getTag(), "scrollAligned smooth=" + smooth + " pos=" + mFocusPosition + " " 1930 + viewCenterPrimary +","+viewCenterSecondary + " " + mWindowAlignment); 1931 } 1932 1933 if (mInLayout || viewCenterPrimary != mWindowAlignment.mainAxis().getScrollCenter() 1934 || viewCenterSecondary != mWindowAlignment.secondAxis().getScrollCenter()) { 1935 mWindowAlignment.mainAxis().updateScrollCenter(viewCenterPrimary); 1936 mWindowAlignment.secondAxis().updateScrollCenter(viewCenterSecondary); 1937 int scrollPrimary = mWindowAlignment.mainAxis().getSystemScrollPos(); 1938 int scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(); 1939 if (DEBUG) { 1940 Log.v(getTag(), "scrollAligned " + scrollPrimary + " " + scrollSecondary 1941 +" " + mWindowAlignment); 1942 } 1943 1944 scrollPrimary -= mScrollOffsetPrimary; 1945 scrollSecondary -= mScrollOffsetSecondary; 1946 1947 scrollGrid(scrollPrimary, scrollSecondary, smooth); 1948 } 1949 } 1950 1951 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 1952 if (mInLayout) { 1953 scrollDirectionPrimary(scrollPrimary); 1954 scrollDirectionSecondary(scrollSecondary); 1955 } else { 1956 int scrollX; 1957 int scrollY; 1958 if (mOrientation == HORIZONTAL) { 1959 scrollX = scrollPrimary; 1960 scrollY = scrollSecondary; 1961 } else { 1962 scrollX = scrollSecondary; 1963 scrollY = scrollPrimary; 1964 } 1965 if (smooth) { 1966 mBaseGridView.smoothScrollBy(scrollX, scrollY); 1967 } else { 1968 mBaseGridView.scrollBy(scrollX, scrollY); 1969 } 1970 } 1971 } 1972 1973 public void setAnimateChildLayout(boolean animateChildLayout) { 1974 mAnimateChildLayout = animateChildLayout; 1975 for (int i = 0, c = getChildCount(); i < c; i++) { 1976 View v = getChildAt(i); 1977 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1978 if (!mAnimateChildLayout) { 1979 p.endAnimate(); 1980 } 1981 } 1982 } 1983 1984 private void attemptRecordChildLayout() { 1985 if (!mAnimateChildLayout) { 1986 return; 1987 } 1988 for (int i = 0, c = getChildCount(); i < c; i++) { 1989 View v = getChildAt(i); 1990 ((LayoutParams) v.getLayoutParams()).recordStart(mOrientation, v); 1991 } 1992 } 1993 1994 private void attemptAnimateLayoutChild() { 1995 if (!mAnimateChildLayout) { 1996 return; 1997 } 1998 for (int i = 0, c = getChildCount(); i < c; i++) { 1999 // TODO: start delay can be staggered 2000 View v = getChildAt(i); 2001 ((LayoutParams) v.getLayoutParams()).startAnimate(v, 2002 getChildLayoutAnimationDuration(), 0, getChildLayoutAnimationInterpolator()); 2003 } 2004 } 2005 2006 public boolean isChildLayoutAnimated() { 2007 return mAnimateChildLayout; 2008 } 2009 2010 public void setPruneChild(boolean pruneChild) { 2011 if (mPruneChild != pruneChild) { 2012 mPruneChild = pruneChild; 2013 if (mPruneChild) { 2014 removeInvisibleViewsAtEnd(); 2015 removeInvisibleViewsAtFront(); 2016 } 2017 } 2018 } 2019 2020 public boolean getPruneChild() { 2021 return mPruneChild; 2022 } 2023 2024 public void setChildLayoutAnimationInterpolator(Interpolator interpolator) { 2025 mAnimateLayoutChildInterpolator = interpolator; 2026 } 2027 2028 public Interpolator getChildLayoutAnimationInterpolator() { 2029 return mAnimateLayoutChildInterpolator; 2030 } 2031 2032 public void setChildLayoutAnimationDuration(long duration) { 2033 mAnimateLayoutChildDuration = duration; 2034 } 2035 2036 public long getChildLayoutAnimationDuration() { 2037 return mAnimateLayoutChildDuration; 2038 } 2039 2040 private int findImmediateChildIndex(View view) { 2041 while (view != null && view != mBaseGridView) { 2042 int index = mBaseGridView.indexOfChild(view); 2043 if (index >= 0) { 2044 return index; 2045 } 2046 view = (View) view.getParent(); 2047 } 2048 return NO_POSITION; 2049 } 2050 2051 void setFocusSearchDisabled(boolean disabled) { 2052 mFocusSearchDisabled = disabled; 2053 } 2054 2055 boolean isFocusSearchDisabled() { 2056 return mFocusSearchDisabled; 2057 } 2058 2059 @Override 2060 public View onInterceptFocusSearch(View focused, int direction) { 2061 if (mFocusSearchDisabled) { 2062 return focused; 2063 } 2064 return null; 2065 } 2066 2067 boolean hasNextViewInSameRow(int pos) { 2068 if (mGrid == null || pos == NO_POSITION) { 2069 return false; 2070 } 2071 final int focusedRow = mGrid.getLocation(pos).row; 2072 for (int i = 0, count = getChildCount(); i < count; i++) { 2073 int position = getPositionByIndex(i); 2074 StaggeredGrid.Location loc = mGrid.getLocation(position); 2075 if (loc != null && loc.row == focusedRow) { 2076 if (position > pos) { 2077 return true; 2078 } 2079 } 2080 } 2081 return false; 2082 } 2083 2084 boolean hasPreviousViewInSameRow(int pos) { 2085 if (mGrid == null || pos == NO_POSITION) { 2086 return false; 2087 } 2088 final int focusedRow = mGrid.getLocation(pos).row; 2089 for (int i = getChildCount() - 1; i >= 0; i--) { 2090 int position = getPositionByIndex(i); 2091 StaggeredGrid.Location loc = mGrid.getLocation(position); 2092 if (loc != null && loc.row == focusedRow) { 2093 if (position < pos) { 2094 return true; 2095 } 2096 } 2097 } 2098 return false; 2099 } 2100 2101 @Override 2102 public boolean onAddFocusables(RecyclerView recyclerView, 2103 ArrayList<View> views, int direction, int focusableMode) { 2104 if (mFocusSearchDisabled) { 2105 return true; 2106 } 2107 // If this viewgroup or one of its children currently has focus then we 2108 // consider our children for focus searching in main direction on the same row. 2109 // If this viewgroup has no focus and using focus align, we want the system 2110 // to ignore our children and pass focus to the viewgroup, which will pass 2111 // focus on to its children appropriately. 2112 // If this viewgroup has no focus and not using focus align, we want to 2113 // consider the child that does not overlap with padding area. 2114 if (recyclerView.hasFocus()) { 2115 final int movement = getMovement(direction); 2116 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2117 // Move on secondary direction uses default addFocusables(). 2118 return false; 2119 } 2120 final View focused = recyclerView.findFocus(); 2121 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2122 // Add focusables of focused item. 2123 if (focusedPos != NO_POSITION) { 2124 getViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2125 } 2126 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2127 mGrid.getLocation(focusedPos).row : NO_POSITION; 2128 // Add focusables of next neighbor of same row on the focus search direction. 2129 if (mGrid != null) { 2130 final int focusableCount = views.size(); 2131 for (int i = 0, count = getChildCount(); i < count; i++) { 2132 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2133 final View child = getChildAt(index); 2134 if (child.getVisibility() != View.VISIBLE) { 2135 continue; 2136 } 2137 int position = getPositionByIndex(index); 2138 StaggeredGrid.Location loc = mGrid.getLocation(position); 2139 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2140 if (focusedPos == NO_POSITION || 2141 (movement == NEXT_ITEM && position > focusedPos) 2142 || (movement == PREV_ITEM && position < focusedPos)) { 2143 child.addFocusables(views, direction, focusableMode); 2144 if (views.size() > focusableCount) { 2145 break; 2146 } 2147 } 2148 } 2149 } 2150 } 2151 } else { 2152 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2153 // adding views not overlapping padding area to avoid scrolling in gaining focus 2154 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2155 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2156 int focusableCount = views.size(); 2157 for (int i = 0, count = getChildCount(); i < count; i++) { 2158 View child = getChildAt(i); 2159 if (child.getVisibility() == View.VISIBLE) { 2160 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2161 child.addFocusables(views, direction, focusableMode); 2162 } 2163 } 2164 } 2165 // if we cannot find any, then just add all children. 2166 if (views.size() == focusableCount) { 2167 for (int i = 0, count = getChildCount(); i < count; i++) { 2168 View child = getChildAt(i); 2169 if (child.getVisibility() == View.VISIBLE) { 2170 child.addFocusables(views, direction, focusableMode); 2171 } 2172 } 2173 if (views.size() != focusableCount) { 2174 return true; 2175 } 2176 } else { 2177 return true; 2178 } 2179 // if still cannot find any, fall through and add itself 2180 } 2181 if (recyclerView.isFocusable()) { 2182 views.add(recyclerView); 2183 } 2184 } 2185 return true; 2186 } 2187 2188 @Override 2189 public View onFocusSearchFailed(View focused, int direction, Adapter adapter, 2190 Recycler recycler) { 2191 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2192 2193 View view = null; 2194 int movement = getMovement(direction); 2195 final FocusFinder ff = FocusFinder.getInstance(); 2196 if (movement == NEXT_ITEM) { 2197 while (view == null && !appendOneVisibleItem()) { 2198 view = ff.findNextFocus(mBaseGridView, focused, direction); 2199 } 2200 } else if (movement == PREV_ITEM){ 2201 while (view == null && !prependOneVisibleItem()) { 2202 view = ff.findNextFocus(mBaseGridView, focused, direction); 2203 } 2204 } 2205 if (view == null) { 2206 // returning the same view to prevent focus lost when scrolling past the end of the list 2207 if (movement == PREV_ITEM) { 2208 view = mFocusOutFront ? null : focused; 2209 } else if (movement == NEXT_ITEM){ 2210 view = mFocusOutEnd ? null : focused; 2211 } 2212 } 2213 if (DEBUG) Log.v(getTag(), "returning view " + view); 2214 return view; 2215 } 2216 2217 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2218 Rect previouslyFocusedRect) { 2219 switch (mFocusScrollStrategy) { 2220 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2221 default: 2222 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2223 direction, previouslyFocusedRect); 2224 case BaseGridView.FOCUS_SCROLL_PAGE: 2225 case BaseGridView.FOCUS_SCROLL_ITEM: 2226 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2227 direction, previouslyFocusedRect); 2228 } 2229 } 2230 2231 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2232 int direction, Rect previouslyFocusedRect) { 2233 View view = getViewByPosition(mFocusPosition); 2234 if (view != null) { 2235 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2236 if (!result && DEBUG) { 2237 Log.w(getTag(), "failed to request focus on " + view); 2238 } 2239 return result; 2240 } 2241 return false; 2242 } 2243 2244 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2245 int direction, Rect previouslyFocusedRect) { 2246 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2247 int index; 2248 int increment; 2249 int end; 2250 int count = getChildCount(); 2251 if ((direction & View.FOCUS_FORWARD) != 0) { 2252 index = 0; 2253 increment = 1; 2254 end = count; 2255 } else { 2256 index = count - 1; 2257 increment = -1; 2258 end = -1; 2259 } 2260 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2261 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2262 for (int i = index; i != end; i += increment) { 2263 View child = getChildAt(i); 2264 if (child.getVisibility() == View.VISIBLE) { 2265 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2266 if (child.requestFocus(direction, previouslyFocusedRect)) { 2267 return true; 2268 } 2269 } 2270 } 2271 } 2272 return false; 2273 } 2274 2275 private final static int PREV_ITEM = 0; 2276 private final static int NEXT_ITEM = 1; 2277 private final static int PREV_ROW = 2; 2278 private final static int NEXT_ROW = 3; 2279 2280 private int getMovement(int direction) { 2281 int movement = View.FOCUS_LEFT; 2282 2283 if (mOrientation == HORIZONTAL) { 2284 switch(direction) { 2285 case View.FOCUS_LEFT: 2286 movement = PREV_ITEM; 2287 break; 2288 case View.FOCUS_RIGHT: 2289 movement = NEXT_ITEM; 2290 break; 2291 case View.FOCUS_UP: 2292 movement = PREV_ROW; 2293 break; 2294 case View.FOCUS_DOWN: 2295 movement = NEXT_ROW; 2296 break; 2297 } 2298 } else if (mOrientation == VERTICAL) { 2299 switch(direction) { 2300 case View.FOCUS_LEFT: 2301 movement = PREV_ROW; 2302 break; 2303 case View.FOCUS_RIGHT: 2304 movement = NEXT_ROW; 2305 break; 2306 case View.FOCUS_UP: 2307 movement = PREV_ITEM; 2308 break; 2309 case View.FOCUS_DOWN: 2310 movement = NEXT_ITEM; 2311 break; 2312 } 2313 } 2314 2315 return movement; 2316 } 2317 2318 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2319 int focusIndex = getIndexByPosition(mFocusPosition); 2320 if (focusIndex == NO_POSITION) { 2321 return i; 2322 } 2323 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2324 // drawing order is 0 1 2 3 9 8 7 6 5 4 2325 if (i < focusIndex) { 2326 return i; 2327 } else if (i < childCount - 1) { 2328 return focusIndex + childCount - 1 - i; 2329 } else { 2330 return focusIndex; 2331 } 2332 } 2333 2334 @Override 2335 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2336 RecyclerView.Adapter newAdapter) { 2337 discardLayoutInfo(); 2338 super.onAdapterChanged(oldAdapter, newAdapter); 2339 } 2340 2341 private void discardLayoutInfo() { 2342 mGrid = null; 2343 mRows = null; 2344 mRowSizeSecondary = null; 2345 mFirstVisiblePos = -1; 2346 mLastVisiblePos = -1; 2347 mRowSecondarySizeRefresh = false; 2348 } 2349 2350 public void setLayoutEnabled(boolean layoutEnabled) { 2351 if (mLayoutEnabled != layoutEnabled) { 2352 mLayoutEnabled = layoutEnabled; 2353 requestLayout(); 2354 } 2355 } 2356} 2357