GridLayoutManager.java revision e43e9266c4b7e4902fefb5d2a0cacca90a3d2681
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 int getOpticalLeftInset() { 151 return mLeftInset; 152 } 153 154 int getOpticalRightInset() { 155 return mRighInset; 156 } 157 158 int getOpticalTopInset() { 159 return mTopInset; 160 } 161 162 int getOpticalBottomInset() { 163 return mBottomInset; 164 } 165 166 void setAlignX(int alignX) { 167 mAlignX = alignX; 168 } 169 170 void setAlignY(int alignY) { 171 mAlignY = alignY; 172 } 173 174 void setOpticalInsets(int leftInset, int topInset, int rightInset, int bottomInset) { 175 mLeftInset = leftInset; 176 mTopInset = topInset; 177 mRighInset = rightInset; 178 mBottomInset = bottomInset; 179 } 180 181 private TimeAnimator.TimeListener mTimeListener = new TimeAnimator.TimeListener() { 182 @Override 183 public void onTimeUpdate(TimeAnimator animation, long totalTime, long deltaTime) { 184 if (mView == null) { 185 return; 186 } 187 if (totalTime >= mDuration) { 188 endAnimate(); 189 } else { 190 float fraction = (float) (totalTime / (double)mDuration); 191 float fractionToEnd = 1 - mAnimator 192 .getInterpolator().getInterpolation(fraction); 193 if (mOrientation == HORIZONTAL) { 194 if (mLayoutForward) { 195 mView.setTranslationX(fractionToEnd * mAnimationStartTranslationX); 196 } else { 197 mView.setTranslationX(fractionToEnd * mAnimationStartTranslationX - 198 fractionToEnd * (mView.getMeasuredWidth() - mSize)); 199 } 200 } else { 201 if (mLayoutForward) { 202 mView.setTranslationY(fractionToEnd * mAnimationStartTranslationY); 203 } else { 204 mView.setTranslationY(fractionToEnd * mAnimationStartTranslationY - 205 fractionToEnd * (mView.getMeasuredHeight() - mSize)); 206 } 207 } 208 invalidateItemDecoration(); 209 } 210 } 211 }; 212 213 void recordStart(int orientation, View view) { 214 mViewX = getOpticalLeft(view); 215 mViewY = getOpticalTop(view); 216 mOrientation = orientation; 217 mSize = mOrientation == HORIZONTAL ? view.getMeasuredWidth() : view.getMeasuredHeight(); 218 } 219 220 void startAnimate(View view, 221 long duration, long startDelay, Interpolator interpolator) { 222 if (mFirstAttachedInLayout) { 223 // if the view is just attached in layout pass, do not run animation 224 mFirstAttachedInLayout = false; 225 return; 226 } 227 int newViewX = getOpticalLeft(view); 228 int newViewY = getOpticalTop(view); 229 if (newViewX != mViewX || newViewY != mViewY) { 230 if (mAnimator == null) { 231 mAnimator = new TimeAnimator(); 232 mAnimator.setTimeListener(mTimeListener); 233 } 234 mView = view; 235 mAnimationStartTranslationX = mView.getTranslationX(); 236 mAnimationStartTranslationY = mView.getTranslationY(); 237 mAnimator.cancel(); 238 mAnimationStartTranslationX += mViewX - newViewX; 239 mAnimationStartTranslationY += mViewY - newViewY; 240 mDuration = duration; 241 mAnimator.setDuration(mDuration); 242 mAnimator.setInterpolator(interpolator); 243 mAnimator.setStartDelay(startDelay); 244 mAnimator.start(); 245 // put it at initial location 246 mTimeListener.onTimeUpdate(mAnimator, 0, 0); 247 } 248 } 249 250 void endAnimate() { 251 if (mAnimator != null) { 252 mAnimator.end(); 253 } 254 if (mView != null) { 255 mSize = mOrientation == HORIZONTAL ? 256 mView.getMeasuredWidth() : mView.getMeasuredHeight(); 257 mView.setTranslationX(0); 258 mView.setTranslationY(0); 259 mView = null; 260 } 261 } 262 263 private void invalidateItemDecoration() { 264 ViewParent parent = mView.getParent(); 265 if (parent instanceof RecyclerView) { 266 // TODO: we only need invalidate parent if it has ItemDecoration 267 ((RecyclerView) parent).invalidate(); 268 } 269 } 270 } 271 272 private static final String TAG = "GridLayoutManager"; 273 private static final boolean DEBUG = false; 274 275 private static final Interpolator sDefaultAnimationChildLayoutInterpolator 276 = new DecelerateInterpolator(); 277 278 private static final long DEFAULT_CHILD_ANIMATION_DURATION_MS = 250; 279 280 private String getTag() { 281 return TAG + ":" + mBaseGridView.getId(); 282 } 283 284 private final BaseGridView mBaseGridView; 285 286 /** 287 * The orientation of a "row". 288 */ 289 private int mOrientation = HORIZONTAL; 290 291 private RecyclerView.Adapter mAdapter; 292 private RecyclerView.Recycler mRecycler; 293 294 private boolean mInLayout = false; 295 296 private OnChildSelectedListener mChildSelectedListener = null; 297 298 /** 299 * The focused position, it's not the currently visually aligned position 300 * but it is the final position that we intend to focus on. If there are 301 * multiple setSelection() called, mFocusPosition saves last value. 302 */ 303 private int mFocusPosition = NO_POSITION; 304 305 /** 306 * Force a full layout under certain situations. 307 */ 308 private boolean mForceFullLayout; 309 310 /** 311 * True if layout is enabled. 312 */ 313 private boolean mLayoutEnabled = true; 314 315 /** 316 * The scroll offsets of the viewport relative to the entire view. 317 */ 318 private int mScrollOffsetPrimary; 319 private int mScrollOffsetSecondary; 320 321 /** 322 * User-specified row height/column width. Can be WRAP_CONTENT. 323 */ 324 private int mRowSizeSecondaryRequested; 325 326 /** 327 * The fixed size of each grid item in the secondary direction. This corresponds to 328 * the row height, equal for all rows. Grid items may have variable length 329 * in the primary direction. 330 */ 331 private int mFixedRowSizeSecondary; 332 333 /** 334 * Tracks the secondary size of each row. 335 */ 336 private int[] mRowSizeSecondary; 337 338 /** 339 * Flag controlling whether the current/next layout should 340 * be updating the secondary size of rows. 341 */ 342 private boolean mRowSecondarySizeRefresh; 343 344 /** 345 * The maximum measured size of the view. 346 */ 347 private int mMaxSizeSecondary; 348 349 /** 350 * Margin between items. 351 */ 352 private int mHorizontalMargin; 353 /** 354 * Margin between items vertically. 355 */ 356 private int mVerticalMargin; 357 /** 358 * Margin in main direction. 359 */ 360 private int mMarginPrimary; 361 /** 362 * Margin in second direction. 363 */ 364 private int mMarginSecondary; 365 /** 366 * How to position child in secondary direction. 367 */ 368 private int mGravity = Gravity.LEFT | Gravity.TOP; 369 /** 370 * The number of rows in the grid. 371 */ 372 private int mNumRows; 373 /** 374 * Number of rows requested, can be 0 to be determined by parent size and 375 * rowHeight. 376 */ 377 private int mNumRowsRequested = 1; 378 379 /** 380 * Tracking start/end position of each row for visible items. 381 */ 382 private StaggeredGrid.Row[] mRows; 383 384 /** 385 * Saves grid information of each view. 386 */ 387 private StaggeredGrid mGrid; 388 /** 389 * Position of first item (included) that has attached views. 390 */ 391 private int mFirstVisiblePos; 392 /** 393 * Position of last item (included) that has attached views. 394 */ 395 private int mLastVisiblePos; 396 397 /** 398 * Focus Scroll strategy. 399 */ 400 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 401 /** 402 * Defines how item view is aligned in the window. 403 */ 404 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 405 406 /** 407 * Defines how item view is aligned. 408 */ 409 private final ItemAlignment mItemAlignment = new ItemAlignment(); 410 411 /** 412 * Dimensions of the view, width or height depending on orientation. 413 */ 414 private int mSizePrimary; 415 416 /** 417 * Allow DPAD key to navigate out at the front of the View (where position = 0), 418 * default is false. 419 */ 420 private boolean mFocusOutFront; 421 422 /** 423 * Allow DPAD key to navigate out at the end of the view, default is false. 424 */ 425 private boolean mFocusOutEnd; 426 427 /** 428 * True if focus search is disabled. 429 */ 430 private boolean mFocusSearchDisabled; 431 432 /** 433 * Animate layout changes from a child resizing or adding/removing a child. 434 */ 435 private boolean mAnimateChildLayout = true; 436 437 /** 438 * True if prune child, might be disabled during transition. 439 */ 440 private boolean mPruneChild = true; 441 442 /** 443 * Interpolator used to animate layout of children. 444 */ 445 private Interpolator mAnimateLayoutChildInterpolator = sDefaultAnimationChildLayoutInterpolator; 446 447 /** 448 * Duration used to animate layout of children. 449 */ 450 private long mAnimateLayoutChildDuration = DEFAULT_CHILD_ANIMATION_DURATION_MS; 451 452 public GridLayoutManager(BaseGridView baseGridView) { 453 mBaseGridView = baseGridView; 454 } 455 456 public void setOrientation(int orientation) { 457 if (orientation != HORIZONTAL && orientation != VERTICAL) { 458 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 459 return; 460 } 461 462 mOrientation = orientation; 463 mWindowAlignment.setOrientation(orientation); 464 mItemAlignment.setOrientation(orientation); 465 mForceFullLayout = true; 466 } 467 468 public int getFocusScrollStrategy() { 469 return mFocusScrollStrategy; 470 } 471 472 public void setFocusScrollStrategy(int focusScrollStrategy) { 473 mFocusScrollStrategy = focusScrollStrategy; 474 } 475 476 public void setWindowAlignment(int windowAlignment) { 477 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 478 } 479 480 public int getWindowAlignment() { 481 return mWindowAlignment.mainAxis().getWindowAlignment(); 482 } 483 484 public void setWindowAlignmentOffset(int alignmentOffset) { 485 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 486 } 487 488 public int getWindowAlignmentOffset() { 489 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 490 } 491 492 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 493 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 494 } 495 496 public float getWindowAlignmentOffsetPercent() { 497 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 498 } 499 500 public void setItemAlignmentOffset(int alignmentOffset) { 501 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 502 updateChildAlignments(); 503 } 504 505 public int getItemAlignmentOffset() { 506 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 507 } 508 509 public void setItemAlignmentOffsetWithPadding(boolean withPadding) { 510 mItemAlignment.mainAxis().setItemAlignmentOffsetWithPadding(withPadding); 511 updateChildAlignments(); 512 } 513 514 public boolean isItemAlignmentOffsetWithPadding() { 515 return mItemAlignment.mainAxis().isItemAlignmentOffsetWithPadding(); 516 } 517 518 public void setItemAlignmentOffsetPercent(float offsetPercent) { 519 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 520 updateChildAlignments(); 521 } 522 523 public float getItemAlignmentOffsetPercent() { 524 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 525 } 526 527 public void setItemAlignmentViewId(int viewId) { 528 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 529 updateChildAlignments(); 530 } 531 532 public int getItemAlignmentViewId() { 533 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 534 } 535 536 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 537 mFocusOutFront = throughFront; 538 mFocusOutEnd = throughEnd; 539 } 540 541 public void setNumRows(int numRows) { 542 if (numRows < 0) throw new IllegalArgumentException(); 543 mNumRowsRequested = numRows; 544 mForceFullLayout = true; 545 } 546 547 /** 548 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 549 */ 550 public void setRowHeight(int height) { 551 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 552 mRowSizeSecondaryRequested = height; 553 } else { 554 throw new IllegalArgumentException("Invalid row height: " + height); 555 } 556 } 557 558 public void setItemMargin(int margin) { 559 mVerticalMargin = mHorizontalMargin = margin; 560 mMarginPrimary = mMarginSecondary = margin; 561 } 562 563 public void setVerticalMargin(int margin) { 564 if (mOrientation == HORIZONTAL) { 565 mMarginSecondary = mVerticalMargin = margin; 566 } else { 567 mMarginPrimary = mVerticalMargin = margin; 568 } 569 } 570 571 public void setHorizontalMargin(int margin) { 572 if (mOrientation == HORIZONTAL) { 573 mMarginPrimary = mHorizontalMargin = margin; 574 } else { 575 mMarginSecondary = mHorizontalMargin = margin; 576 } 577 } 578 579 public int getVerticalMargin() { 580 return mVerticalMargin; 581 } 582 583 public int getHorizontalMargin() { 584 return mHorizontalMargin; 585 } 586 587 public void setGravity(int gravity) { 588 mGravity = gravity; 589 } 590 591 protected boolean hasDoneFirstLayout() { 592 return mGrid != null; 593 } 594 595 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 596 mChildSelectedListener = listener; 597 } 598 599 private int getPositionByView(View view) { 600 return getPositionByIndex(mBaseGridView.indexOfChild(view)); 601 } 602 603 private int getPositionByIndex(int index) { 604 if (index < 0) { 605 return NO_POSITION; 606 } 607 return mFirstVisiblePos + index; 608 } 609 610 private View getViewByPosition(int position) { 611 int index = getIndexByPosition(position); 612 if (index < 0) { 613 return null; 614 } 615 return getChildAt(index); 616 } 617 618 private int getIndexByPosition(int position) { 619 if (mFirstVisiblePos < 0 || 620 position < mFirstVisiblePos || position > mLastVisiblePos) { 621 return NO_POSITION; 622 } 623 return position - mFirstVisiblePos; 624 } 625 626 private void dispatchChildSelected() { 627 if (mChildSelectedListener == null) { 628 return; 629 } 630 631 View view = getViewByPosition(mFocusPosition); 632 633 if (mFocusPosition != NO_POSITION) { 634 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 635 mAdapter.getItemId(mFocusPosition)); 636 } else { 637 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 638 } 639 } 640 641 @Override 642 public boolean canScrollHorizontally() { 643 // We can scroll horizontally if we have horizontal orientation, or if 644 // we are vertical and have more than one column. 645 return mOrientation == HORIZONTAL || mNumRows > 1; 646 } 647 648 @Override 649 public boolean canScrollVertically() { 650 // We can scroll vertically if we have vertical orientation, or if we 651 // are horizontal and have more than one row. 652 return mOrientation == VERTICAL || mNumRows > 1; 653 } 654 655 @Override 656 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 657 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 658 ViewGroup.LayoutParams.WRAP_CONTENT); 659 } 660 661 @Override 662 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 663 return new LayoutParams(context, attrs); 664 } 665 666 @Override 667 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 668 if (lp instanceof LayoutParams) { 669 return new LayoutParams((LayoutParams) lp); 670 } else if (lp instanceof RecyclerView.LayoutParams) { 671 return new LayoutParams((RecyclerView.LayoutParams) lp); 672 } else if (lp instanceof MarginLayoutParams) { 673 return new LayoutParams((MarginLayoutParams) lp); 674 } else { 675 return new LayoutParams(lp); 676 } 677 } 678 679 protected View getViewForPosition(int position) { 680 View v = mRecycler.getViewForPosition(mAdapter, position); 681 if (v != null) { 682 ((LayoutParams) v.getLayoutParams()).onViewAttached(mInLayout); 683 } 684 return v; 685 } 686 687 final int getOpticalLeft(View v) { 688 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 689 } 690 691 final int getOpticalRight(View v) { 692 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 693 } 694 695 final int getOpticalTop(View v) { 696 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 697 } 698 699 final int getOpticalBottom(View v) { 700 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 701 } 702 703 private int getViewMin(View v) { 704 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 705 } 706 707 private int getViewMax(View v) { 708 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 709 } 710 711 private int getViewCenter(View view) { 712 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 713 } 714 715 private int getViewCenterSecondary(View view) { 716 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 717 } 718 719 private int getViewCenterX(View v) { 720 LayoutParams p = (LayoutParams) v.getLayoutParams(); 721 return p.getOpticalLeft(v) + p.getAlignX(); 722 } 723 724 private int getViewCenterY(View v) { 725 LayoutParams p = (LayoutParams) v.getLayoutParams(); 726 return p.getOpticalTop(v) + p.getAlignY(); 727 } 728 729 private void setViewLayoutForward(View v, boolean layoutForward) { 730 LayoutParams p = (LayoutParams) v.getLayoutParams(); 731 p.mLayoutForward = layoutForward; 732 } 733 734 private boolean getIsViewLayoutForward(View v) { 735 return ((LayoutParams) v.getLayoutParams()).mLayoutForward; 736 } 737 738 /** 739 * Re-initialize data structures for a data change or handling invisible 740 * selection. The method tries its best to preserve position information so 741 * that staggered grid looks same before and after re-initialize. 742 * @param focusPosition The initial focusPosition that we would like to 743 * focus on. 744 * @return Actual position that can be focused on. 745 */ 746 private int init(RecyclerView.Adapter adapter, RecyclerView.Recycler recycler, 747 int focusPosition) { 748 749 final int newItemCount = adapter.getItemCount(); 750 751 if (focusPosition == NO_POSITION && newItemCount > 0) { 752 // if focus position is never set before, initialize it to 0 753 focusPosition = 0; 754 } 755 // If adapter has changed then caches are invalid; otherwise, 756 // we try to maintain each row's position if number of rows keeps the same 757 // and existing mGrid contains the focusPosition. 758 if (mRows != null && mNumRows == mRows.length && 759 mGrid != null && mGrid.getSize() > 0 && focusPosition >= 0 && 760 focusPosition >= mGrid.getFirstIndex() && 761 focusPosition <= mGrid.getLastIndex()) { 762 // strip mGrid to a subset (like a column) that contains focusPosition 763 mGrid.stripDownTo(focusPosition); 764 // make sure that remaining items do not exceed new adapter size 765 int firstIndex = mGrid.getFirstIndex(); 766 int lastIndex = mGrid.getLastIndex(); 767 if (DEBUG) { 768 Log .v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " + lastIndex); 769 } 770 for (int i = lastIndex; i >=firstIndex; i--) { 771 if (i >= newItemCount) { 772 mGrid.removeLast(); 773 } 774 } 775 if (mGrid.getSize() == 0) { 776 focusPosition = newItemCount - 1; 777 // initialize row start locations 778 for (int i = 0; i < mNumRows; i++) { 779 mRows[i].low = 0; 780 mRows[i].high = 0; 781 } 782 if (DEBUG) Log.v(getTag(), "mGrid zero size"); 783 } else { 784 // initialize row start locations 785 for (int i = 0; i < mNumRows; i++) { 786 mRows[i].low = Integer.MAX_VALUE; 787 mRows[i].high = Integer.MIN_VALUE; 788 } 789 firstIndex = mGrid.getFirstIndex(); 790 lastIndex = mGrid.getLastIndex(); 791 if (focusPosition > lastIndex) { 792 focusPosition = mGrid.getLastIndex(); 793 } 794 if (DEBUG) { 795 Log.v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " 796 + lastIndex + " focusPosition " + focusPosition); 797 } 798 // fill rows with minimal view positions of the subset 799 for (int i = firstIndex; i <= lastIndex; i++) { 800 View v = getViewByPosition(i); 801 if (v == null) { 802 continue; 803 } 804 int row = mGrid.getLocation(i).row; 805 int low = getViewMin(v) + mScrollOffsetPrimary; 806 if (low < mRows[row].low) { 807 mRows[row].low = mRows[row].high = low; 808 } 809 } 810 // fill other rows that does not include the subset using first item 811 int firstItemRowPosition = mRows[mGrid.getLocation(firstIndex).row].low; 812 if (firstItemRowPosition == Integer.MAX_VALUE) { 813 firstItemRowPosition = 0; 814 } 815 for (int i = 0; i < mNumRows; i++) { 816 if (mRows[i].low == Integer.MAX_VALUE) { 817 mRows[i].low = mRows[i].high = firstItemRowPosition; 818 } 819 } 820 } 821 822 // Same adapter, we can reuse any attached views 823 detachAndScrapAttachedViews(recycler); 824 825 } else { 826 // otherwise recreate data structure 827 mRows = new StaggeredGrid.Row[mNumRows]; 828 mRowSizeSecondary = new int[mNumRows]; 829 830 for (int i = 0; i < mNumRows; i++) { 831 mRows[i] = new StaggeredGrid.Row(); 832 } 833 mGrid = new StaggeredGridDefault(); 834 if (newItemCount == 0) { 835 focusPosition = NO_POSITION; 836 } else if (focusPosition >= newItemCount) { 837 focusPosition = newItemCount - 1; 838 } 839 840 // Adapter may have changed so remove all attached views permanently 841 removeAllViews(); 842 843 mScrollOffsetPrimary = 0; 844 mScrollOffsetSecondary = 0; 845 mWindowAlignment.reset(); 846 } 847 848 mAdapter = adapter; 849 mRecycler = recycler; 850 mGrid.setProvider(mGridProvider); 851 // mGrid share the same Row array information 852 mGrid.setRows(mRows); 853 mFirstVisiblePos = mLastVisiblePos = NO_POSITION; 854 855 initScrollController(); 856 updateScrollSecondAxis(); 857 858 return focusPosition; 859 } 860 861 private int getRowSizeSecondary(int rowIndex) { 862 if (mFixedRowSizeSecondary != 0) { 863 return mFixedRowSizeSecondary; 864 } 865 if (mRowSizeSecondary == null) { 866 return 0; 867 } 868 return mRowSizeSecondary[rowIndex]; 869 } 870 871 private int getRowStartSecondary(int rowIndex) { 872 int start = 0; 873 for (int i = 0; i < rowIndex; i++) { 874 start += getRowSizeSecondary(i) + mMarginSecondary; 875 } 876 return start; 877 } 878 879 private int getSizeSecondary() { 880 return getRowStartSecondary(mNumRows - 1) + getRowSizeSecondary(mNumRows - 1); 881 } 882 883 private boolean processRowSizeSecondary(boolean measure) { 884 if (mFixedRowSizeSecondary != 0) { 885 return false; 886 } 887 888 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 889 boolean changed = false; 890 891 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 892 int rowSize = 0; 893 894 final int rowItemCount = rows[rowIndex].size(); 895 if (DEBUG) Log.v(getTag(), "processRowSizeSecondary row " + rowIndex + 896 " rowItemCount " + rowItemCount); 897 898 for (int i = 0; i < rowItemCount; i++) { 899 final int position = rows[rowIndex].get(i); 900 final View view = getViewByPosition(position); 901 if (measure && view.isLayoutRequested()) { 902 measureChild(view, rowIndex); 903 } 904 // If this view isn't visible, we ignore it. 905 if (getOpticalRight(view) < 0 || getOpticalLeft(view) > getWidth() || 906 getOpticalBottom(view) < 0 || getOpticalTop(view) > getHeight()) { 907 continue; 908 } 909 final int secondarySize = mOrientation == HORIZONTAL ? 910 view.getMeasuredHeight() : view.getMeasuredWidth(); 911 if (secondarySize > rowSize) { 912 rowSize = secondarySize; 913 } 914 } 915 if (DEBUG) Log.v(getTag(), "row " + rowIndex + " rowItemCount " + rowItemCount + 916 " rowSize " + rowSize); 917 918 if (mRowSizeSecondary[rowIndex] != rowSize) { 919 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 920 ", " + rowSize); 921 922 mRowSizeSecondary[rowIndex] = rowSize; 923 changed = true; 924 } 925 } 926 927 return changed; 928 } 929 930 /** 931 * Checks if we need to update row secondary sizes. 932 */ 933 private void updateRowSecondarySizeRefresh() { 934 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 935 if (mRowSecondarySizeRefresh) { 936 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 937 forceRequestLayout(); 938 } 939 } 940 941 private void forceRequestLayout() { 942 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 943 // RecyclerView prevents us from requesting layout in many cases 944 // (during layout, during scroll, etc.) 945 // For secondary row size wrap_content support we currently need a 946 // second layout pass to update the measured size after having measured 947 // and added child views in layoutChildren. 948 // Force the second layout by posting a delayed runnable. 949 // TODO: investigate allowing a second layout pass, 950 // or move child add/measure logic to the measure phase. 951 mBaseGridView.getHandler().post(new Runnable() { 952 @Override 953 public void run() { 954 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 955 requestLayout(); 956 } 957 }); 958 } 959 960 @Override 961 public void onMeasure(int widthSpec, int heightSpec) { 962 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 963 int measuredSizeSecondary; 964 if (mOrientation == HORIZONTAL) { 965 sizePrimary = MeasureSpec.getSize(widthSpec); 966 sizeSecondary = MeasureSpec.getSize(heightSpec); 967 modeSecondary = MeasureSpec.getMode(heightSpec); 968 paddingSecondary = getPaddingTop() + getPaddingBottom(); 969 } else { 970 sizeSecondary = MeasureSpec.getSize(widthSpec); 971 sizePrimary = MeasureSpec.getSize(heightSpec); 972 modeSecondary = MeasureSpec.getMode(widthSpec); 973 paddingSecondary = getPaddingLeft() + getPaddingRight(); 974 } 975 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 976 " heightSpec " + Integer.toHexString(heightSpec) + 977 " modeSecondary " + Integer.toHexString(modeSecondary) + 978 " sizeSecondary " + sizeSecondary + " " + this); 979 980 mMaxSizeSecondary = sizeSecondary; 981 982 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 983 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 984 mFixedRowSizeSecondary = 0; 985 986 // Measure all current children and update cached row heights 987 if (mGrid != null) { 988 processRowSizeSecondary(true); 989 } 990 991 switch (modeSecondary) { 992 case MeasureSpec.UNSPECIFIED: 993 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 994 break; 995 case MeasureSpec.AT_MOST: 996 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 997 mMaxSizeSecondary); 998 break; 999 case MeasureSpec.EXACTLY: 1000 measuredSizeSecondary = mMaxSizeSecondary; 1001 break; 1002 default: 1003 throw new IllegalStateException("wrong spec"); 1004 } 1005 1006 } else { 1007 switch (modeSecondary) { 1008 case MeasureSpec.UNSPECIFIED: 1009 if (mRowSizeSecondaryRequested == 0) { 1010 if (mOrientation == HORIZONTAL) { 1011 throw new IllegalStateException("Must specify rowHeight or view height"); 1012 } else { 1013 throw new IllegalStateException("Must specify columnWidth or view width"); 1014 } 1015 } 1016 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1017 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 1018 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1019 * (mNumRows - 1) + paddingSecondary; 1020 break; 1021 case MeasureSpec.AT_MOST: 1022 case MeasureSpec.EXACTLY: 1023 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 1024 mNumRows = 1; 1025 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 1026 } else if (mNumRowsRequested == 0) { 1027 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1028 mNumRows = (sizeSecondary + mMarginSecondary) 1029 / (mRowSizeSecondaryRequested + mMarginSecondary); 1030 } else if (mRowSizeSecondaryRequested == 0) { 1031 mNumRows = mNumRowsRequested; 1032 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 1033 * (mNumRows - 1)) / mNumRows; 1034 } else { 1035 mNumRows = mNumRowsRequested; 1036 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1037 } 1038 measuredSizeSecondary = sizeSecondary; 1039 if (modeSecondary == MeasureSpec.AT_MOST) { 1040 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1041 * (mNumRows - 1) + paddingSecondary; 1042 if (childrenSize < measuredSizeSecondary) { 1043 measuredSizeSecondary = childrenSize; 1044 } 1045 } 1046 break; 1047 default: 1048 throw new IllegalStateException("wrong spec"); 1049 } 1050 } 1051 if (mOrientation == HORIZONTAL) { 1052 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1053 } else { 1054 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1055 } 1056 if (DEBUG) { 1057 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1058 " measuredSizeSecondary " + measuredSizeSecondary + 1059 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1060 " mNumRows " + mNumRows); 1061 } 1062 } 1063 1064 private void measureChild(View child, int rowIndex) { 1065 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1066 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1067 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1068 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1069 int widthSpec, heightSpec; 1070 1071 if (mOrientation == HORIZONTAL) { 1072 widthSpec = ViewGroup.getChildMeasureSpec( 1073 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1074 0, lp.width); 1075 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1076 } else { 1077 heightSpec = ViewGroup.getChildMeasureSpec( 1078 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1079 0, lp.height); 1080 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1081 } 1082 1083 child.measure(widthSpec, heightSpec); 1084 1085 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1086 " widthSpec " + Integer.toHexString(widthSpec) + 1087 " heightSpec " + Integer.toHexString(heightSpec) + 1088 " measuredWidth " + child.getMeasuredWidth() + 1089 " measuredHeight " + child.getMeasuredHeight()); 1090 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1091 } 1092 1093 private StaggeredGrid.Provider mGridProvider = new StaggeredGrid.Provider() { 1094 1095 @Override 1096 public int getCount() { 1097 return mAdapter.getItemCount(); 1098 } 1099 1100 @Override 1101 public void createItem(int index, int rowIndex, boolean append) { 1102 View v = getViewForPosition(index); 1103 if (mFirstVisiblePos >= 0) { 1104 // when StaggeredGrid append or prepend item, we must guarantee 1105 // that sibling item has created views already. 1106 if (append && index != mLastVisiblePos + 1) { 1107 throw new RuntimeException(); 1108 } else if (!append && index != mFirstVisiblePos - 1) { 1109 throw new RuntimeException(); 1110 } 1111 } 1112 1113 if (append) { 1114 addView(v); 1115 } else { 1116 addView(v, 0); 1117 } 1118 1119 measureChild(v, rowIndex); 1120 1121 int length = mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1122 int start, end; 1123 if (append) { 1124 start = mRows[rowIndex].high; 1125 if (start != mRows[rowIndex].low) { 1126 // if there are existing item in the row, add margin between 1127 start += mMarginPrimary; 1128 } else { 1129 final int lastRow = mRows.length - 1; 1130 if (lastRow != rowIndex && mRows[lastRow].high != mRows[lastRow].low) { 1131 // if there are existing item in the last row, insert 1132 // the new item after the last item of last row. 1133 start = mRows[lastRow].high + mMarginPrimary; 1134 } 1135 } 1136 end = start + length; 1137 mRows[rowIndex].high = end; 1138 } else { 1139 end = mRows[rowIndex].low; 1140 if (end != mRows[rowIndex].high) { 1141 end -= mMarginPrimary; 1142 } else if (0 != rowIndex && mRows[0].high != mRows[0].low) { 1143 // if there are existing item in the first row, insert 1144 // the new item before the first item of first row. 1145 end = mRows[0].low - mMarginPrimary; 1146 } 1147 start = end - length; 1148 mRows[rowIndex].low = start; 1149 } 1150 if (mFirstVisiblePos < 0) { 1151 mFirstVisiblePos = mLastVisiblePos = index; 1152 } else { 1153 if (append) { 1154 mLastVisiblePos++; 1155 } else { 1156 mFirstVisiblePos--; 1157 } 1158 } 1159 if (DEBUG) Log.v(getTag(), "start " + start + " end " + end); 1160 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1161 layoutChild(rowIndex, v, start - mScrollOffsetPrimary, end - mScrollOffsetPrimary, 1162 startSecondary); 1163 if (DEBUG) { 1164 Log.d(getTag(), "addView " + index + " " + v); 1165 } 1166 updateScrollMin(); 1167 updateScrollMax(); 1168 1169 setViewLayoutForward(v, append); 1170 } 1171 }; 1172 1173 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1174 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1175 : v.getMeasuredWidth(); 1176 if (mFixedRowSizeSecondary > 0) { 1177 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1178 } 1179 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1180 final int horizontalGravity = mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1181 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1182 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1183 // do nothing 1184 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1185 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1186 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1187 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1188 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1189 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1190 } 1191 int left, top, right, bottom; 1192 if (mOrientation == HORIZONTAL) { 1193 left = start; 1194 top = startSecondary; 1195 right = end; 1196 bottom = startSecondary + sizeSecondary; 1197 } else { 1198 top = start; 1199 left = startSecondary; 1200 bottom = end; 1201 right = startSecondary + sizeSecondary; 1202 } 1203 v.layout(left, top, right, bottom); 1204 updateChildOpticalInsets(v, left, top, right, bottom); 1205 updateChildAlignments(v); 1206 } 1207 1208 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1209 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1210 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1211 v.getRight() - right, v.getBottom() - bottom); 1212 } 1213 1214 private void updateChildAlignments(View v) { 1215 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1216 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1217 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1218 } 1219 1220 private void updateChildAlignments() { 1221 for (int i = 0, c = getChildCount(); i < c; i++) { 1222 updateChildAlignments(getChildAt(i)); 1223 } 1224 } 1225 1226 private boolean needsAppendVisibleItem() { 1227 if (mLastVisiblePos < mFocusPosition) { 1228 return true; 1229 } 1230 int right = mScrollOffsetPrimary + mSizePrimary; 1231 for (int i = 0; i < mNumRows; i++) { 1232 if (mRows[i].low == mRows[i].high) { 1233 if (mRows[i].high < right) { 1234 return true; 1235 } 1236 } else if (mRows[i].high < right - mMarginPrimary) { 1237 return true; 1238 } 1239 } 1240 return false; 1241 } 1242 1243 private boolean needsPrependVisibleItem() { 1244 if (mFirstVisiblePos > mFocusPosition) { 1245 return true; 1246 } 1247 for (int i = 0; i < mNumRows; i++) { 1248 if (mRows[i].low == mRows[i].high) { 1249 if (mRows[i].low > mScrollOffsetPrimary) { 1250 return true; 1251 } 1252 } else if (mRows[i].low - mMarginPrimary > mScrollOffsetPrimary) { 1253 return true; 1254 } 1255 } 1256 return false; 1257 } 1258 1259 // Append one column if possible and return true if reach end. 1260 private boolean appendOneVisibleItem() { 1261 while (true) { 1262 if (mLastVisiblePos != NO_POSITION && mLastVisiblePos < mAdapter.getItemCount() -1 && 1263 mLastVisiblePos < mGrid.getLastIndex()) { 1264 // append invisible view of saved location till last row 1265 final int index = mLastVisiblePos + 1; 1266 final int row = mGrid.getLocation(index).row; 1267 mGridProvider.createItem(index, row, true); 1268 if (row == mNumRows - 1) { 1269 return false; 1270 } 1271 } else if ((mLastVisiblePos == NO_POSITION && mAdapter.getItemCount() > 0) || 1272 (mLastVisiblePos != NO_POSITION && 1273 mLastVisiblePos < mAdapter.getItemCount() - 1)) { 1274 mGrid.appendItems(mScrollOffsetPrimary + mSizePrimary); 1275 return false; 1276 } else { 1277 return true; 1278 } 1279 } 1280 } 1281 1282 private void appendVisibleItems() { 1283 while (needsAppendVisibleItem()) { 1284 if (appendOneVisibleItem()) { 1285 break; 1286 } 1287 } 1288 } 1289 1290 // Prepend one column if possible and return true if reach end. 1291 private boolean prependOneVisibleItem() { 1292 while (true) { 1293 if (mFirstVisiblePos > 0) { 1294 if (mFirstVisiblePos > mGrid.getFirstIndex()) { 1295 // prepend invisible view of saved location till first row 1296 final int index = mFirstVisiblePos - 1; 1297 final int row = mGrid.getLocation(index).row; 1298 mGridProvider.createItem(index, row, false); 1299 if (row == 0) { 1300 return false; 1301 } 1302 } else { 1303 mGrid.prependItems(mScrollOffsetPrimary); 1304 return false; 1305 } 1306 } else { 1307 return true; 1308 } 1309 } 1310 } 1311 1312 private void prependVisibleItems() { 1313 while (needsPrependVisibleItem()) { 1314 if (prependOneVisibleItem()) { 1315 break; 1316 } 1317 } 1318 } 1319 1320 private void removeChildAt(int position) { 1321 View v = getViewByPosition(position); 1322 if (v != null) { 1323 if (DEBUG) { 1324 Log.d(getTag(), "removeAndRecycleViewAt " + position); 1325 } 1326 ((LayoutParams) v.getLayoutParams()).onViewDetached(); 1327 removeAndRecycleViewAt(getIndexByPosition(position), mRecycler); 1328 } 1329 } 1330 1331 private void removeInvisibleViewsAtEnd() { 1332 if (!mPruneChild) { 1333 return; 1334 } 1335 boolean update = false; 1336 while(mLastVisiblePos > mFirstVisiblePos && mLastVisiblePos > mFocusPosition) { 1337 View view = getViewByPosition(mLastVisiblePos); 1338 if (getViewMin(view) > mSizePrimary) { 1339 removeChildAt(mLastVisiblePos); 1340 mLastVisiblePos--; 1341 update = true; 1342 } else { 1343 break; 1344 } 1345 } 1346 if (update) { 1347 updateRowsMinMax(); 1348 } 1349 } 1350 1351 private void removeInvisibleViewsAtFront() { 1352 if (!mPruneChild) { 1353 return; 1354 } 1355 boolean update = false; 1356 while(mLastVisiblePos > mFirstVisiblePos && mFirstVisiblePos < mFocusPosition) { 1357 View view = getViewByPosition(mFirstVisiblePos); 1358 if (getViewMax(view) < 0) { 1359 removeChildAt(mFirstVisiblePos); 1360 mFirstVisiblePos++; 1361 update = true; 1362 } else { 1363 break; 1364 } 1365 } 1366 if (update) { 1367 updateRowsMinMax(); 1368 } 1369 } 1370 1371 private void updateRowsMinMax() { 1372 if (mFirstVisiblePos < 0) { 1373 return; 1374 } 1375 for (int i = 0; i < mNumRows; i++) { 1376 mRows[i].low = Integer.MAX_VALUE; 1377 mRows[i].high = Integer.MIN_VALUE; 1378 } 1379 for (int i = mFirstVisiblePos; i <= mLastVisiblePos; i++) { 1380 View view = getViewByPosition(i); 1381 int row = mGrid.getLocation(i).row; 1382 int low = getViewMin(view) + mScrollOffsetPrimary; 1383 if (low < mRows[row].low) { 1384 mRows[row].low = low; 1385 } 1386 int high = getViewMax(view) + mScrollOffsetPrimary; 1387 if (high > mRows[row].high) { 1388 mRows[row].high = high; 1389 } 1390 } 1391 } 1392 1393 // Fast layout when there is no structure change, adapter change, etc. 1394 protected void fastRelayout() { 1395 initScrollController(); 1396 1397 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 1398 1399 // relayout and repositioning views on each row 1400 for (int i = 0; i < mNumRows; i++) { 1401 List<Integer> row = rows[i]; 1402 final int startSecondary = getRowStartSecondary(i) - mScrollOffsetSecondary; 1403 for (int j = 0, size = row.size(); j < size; j++) { 1404 final int position = row.get(j); 1405 final View view = getViewByPosition(position); 1406 final boolean layoutForward = getIsViewLayoutForward(view); 1407 int primaryDelta, start, end; 1408 1409 if (mOrientation == HORIZONTAL) { 1410 final int primarySize = view.getMeasuredWidth(); 1411 if (view.isLayoutRequested()) { 1412 measureChild(view, i); 1413 } 1414 if (layoutForward) { 1415 start = getViewMin(view); 1416 end = start + view.getMeasuredWidth(); 1417 primaryDelta = view.getMeasuredWidth() - primarySize; 1418 if (primaryDelta != 0) { 1419 for (int k = j + 1; k < size; k++) { 1420 getViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1421 } 1422 } 1423 } else { 1424 end = getViewMax(view); 1425 start = end - view.getMeasuredWidth(); 1426 primaryDelta = primarySize - view.getMeasuredWidth(); 1427 if (primaryDelta != 0) { 1428 for (int k = 0; k < j; k++) { 1429 getViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1430 } 1431 } 1432 } 1433 } else { 1434 final int primarySize = view.getMeasuredHeight(); 1435 if (view.isLayoutRequested()) { 1436 measureChild(view, i); 1437 } 1438 if (layoutForward) { 1439 start = getViewMin(view); 1440 end = start + view.getMeasuredHeight(); 1441 primaryDelta = view.getMeasuredHeight() - primarySize; 1442 if (primaryDelta != 0) { 1443 for (int k = j + 1; k < size; k++) { 1444 getViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1445 } 1446 } 1447 } else { 1448 end = getViewMax(view); 1449 start = end - view.getMeasuredHeight(); 1450 primaryDelta = primarySize - view.getMeasuredHeight(); 1451 if (primaryDelta != 0) { 1452 for (int k = 0; k < j; k++) { 1453 getViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1454 } 1455 } 1456 } 1457 } 1458 layoutChild(i, view, start, end, startSecondary); 1459 } 1460 } 1461 1462 updateRowsMinMax(); 1463 appendVisibleItems(); 1464 prependVisibleItems(); 1465 1466 updateRowsMinMax(); 1467 updateScrollMin(); 1468 updateScrollMax(); 1469 updateScrollSecondAxis(); 1470 1471 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1472 View focusView = getViewByPosition(mFocusPosition == NO_POSITION ? 0 : mFocusPosition); 1473 scrollToView(focusView, false); 1474 } 1475 } 1476 1477 // Lays out items based on the current scroll position 1478 @Override 1479 public void onLayoutChildren(RecyclerView.Adapter adapter, RecyclerView.Recycler recycler, 1480 boolean structureChanged, RecyclerView.State state) { 1481 if (DEBUG) { 1482 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1483 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1484 + " structureChanged " + structureChanged 1485 + " mForceFullLayout " + mForceFullLayout); 1486 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1487 } 1488 1489 if (mNumRows == 0) { 1490 // haven't done measure yet 1491 return; 1492 } 1493 final int itemCount = adapter.getItemCount(); 1494 if (itemCount < 0) { 1495 return; 1496 } 1497 1498 if (!mLayoutEnabled) { 1499 discardLayoutInfo(); 1500 removeAllViews(); 1501 return; 1502 } 1503 mInLayout = true; 1504 1505 attemptRecordChildLayout(); 1506 // Track the old focus view so we can adjust our system scroll position 1507 // so that any scroll animations happening now will remain valid. 1508 int delta = 0, deltaSecondary = 0; 1509 if (mFocusPosition != NO_POSITION 1510 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1511 View focusView = getViewByPosition(mFocusPosition); 1512 if (focusView != null) { 1513 delta = mWindowAlignment.mainAxis().getSystemScrollPos( 1514 getViewCenter(focusView) + mScrollOffsetPrimary) - mScrollOffsetPrimary; 1515 deltaSecondary = 1516 mWindowAlignment.secondAxis().getSystemScrollPos( 1517 getViewCenterSecondary(focusView) + mScrollOffsetSecondary) 1518 - mScrollOffsetSecondary; 1519 } 1520 } 1521 1522 final boolean hasDoneFirstLayout = hasDoneFirstLayout(); 1523 if (!structureChanged && !mForceFullLayout && hasDoneFirstLayout) { 1524 fastRelayout(); 1525 } else { 1526 boolean hadFocus = mBaseGridView.hasFocus(); 1527 1528 int newFocusPosition = init(adapter, recycler, mFocusPosition); 1529 if (DEBUG) { 1530 Log.v(getTag(), "mFocusPosition " + mFocusPosition + " newFocusPosition " 1531 + newFocusPosition); 1532 } 1533 1534 // depending on result of init(), either recreating everything 1535 // or try to reuse the row start positions near mFocusPosition 1536 if (mGrid.getSize() == 0) { 1537 // this is a fresh creating all items, starting from 1538 // mFocusPosition with a estimated row index. 1539 mGrid.setStart(newFocusPosition, StaggeredGrid.START_DEFAULT); 1540 1541 // Can't track the old focus view 1542 delta = deltaSecondary = 0; 1543 1544 } else { 1545 // mGrid remembers Locations for the column that 1546 // contains mFocusePosition and also mRows remembers start 1547 // positions of each row. 1548 // Manually re-create child views for that column 1549 int firstIndex = mGrid.getFirstIndex(); 1550 int lastIndex = mGrid.getLastIndex(); 1551 for (int i = firstIndex; i <= lastIndex; i++) { 1552 mGridProvider.createItem(i, mGrid.getLocation(i).row, true); 1553 } 1554 } 1555 // add visible views at end until reach the end of window 1556 appendVisibleItems(); 1557 // add visible views at front until reach the start of window 1558 prependVisibleItems(); 1559 // multiple rounds: scrollToView of first round may drag first/last child into 1560 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1561 int oldFirstVisible; 1562 int oldLastVisible; 1563 do { 1564 oldFirstVisible = mFirstVisiblePos; 1565 oldLastVisible = mLastVisiblePos; 1566 View focusView = getViewByPosition(newFocusPosition); 1567 // we need force to initialize the child view's position 1568 scrollToView(focusView, false); 1569 if (focusView != null && hadFocus) { 1570 focusView.requestFocus(); 1571 } 1572 appendVisibleItems(); 1573 prependVisibleItems(); 1574 removeInvisibleViewsAtFront(); 1575 removeInvisibleViewsAtEnd(); 1576 } while (mFirstVisiblePos != oldFirstVisible || mLastVisiblePos != oldLastVisible); 1577 } 1578 mForceFullLayout = false; 1579 1580 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1581 scrollDirectionPrimary(-delta); 1582 scrollDirectionSecondary(-deltaSecondary); 1583 } 1584 appendVisibleItems(); 1585 prependVisibleItems(); 1586 removeInvisibleViewsAtFront(); 1587 removeInvisibleViewsAtEnd(); 1588 1589 if (DEBUG) { 1590 StringWriter sw = new StringWriter(); 1591 PrintWriter pw = new PrintWriter(sw); 1592 mGrid.debugPrint(pw); 1593 Log.d(getTag(), sw.toString()); 1594 } 1595 1596 removeAndRecycleScrap(recycler); 1597 attemptAnimateLayoutChild(); 1598 1599 if (mRowSecondarySizeRefresh) { 1600 mRowSecondarySizeRefresh = false; 1601 } else { 1602 updateRowSecondarySizeRefresh(); 1603 } 1604 1605 if (!hasDoneFirstLayout) { 1606 dispatchChildSelected(); 1607 } 1608 mInLayout = false; 1609 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1610 } 1611 1612 private void offsetChildrenSecondary(int increment) { 1613 final int childCount = getChildCount(); 1614 if (mOrientation == HORIZONTAL) { 1615 for (int i = 0; i < childCount; i++) { 1616 getChildAt(i).offsetTopAndBottom(increment); 1617 } 1618 } else { 1619 for (int i = 0; i < childCount; i++) { 1620 getChildAt(i).offsetLeftAndRight(increment); 1621 } 1622 } 1623 mScrollOffsetSecondary -= increment; 1624 } 1625 1626 private void offsetChildrenPrimary(int increment) { 1627 final int childCount = getChildCount(); 1628 if (mOrientation == VERTICAL) { 1629 for (int i = 0; i < childCount; i++) { 1630 getChildAt(i).offsetTopAndBottom(increment); 1631 } 1632 } else { 1633 for (int i = 0; i < childCount; i++) { 1634 getChildAt(i).offsetLeftAndRight(increment); 1635 } 1636 } 1637 mScrollOffsetPrimary -= increment; 1638 } 1639 1640 @Override 1641 public int scrollHorizontallyBy(int dx, Adapter adapter, Recycler recycler, 1642 RecyclerView.State state) { 1643 if (DEBUG) Log.v(TAG, "scrollHorizontallyBy " + dx); 1644 1645 if (mOrientation == HORIZONTAL) { 1646 return scrollDirectionPrimary(dx); 1647 } else { 1648 return scrollDirectionSecondary(dx); 1649 } 1650 } 1651 1652 @Override 1653 public int scrollVerticallyBy(int dy, Adapter adapter, Recycler recycler, 1654 RecyclerView.State state) { 1655 if (DEBUG) Log.v(TAG, "scrollVerticallyBy " + dy); 1656 if (mOrientation == VERTICAL) { 1657 return scrollDirectionPrimary(dy); 1658 } else { 1659 return scrollDirectionSecondary(dy); 1660 } 1661 } 1662 1663 // scroll in main direction may add/prune views 1664 private int scrollDirectionPrimary(int da) { 1665 offsetChildrenPrimary(-da); 1666 if (mInLayout) { 1667 return da; 1668 } 1669 1670 int childCount = getChildCount(); 1671 boolean updated; 1672 1673 if (da > 0) { 1674 appendVisibleItems(); 1675 } else if (da < 0) { 1676 prependVisibleItems(); 1677 } 1678 updated = getChildCount() > childCount; 1679 childCount = getChildCount(); 1680 1681 if (da > 0) { 1682 removeInvisibleViewsAtFront(); 1683 } else if (da < 0) { 1684 removeInvisibleViewsAtEnd(); 1685 } 1686 updated |= getChildCount() < childCount; 1687 1688 if (updated) { 1689 updateRowSecondarySizeRefresh(); 1690 } 1691 1692 mBaseGridView.invalidate(); 1693 return da; 1694 } 1695 1696 // scroll in second direction will not add/prune views 1697 private int scrollDirectionSecondary(int dy) { 1698 offsetChildrenSecondary(-dy); 1699 mBaseGridView.invalidate(); 1700 return dy; 1701 } 1702 1703 private void updateScrollMax() { 1704 if (mLastVisiblePos >= 0 && mLastVisiblePos == mAdapter.getItemCount() - 1) { 1705 int maxEdge = Integer.MIN_VALUE; 1706 for (int i = 0; i < mRows.length; i++) { 1707 if (mRows[i].high > maxEdge) { 1708 maxEdge = mRows[i].high; 1709 } 1710 } 1711 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1712 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge); 1713 } 1714 } 1715 1716 private void updateScrollMin() { 1717 if (mFirstVisiblePos == 0) { 1718 int minEdge = Integer.MAX_VALUE; 1719 for (int i = 0; i < mRows.length; i++) { 1720 if (mRows[i].low < minEdge) { 1721 minEdge = mRows[i].low; 1722 } 1723 } 1724 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1725 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge); 1726 } 1727 } 1728 1729 private void updateScrollSecondAxis() { 1730 mWindowAlignment.secondAxis().setMinEdge(0); 1731 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1732 } 1733 1734 private void initScrollController() { 1735 mWindowAlignment.horizontal.setSize(getWidth()); 1736 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1737 mWindowAlignment.vertical.setSize(getHeight()); 1738 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1739 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1740 mWindowAlignment.mainAxis().invalidateScrollMin(); 1741 mWindowAlignment.mainAxis().invalidateScrollMax(); 1742 1743 if (DEBUG) { 1744 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1745 + " mWindowAlignment " + mWindowAlignment); 1746 } 1747 } 1748 1749 public void setSelection(RecyclerView parent, int position) { 1750 setSelection(parent, position, false); 1751 } 1752 1753 public void setSelectionSmooth(RecyclerView parent, int position) { 1754 setSelection(parent, position, true); 1755 } 1756 1757 public int getSelection() { 1758 return mFocusPosition; 1759 } 1760 1761 public void setSelection(RecyclerView parent, int position, boolean smooth) { 1762 if (mFocusPosition == position) { 1763 return; 1764 } 1765 View view = getViewByPosition(position); 1766 if (view != null) { 1767 scrollToView(view, smooth); 1768 } else { 1769 boolean right = position > mFocusPosition; 1770 mFocusPosition = position; 1771 if (!mLayoutEnabled) { 1772 return; 1773 } 1774 if (smooth) { 1775 if (!hasDoneFirstLayout()) { 1776 Log.w(getTag(), "setSelectionSmooth should " + 1777 "not be called before first layout pass"); 1778 return; 1779 } 1780 if (right) { 1781 appendVisibleItems(); 1782 } else { 1783 prependVisibleItems(); 1784 } 1785 scrollToView(getViewByPosition(position), smooth); 1786 } else { 1787 mForceFullLayout = true; 1788 parent.requestLayout(); 1789 } 1790 } 1791 } 1792 1793 @Override 1794 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 1795 boolean needsLayout = false; 1796 if (itemCount != 0) { 1797 if (mFirstVisiblePos < 0) { 1798 needsLayout = true; 1799 } else if (!(positionStart > mLastVisiblePos + 1 || 1800 positionStart + itemCount < mFirstVisiblePos - 1)) { 1801 needsLayout = true; 1802 } 1803 } 1804 if (needsLayout) { 1805 recyclerView.requestLayout(); 1806 } 1807 } 1808 1809 @Override 1810 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 1811 if (mFocusSearchDisabled) { 1812 return true; 1813 } 1814 if (!mInLayout) { 1815 scrollToView(child, true); 1816 } 1817 return true; 1818 } 1819 1820 @Override 1821 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 1822 boolean immediate) { 1823 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 1824 return false; 1825 } 1826 1827 int getScrollOffsetX() { 1828 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 1829 } 1830 1831 int getScrollOffsetY() { 1832 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 1833 } 1834 1835 public void getViewSelectedOffsets(View view, int[] offsets) { 1836 int scrollOffsetX = getScrollOffsetX(); 1837 int scrollOffsetY = getScrollOffsetY(); 1838 int viewCenterX = scrollOffsetX + getViewCenterX(view); 1839 int viewCenterY = scrollOffsetY + getViewCenterY(view); 1840 offsets[0] = mWindowAlignment.horizontal.getSystemScrollPos(viewCenterX) - scrollOffsetX; 1841 offsets[1] = mWindowAlignment.vertical.getSystemScrollPos(viewCenterY) - scrollOffsetY; 1842 } 1843 1844 /** 1845 * Scroll to a given child view and change mFocusPosition. 1846 */ 1847 private void scrollToView(View view, boolean smooth) { 1848 int newFocusPosition = getPositionByView(view); 1849 if (mInLayout || newFocusPosition != mFocusPosition) { 1850 mFocusPosition = newFocusPosition; 1851 dispatchChildSelected(); 1852 } 1853 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 1854 mBaseGridView.invalidate(); 1855 } 1856 if (view == null) { 1857 return; 1858 } 1859 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 1860 // transfer focus to the child if it does not have focus yet (e.g. triggered 1861 // by setSelection()) 1862 view.requestFocus(); 1863 } 1864 switch (mFocusScrollStrategy) { 1865 case BaseGridView.FOCUS_SCROLL_ALIGNED: 1866 default: 1867 scrollToAlignedPosition(view, smooth); 1868 break; 1869 case BaseGridView.FOCUS_SCROLL_ITEM: 1870 case BaseGridView.FOCUS_SCROLL_PAGE: 1871 scrollItemOrPage(view, smooth); 1872 break; 1873 } 1874 } 1875 1876 private void scrollItemOrPage(View view, boolean smooth) { 1877 int pos = getPositionByView(view); 1878 int viewMin = getViewMin(view); 1879 int viewMax = getViewMax(view); 1880 // we either align "firstView" to left/top padding edge 1881 // or align "lastView" to right/bottom padding edge 1882 View firstView = null; 1883 View lastView = null; 1884 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 1885 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 1886 final int row = mGrid.getLocation(pos).row; 1887 if (viewMin < paddingLow) { 1888 // view enters low padding area: 1889 firstView = view; 1890 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1891 // scroll one "page" left/top, 1892 // align first visible item of the "page" at the low padding edge. 1893 while (!prependOneVisibleItem()) { 1894 List<Integer> positions = 1895 mGrid.getItemPositionsInRows(mFirstVisiblePos, pos)[row]; 1896 firstView = getViewByPosition(positions.get(0)); 1897 if (viewMax - getViewMin(firstView) > clientSize) { 1898 if (positions.size() > 1) { 1899 firstView = getViewByPosition(positions.get(1)); 1900 } 1901 break; 1902 } 1903 } 1904 } 1905 } else if (viewMax > clientSize + paddingLow) { 1906 // view enters high padding area: 1907 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1908 // scroll whole one page right/bottom, align view at the low padding edge. 1909 firstView = view; 1910 do { 1911 List<Integer> positions = 1912 mGrid.getItemPositionsInRows(pos, mLastVisiblePos)[row]; 1913 lastView = getViewByPosition(positions.get(positions.size() - 1)); 1914 if (getViewMax(lastView) - viewMin > clientSize) { 1915 lastView = null; 1916 break; 1917 } 1918 } while (!appendOneVisibleItem()); 1919 if (lastView != null) { 1920 // however if we reached end, we should align last view. 1921 firstView = null; 1922 } 1923 } else { 1924 lastView = view; 1925 } 1926 } 1927 int scrollPrimary = 0; 1928 int scrollSecondary = 0; 1929 if (firstView != null) { 1930 scrollPrimary = getViewMin(firstView) - paddingLow; 1931 } else if (lastView != null) { 1932 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 1933 } 1934 View secondaryAlignedView; 1935 if (firstView != null) { 1936 secondaryAlignedView = firstView; 1937 } else if (lastView != null) { 1938 secondaryAlignedView = lastView; 1939 } else { 1940 secondaryAlignedView = view; 1941 } 1942 int viewCenterSecondary = mScrollOffsetSecondary + 1943 getViewCenterSecondary(secondaryAlignedView); 1944 mWindowAlignment.secondAxis().updateScrollCenter(viewCenterSecondary); 1945 scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(); 1946 scrollSecondary -= mScrollOffsetSecondary; 1947 scrollGrid(scrollPrimary, scrollSecondary, smooth); 1948 } 1949 1950 private void scrollToAlignedPosition(View view, boolean smooth) { 1951 int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 1952 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 1953 if (DEBUG) { 1954 Log.v(getTag(), "scrollAligned smooth=" + smooth + " pos=" + mFocusPosition + " " 1955 + viewCenterPrimary +","+viewCenterSecondary + " " + mWindowAlignment); 1956 } 1957 1958 if (mInLayout || viewCenterPrimary != mWindowAlignment.mainAxis().getScrollCenter() 1959 || viewCenterSecondary != mWindowAlignment.secondAxis().getScrollCenter()) { 1960 mWindowAlignment.mainAxis().updateScrollCenter(viewCenterPrimary); 1961 mWindowAlignment.secondAxis().updateScrollCenter(viewCenterSecondary); 1962 int scrollPrimary = mWindowAlignment.mainAxis().getSystemScrollPos(); 1963 int scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(); 1964 if (DEBUG) { 1965 Log.v(getTag(), "scrollAligned " + scrollPrimary + " " + scrollSecondary 1966 +" " + mWindowAlignment); 1967 } 1968 1969 scrollPrimary -= mScrollOffsetPrimary; 1970 scrollSecondary -= mScrollOffsetSecondary; 1971 1972 scrollGrid(scrollPrimary, scrollSecondary, smooth); 1973 } 1974 } 1975 1976 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 1977 if (mInLayout) { 1978 scrollDirectionPrimary(scrollPrimary); 1979 scrollDirectionSecondary(scrollSecondary); 1980 } else { 1981 int scrollX; 1982 int scrollY; 1983 if (mOrientation == HORIZONTAL) { 1984 scrollX = scrollPrimary; 1985 scrollY = scrollSecondary; 1986 } else { 1987 scrollX = scrollSecondary; 1988 scrollY = scrollPrimary; 1989 } 1990 if (smooth) { 1991 mBaseGridView.smoothScrollBy(scrollX, scrollY); 1992 } else { 1993 mBaseGridView.scrollBy(scrollX, scrollY); 1994 } 1995 } 1996 } 1997 1998 public void setAnimateChildLayout(boolean animateChildLayout) { 1999 mAnimateChildLayout = animateChildLayout; 2000 for (int i = 0, c = getChildCount(); i < c; i++) { 2001 View v = getChildAt(i); 2002 LayoutParams p = (LayoutParams) v.getLayoutParams(); 2003 if (!mAnimateChildLayout) { 2004 p.endAnimate(); 2005 } 2006 } 2007 } 2008 2009 private void attemptRecordChildLayout() { 2010 if (!mAnimateChildLayout) { 2011 return; 2012 } 2013 for (int i = 0, c = getChildCount(); i < c; i++) { 2014 View v = getChildAt(i); 2015 ((LayoutParams) v.getLayoutParams()).recordStart(mOrientation, v); 2016 } 2017 } 2018 2019 private void attemptAnimateLayoutChild() { 2020 if (!mAnimateChildLayout) { 2021 return; 2022 } 2023 for (int i = 0, c = getChildCount(); i < c; i++) { 2024 // TODO: start delay can be staggered 2025 View v = getChildAt(i); 2026 ((LayoutParams) v.getLayoutParams()).startAnimate(v, 2027 getChildLayoutAnimationDuration(), 0, getChildLayoutAnimationInterpolator()); 2028 } 2029 } 2030 2031 public boolean isChildLayoutAnimated() { 2032 return mAnimateChildLayout; 2033 } 2034 2035 public void setPruneChild(boolean pruneChild) { 2036 if (mPruneChild != pruneChild) { 2037 mPruneChild = pruneChild; 2038 if (mPruneChild) { 2039 removeInvisibleViewsAtEnd(); 2040 removeInvisibleViewsAtFront(); 2041 } 2042 } 2043 } 2044 2045 public boolean getPruneChild() { 2046 return mPruneChild; 2047 } 2048 2049 public void setChildLayoutAnimationInterpolator(Interpolator interpolator) { 2050 mAnimateLayoutChildInterpolator = interpolator; 2051 } 2052 2053 public Interpolator getChildLayoutAnimationInterpolator() { 2054 return mAnimateLayoutChildInterpolator; 2055 } 2056 2057 public void setChildLayoutAnimationDuration(long duration) { 2058 mAnimateLayoutChildDuration = duration; 2059 } 2060 2061 public long getChildLayoutAnimationDuration() { 2062 return mAnimateLayoutChildDuration; 2063 } 2064 2065 private int findImmediateChildIndex(View view) { 2066 while (view != null && view != mBaseGridView) { 2067 int index = mBaseGridView.indexOfChild(view); 2068 if (index >= 0) { 2069 return index; 2070 } 2071 view = (View) view.getParent(); 2072 } 2073 return NO_POSITION; 2074 } 2075 2076 void setFocusSearchDisabled(boolean disabled) { 2077 mFocusSearchDisabled = disabled; 2078 } 2079 2080 boolean isFocusSearchDisabled() { 2081 return mFocusSearchDisabled; 2082 } 2083 2084 @Override 2085 public View onInterceptFocusSearch(View focused, int direction) { 2086 if (mFocusSearchDisabled) { 2087 return focused; 2088 } 2089 return null; 2090 } 2091 2092 boolean hasNextViewInSameRow(int pos) { 2093 if (mGrid == null || pos == NO_POSITION) { 2094 return false; 2095 } 2096 final int focusedRow = mGrid.getLocation(pos).row; 2097 for (int i = 0, count = getChildCount(); i < count; i++) { 2098 int position = getPositionByIndex(i); 2099 StaggeredGrid.Location loc = mGrid.getLocation(position); 2100 if (loc != null && loc.row == focusedRow) { 2101 if (position > pos) { 2102 return true; 2103 } 2104 } 2105 } 2106 return false; 2107 } 2108 2109 boolean hasPreviousViewInSameRow(int pos) { 2110 if (mGrid == null || pos == NO_POSITION) { 2111 return false; 2112 } 2113 final int focusedRow = mGrid.getLocation(pos).row; 2114 for (int i = getChildCount() - 1; i >= 0; i--) { 2115 int position = getPositionByIndex(i); 2116 StaggeredGrid.Location loc = mGrid.getLocation(position); 2117 if (loc != null && loc.row == focusedRow) { 2118 if (position < pos) { 2119 return true; 2120 } 2121 } 2122 } 2123 return false; 2124 } 2125 2126 @Override 2127 public boolean onAddFocusables(RecyclerView recyclerView, 2128 ArrayList<View> views, int direction, int focusableMode) { 2129 if (mFocusSearchDisabled) { 2130 return true; 2131 } 2132 // If this viewgroup or one of its children currently has focus then we 2133 // consider our children for focus searching in main direction on the same row. 2134 // If this viewgroup has no focus and using focus align, we want the system 2135 // to ignore our children and pass focus to the viewgroup, which will pass 2136 // focus on to its children appropriately. 2137 // If this viewgroup has no focus and not using focus align, we want to 2138 // consider the child that does not overlap with padding area. 2139 if (recyclerView.hasFocus()) { 2140 final int movement = getMovement(direction); 2141 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2142 // Move on secondary direction uses default addFocusables(). 2143 return false; 2144 } 2145 final View focused = recyclerView.findFocus(); 2146 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2147 // Add focusables of focused item. 2148 if (focusedPos != NO_POSITION) { 2149 getViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2150 } 2151 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2152 mGrid.getLocation(focusedPos).row : NO_POSITION; 2153 // Add focusables of next neighbor of same row on the focus search direction. 2154 if (mGrid != null) { 2155 final int focusableCount = views.size(); 2156 for (int i = 0, count = getChildCount(); i < count; i++) { 2157 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2158 final View child = getChildAt(index); 2159 if (child.getVisibility() != View.VISIBLE) { 2160 continue; 2161 } 2162 int position = getPositionByIndex(index); 2163 StaggeredGrid.Location loc = mGrid.getLocation(position); 2164 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2165 if (focusedPos == NO_POSITION || 2166 (movement == NEXT_ITEM && position > focusedPos) 2167 || (movement == PREV_ITEM && position < focusedPos)) { 2168 child.addFocusables(views, direction, focusableMode); 2169 if (views.size() > focusableCount) { 2170 break; 2171 } 2172 } 2173 } 2174 } 2175 } 2176 } else { 2177 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2178 // adding views not overlapping padding area to avoid scrolling in gaining focus 2179 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2180 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2181 int focusableCount = views.size(); 2182 for (int i = 0, count = getChildCount(); i < count; i++) { 2183 View child = getChildAt(i); 2184 if (child.getVisibility() == View.VISIBLE) { 2185 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2186 child.addFocusables(views, direction, focusableMode); 2187 } 2188 } 2189 } 2190 // if we cannot find any, then just add all children. 2191 if (views.size() == focusableCount) { 2192 for (int i = 0, count = getChildCount(); i < count; i++) { 2193 View child = getChildAt(i); 2194 if (child.getVisibility() == View.VISIBLE) { 2195 child.addFocusables(views, direction, focusableMode); 2196 } 2197 } 2198 if (views.size() != focusableCount) { 2199 return true; 2200 } 2201 } else { 2202 return true; 2203 } 2204 // if still cannot find any, fall through and add itself 2205 } 2206 if (recyclerView.isFocusable()) { 2207 views.add(recyclerView); 2208 } 2209 } 2210 return true; 2211 } 2212 2213 @Override 2214 public View onFocusSearchFailed(View focused, int direction, Adapter adapter, 2215 Recycler recycler) { 2216 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2217 2218 View view = null; 2219 int movement = getMovement(direction); 2220 final FocusFinder ff = FocusFinder.getInstance(); 2221 if (movement == NEXT_ITEM) { 2222 while (view == null && !appendOneVisibleItem()) { 2223 view = ff.findNextFocus(mBaseGridView, focused, direction); 2224 } 2225 } else if (movement == PREV_ITEM){ 2226 while (view == null && !prependOneVisibleItem()) { 2227 view = ff.findNextFocus(mBaseGridView, focused, direction); 2228 } 2229 } 2230 if (view == null) { 2231 // returning the same view to prevent focus lost when scrolling past the end of the list 2232 if (movement == PREV_ITEM) { 2233 view = mFocusOutFront ? null : focused; 2234 } else if (movement == NEXT_ITEM){ 2235 view = mFocusOutEnd ? null : focused; 2236 } 2237 } 2238 if (DEBUG) Log.v(getTag(), "returning view " + view); 2239 return view; 2240 } 2241 2242 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2243 Rect previouslyFocusedRect) { 2244 switch (mFocusScrollStrategy) { 2245 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2246 default: 2247 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2248 direction, previouslyFocusedRect); 2249 case BaseGridView.FOCUS_SCROLL_PAGE: 2250 case BaseGridView.FOCUS_SCROLL_ITEM: 2251 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2252 direction, previouslyFocusedRect); 2253 } 2254 } 2255 2256 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2257 int direction, Rect previouslyFocusedRect) { 2258 View view = getViewByPosition(mFocusPosition); 2259 if (view != null) { 2260 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2261 if (!result && DEBUG) { 2262 Log.w(getTag(), "failed to request focus on " + view); 2263 } 2264 return result; 2265 } 2266 return false; 2267 } 2268 2269 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2270 int direction, Rect previouslyFocusedRect) { 2271 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2272 int index; 2273 int increment; 2274 int end; 2275 int count = getChildCount(); 2276 if ((direction & View.FOCUS_FORWARD) != 0) { 2277 index = 0; 2278 increment = 1; 2279 end = count; 2280 } else { 2281 index = count - 1; 2282 increment = -1; 2283 end = -1; 2284 } 2285 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2286 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2287 for (int i = index; i != end; i += increment) { 2288 View child = getChildAt(i); 2289 if (child.getVisibility() == View.VISIBLE) { 2290 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2291 if (child.requestFocus(direction, previouslyFocusedRect)) { 2292 return true; 2293 } 2294 } 2295 } 2296 } 2297 return false; 2298 } 2299 2300 private final static int PREV_ITEM = 0; 2301 private final static int NEXT_ITEM = 1; 2302 private final static int PREV_ROW = 2; 2303 private final static int NEXT_ROW = 3; 2304 2305 private int getMovement(int direction) { 2306 int movement = View.FOCUS_LEFT; 2307 2308 if (mOrientation == HORIZONTAL) { 2309 switch(direction) { 2310 case View.FOCUS_LEFT: 2311 movement = PREV_ITEM; 2312 break; 2313 case View.FOCUS_RIGHT: 2314 movement = NEXT_ITEM; 2315 break; 2316 case View.FOCUS_UP: 2317 movement = PREV_ROW; 2318 break; 2319 case View.FOCUS_DOWN: 2320 movement = NEXT_ROW; 2321 break; 2322 } 2323 } else if (mOrientation == VERTICAL) { 2324 switch(direction) { 2325 case View.FOCUS_LEFT: 2326 movement = PREV_ROW; 2327 break; 2328 case View.FOCUS_RIGHT: 2329 movement = NEXT_ROW; 2330 break; 2331 case View.FOCUS_UP: 2332 movement = PREV_ITEM; 2333 break; 2334 case View.FOCUS_DOWN: 2335 movement = NEXT_ITEM; 2336 break; 2337 } 2338 } 2339 2340 return movement; 2341 } 2342 2343 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2344 int focusIndex = getIndexByPosition(mFocusPosition); 2345 if (focusIndex == NO_POSITION) { 2346 return i; 2347 } 2348 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2349 // drawing order is 0 1 2 3 9 8 7 6 5 4 2350 if (i < focusIndex) { 2351 return i; 2352 } else if (i < childCount - 1) { 2353 return focusIndex + childCount - 1 - i; 2354 } else { 2355 return focusIndex; 2356 } 2357 } 2358 2359 @Override 2360 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2361 RecyclerView.Adapter newAdapter) { 2362 discardLayoutInfo(); 2363 super.onAdapterChanged(oldAdapter, newAdapter); 2364 } 2365 2366 private void discardLayoutInfo() { 2367 mGrid = null; 2368 mRows = null; 2369 mRowSizeSecondary = null; 2370 mFirstVisiblePos = -1; 2371 mLastVisiblePos = -1; 2372 mRowSecondarySizeRefresh = false; 2373 } 2374 2375 public void setLayoutEnabled(boolean layoutEnabled) { 2376 if (mLayoutEnabled != layoutEnabled) { 2377 mLayoutEnabled = layoutEnabled; 2378 requestLayout(); 2379 } 2380 } 2381} 2382