GridLayoutManager.java revision 2f97594742886d045ca1ce409ebc6e6e780452f6
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 mFirstAttached; 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() { 111 endAnimate(); 112 mFirstAttached = true; 113 } 114 115 void onViewDetached() { 116 endAnimate(); 117 } 118 119 int getAlignX() { 120 return mAlignX; 121 } 122 123 int getAlignY() { 124 return mAlignY; 125 } 126 127 int getOpticalLeft(View view) { 128 return view.getLeft() + mLeftInset; 129 } 130 131 int getOpticalTop(View view) { 132 return view.getTop() + mTopInset; 133 } 134 135 int getOpticalRight(View view) { 136 return view.getRight() - mRighInset; 137 } 138 139 int getOpticalBottom(View view) { 140 return view.getBottom() - mBottomInset; 141 } 142 143 int getOpticalWidth(View view) { 144 return view.getWidth() - mLeftInset - mRighInset; 145 } 146 147 int getOpticalHeight(View view) { 148 return view.getHeight() - mTopInset - mBottomInset; 149 } 150 151 void setAlignX(int alignX) { 152 mAlignX = alignX; 153 } 154 155 void setAlignY(int alignY) { 156 mAlignY = alignY; 157 } 158 159 void setOpticalInsets(int leftInset, int topInset, int rightInset, int bottomInset) { 160 mLeftInset = leftInset; 161 mTopInset = topInset; 162 mRighInset = rightInset; 163 mBottomInset = bottomInset; 164 } 165 166 private TimeAnimator.TimeListener mTimeListener = new TimeAnimator.TimeListener() { 167 @Override 168 public void onTimeUpdate(TimeAnimator animation, long totalTime, long deltaTime) { 169 if (mView == null) { 170 return; 171 } 172 if (totalTime >= mDuration) { 173 endAnimate(); 174 } else { 175 float fraction = (float) (totalTime / (double)mDuration); 176 float fractionToEnd = 1 - mAnimator 177 .getInterpolator().getInterpolation(fraction); 178 if (mOrientation == HORIZONTAL) { 179 if (mLayoutForward) { 180 mView.setTranslationX(fractionToEnd * mAnimationStartTranslationX); 181 } else { 182 mView.setTranslationX(fractionToEnd * mAnimationStartTranslationX - 183 fractionToEnd * (mView.getMeasuredWidth() - mSize)); 184 } 185 } else { 186 if (mLayoutForward) { 187 mView.setTranslationY(fractionToEnd * mAnimationStartTranslationY); 188 } else { 189 mView.setTranslationY(fractionToEnd * mAnimationStartTranslationY - 190 fractionToEnd * (mView.getMeasuredHeight() - mSize)); 191 } 192 } 193 invalidateItemDecoration(); 194 } 195 } 196 }; 197 198 void startAnimate(GridLayoutManager layout, View view, long startDelay) { 199 if (mAnimator == null) { 200 mAnimator = new TimeAnimator(); 201 mAnimator.setTimeListener(mTimeListener); 202 } 203 if (mFirstAttached) { 204 // first time record the initial location and return without animation 205 // TODO do we need initial animation? 206 mViewX = layout.getScrollOffsetX() + getOpticalLeft(view); 207 mViewY = layout.getScrollOffsetY() + getOpticalTop(view); 208 mOrientation = layout.mOrientation; 209 mSize = mOrientation == HORIZONTAL ? view.getMeasuredWidth() : view.getMeasuredHeight(); 210 mFirstAttached = false; 211 return; 212 } 213 mView = view; 214 int newViewX = layout.getScrollOffsetX() + getOpticalLeft(mView); 215 int newViewY = layout.getScrollOffsetY() + getOpticalTop(mView); 216 if (newViewX != mViewX || newViewY != mViewY) { 217 mAnimator.cancel(); 218 mAnimationStartTranslationX = mView.getTranslationX(); 219 mAnimationStartTranslationY = mView.getTranslationY(); 220 mAnimationStartTranslationX += mViewX - newViewX; 221 mAnimationStartTranslationY += mViewY - newViewY; 222 mDuration = layout.getChildLayoutAnimationDuration(); 223 mAnimator.setDuration(mDuration); 224 mAnimator.setInterpolator(layout.getChildLayoutAnimationInterpolator()); 225 mAnimator.setStartDelay(startDelay); 226 mAnimator.start(); 227 mViewX = newViewX; 228 mViewY = newViewY; 229 } 230 } 231 232 void endAnimate() { 233 if (mAnimator != null) { 234 mAnimator.end(); 235 } 236 if (mView != null) { 237 mSize = mOrientation == HORIZONTAL ? 238 mView.getMeasuredWidth() : mView.getMeasuredHeight(); 239 mView.setTranslationX(0); 240 mView.setTranslationY(0); 241 mView = null; 242 } 243 } 244 245 private void invalidateItemDecoration() { 246 ViewParent parent = mView.getParent(); 247 if (parent instanceof RecyclerView) { 248 // TODO: we only need invalidate parent if it has ItemDecoration 249 ((RecyclerView) parent).invalidate(); 250 } 251 } 252 } 253 254 private static final String TAG = "GridLayoutManager"; 255 private static final boolean DEBUG = false; 256 257 private static final Interpolator sDefaultAnimationChildLayoutInterpolator 258 = new DecelerateInterpolator(); 259 260 private static final long DEFAULT_CHILD_ANIMATION_DURATION_MS = 250; 261 262 private String getTag() { 263 return TAG + ":" + mBaseGridView.getId(); 264 } 265 266 private final BaseGridView mBaseGridView; 267 268 /** 269 * The orientation of a "row". 270 */ 271 private int mOrientation = HORIZONTAL; 272 273 private RecyclerView.Adapter mAdapter; 274 private RecyclerView.Recycler mRecycler; 275 276 private boolean mInLayout = false; 277 278 private OnChildSelectedListener mChildSelectedListener = null; 279 280 /** 281 * The focused position, it's not the currently visually aligned position 282 * but it is the final position that we intend to focus on. If there are 283 * multiple setSelection() called, mFocusPosition saves last value. 284 */ 285 private int mFocusPosition = NO_POSITION; 286 287 /** 288 * Force a full layout under certain situations. 289 */ 290 private boolean mForceFullLayout; 291 292 /** 293 * True if layout is enabled. 294 */ 295 private boolean mLayoutEnabled = true; 296 297 /** 298 * The scroll offsets of the viewport relative to the entire view. 299 */ 300 private int mScrollOffsetPrimary; 301 private int mScrollOffsetSecondary; 302 303 /** 304 * User-specified row height/column width. Can be WRAP_CONTENT. 305 */ 306 private int mRowSizeSecondaryRequested; 307 308 /** 309 * The fixed size of each grid item in the secondary direction. This corresponds to 310 * the row height, equal for all rows. Grid items may have variable length 311 * in the primary direction. 312 */ 313 private int mFixedRowSizeSecondary; 314 315 /** 316 * Tracks the secondary size of each row. 317 */ 318 private int[] mRowSizeSecondary; 319 320 /** 321 * Flag controlling whether the current/next layout should 322 * be updating the secondary size of rows. 323 */ 324 private boolean mRowSecondarySizeRefresh; 325 326 /** 327 * The maximum measured size of the view. 328 */ 329 private int mMaxSizeSecondary; 330 331 /** 332 * Margin between items. 333 */ 334 private int mHorizontalMargin; 335 /** 336 * Margin between items vertically. 337 */ 338 private int mVerticalMargin; 339 /** 340 * Margin in main direction. 341 */ 342 private int mMarginPrimary; 343 /** 344 * Margin in second direction. 345 */ 346 private int mMarginSecondary; 347 /** 348 * How to position child in secondary direction. 349 */ 350 private int mGravity = Gravity.LEFT | Gravity.TOP; 351 /** 352 * The number of rows in the grid. 353 */ 354 private int mNumRows; 355 /** 356 * Number of rows requested, can be 0 to be determined by parent size and 357 * rowHeight. 358 */ 359 private int mNumRowsRequested = 1; 360 361 /** 362 * Tracking start/end position of each row for visible items. 363 */ 364 private StaggeredGrid.Row[] mRows; 365 366 /** 367 * Saves grid information of each view. 368 */ 369 private StaggeredGrid mGrid; 370 /** 371 * Position of first item (included) that has attached views. 372 */ 373 private int mFirstVisiblePos; 374 /** 375 * Position of last item (included) that has attached views. 376 */ 377 private int mLastVisiblePos; 378 379 /** 380 * Focus Scroll strategy. 381 */ 382 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 383 /** 384 * Defines how item view is aligned in the window. 385 */ 386 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 387 388 /** 389 * Defines how item view is aligned. 390 */ 391 private final ItemAlignment mItemAlignment = new ItemAlignment(); 392 393 /** 394 * Dimensions of the view, width or height depending on orientation. 395 */ 396 private int mSizePrimary; 397 398 /** 399 * Allow DPAD key to navigate out at the front of the View (where position = 0), 400 * default is false. 401 */ 402 private boolean mFocusOutFront; 403 404 /** 405 * Allow DPAD key to navigate out at the end of the view, default is false. 406 */ 407 private boolean mFocusOutEnd; 408 409 /** 410 * True if focus search is disabled. 411 */ 412 private boolean mFocusSearchDisabled; 413 414 /** 415 * Animate layout changes from a child resizing or adding/removing a child. 416 */ 417 private boolean mAnimateChildLayout = true; 418 419 /** 420 * Interpolator used to animate layout of children. 421 */ 422 private Interpolator mAnimateLayoutChildInterpolator = sDefaultAnimationChildLayoutInterpolator; 423 424 /** 425 * Duration used to animate layout of children. 426 */ 427 private long mAnimateLayoutChildDuration = DEFAULT_CHILD_ANIMATION_DURATION_MS; 428 429 public GridLayoutManager(BaseGridView baseGridView) { 430 mBaseGridView = baseGridView; 431 } 432 433 public void setOrientation(int orientation) { 434 if (orientation != HORIZONTAL && orientation != VERTICAL) { 435 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 436 return; 437 } 438 439 mOrientation = orientation; 440 mWindowAlignment.setOrientation(orientation); 441 mItemAlignment.setOrientation(orientation); 442 mForceFullLayout = true; 443 } 444 445 public int getFocusScrollStrategy() { 446 return mFocusScrollStrategy; 447 } 448 449 public void setFocusScrollStrategy(int focusScrollStrategy) { 450 mFocusScrollStrategy = focusScrollStrategy; 451 } 452 453 public void setWindowAlignment(int windowAlignment) { 454 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 455 } 456 457 public int getWindowAlignment() { 458 return mWindowAlignment.mainAxis().getWindowAlignment(); 459 } 460 461 public void setWindowAlignmentOffset(int alignmentOffset) { 462 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 463 } 464 465 public int getWindowAlignmentOffset() { 466 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 467 } 468 469 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 470 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 471 } 472 473 public float getWindowAlignmentOffsetPercent() { 474 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 475 } 476 477 public void setItemAlignmentOffset(int alignmentOffset) { 478 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 479 updateChildAlignments(); 480 } 481 482 public int getItemAlignmentOffset() { 483 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 484 } 485 486 public void setItemAlignmentOffsetPercent(float offsetPercent) { 487 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 488 updateChildAlignments(); 489 } 490 491 public float getItemAlignmentOffsetPercent() { 492 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 493 } 494 495 public void setItemAlignmentViewId(int viewId) { 496 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 497 updateChildAlignments(); 498 } 499 500 public int getItemAlignmentViewId() { 501 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 502 } 503 504 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 505 mFocusOutFront = throughFront; 506 mFocusOutEnd = throughEnd; 507 } 508 509 public void setNumRows(int numRows) { 510 if (numRows < 0) throw new IllegalArgumentException(); 511 mNumRowsRequested = numRows; 512 mForceFullLayout = true; 513 } 514 515 /** 516 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 517 */ 518 public void setRowHeight(int height) { 519 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 520 mRowSizeSecondaryRequested = height; 521 } else { 522 throw new IllegalArgumentException("Invalid row height: " + height); 523 } 524 } 525 526 public void setItemMargin(int margin) { 527 mVerticalMargin = mHorizontalMargin = margin; 528 mMarginPrimary = mMarginSecondary = margin; 529 } 530 531 public void setVerticalMargin(int margin) { 532 if (mOrientation == HORIZONTAL) { 533 mMarginSecondary = mVerticalMargin = margin; 534 } else { 535 mMarginPrimary = mVerticalMargin = margin; 536 } 537 } 538 539 public void setHorizontalMargin(int margin) { 540 if (mOrientation == HORIZONTAL) { 541 mMarginPrimary = mHorizontalMargin = margin; 542 } else { 543 mMarginSecondary = mHorizontalMargin = margin; 544 } 545 } 546 547 public int getVerticalMargin() { 548 return mVerticalMargin; 549 } 550 551 public int getHorizontalMargin() { 552 return mHorizontalMargin; 553 } 554 555 public void setGravity(int gravity) { 556 mGravity = gravity; 557 } 558 559 protected boolean hasDoneFirstLayout() { 560 return mGrid != null; 561 } 562 563 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 564 mChildSelectedListener = listener; 565 } 566 567 private int getPositionByView(View view) { 568 return getPositionByIndex(mBaseGridView.indexOfChild(view)); 569 } 570 571 private int getPositionByIndex(int index) { 572 if (index < 0) { 573 return NO_POSITION; 574 } 575 return mFirstVisiblePos + index; 576 } 577 578 private View getViewByPosition(int position) { 579 int index = getIndexByPosition(position); 580 if (index < 0) { 581 return null; 582 } 583 return getChildAt(index); 584 } 585 586 private int getIndexByPosition(int position) { 587 if (mFirstVisiblePos < 0 || 588 position < mFirstVisiblePos || position > mLastVisiblePos) { 589 return NO_POSITION; 590 } 591 return position - mFirstVisiblePos; 592 } 593 594 private void dispatchChildSelected() { 595 if (mChildSelectedListener == null) { 596 return; 597 } 598 599 View view = getViewByPosition(mFocusPosition); 600 601 if (mFocusPosition != NO_POSITION) { 602 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 603 mAdapter.getItemId(mFocusPosition)); 604 } else { 605 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 606 } 607 } 608 609 @Override 610 public boolean canScrollHorizontally() { 611 // We can scroll horizontally if we have horizontal orientation, or if 612 // we are vertical and have more than one column. 613 return mOrientation == HORIZONTAL || mNumRows > 1; 614 } 615 616 @Override 617 public boolean canScrollVertically() { 618 // We can scroll vertically if we have vertical orientation, or if we 619 // are horizontal and have more than one row. 620 return mOrientation == VERTICAL || mNumRows > 1; 621 } 622 623 @Override 624 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 625 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 626 ViewGroup.LayoutParams.WRAP_CONTENT); 627 } 628 629 @Override 630 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 631 return new LayoutParams(context, attrs); 632 } 633 634 @Override 635 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 636 if (lp instanceof LayoutParams) { 637 return new LayoutParams((LayoutParams) lp); 638 } else if (lp instanceof RecyclerView.LayoutParams) { 639 return new LayoutParams((RecyclerView.LayoutParams) lp); 640 } else if (lp instanceof MarginLayoutParams) { 641 return new LayoutParams((MarginLayoutParams) lp); 642 } else { 643 return new LayoutParams(lp); 644 } 645 } 646 647 protected View getViewForPosition(int position) { 648 View v = mRecycler.getViewForPosition(mAdapter, position); 649 if (v != null) { 650 ((LayoutParams) v.getLayoutParams()).onViewAttached(); 651 } 652 return v; 653 } 654 655 final int getOpticalLeft(View v) { 656 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 657 } 658 659 final int getOpticalRight(View v) { 660 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 661 } 662 663 final int getOpticalTop(View v) { 664 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 665 } 666 667 final int getOpticalBottom(View v) { 668 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 669 } 670 671 private int getViewMin(View v) { 672 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 673 } 674 675 private int getViewMax(View v) { 676 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 677 } 678 679 private int getViewCenter(View view) { 680 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 681 } 682 683 private int getViewCenterSecondary(View view) { 684 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 685 } 686 687 private int getViewCenterX(View v) { 688 LayoutParams p = (LayoutParams) v.getLayoutParams(); 689 return p.getOpticalLeft(v) + p.getAlignX(); 690 } 691 692 private int getViewCenterY(View v) { 693 LayoutParams p = (LayoutParams) v.getLayoutParams(); 694 return p.getOpticalTop(v) + p.getAlignY(); 695 } 696 697 private void setViewLayoutForward(View v, boolean layoutForward) { 698 LayoutParams p = (LayoutParams) v.getLayoutParams(); 699 p.mLayoutForward = layoutForward; 700 } 701 702 private boolean getIsViewLayoutForward(View v) { 703 return ((LayoutParams) v.getLayoutParams()).mLayoutForward; 704 } 705 706 /** 707 * Re-initialize data structures for a data change or handling invisible 708 * selection. The method tries its best to preserve position information so 709 * that staggered grid looks same before and after re-initialize. 710 * @param focusPosition The initial focusPosition that we would like to 711 * focus on. 712 * @return Actual position that can be focused on. 713 */ 714 private int init(RecyclerView.Adapter adapter, RecyclerView.Recycler recycler, 715 int focusPosition) { 716 717 final int newItemCount = adapter.getItemCount(); 718 719 if (focusPosition == NO_POSITION && newItemCount > 0) { 720 // if focus position is never set before, initialize it to 0 721 focusPosition = 0; 722 } 723 // If adapter has changed then caches are invalid; otherwise, 724 // we try to maintain each row's position if number of rows keeps the same 725 // and existing mGrid contains the focusPosition. 726 if (mRows != null && mNumRows == mRows.length && 727 mGrid != null && mGrid.getSize() > 0 && focusPosition >= 0 && 728 focusPosition >= mGrid.getFirstIndex() && 729 focusPosition <= mGrid.getLastIndex()) { 730 // strip mGrid to a subset (like a column) that contains focusPosition 731 mGrid.stripDownTo(focusPosition); 732 // make sure that remaining items do not exceed new adapter size 733 int firstIndex = mGrid.getFirstIndex(); 734 int lastIndex = mGrid.getLastIndex(); 735 if (DEBUG) { 736 Log .v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " + lastIndex); 737 } 738 for (int i = lastIndex; i >=firstIndex; i--) { 739 if (i >= newItemCount) { 740 mGrid.removeLast(); 741 } 742 } 743 if (mGrid.getSize() == 0) { 744 focusPosition = newItemCount - 1; 745 // initialize row start locations 746 for (int i = 0; i < mNumRows; i++) { 747 mRows[i].low = 0; 748 mRows[i].high = 0; 749 } 750 if (DEBUG) Log.v(getTag(), "mGrid zero size"); 751 } else { 752 // initialize row start locations 753 for (int i = 0; i < mNumRows; i++) { 754 mRows[i].low = Integer.MAX_VALUE; 755 mRows[i].high = Integer.MIN_VALUE; 756 } 757 firstIndex = mGrid.getFirstIndex(); 758 lastIndex = mGrid.getLastIndex(); 759 if (focusPosition > lastIndex) { 760 focusPosition = mGrid.getLastIndex(); 761 } 762 if (DEBUG) { 763 Log.v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " 764 + lastIndex + " focusPosition " + focusPosition); 765 } 766 // fill rows with minimal view positions of the subset 767 for (int i = firstIndex; i <= lastIndex; i++) { 768 View v = getViewByPosition(i); 769 if (v == null) { 770 continue; 771 } 772 int row = mGrid.getLocation(i).row; 773 int low = getViewMin(v) + mScrollOffsetPrimary; 774 if (low < mRows[row].low) { 775 mRows[row].low = mRows[row].high = low; 776 } 777 } 778 // fill other rows that does not include the subset using first item 779 int firstItemRowPosition = mRows[mGrid.getLocation(firstIndex).row].low; 780 if (firstItemRowPosition == Integer.MAX_VALUE) { 781 firstItemRowPosition = 0; 782 } 783 for (int i = 0; i < mNumRows; i++) { 784 if (mRows[i].low == Integer.MAX_VALUE) { 785 mRows[i].low = mRows[i].high = firstItemRowPosition; 786 } 787 } 788 } 789 790 // Same adapter, we can reuse any attached views 791 detachAndScrapAttachedViews(recycler); 792 793 } else { 794 // otherwise recreate data structure 795 mRows = new StaggeredGrid.Row[mNumRows]; 796 mRowSizeSecondary = new int[mNumRows]; 797 798 for (int i = 0; i < mNumRows; i++) { 799 mRows[i] = new StaggeredGrid.Row(); 800 } 801 mGrid = new StaggeredGridDefault(); 802 if (newItemCount == 0) { 803 focusPosition = NO_POSITION; 804 } else if (focusPosition >= newItemCount) { 805 focusPosition = newItemCount - 1; 806 } 807 808 // Adapter may have changed so remove all attached views permanently 809 removeAllViews(); 810 811 mScrollOffsetPrimary = 0; 812 mScrollOffsetSecondary = 0; 813 mWindowAlignment.reset(); 814 } 815 816 mAdapter = adapter; 817 mRecycler = recycler; 818 mGrid.setProvider(mGridProvider); 819 // mGrid share the same Row array information 820 mGrid.setRows(mRows); 821 mFirstVisiblePos = mLastVisiblePos = NO_POSITION; 822 823 initScrollController(); 824 updateScrollSecondAxis(); 825 826 return focusPosition; 827 } 828 829 private int getRowSizeSecondary(int rowIndex) { 830 if (mFixedRowSizeSecondary != 0) { 831 return mFixedRowSizeSecondary; 832 } 833 if (mRowSizeSecondary == null) { 834 return 0; 835 } 836 return mRowSizeSecondary[rowIndex]; 837 } 838 839 private int getRowStartSecondary(int rowIndex) { 840 int start = 0; 841 for (int i = 0; i < rowIndex; i++) { 842 start += getRowSizeSecondary(i) + mMarginSecondary; 843 } 844 return start; 845 } 846 847 private int getSizeSecondary() { 848 return getRowStartSecondary(mNumRows - 1) + getRowSizeSecondary(mNumRows - 1); 849 } 850 851 private boolean processRowSizeSecondary(boolean measure) { 852 if (mFixedRowSizeSecondary != 0) { 853 return false; 854 } 855 856 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 857 boolean changed = false; 858 859 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 860 int rowSize = 0; 861 862 final int rowItemCount = rows[rowIndex].size(); 863 if (DEBUG) Log.v(getTag(), "processRowSizeSecondary row " + rowIndex + 864 " rowItemCount " + rowItemCount); 865 866 for (int i = 0; i < rowItemCount; i++) { 867 final int position = rows[rowIndex].get(i); 868 final View view = getViewByPosition(position); 869 if (measure && view.isLayoutRequested()) { 870 measureChild(view, rowIndex); 871 } 872 // If this view isn't visible, we ignore it. 873 if (getOpticalRight(view) < 0 || getOpticalLeft(view) > getWidth() || 874 getOpticalBottom(view) < 0 || getOpticalTop(view) > getHeight()) { 875 continue; 876 } 877 final int secondarySize = mOrientation == HORIZONTAL ? 878 view.getMeasuredHeight() : view.getMeasuredWidth(); 879 if (secondarySize > rowSize) { 880 rowSize = secondarySize; 881 } 882 } 883 if (DEBUG) Log.v(getTag(), "row " + rowIndex + " rowItemCount " + rowItemCount + 884 " rowSize " + rowSize); 885 886 if (mRowSizeSecondary[rowIndex] != rowSize) { 887 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 888 ", " + rowSize); 889 890 mRowSizeSecondary[rowIndex] = rowSize; 891 changed = true; 892 } 893 } 894 895 return changed; 896 } 897 898 /** 899 * Checks if we need to update row secondary sizes. 900 */ 901 private void updateRowSecondarySizeRefresh() { 902 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 903 if (mRowSecondarySizeRefresh) { 904 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 905 forceRequestLayout(); 906 } 907 } 908 909 private void forceRequestLayout() { 910 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 911 // RecyclerView prevents us from requesting layout in many cases 912 // (during layout, during scroll, etc.) 913 // For secondary row size wrap_content support we currently need a 914 // second layout pass to update the measured size after having measured 915 // and added child views in layoutChildren. 916 // Force the second layout by posting a delayed runnable. 917 // TODO: investigate allowing a second layout pass, 918 // or move child add/measure logic to the measure phase. 919 mBaseGridView.getHandler().post(new Runnable() { 920 @Override 921 public void run() { 922 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 923 requestLayout(); 924 } 925 }); 926 } 927 928 @Override 929 public void onMeasure(int widthSpec, int heightSpec) { 930 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 931 int measuredSizeSecondary; 932 if (mOrientation == HORIZONTAL) { 933 sizePrimary = MeasureSpec.getSize(widthSpec); 934 sizeSecondary = MeasureSpec.getSize(heightSpec); 935 modeSecondary = MeasureSpec.getMode(heightSpec); 936 paddingSecondary = getPaddingTop() + getPaddingBottom(); 937 } else { 938 sizeSecondary = MeasureSpec.getSize(widthSpec); 939 sizePrimary = MeasureSpec.getSize(heightSpec); 940 modeSecondary = MeasureSpec.getMode(widthSpec); 941 paddingSecondary = getPaddingLeft() + getPaddingRight(); 942 } 943 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 944 " heightSpec " + Integer.toHexString(heightSpec) + 945 " modeSecondary " + Integer.toHexString(modeSecondary) + 946 " sizeSecondary " + sizeSecondary + " " + this); 947 948 mMaxSizeSecondary = sizeSecondary; 949 950 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 951 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 952 mFixedRowSizeSecondary = 0; 953 954 // Measure all current children and update cached row heights 955 if (mGrid != null) { 956 processRowSizeSecondary(true); 957 } 958 959 switch (modeSecondary) { 960 case MeasureSpec.UNSPECIFIED: 961 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 962 break; 963 case MeasureSpec.AT_MOST: 964 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 965 mMaxSizeSecondary); 966 break; 967 case MeasureSpec.EXACTLY: 968 measuredSizeSecondary = mMaxSizeSecondary; 969 break; 970 default: 971 throw new IllegalStateException("wrong spec"); 972 } 973 974 } else { 975 switch (modeSecondary) { 976 case MeasureSpec.UNSPECIFIED: 977 if (mRowSizeSecondaryRequested == 0) { 978 if (mOrientation == HORIZONTAL) { 979 throw new IllegalStateException("Must specify rowHeight or view height"); 980 } else { 981 throw new IllegalStateException("Must specify columnWidth or view width"); 982 } 983 } 984 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 985 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 986 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 987 * (mNumRows - 1) + paddingSecondary; 988 break; 989 case MeasureSpec.AT_MOST: 990 case MeasureSpec.EXACTLY: 991 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 992 mNumRows = 1; 993 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 994 } else if (mNumRowsRequested == 0) { 995 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 996 mNumRows = (sizeSecondary + mMarginSecondary) 997 / (mRowSizeSecondaryRequested + mMarginSecondary); 998 } else if (mRowSizeSecondaryRequested == 0) { 999 mNumRows = mNumRowsRequested; 1000 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 1001 * (mNumRows - 1)) / mNumRows; 1002 } else { 1003 mNumRows = mNumRowsRequested; 1004 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1005 } 1006 measuredSizeSecondary = sizeSecondary; 1007 if (modeSecondary == MeasureSpec.AT_MOST) { 1008 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1009 * (mNumRows - 1) + paddingSecondary; 1010 if (childrenSize < measuredSizeSecondary) { 1011 measuredSizeSecondary = childrenSize; 1012 } 1013 } 1014 break; 1015 default: 1016 throw new IllegalStateException("wrong spec"); 1017 } 1018 } 1019 if (mOrientation == HORIZONTAL) { 1020 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1021 } else { 1022 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1023 } 1024 if (DEBUG) { 1025 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1026 " measuredSizeSecondary " + measuredSizeSecondary + 1027 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1028 " mNumRows " + mNumRows); 1029 } 1030 } 1031 1032 private void measureChild(View child, int rowIndex) { 1033 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1034 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1035 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1036 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1037 int widthSpec, heightSpec; 1038 1039 if (mOrientation == HORIZONTAL) { 1040 widthSpec = ViewGroup.getChildMeasureSpec( 1041 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1042 0, lp.width); 1043 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1044 } else { 1045 heightSpec = ViewGroup.getChildMeasureSpec( 1046 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1047 0, lp.height); 1048 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1049 } 1050 1051 child.measure(widthSpec, heightSpec); 1052 1053 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1054 " widthSpec " + Integer.toHexString(widthSpec) + 1055 " heightSpec " + Integer.toHexString(heightSpec) + 1056 " measuredWidth " + child.getMeasuredWidth() + 1057 " measuredHeight " + child.getMeasuredHeight()); 1058 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1059 } 1060 1061 private StaggeredGrid.Provider mGridProvider = new StaggeredGrid.Provider() { 1062 1063 @Override 1064 public int getCount() { 1065 return mAdapter.getItemCount(); 1066 } 1067 1068 @Override 1069 public void createItem(int index, int rowIndex, boolean append) { 1070 View v = getViewForPosition(index); 1071 if (mFirstVisiblePos >= 0) { 1072 // when StaggeredGrid append or prepend item, we must guarantee 1073 // that sibling item has created views already. 1074 if (append && index != mLastVisiblePos + 1) { 1075 throw new RuntimeException(); 1076 } else if (!append && index != mFirstVisiblePos - 1) { 1077 throw new RuntimeException(); 1078 } 1079 } 1080 1081 if (append) { 1082 addView(v); 1083 } else { 1084 addView(v, 0); 1085 } 1086 1087 measureChild(v, rowIndex); 1088 1089 int length = mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1090 int start, end; 1091 if (append) { 1092 start = mRows[rowIndex].high; 1093 if (start != mRows[rowIndex].low) { 1094 // if there are existing item in the row, add margin between 1095 start += mMarginPrimary; 1096 } else { 1097 final int lastRow = mRows.length - 1; 1098 if (lastRow != rowIndex && mRows[lastRow].high != mRows[lastRow].low) { 1099 // if there are existing item in the last row, insert 1100 // the new item after the last item of last row. 1101 start = mRows[lastRow].high + mMarginPrimary; 1102 } 1103 } 1104 end = start + length; 1105 mRows[rowIndex].high = end; 1106 } else { 1107 end = mRows[rowIndex].low; 1108 if (end != mRows[rowIndex].high) { 1109 end -= mMarginPrimary; 1110 } else if (0 != rowIndex && mRows[0].high != mRows[0].low) { 1111 // if there are existing item in the first row, insert 1112 // the new item before the first item of first row. 1113 end = mRows[0].low - mMarginPrimary; 1114 } 1115 start = end - length; 1116 mRows[rowIndex].low = start; 1117 } 1118 if (mFirstVisiblePos < 0) { 1119 mFirstVisiblePos = mLastVisiblePos = index; 1120 } else { 1121 if (append) { 1122 mLastVisiblePos++; 1123 } else { 1124 mFirstVisiblePos--; 1125 } 1126 } 1127 if (DEBUG) Log.v(getTag(), "start " + start + " end " + end); 1128 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1129 layoutChild(rowIndex, v, start - mScrollOffsetPrimary, end - mScrollOffsetPrimary, 1130 startSecondary); 1131 if (DEBUG) { 1132 Log.d(getTag(), "addView " + index + " " + v); 1133 } 1134 updateScrollMin(); 1135 updateScrollMax(); 1136 1137 setViewLayoutForward(v, append); 1138 } 1139 }; 1140 1141 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1142 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1143 : v.getMeasuredWidth(); 1144 if (mFixedRowSizeSecondary > 0) { 1145 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1146 } 1147 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1148 final int horizontalGravity = mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1149 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1150 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1151 // do nothing 1152 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1153 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1154 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1155 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1156 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1157 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1158 } 1159 int left, top, right, bottom; 1160 if (mOrientation == HORIZONTAL) { 1161 left = start; 1162 top = startSecondary; 1163 right = end; 1164 bottom = startSecondary + sizeSecondary; 1165 } else { 1166 top = start; 1167 left = startSecondary; 1168 bottom = end; 1169 right = startSecondary + sizeSecondary; 1170 } 1171 v.layout(left, top, right, bottom); 1172 updateChildOpticalInsets(v, left, top, right, bottom); 1173 updateChildAlignments(v); 1174 } 1175 1176 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1177 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1178 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1179 v.getRight() - right, v.getBottom() - bottom); 1180 } 1181 1182 private void updateChildAlignments(View v) { 1183 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1184 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1185 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1186 } 1187 1188 private void updateChildAlignments() { 1189 for (int i = 0, c = getChildCount(); i < c; i++) { 1190 updateChildAlignments(getChildAt(i)); 1191 } 1192 } 1193 1194 private boolean needsAppendVisibleItem() { 1195 if (mLastVisiblePos < mFocusPosition) { 1196 return true; 1197 } 1198 int right = mScrollOffsetPrimary + mSizePrimary; 1199 for (int i = 0; i < mNumRows; i++) { 1200 if (mRows[i].low == mRows[i].high) { 1201 if (mRows[i].high < right) { 1202 return true; 1203 } 1204 } else if (mRows[i].high < right - mMarginPrimary) { 1205 return true; 1206 } 1207 } 1208 return false; 1209 } 1210 1211 private boolean needsPrependVisibleItem() { 1212 if (mFirstVisiblePos > mFocusPosition) { 1213 return true; 1214 } 1215 for (int i = 0; i < mNumRows; i++) { 1216 if (mRows[i].low == mRows[i].high) { 1217 if (mRows[i].low > mScrollOffsetPrimary) { 1218 return true; 1219 } 1220 } else if (mRows[i].low - mMarginPrimary > mScrollOffsetPrimary) { 1221 return true; 1222 } 1223 } 1224 return false; 1225 } 1226 1227 // Append one column if possible and return true if reach end. 1228 private boolean appendOneVisibleItem() { 1229 while (true) { 1230 if (mLastVisiblePos != NO_POSITION && mLastVisiblePos < mAdapter.getItemCount() -1 && 1231 mLastVisiblePos < mGrid.getLastIndex()) { 1232 // append invisible view of saved location till last row 1233 final int index = mLastVisiblePos + 1; 1234 final int row = mGrid.getLocation(index).row; 1235 mGridProvider.createItem(index, row, true); 1236 if (row == mNumRows - 1) { 1237 return false; 1238 } 1239 } else if ((mLastVisiblePos == NO_POSITION && mAdapter.getItemCount() > 0) || 1240 (mLastVisiblePos != NO_POSITION && 1241 mLastVisiblePos < mAdapter.getItemCount() - 1)) { 1242 mGrid.appendItems(mScrollOffsetPrimary + mSizePrimary); 1243 return false; 1244 } else { 1245 return true; 1246 } 1247 } 1248 } 1249 1250 private void appendVisibleItems() { 1251 while (needsAppendVisibleItem()) { 1252 if (appendOneVisibleItem()) { 1253 break; 1254 } 1255 } 1256 } 1257 1258 // Prepend one column if possible and return true if reach end. 1259 private boolean prependOneVisibleItem() { 1260 while (true) { 1261 if (mFirstVisiblePos > 0) { 1262 if (mFirstVisiblePos > mGrid.getFirstIndex()) { 1263 // prepend invisible view of saved location till first row 1264 final int index = mFirstVisiblePos - 1; 1265 final int row = mGrid.getLocation(index).row; 1266 mGridProvider.createItem(index, row, false); 1267 if (row == 0) { 1268 return false; 1269 } 1270 } else { 1271 mGrid.prependItems(mScrollOffsetPrimary); 1272 return false; 1273 } 1274 } else { 1275 return true; 1276 } 1277 } 1278 } 1279 1280 private void prependVisibleItems() { 1281 while (needsPrependVisibleItem()) { 1282 if (prependOneVisibleItem()) { 1283 break; 1284 } 1285 } 1286 } 1287 1288 private void removeChildAt(int position) { 1289 View v = getViewByPosition(position); 1290 if (v != null) { 1291 if (DEBUG) { 1292 Log.d(getTag(), "removeAndRecycleViewAt " + position); 1293 } 1294 ((LayoutParams) v.getLayoutParams()).onViewDetached(); 1295 removeAndRecycleViewAt(getIndexByPosition(position), mRecycler); 1296 } 1297 } 1298 1299 private void removeInvisibleViewsAtEnd() { 1300 boolean update = false; 1301 while(mLastVisiblePos > mFirstVisiblePos && mLastVisiblePos > mFocusPosition) { 1302 View view = getViewByPosition(mLastVisiblePos); 1303 if (getViewMin(view) > mSizePrimary) { 1304 removeChildAt(mLastVisiblePos); 1305 mLastVisiblePos--; 1306 update = true; 1307 } else { 1308 break; 1309 } 1310 } 1311 if (update) { 1312 updateRowsMinMax(); 1313 } 1314 } 1315 1316 private void removeInvisibleViewsAtFront() { 1317 boolean update = false; 1318 while(mLastVisiblePos > mFirstVisiblePos && mFirstVisiblePos < mFocusPosition) { 1319 View view = getViewByPosition(mFirstVisiblePos); 1320 if (getViewMax(view) < 0) { 1321 removeChildAt(mFirstVisiblePos); 1322 mFirstVisiblePos++; 1323 update = true; 1324 } else { 1325 break; 1326 } 1327 } 1328 if (update) { 1329 updateRowsMinMax(); 1330 } 1331 } 1332 1333 private void updateRowsMinMax() { 1334 if (mFirstVisiblePos < 0) { 1335 return; 1336 } 1337 for (int i = 0; i < mNumRows; i++) { 1338 mRows[i].low = Integer.MAX_VALUE; 1339 mRows[i].high = Integer.MIN_VALUE; 1340 } 1341 for (int i = mFirstVisiblePos; i <= mLastVisiblePos; i++) { 1342 View view = getViewByPosition(i); 1343 int row = mGrid.getLocation(i).row; 1344 int low = getViewMin(view) + mScrollOffsetPrimary; 1345 if (low < mRows[row].low) { 1346 mRows[row].low = low; 1347 } 1348 int high = getViewMax(view) + mScrollOffsetPrimary; 1349 if (high > mRows[row].high) { 1350 mRows[row].high = high; 1351 } 1352 } 1353 } 1354 1355 // Fast layout when there is no structure change, adapter change, etc. 1356 protected void fastRelayout() { 1357 initScrollController(); 1358 1359 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 1360 1361 // relayout and repositioning views on each row 1362 for (int i = 0; i < mNumRows; i++) { 1363 List<Integer> row = rows[i]; 1364 final int startSecondary = getRowStartSecondary(i) - mScrollOffsetSecondary; 1365 for (int j = 0, size = row.size(); j < size; j++) { 1366 final int position = row.get(j); 1367 final View view = getViewByPosition(position); 1368 final boolean layoutForward = getIsViewLayoutForward(view); 1369 int primaryDelta, start, end; 1370 1371 if (mOrientation == HORIZONTAL) { 1372 final int primarySize = view.getMeasuredWidth(); 1373 if (view.isLayoutRequested()) { 1374 measureChild(view, i); 1375 } 1376 if (layoutForward) { 1377 start = getViewMin(view); 1378 end = start + view.getMeasuredWidth(); 1379 primaryDelta = view.getMeasuredWidth() - primarySize; 1380 if (primaryDelta != 0) { 1381 for (int k = j + 1; k < size; k++) { 1382 getViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1383 } 1384 } 1385 } else { 1386 end = getViewMax(view); 1387 start = end - view.getMeasuredWidth(); 1388 primaryDelta = primarySize - view.getMeasuredWidth(); 1389 if (primaryDelta != 0) { 1390 for (int k = 0; k < j; k++) { 1391 getViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1392 } 1393 } 1394 } 1395 } else { 1396 final int primarySize = view.getMeasuredHeight(); 1397 if (view.isLayoutRequested()) { 1398 measureChild(view, i); 1399 } 1400 if (layoutForward) { 1401 start = getViewMin(view); 1402 end = start + view.getMeasuredHeight(); 1403 primaryDelta = view.getMeasuredHeight() - primarySize; 1404 if (primaryDelta != 0) { 1405 for (int k = j + 1; k < size; k++) { 1406 getViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1407 } 1408 } 1409 } else { 1410 end = getViewMax(view); 1411 start = end - view.getMeasuredHeight(); 1412 primaryDelta = primarySize - view.getMeasuredHeight(); 1413 if (primaryDelta != 0) { 1414 for (int k = 0; k < j; k++) { 1415 getViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1416 } 1417 } 1418 } 1419 } 1420 layoutChild(i, view, start, end, startSecondary); 1421 } 1422 } 1423 1424 updateRowsMinMax(); 1425 appendVisibleItems(); 1426 prependVisibleItems(); 1427 1428 updateRowsMinMax(); 1429 updateScrollMin(); 1430 updateScrollMax(); 1431 updateScrollSecondAxis(); 1432 1433 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1434 View focusView = getViewByPosition(mFocusPosition == NO_POSITION ? 0 : mFocusPosition); 1435 scrollToView(focusView, false); 1436 } 1437 } 1438 1439 // Lays out items based on the current scroll position 1440 @Override 1441 public void onLayoutChildren(RecyclerView.Adapter adapter, RecyclerView.Recycler recycler, 1442 boolean structureChanged, RecyclerView.State state) { 1443 if (DEBUG) { 1444 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1445 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1446 + " structureChanged " + structureChanged 1447 + " mForceFullLayout " + mForceFullLayout); 1448 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1449 } 1450 1451 if (mNumRows == 0) { 1452 // haven't done measure yet 1453 return; 1454 } 1455 final int itemCount = adapter.getItemCount(); 1456 if (itemCount < 0) { 1457 return; 1458 } 1459 1460 mInLayout = true; 1461 1462 // Track the old focus view so we can adjust our system scroll position 1463 // so that any scroll animations happening now will remain valid. 1464 int delta = 0, deltaSecondary = 0; 1465 if (mFocusPosition != NO_POSITION 1466 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1467 View focusView = getViewByPosition(mFocusPosition); 1468 if (focusView != null) { 1469 delta = mWindowAlignment.mainAxis().getSystemScrollPos( 1470 getViewCenter(focusView) + mScrollOffsetPrimary) - mScrollOffsetPrimary; 1471 deltaSecondary = 1472 mWindowAlignment.secondAxis().getSystemScrollPos( 1473 getViewCenterSecondary(focusView) + mScrollOffsetSecondary) 1474 - mScrollOffsetSecondary; 1475 } 1476 } 1477 1478 final boolean hasDoneFirstLayout = hasDoneFirstLayout(); 1479 if (!mLayoutEnabled) { 1480 discardLayoutInfo(); 1481 removeAllViews(); 1482 } else if (!structureChanged && !mForceFullLayout && hasDoneFirstLayout) { 1483 fastRelayout(); 1484 } else { 1485 boolean hadFocus = mBaseGridView.hasFocus(); 1486 1487 int newFocusPosition = init(adapter, recycler, mFocusPosition); 1488 if (DEBUG) { 1489 Log.v(getTag(), "mFocusPosition " + mFocusPosition + " newFocusPosition " 1490 + newFocusPosition); 1491 } 1492 1493 // depending on result of init(), either recreating everything 1494 // or try to reuse the row start positions near mFocusPosition 1495 if (mGrid.getSize() == 0) { 1496 // this is a fresh creating all items, starting from 1497 // mFocusPosition with a estimated row index. 1498 mGrid.setStart(newFocusPosition, StaggeredGrid.START_DEFAULT); 1499 1500 // Can't track the old focus view 1501 delta = deltaSecondary = 0; 1502 1503 } else { 1504 // mGrid remembers Locations for the column that 1505 // contains mFocusePosition and also mRows remembers start 1506 // positions of each row. 1507 // Manually re-create child views for that column 1508 int firstIndex = mGrid.getFirstIndex(); 1509 int lastIndex = mGrid.getLastIndex(); 1510 for (int i = firstIndex; i <= lastIndex; i++) { 1511 mGridProvider.createItem(i, mGrid.getLocation(i).row, true); 1512 } 1513 } 1514 // add visible views at end until reach the end of window 1515 appendVisibleItems(); 1516 // add visible views at front until reach the start of window 1517 prependVisibleItems(); 1518 // multiple rounds: scrollToView of first round may drag first/last child into 1519 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1520 int oldFirstVisible; 1521 int oldLastVisible; 1522 do { 1523 oldFirstVisible = mFirstVisiblePos; 1524 oldLastVisible = mLastVisiblePos; 1525 View focusView = getViewByPosition(newFocusPosition); 1526 // we need force to initialize the child view's position 1527 scrollToView(focusView, false); 1528 if (focusView != null && hadFocus) { 1529 focusView.requestFocus(); 1530 } 1531 appendVisibleItems(); 1532 prependVisibleItems(); 1533 removeInvisibleViewsAtFront(); 1534 removeInvisibleViewsAtEnd(); 1535 } while (mFirstVisiblePos != oldFirstVisible || mLastVisiblePos != oldLastVisible); 1536 } 1537 mForceFullLayout = false; 1538 1539 if (mLayoutEnabled) { 1540 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1541 scrollDirectionPrimary(-delta); 1542 scrollDirectionSecondary(-deltaSecondary); 1543 } 1544 appendVisibleItems(); 1545 prependVisibleItems(); 1546 removeInvisibleViewsAtFront(); 1547 removeInvisibleViewsAtEnd(); 1548 } 1549 1550 if (DEBUG) { 1551 StringWriter sw = new StringWriter(); 1552 PrintWriter pw = new PrintWriter(sw); 1553 mGrid.debugPrint(pw); 1554 Log.d(getTag(), sw.toString()); 1555 } 1556 1557 removeAndRecycleScrap(recycler); 1558 attemptAnimateLayoutChild(); 1559 1560 if (mRowSecondarySizeRefresh) { 1561 mRowSecondarySizeRefresh = false; 1562 } else { 1563 updateRowSecondarySizeRefresh(); 1564 } 1565 1566 if (!hasDoneFirstLayout) { 1567 dispatchChildSelected(); 1568 } 1569 mInLayout = false; 1570 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1571 } 1572 1573 private void offsetChildrenSecondary(int increment) { 1574 final int childCount = getChildCount(); 1575 if (mOrientation == HORIZONTAL) { 1576 for (int i = 0; i < childCount; i++) { 1577 getChildAt(i).offsetTopAndBottom(increment); 1578 } 1579 } else { 1580 for (int i = 0; i < childCount; i++) { 1581 getChildAt(i).offsetLeftAndRight(increment); 1582 } 1583 } 1584 mScrollOffsetSecondary -= increment; 1585 } 1586 1587 private void offsetChildrenPrimary(int increment) { 1588 final int childCount = getChildCount(); 1589 if (mOrientation == VERTICAL) { 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 mScrollOffsetPrimary -= increment; 1599 } 1600 1601 @Override 1602 public int scrollHorizontallyBy(int dx, Adapter adapter, Recycler recycler, 1603 RecyclerView.State state) { 1604 if (DEBUG) Log.v(TAG, "scrollHorizontallyBy " + dx); 1605 1606 if (mOrientation == HORIZONTAL) { 1607 return scrollDirectionPrimary(dx); 1608 } else { 1609 return scrollDirectionSecondary(dx); 1610 } 1611 } 1612 1613 @Override 1614 public int scrollVerticallyBy(int dy, Adapter adapter, Recycler recycler, 1615 RecyclerView.State state) { 1616 if (DEBUG) Log.v(TAG, "scrollVerticallyBy " + dy); 1617 if (mOrientation == VERTICAL) { 1618 return scrollDirectionPrimary(dy); 1619 } else { 1620 return scrollDirectionSecondary(dy); 1621 } 1622 } 1623 1624 // scroll in main direction may add/prune views 1625 private int scrollDirectionPrimary(int da) { 1626 offsetChildrenPrimary(-da); 1627 if (mInLayout) { 1628 return da; 1629 } 1630 1631 int childCount = getChildCount(); 1632 boolean updated; 1633 1634 if (da > 0) { 1635 appendVisibleItems(); 1636 } else if (da < 0) { 1637 prependVisibleItems(); 1638 } 1639 updated = getChildCount() > childCount; 1640 childCount = getChildCount(); 1641 1642 if (da > 0) { 1643 removeInvisibleViewsAtFront(); 1644 } else if (da < 0) { 1645 removeInvisibleViewsAtEnd(); 1646 } 1647 updated |= getChildCount() < childCount; 1648 1649 attemptAnimateLayoutChild(); 1650 if (updated) { 1651 updateRowSecondarySizeRefresh(); 1652 } 1653 1654 mBaseGridView.invalidate(); 1655 return da; 1656 } 1657 1658 // scroll in second direction will not add/prune views 1659 private int scrollDirectionSecondary(int dy) { 1660 offsetChildrenSecondary(-dy); 1661 mBaseGridView.invalidate(); 1662 return dy; 1663 } 1664 1665 private void updateScrollMax() { 1666 if (mLastVisiblePos >= 0 && mLastVisiblePos == mAdapter.getItemCount() - 1) { 1667 int maxEdge = Integer.MIN_VALUE; 1668 for (int i = 0; i < mRows.length; i++) { 1669 if (mRows[i].high > maxEdge) { 1670 maxEdge = mRows[i].high; 1671 } 1672 } 1673 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1674 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge); 1675 } 1676 } 1677 1678 private void updateScrollMin() { 1679 if (mFirstVisiblePos == 0) { 1680 int minEdge = Integer.MAX_VALUE; 1681 for (int i = 0; i < mRows.length; i++) { 1682 if (mRows[i].low < minEdge) { 1683 minEdge = mRows[i].low; 1684 } 1685 } 1686 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1687 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge); 1688 } 1689 } 1690 1691 private void updateScrollSecondAxis() { 1692 mWindowAlignment.secondAxis().setMinEdge(0); 1693 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1694 } 1695 1696 private void initScrollController() { 1697 mWindowAlignment.horizontal.setSize(getWidth()); 1698 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1699 mWindowAlignment.vertical.setSize(getHeight()); 1700 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1701 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1702 mWindowAlignment.mainAxis().invalidateScrollMin(); 1703 mWindowAlignment.mainAxis().invalidateScrollMax(); 1704 1705 if (DEBUG) { 1706 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1707 + " mWindowAlignment " + mWindowAlignment); 1708 } 1709 } 1710 1711 public void setSelection(RecyclerView parent, int position) { 1712 setSelection(parent, position, false); 1713 } 1714 1715 public void setSelectionSmooth(RecyclerView parent, int position) { 1716 setSelection(parent, position, true); 1717 } 1718 1719 public int getSelection() { 1720 return mFocusPosition; 1721 } 1722 1723 public void setSelection(RecyclerView parent, int position, boolean smooth) { 1724 if (mFocusPosition == position) { 1725 return; 1726 } 1727 View view = getViewByPosition(position); 1728 if (view != null) { 1729 scrollToView(view, smooth); 1730 } else { 1731 boolean right = position > mFocusPosition; 1732 mFocusPosition = position; 1733 if (!mLayoutEnabled) { 1734 return; 1735 } 1736 if (smooth) { 1737 if (!hasDoneFirstLayout()) { 1738 Log.w(getTag(), "setSelectionSmooth should " + 1739 "not be called before first layout pass"); 1740 return; 1741 } 1742 if (right) { 1743 appendVisibleItems(); 1744 } else { 1745 prependVisibleItems(); 1746 } 1747 scrollToView(getViewByPosition(position), smooth); 1748 } else { 1749 mForceFullLayout = true; 1750 parent.requestLayout(); 1751 } 1752 } 1753 } 1754 1755 @Override 1756 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 1757 boolean needsLayout = false; 1758 if (itemCount != 0) { 1759 if (mFirstVisiblePos < 0) { 1760 needsLayout = true; 1761 } else if (!(positionStart > mLastVisiblePos + 1 || 1762 positionStart + itemCount < mFirstVisiblePos - 1)) { 1763 needsLayout = true; 1764 } 1765 } 1766 if (needsLayout) { 1767 recyclerView.requestLayout(); 1768 } 1769 } 1770 1771 @Override 1772 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 1773 if (mFocusSearchDisabled) { 1774 return true; 1775 } 1776 if (!mInLayout) { 1777 scrollToView(child, true); 1778 } 1779 return true; 1780 } 1781 1782 @Override 1783 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 1784 boolean immediate) { 1785 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 1786 return false; 1787 } 1788 1789 int getScrollOffsetX() { 1790 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 1791 } 1792 1793 int getScrollOffsetY() { 1794 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 1795 } 1796 1797 public void getViewSelectedOffsets(View view, int[] offsets) { 1798 int scrollOffsetX = getScrollOffsetX(); 1799 int scrollOffsetY = getScrollOffsetY(); 1800 int viewCenterX = scrollOffsetX + getViewCenterX(view); 1801 int viewCenterY = scrollOffsetY + getViewCenterY(view); 1802 offsets[0] = mWindowAlignment.horizontal.getSystemScrollPos(viewCenterX) - scrollOffsetX; 1803 offsets[1] = mWindowAlignment.vertical.getSystemScrollPos(viewCenterY) - scrollOffsetY; 1804 } 1805 1806 /** 1807 * Scroll to a given child view and change mFocusPosition. 1808 */ 1809 private void scrollToView(View view, boolean smooth) { 1810 int newFocusPosition = getPositionByView(view); 1811 if (mInLayout || newFocusPosition != mFocusPosition) { 1812 mFocusPosition = newFocusPosition; 1813 dispatchChildSelected(); 1814 } 1815 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 1816 mBaseGridView.invalidate(); 1817 } 1818 if (view == null) { 1819 return; 1820 } 1821 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 1822 // transfer focus to the child if it does not have focus yet (e.g. triggered 1823 // by setSelection()) 1824 view.requestFocus(); 1825 } 1826 switch (mFocusScrollStrategy) { 1827 case BaseGridView.FOCUS_SCROLL_ALIGNED: 1828 default: 1829 scrollToAlignedPosition(view, smooth); 1830 break; 1831 case BaseGridView.FOCUS_SCROLL_ITEM: 1832 case BaseGridView.FOCUS_SCROLL_PAGE: 1833 scrollItemOrPage(view, smooth); 1834 break; 1835 } 1836 } 1837 1838 private void scrollItemOrPage(View view, boolean smooth) { 1839 int pos = getPositionByView(view); 1840 int viewMin = getViewMin(view); 1841 int viewMax = getViewMax(view); 1842 // we either align "firstView" to left/top padding edge 1843 // or align "lastView" to right/bottom padding edge 1844 View firstView = null; 1845 View lastView = null; 1846 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 1847 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 1848 final int row = mGrid.getLocation(pos).row; 1849 if (viewMin < paddingLow) { 1850 // view enters low padding area: 1851 firstView = view; 1852 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1853 // scroll one "page" left/top, 1854 // align first visible item of the "page" at the low padding edge. 1855 while (!prependOneVisibleItem()) { 1856 List<Integer> positions = 1857 mGrid.getItemPositionsInRows(mFirstVisiblePos, pos)[row]; 1858 firstView = getViewByPosition(positions.get(0)); 1859 if (viewMax - getViewMin(firstView) > clientSize) { 1860 if (positions.size() > 1) { 1861 firstView = getViewByPosition(positions.get(1)); 1862 } 1863 break; 1864 } 1865 } 1866 } 1867 } else if (viewMax > clientSize + paddingLow) { 1868 // view enters high padding area: 1869 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1870 // scroll whole one page right/bottom, align view at the low padding edge. 1871 firstView = view; 1872 do { 1873 List<Integer> positions = 1874 mGrid.getItemPositionsInRows(pos, mLastVisiblePos)[row]; 1875 lastView = getViewByPosition(positions.get(positions.size() - 1)); 1876 if (getViewMax(lastView) - viewMin > clientSize) { 1877 lastView = null; 1878 break; 1879 } 1880 } while (!appendOneVisibleItem()); 1881 if (lastView != null) { 1882 // however if we reached end, we should align last view. 1883 firstView = null; 1884 } 1885 } else { 1886 lastView = view; 1887 } 1888 } 1889 int scrollPrimary = 0; 1890 int scrollSecondary = 0; 1891 if (firstView != null) { 1892 scrollPrimary = getViewMin(firstView) - paddingLow; 1893 } else if (lastView != null) { 1894 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 1895 } 1896 View secondaryAlignedView; 1897 if (firstView != null) { 1898 secondaryAlignedView = firstView; 1899 } else if (lastView != null) { 1900 secondaryAlignedView = lastView; 1901 } else { 1902 secondaryAlignedView = view; 1903 } 1904 int viewCenterSecondary = mScrollOffsetSecondary + 1905 getViewCenterSecondary(secondaryAlignedView); 1906 mWindowAlignment.secondAxis().updateScrollCenter(viewCenterSecondary); 1907 scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(); 1908 scrollSecondary -= mScrollOffsetSecondary; 1909 scrollGrid(scrollPrimary, scrollSecondary, smooth); 1910 } 1911 1912 private void scrollToAlignedPosition(View view, boolean smooth) { 1913 int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 1914 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 1915 if (DEBUG) { 1916 Log.v(getTag(), "scrollAligned smooth=" + smooth + " pos=" + mFocusPosition + " " 1917 + viewCenterPrimary +","+viewCenterSecondary + " " + mWindowAlignment); 1918 } 1919 1920 if (mInLayout || viewCenterPrimary != mWindowAlignment.mainAxis().getScrollCenter() 1921 || viewCenterSecondary != mWindowAlignment.secondAxis().getScrollCenter()) { 1922 mWindowAlignment.mainAxis().updateScrollCenter(viewCenterPrimary); 1923 mWindowAlignment.secondAxis().updateScrollCenter(viewCenterSecondary); 1924 int scrollPrimary = mWindowAlignment.mainAxis().getSystemScrollPos(); 1925 int scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(); 1926 if (DEBUG) { 1927 Log.v(getTag(), "scrollAligned " + scrollPrimary + " " + scrollSecondary 1928 +" " + mWindowAlignment); 1929 } 1930 1931 scrollPrimary -= mScrollOffsetPrimary; 1932 scrollSecondary -= mScrollOffsetSecondary; 1933 1934 scrollGrid(scrollPrimary, scrollSecondary, smooth); 1935 } 1936 } 1937 1938 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 1939 if (mInLayout) { 1940 scrollDirectionPrimary(scrollPrimary); 1941 scrollDirectionSecondary(scrollSecondary); 1942 } else { 1943 int scrollX; 1944 int scrollY; 1945 if (mOrientation == HORIZONTAL) { 1946 scrollX = scrollPrimary; 1947 scrollY = scrollSecondary; 1948 } else { 1949 scrollX = scrollSecondary; 1950 scrollY = scrollPrimary; 1951 } 1952 if (smooth) { 1953 mBaseGridView.smoothScrollBy(scrollX, scrollY); 1954 } else { 1955 mBaseGridView.scrollBy(scrollX, scrollY); 1956 } 1957 } 1958 } 1959 1960 public void setAnimateChildLayout(boolean animateChildLayout) { 1961 mAnimateChildLayout = animateChildLayout; 1962 for (int i = 0, c = getChildCount(); i < c; i++) { 1963 View v = getChildAt(i); 1964 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1965 if (!mAnimateChildLayout) { 1966 p.endAnimate(); 1967 } else { 1968 // record initial location values 1969 p.mFirstAttached = true; 1970 p.startAnimate(this, v, 0); 1971 } 1972 } 1973 } 1974 1975 private void attemptAnimateLayoutChild() { 1976 if (!mAnimateChildLayout) { 1977 return; 1978 } 1979 for (int i = 0, c = getChildCount(); i < c; i++) { 1980 // TODO: start delay can be staggered 1981 View v = getChildAt(i); 1982 ((LayoutParams) v.getLayoutParams()).startAnimate(this, v, 0); 1983 } 1984 } 1985 1986 public boolean isChildLayoutAnimated() { 1987 return mAnimateChildLayout; 1988 } 1989 1990 public void setChildLayoutAnimationInterpolator(Interpolator interpolator) { 1991 mAnimateLayoutChildInterpolator = interpolator; 1992 } 1993 1994 public Interpolator getChildLayoutAnimationInterpolator() { 1995 return mAnimateLayoutChildInterpolator; 1996 } 1997 1998 public void setChildLayoutAnimationDuration(long duration) { 1999 mAnimateLayoutChildDuration = duration; 2000 } 2001 2002 public long getChildLayoutAnimationDuration() { 2003 return mAnimateLayoutChildDuration; 2004 } 2005 2006 private int findImmediateChildIndex(View view) { 2007 while (view != null && view != mBaseGridView) { 2008 int index = mBaseGridView.indexOfChild(view); 2009 if (index >= 0) { 2010 return index; 2011 } 2012 view = (View) view.getParent(); 2013 } 2014 return NO_POSITION; 2015 } 2016 2017 void setFocusSearchDisabled(boolean disabled) { 2018 mFocusSearchDisabled = disabled; 2019 } 2020 2021 boolean isFocusSearchDisabled() { 2022 return mFocusSearchDisabled; 2023 } 2024 2025 @Override 2026 public View onInterceptFocusSearch(View focused, int direction) { 2027 if (mFocusSearchDisabled) { 2028 return focused; 2029 } 2030 return null; 2031 } 2032 2033 boolean hasNextViewInSameRow(int pos) { 2034 if (mGrid == null || pos == NO_POSITION) { 2035 return false; 2036 } 2037 final int focusedRow = mGrid.getLocation(pos).row; 2038 for (int i = 0, count = getChildCount(); i < count; i++) { 2039 int position = getPositionByIndex(i); 2040 StaggeredGrid.Location loc = mGrid.getLocation(position); 2041 if (loc != null && loc.row == focusedRow) { 2042 if (position > pos) { 2043 return true; 2044 } 2045 } 2046 } 2047 return false; 2048 } 2049 2050 boolean hasPreviousViewInSameRow(int pos) { 2051 if (mGrid == null || pos == NO_POSITION) { 2052 return false; 2053 } 2054 final int focusedRow = mGrid.getLocation(pos).row; 2055 for (int i = getChildCount() - 1; i >= 0; i--) { 2056 int position = getPositionByIndex(i); 2057 StaggeredGrid.Location loc = mGrid.getLocation(position); 2058 if (loc != null && loc.row == focusedRow) { 2059 if (position < pos) { 2060 return true; 2061 } 2062 } 2063 } 2064 return false; 2065 } 2066 2067 @Override 2068 public boolean onAddFocusables(RecyclerView recyclerView, 2069 ArrayList<View> views, int direction, int focusableMode) { 2070 if (mFocusSearchDisabled) { 2071 return true; 2072 } 2073 // If this viewgroup or one of its children currently has focus then we 2074 // consider our children for focus searching in main direction on the same row. 2075 // If this viewgroup has no focus and using focus align, we want the system 2076 // to ignore our children and pass focus to the viewgroup, which will pass 2077 // focus on to its children appropriately. 2078 // If this viewgroup has no focus and not using focus align, we want to 2079 // consider the child that does not overlap with padding area. 2080 if (recyclerView.hasFocus()) { 2081 final int movement = getMovement(direction); 2082 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2083 // Move on secondary direction uses default addFocusables(). 2084 return false; 2085 } 2086 final View focused = recyclerView.findFocus(); 2087 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2088 // Add focusables of focused item. 2089 if (focusedPos != NO_POSITION) { 2090 getViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2091 } 2092 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2093 mGrid.getLocation(focusedPos).row : NO_POSITION; 2094 // Add focusables of next neighbor of same row on the focus search direction. 2095 if (mGrid != null) { 2096 final int focusableCount = views.size(); 2097 for (int i = 0, count = getChildCount(); i < count; i++) { 2098 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2099 final View child = getChildAt(index); 2100 if (child.getVisibility() != View.VISIBLE) { 2101 continue; 2102 } 2103 int position = getPositionByIndex(index); 2104 StaggeredGrid.Location loc = mGrid.getLocation(position); 2105 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2106 if (focusedPos == NO_POSITION || 2107 (movement == NEXT_ITEM && position > focusedPos) 2108 || (movement == PREV_ITEM && position < focusedPos)) { 2109 child.addFocusables(views, direction, focusableMode); 2110 if (views.size() > focusableCount) { 2111 break; 2112 } 2113 } 2114 } 2115 } 2116 } 2117 } else { 2118 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2119 // adding views not overlapping padding area to avoid scrolling in gaining focus 2120 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2121 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2122 int focusableCount = views.size(); 2123 for (int i = 0, count = getChildCount(); i < count; i++) { 2124 View child = getChildAt(i); 2125 if (child.getVisibility() == View.VISIBLE) { 2126 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2127 child.addFocusables(views, direction, focusableMode); 2128 } 2129 } 2130 } 2131 // if we cannot find any, then just add all children. 2132 if (views.size() == focusableCount) { 2133 for (int i = 0, count = getChildCount(); i < count; i++) { 2134 View child = getChildAt(i); 2135 if (child.getVisibility() == View.VISIBLE) { 2136 child.addFocusables(views, direction, focusableMode); 2137 } 2138 } 2139 if (views.size() != focusableCount) { 2140 return true; 2141 } 2142 } else { 2143 return true; 2144 } 2145 // if still cannot find any, fall through and add itself 2146 } 2147 if (recyclerView.isFocusable()) { 2148 views.add(recyclerView); 2149 } 2150 } 2151 return true; 2152 } 2153 2154 @Override 2155 public View onFocusSearchFailed(View focused, int direction, Adapter adapter, 2156 Recycler recycler) { 2157 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2158 2159 View view = null; 2160 int movement = getMovement(direction); 2161 final FocusFinder ff = FocusFinder.getInstance(); 2162 if (movement == NEXT_ITEM) { 2163 while (view == null && !appendOneVisibleItem()) { 2164 view = ff.findNextFocus(mBaseGridView, focused, direction); 2165 } 2166 } else if (movement == PREV_ITEM){ 2167 while (view == null && !prependOneVisibleItem()) { 2168 view = ff.findNextFocus(mBaseGridView, focused, direction); 2169 } 2170 } 2171 if (view == null) { 2172 // returning the same view to prevent focus lost when scrolling past the end of the list 2173 if (movement == PREV_ITEM) { 2174 view = mFocusOutFront ? null : focused; 2175 } else if (movement == NEXT_ITEM){ 2176 view = mFocusOutEnd ? null : focused; 2177 } 2178 } 2179 if (DEBUG) Log.v(getTag(), "returning view " + view); 2180 return view; 2181 } 2182 2183 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2184 Rect previouslyFocusedRect) { 2185 switch (mFocusScrollStrategy) { 2186 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2187 default: 2188 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2189 direction, previouslyFocusedRect); 2190 case BaseGridView.FOCUS_SCROLL_PAGE: 2191 case BaseGridView.FOCUS_SCROLL_ITEM: 2192 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2193 direction, previouslyFocusedRect); 2194 } 2195 } 2196 2197 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2198 int direction, Rect previouslyFocusedRect) { 2199 View view = getViewByPosition(mFocusPosition); 2200 if (view != null) { 2201 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2202 if (!result && DEBUG) { 2203 Log.w(getTag(), "failed to request focus on " + view); 2204 } 2205 return result; 2206 } 2207 return false; 2208 } 2209 2210 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2211 int direction, Rect previouslyFocusedRect) { 2212 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2213 int index; 2214 int increment; 2215 int end; 2216 int count = getChildCount(); 2217 if ((direction & View.FOCUS_FORWARD) != 0) { 2218 index = 0; 2219 increment = 1; 2220 end = count; 2221 } else { 2222 index = count - 1; 2223 increment = -1; 2224 end = -1; 2225 } 2226 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2227 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2228 for (int i = index; i != end; i += increment) { 2229 View child = getChildAt(i); 2230 if (child.getVisibility() == View.VISIBLE) { 2231 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2232 if (child.requestFocus(direction, previouslyFocusedRect)) { 2233 return true; 2234 } 2235 } 2236 } 2237 } 2238 return false; 2239 } 2240 2241 private final static int PREV_ITEM = 0; 2242 private final static int NEXT_ITEM = 1; 2243 private final static int PREV_ROW = 2; 2244 private final static int NEXT_ROW = 3; 2245 2246 private int getMovement(int direction) { 2247 int movement = View.FOCUS_LEFT; 2248 2249 if (mOrientation == HORIZONTAL) { 2250 switch(direction) { 2251 case View.FOCUS_LEFT: 2252 movement = PREV_ITEM; 2253 break; 2254 case View.FOCUS_RIGHT: 2255 movement = NEXT_ITEM; 2256 break; 2257 case View.FOCUS_UP: 2258 movement = PREV_ROW; 2259 break; 2260 case View.FOCUS_DOWN: 2261 movement = NEXT_ROW; 2262 break; 2263 } 2264 } else if (mOrientation == VERTICAL) { 2265 switch(direction) { 2266 case View.FOCUS_LEFT: 2267 movement = PREV_ROW; 2268 break; 2269 case View.FOCUS_RIGHT: 2270 movement = NEXT_ROW; 2271 break; 2272 case View.FOCUS_UP: 2273 movement = PREV_ITEM; 2274 break; 2275 case View.FOCUS_DOWN: 2276 movement = NEXT_ITEM; 2277 break; 2278 } 2279 } 2280 2281 return movement; 2282 } 2283 2284 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2285 int focusIndex = getIndexByPosition(mFocusPosition); 2286 if (focusIndex == NO_POSITION) { 2287 return i; 2288 } 2289 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2290 // drawing order is 0 1 2 3 9 8 7 6 5 4 2291 if (i < focusIndex) { 2292 return i; 2293 } else if (i < childCount - 1) { 2294 return focusIndex + childCount - 1 - i; 2295 } else { 2296 return focusIndex; 2297 } 2298 } 2299 2300 @Override 2301 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2302 RecyclerView.Adapter newAdapter) { 2303 discardLayoutInfo(); 2304 super.onAdapterChanged(oldAdapter, newAdapter); 2305 } 2306 2307 private void discardLayoutInfo() { 2308 mGrid = null; 2309 mRows = null; 2310 mRowSizeSecondary = null; 2311 mRowSecondarySizeRefresh = false; 2312 } 2313 2314 public void setLayoutEnabled(boolean layoutEnabled) { 2315 if (mLayoutEnabled != layoutEnabled) { 2316 mLayoutEnabled = layoutEnabled; 2317 requestLayout(); 2318 } 2319 } 2320} 2321