GridLayoutManager.java revision dc362d4642900b852df2dd63e98848b6621cbe92
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 * The scroll offsets of the viewport relative to the entire view. 294 */ 295 private int mScrollOffsetPrimary; 296 private int mScrollOffsetSecondary; 297 298 /** 299 * User-specified row height/column width. Can be WRAP_CONTENT. 300 */ 301 private int mRowSizeSecondaryRequested; 302 303 /** 304 * The fixed size of each grid item in the secondary direction. This corresponds to 305 * the row height, equal for all rows. Grid items may have variable length 306 * in the primary direction. 307 */ 308 private int mFixedRowSizeSecondary; 309 310 /** 311 * Tracks the secondary size of each row. 312 */ 313 private int[] mRowSizeSecondary; 314 315 /** 316 * Flag controlling whether the current/next layout should 317 * be updating the secondary size of rows. 318 */ 319 private boolean mRowSecondarySizeRefresh; 320 321 /** 322 * The maximum measured size of the view. 323 */ 324 private int mMaxSizeSecondary; 325 326 /** 327 * Margin between items. 328 */ 329 private int mHorizontalMargin; 330 /** 331 * Margin between items vertically. 332 */ 333 private int mVerticalMargin; 334 /** 335 * Margin in main direction. 336 */ 337 private int mMarginPrimary; 338 /** 339 * Margin in second direction. 340 */ 341 private int mMarginSecondary; 342 /** 343 * How to position child in secondary direction. 344 */ 345 private int mGravity = Gravity.LEFT | Gravity.TOP; 346 /** 347 * The number of rows in the grid. 348 */ 349 private int mNumRows; 350 /** 351 * Number of rows requested, can be 0 to be determined by parent size and 352 * rowHeight. 353 */ 354 private int mNumRowsRequested = 1; 355 356 /** 357 * Tracking start/end position of each row for visible items. 358 */ 359 private StaggeredGrid.Row[] mRows; 360 361 /** 362 * Saves grid information of each view. 363 */ 364 private StaggeredGrid mGrid; 365 /** 366 * Position of first item (included) that has attached views. 367 */ 368 private int mFirstVisiblePos; 369 /** 370 * Position of last item (included) that has attached views. 371 */ 372 private int mLastVisiblePos; 373 374 /** 375 * Focus Scroll strategy. 376 */ 377 private int mFocusScrollStrategy = BaseGridView.FOCUS_SCROLL_ALIGNED; 378 /** 379 * Defines how item view is aligned in the window. 380 */ 381 private final WindowAlignment mWindowAlignment = new WindowAlignment(); 382 383 /** 384 * Defines how item view is aligned. 385 */ 386 private final ItemAlignment mItemAlignment = new ItemAlignment(); 387 388 /** 389 * Dimensions of the view, width or height depending on orientation. 390 */ 391 private int mSizePrimary; 392 393 /** 394 * Allow DPAD key to navigate out at the front of the View (where position = 0), 395 * default is false. 396 */ 397 private boolean mFocusOutFront; 398 399 /** 400 * Allow DPAD key to navigate out at the end of the view, default is false. 401 */ 402 private boolean mFocusOutEnd; 403 404 /** 405 * True if focus search is disabled. 406 */ 407 private boolean mFocusSearchDisabled; 408 409 /** 410 * Animate layout changes from a child resizing or adding/removing a child. 411 */ 412 private boolean mAnimateChildLayout = true; 413 414 /** 415 * Interpolator used to animate layout of children. 416 */ 417 private Interpolator mAnimateLayoutChildInterpolator = sDefaultAnimationChildLayoutInterpolator; 418 419 /** 420 * Duration used to animate layout of children. 421 */ 422 private long mAnimateLayoutChildDuration = DEFAULT_CHILD_ANIMATION_DURATION_MS; 423 424 public GridLayoutManager(BaseGridView baseGridView) { 425 mBaseGridView = baseGridView; 426 } 427 428 public void setOrientation(int orientation) { 429 if (orientation != HORIZONTAL && orientation != VERTICAL) { 430 if (DEBUG) Log.v(getTag(), "invalid orientation: " + orientation); 431 return; 432 } 433 434 mOrientation = orientation; 435 mWindowAlignment.setOrientation(orientation); 436 mItemAlignment.setOrientation(orientation); 437 mForceFullLayout = true; 438 } 439 440 public int getFocusScrollStrategy() { 441 return mFocusScrollStrategy; 442 } 443 444 public void setFocusScrollStrategy(int focusScrollStrategy) { 445 mFocusScrollStrategy = focusScrollStrategy; 446 } 447 448 public void setWindowAlignment(int windowAlignment) { 449 mWindowAlignment.mainAxis().setWindowAlignment(windowAlignment); 450 } 451 452 public int getWindowAlignment() { 453 return mWindowAlignment.mainAxis().getWindowAlignment(); 454 } 455 456 public void setWindowAlignmentOffset(int alignmentOffset) { 457 mWindowAlignment.mainAxis().setWindowAlignmentOffset(alignmentOffset); 458 } 459 460 public int getWindowAlignmentOffset() { 461 return mWindowAlignment.mainAxis().getWindowAlignmentOffset(); 462 } 463 464 public void setWindowAlignmentOffsetPercent(float offsetPercent) { 465 mWindowAlignment.mainAxis().setWindowAlignmentOffsetPercent(offsetPercent); 466 } 467 468 public float getWindowAlignmentOffsetPercent() { 469 return mWindowAlignment.mainAxis().getWindowAlignmentOffsetPercent(); 470 } 471 472 public void setItemAlignmentOffset(int alignmentOffset) { 473 mItemAlignment.mainAxis().setItemAlignmentOffset(alignmentOffset); 474 updateChildAlignments(); 475 } 476 477 public int getItemAlignmentOffset() { 478 return mItemAlignment.mainAxis().getItemAlignmentOffset(); 479 } 480 481 public void setItemAlignmentOffsetPercent(float offsetPercent) { 482 mItemAlignment.mainAxis().setItemAlignmentOffsetPercent(offsetPercent); 483 updateChildAlignments(); 484 } 485 486 public float getItemAlignmentOffsetPercent() { 487 return mItemAlignment.mainAxis().getItemAlignmentOffsetPercent(); 488 } 489 490 public void setItemAlignmentViewId(int viewId) { 491 mItemAlignment.mainAxis().setItemAlignmentViewId(viewId); 492 updateChildAlignments(); 493 } 494 495 public int getItemAlignmentViewId() { 496 return mItemAlignment.mainAxis().getItemAlignmentViewId(); 497 } 498 499 public void setFocusOutAllowed(boolean throughFront, boolean throughEnd) { 500 mFocusOutFront = throughFront; 501 mFocusOutEnd = throughEnd; 502 } 503 504 public void setNumRows(int numRows) { 505 if (numRows < 0) throw new IllegalArgumentException(); 506 mNumRowsRequested = numRows; 507 mForceFullLayout = true; 508 } 509 510 /** 511 * Set the row height. May be WRAP_CONTENT, or a size in pixels. 512 */ 513 public void setRowHeight(int height) { 514 if (height >= 0 || height == ViewGroup.LayoutParams.WRAP_CONTENT) { 515 mRowSizeSecondaryRequested = height; 516 } else { 517 throw new IllegalArgumentException("Invalid row height: " + height); 518 } 519 } 520 521 public void setItemMargin(int margin) { 522 mVerticalMargin = mHorizontalMargin = margin; 523 mMarginPrimary = mMarginSecondary = margin; 524 } 525 526 public void setVerticalMargin(int margin) { 527 if (mOrientation == HORIZONTAL) { 528 mMarginSecondary = mVerticalMargin = margin; 529 } else { 530 mMarginPrimary = mVerticalMargin = margin; 531 } 532 } 533 534 public void setHorizontalMargin(int margin) { 535 if (mOrientation == HORIZONTAL) { 536 mMarginPrimary = mHorizontalMargin = margin; 537 } else { 538 mMarginSecondary = mHorizontalMargin = margin; 539 } 540 } 541 542 public int getVerticalMargin() { 543 return mVerticalMargin; 544 } 545 546 public int getHorizontalMargin() { 547 return mHorizontalMargin; 548 } 549 550 public void setGravity(int gravity) { 551 mGravity = gravity; 552 } 553 554 protected boolean hasDoneFirstLayout() { 555 return mGrid != null; 556 } 557 558 public void setOnChildSelectedListener(OnChildSelectedListener listener) { 559 mChildSelectedListener = listener; 560 } 561 562 private int getPositionByView(View view) { 563 return getPositionByIndex(mBaseGridView.indexOfChild(view)); 564 } 565 566 private int getPositionByIndex(int index) { 567 if (index < 0) { 568 return NO_POSITION; 569 } 570 return mFirstVisiblePos + index; 571 } 572 573 private View getViewByPosition(int position) { 574 int index = getIndexByPosition(position); 575 if (index < 0) { 576 return null; 577 } 578 return getChildAt(index); 579 } 580 581 private int getIndexByPosition(int position) { 582 if (mFirstVisiblePos < 0 || 583 position < mFirstVisiblePos || position > mLastVisiblePos) { 584 return NO_POSITION; 585 } 586 return position - mFirstVisiblePos; 587 } 588 589 private void dispatchChildSelected() { 590 if (mChildSelectedListener == null) { 591 return; 592 } 593 594 View view = getViewByPosition(mFocusPosition); 595 596 if (mFocusPosition != NO_POSITION) { 597 mChildSelectedListener.onChildSelected(mBaseGridView, view, mFocusPosition, 598 mAdapter.getItemId(mFocusPosition)); 599 } else { 600 mChildSelectedListener.onChildSelected(mBaseGridView, null, NO_POSITION, NO_ID); 601 } 602 } 603 604 @Override 605 public boolean canScrollHorizontally() { 606 // We can scroll horizontally if we have horizontal orientation, or if 607 // we are vertical and have more than one column. 608 return mOrientation == HORIZONTAL || mNumRows > 1; 609 } 610 611 @Override 612 public boolean canScrollVertically() { 613 // We can scroll vertically if we have vertical orientation, or if we 614 // are horizontal and have more than one row. 615 return mOrientation == VERTICAL || mNumRows > 1; 616 } 617 618 @Override 619 public RecyclerView.LayoutParams generateDefaultLayoutParams() { 620 return new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, 621 ViewGroup.LayoutParams.WRAP_CONTENT); 622 } 623 624 @Override 625 public RecyclerView.LayoutParams generateLayoutParams(Context context, AttributeSet attrs) { 626 return new LayoutParams(context, attrs); 627 } 628 629 @Override 630 public RecyclerView.LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) { 631 if (lp instanceof LayoutParams) { 632 return new LayoutParams((LayoutParams) lp); 633 } else if (lp instanceof RecyclerView.LayoutParams) { 634 return new LayoutParams((RecyclerView.LayoutParams) lp); 635 } else if (lp instanceof MarginLayoutParams) { 636 return new LayoutParams((MarginLayoutParams) lp); 637 } else { 638 return new LayoutParams(lp); 639 } 640 } 641 642 protected View getViewForPosition(int position) { 643 View v = mRecycler.getViewForPosition(mAdapter, position); 644 if (v != null) { 645 ((LayoutParams) v.getLayoutParams()).onViewAttached(); 646 } 647 return v; 648 } 649 650 final int getOpticalLeft(View v) { 651 return ((LayoutParams) v.getLayoutParams()).getOpticalLeft(v); 652 } 653 654 final int getOpticalRight(View v) { 655 return ((LayoutParams) v.getLayoutParams()).getOpticalRight(v); 656 } 657 658 final int getOpticalTop(View v) { 659 return ((LayoutParams) v.getLayoutParams()).getOpticalTop(v); 660 } 661 662 final int getOpticalBottom(View v) { 663 return ((LayoutParams) v.getLayoutParams()).getOpticalBottom(v); 664 } 665 666 private int getViewMin(View v) { 667 return (mOrientation == HORIZONTAL) ? getOpticalLeft(v) : getOpticalTop(v); 668 } 669 670 private int getViewMax(View v) { 671 return (mOrientation == HORIZONTAL) ? getOpticalRight(v) : getOpticalBottom(v); 672 } 673 674 private int getViewCenter(View view) { 675 return (mOrientation == HORIZONTAL) ? getViewCenterX(view) : getViewCenterY(view); 676 } 677 678 private int getViewCenterSecondary(View view) { 679 return (mOrientation == HORIZONTAL) ? getViewCenterY(view) : getViewCenterX(view); 680 } 681 682 private int getViewCenterX(View v) { 683 LayoutParams p = (LayoutParams) v.getLayoutParams(); 684 return p.getOpticalLeft(v) + p.getAlignX(); 685 } 686 687 private int getViewCenterY(View v) { 688 LayoutParams p = (LayoutParams) v.getLayoutParams(); 689 return p.getOpticalTop(v) + p.getAlignY(); 690 } 691 692 private void setViewLayoutForward(View v, boolean layoutForward) { 693 LayoutParams p = (LayoutParams) v.getLayoutParams(); 694 p.mLayoutForward = layoutForward; 695 } 696 697 private boolean getIsViewLayoutForward(View v) { 698 return ((LayoutParams) v.getLayoutParams()).mLayoutForward; 699 } 700 701 /** 702 * Re-initialize data structures for a data change or handling invisible 703 * selection. The method tries its best to preserve position information so 704 * that staggered grid looks same before and after re-initialize. 705 * @param focusPosition The initial focusPosition that we would like to 706 * focus on. 707 * @return Actual position that can be focused on. 708 */ 709 private int init(RecyclerView.Adapter adapter, RecyclerView.Recycler recycler, 710 int focusPosition) { 711 712 final int newItemCount = adapter.getItemCount(); 713 714 if (focusPosition == NO_POSITION && newItemCount > 0) { 715 // if focus position is never set before, initialize it to 0 716 focusPosition = 0; 717 } 718 // If adapter has changed then caches are invalid; otherwise, 719 // we try to maintain each row's position if number of rows keeps the same 720 // and existing mGrid contains the focusPosition. 721 if (mRows != null && mNumRows == mRows.length && 722 mGrid != null && mGrid.getSize() > 0 && focusPosition >= 0 && 723 focusPosition >= mGrid.getFirstIndex() && 724 focusPosition <= mGrid.getLastIndex()) { 725 // strip mGrid to a subset (like a column) that contains focusPosition 726 mGrid.stripDownTo(focusPosition); 727 // make sure that remaining items do not exceed new adapter size 728 int firstIndex = mGrid.getFirstIndex(); 729 int lastIndex = mGrid.getLastIndex(); 730 if (DEBUG) { 731 Log .v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " + lastIndex); 732 } 733 for (int i = lastIndex; i >=firstIndex; i--) { 734 if (i >= newItemCount) { 735 mGrid.removeLast(); 736 } 737 } 738 if (mGrid.getSize() == 0) { 739 focusPosition = newItemCount - 1; 740 // initialize row start locations 741 for (int i = 0; i < mNumRows; i++) { 742 mRows[i].low = 0; 743 mRows[i].high = 0; 744 } 745 if (DEBUG) Log.v(getTag(), "mGrid zero size"); 746 } else { 747 // initialize row start locations 748 for (int i = 0; i < mNumRows; i++) { 749 mRows[i].low = Integer.MAX_VALUE; 750 mRows[i].high = Integer.MIN_VALUE; 751 } 752 firstIndex = mGrid.getFirstIndex(); 753 lastIndex = mGrid.getLastIndex(); 754 if (focusPosition > lastIndex) { 755 focusPosition = mGrid.getLastIndex(); 756 } 757 if (DEBUG) { 758 Log.v(getTag(), "mGrid firstIndex " + firstIndex + " lastIndex " 759 + lastIndex + " focusPosition " + focusPosition); 760 } 761 // fill rows with minimal view positions of the subset 762 for (int i = firstIndex; i <= lastIndex; i++) { 763 View v = getViewByPosition(i); 764 if (v == null) { 765 continue; 766 } 767 int row = mGrid.getLocation(i).row; 768 int low = getViewMin(v) + mScrollOffsetPrimary; 769 if (low < mRows[row].low) { 770 mRows[row].low = mRows[row].high = low; 771 } 772 } 773 // fill other rows that does not include the subset using first item 774 int firstItemRowPosition = mRows[mGrid.getLocation(firstIndex).row].low; 775 if (firstItemRowPosition == Integer.MAX_VALUE) { 776 firstItemRowPosition = 0; 777 } 778 for (int i = 0; i < mNumRows; i++) { 779 if (mRows[i].low == Integer.MAX_VALUE) { 780 mRows[i].low = mRows[i].high = firstItemRowPosition; 781 } 782 } 783 } 784 785 // Same adapter, we can reuse any attached views 786 detachAndScrapAttachedViews(recycler); 787 788 } else { 789 // otherwise recreate data structure 790 mRows = new StaggeredGrid.Row[mNumRows]; 791 mRowSizeSecondary = new int[mNumRows]; 792 793 for (int i = 0; i < mNumRows; i++) { 794 mRows[i] = new StaggeredGrid.Row(); 795 } 796 mGrid = new StaggeredGridDefault(); 797 if (newItemCount == 0) { 798 focusPosition = NO_POSITION; 799 } else if (focusPosition >= newItemCount) { 800 focusPosition = newItemCount - 1; 801 } 802 803 // Adapter may have changed so remove all attached views permanently 804 removeAllViews(); 805 806 mScrollOffsetPrimary = 0; 807 mScrollOffsetSecondary = 0; 808 mWindowAlignment.reset(); 809 } 810 811 mAdapter = adapter; 812 mRecycler = recycler; 813 mGrid.setProvider(mGridProvider); 814 // mGrid share the same Row array information 815 mGrid.setRows(mRows); 816 mFirstVisiblePos = mLastVisiblePos = NO_POSITION; 817 818 initScrollController(); 819 updateScrollSecondAxis(); 820 821 return focusPosition; 822 } 823 824 private int getRowSizeSecondary(int rowIndex) { 825 if (mFixedRowSizeSecondary != 0) { 826 return mFixedRowSizeSecondary; 827 } 828 if (mRowSizeSecondary == null) { 829 return 0; 830 } 831 return mRowSizeSecondary[rowIndex]; 832 } 833 834 private int getRowStartSecondary(int rowIndex) { 835 int start = 0; 836 for (int i = 0; i < rowIndex; i++) { 837 start += getRowSizeSecondary(i) + mMarginSecondary; 838 } 839 return start; 840 } 841 842 private int getSizeSecondary() { 843 return getRowStartSecondary(mNumRows - 1) + getRowSizeSecondary(mNumRows - 1); 844 } 845 846 private boolean processRowSizeSecondary(boolean measure) { 847 if (mFixedRowSizeSecondary != 0) { 848 return false; 849 } 850 851 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 852 boolean changed = false; 853 854 for (int rowIndex = 0; rowIndex < mNumRows; rowIndex++) { 855 int rowSize = 0; 856 857 final int rowItemCount = rows[rowIndex].size(); 858 if (DEBUG) Log.v(getTag(), "processRowSizeSecondary row " + rowIndex + 859 " rowItemCount " + rowItemCount); 860 861 for (int i = 0; i < rowItemCount; i++) { 862 final int position = rows[rowIndex].get(i); 863 final View view = getViewByPosition(position); 864 if (measure && view.isLayoutRequested()) { 865 measureChild(view, rowIndex); 866 } 867 // If this view isn't visible, we ignore it. 868 if (getOpticalRight(view) < 0 || getOpticalLeft(view) > getWidth() || 869 getOpticalBottom(view) < 0 || getOpticalTop(view) > getHeight()) { 870 continue; 871 } 872 final int secondarySize = mOrientation == HORIZONTAL ? 873 view.getMeasuredHeight() : view.getMeasuredWidth(); 874 if (secondarySize > rowSize) { 875 rowSize = secondarySize; 876 } 877 } 878 if (DEBUG) Log.v(getTag(), "row " + rowIndex + " rowItemCount " + rowItemCount + 879 " rowSize " + rowSize); 880 881 if (mRowSizeSecondary[rowIndex] != rowSize) { 882 if (DEBUG) Log.v(getTag(), "row size secondary changed: " + mRowSizeSecondary[rowIndex] + 883 ", " + rowSize); 884 885 mRowSizeSecondary[rowIndex] = rowSize; 886 changed = true; 887 } 888 } 889 890 return changed; 891 } 892 893 /** 894 * Checks if we need to update row secondary sizes. 895 */ 896 private void updateRowSecondarySizeRefresh() { 897 mRowSecondarySizeRefresh = processRowSizeSecondary(false); 898 if (mRowSecondarySizeRefresh) { 899 if (DEBUG) Log.v(getTag(), "mRowSecondarySizeRefresh now set"); 900 forceRequestLayout(); 901 } 902 } 903 904 private void forceRequestLayout() { 905 if (DEBUG) Log.v(getTag(), "forceRequestLayout"); 906 // RecyclerView prevents us from requesting layout in many cases 907 // (during layout, during scroll, etc.) 908 // For secondary row size wrap_content support we currently need a 909 // second layout pass to update the measured size after having measured 910 // and added child views in layoutChildren. 911 // Force the second layout by posting a delayed runnable. 912 // TODO: investigate allowing a second layout pass, 913 // or move child add/measure logic to the measure phase. 914 mBaseGridView.getHandler().post(new Runnable() { 915 @Override 916 public void run() { 917 if (DEBUG) Log.v(getTag(), "request Layout from runnable"); 918 requestLayout(); 919 } 920 }); 921 } 922 923 @Override 924 public void onMeasure(int widthSpec, int heightSpec) { 925 int sizePrimary, sizeSecondary, modeSecondary, paddingSecondary; 926 int measuredSizeSecondary; 927 if (mOrientation == HORIZONTAL) { 928 sizePrimary = MeasureSpec.getSize(widthSpec); 929 sizeSecondary = MeasureSpec.getSize(heightSpec); 930 modeSecondary = MeasureSpec.getMode(heightSpec); 931 paddingSecondary = getPaddingTop() + getPaddingBottom(); 932 } else { 933 sizeSecondary = MeasureSpec.getSize(widthSpec); 934 sizePrimary = MeasureSpec.getSize(heightSpec); 935 modeSecondary = MeasureSpec.getMode(widthSpec); 936 paddingSecondary = getPaddingLeft() + getPaddingRight(); 937 } 938 if (DEBUG) Log.v(getTag(), "onMeasure widthSpec " + Integer.toHexString(widthSpec) + 939 " heightSpec " + Integer.toHexString(heightSpec) + 940 " modeSecondary " + Integer.toHexString(modeSecondary) + 941 " sizeSecondary " + sizeSecondary + " " + this); 942 943 mMaxSizeSecondary = sizeSecondary; 944 945 if (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) { 946 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 947 mFixedRowSizeSecondary = 0; 948 949 // Measure all current children and update cached row heights 950 if (mGrid != null) { 951 processRowSizeSecondary(true); 952 } 953 954 switch (modeSecondary) { 955 case MeasureSpec.UNSPECIFIED: 956 measuredSizeSecondary = getSizeSecondary() + paddingSecondary; 957 break; 958 case MeasureSpec.AT_MOST: 959 measuredSizeSecondary = Math.min(getSizeSecondary() + paddingSecondary, 960 mMaxSizeSecondary); 961 break; 962 case MeasureSpec.EXACTLY: 963 measuredSizeSecondary = mMaxSizeSecondary; 964 break; 965 default: 966 throw new IllegalStateException("wrong spec"); 967 } 968 969 } else { 970 switch (modeSecondary) { 971 case MeasureSpec.UNSPECIFIED: 972 if (mRowSizeSecondaryRequested == 0) { 973 if (mOrientation == HORIZONTAL) { 974 throw new IllegalStateException("Must specify rowHeight or view height"); 975 } else { 976 throw new IllegalStateException("Must specify columnWidth or view width"); 977 } 978 } 979 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 980 mNumRows = mNumRowsRequested == 0 ? 1 : mNumRowsRequested; 981 measuredSizeSecondary = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 982 * (mNumRows - 1) + paddingSecondary; 983 break; 984 case MeasureSpec.AT_MOST: 985 case MeasureSpec.EXACTLY: 986 if (mNumRowsRequested == 0 && mRowSizeSecondaryRequested == 0) { 987 mNumRows = 1; 988 mFixedRowSizeSecondary = sizeSecondary - paddingSecondary; 989 } else if (mNumRowsRequested == 0) { 990 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 991 mNumRows = (sizeSecondary + mMarginSecondary) 992 / (mRowSizeSecondaryRequested + mMarginSecondary); 993 } else if (mRowSizeSecondaryRequested == 0) { 994 mNumRows = mNumRowsRequested; 995 mFixedRowSizeSecondary = (sizeSecondary - paddingSecondary - mMarginSecondary 996 * (mNumRows - 1)) / mNumRows; 997 } else { 998 mNumRows = mNumRowsRequested; 999 mFixedRowSizeSecondary = mRowSizeSecondaryRequested; 1000 } 1001 measuredSizeSecondary = sizeSecondary; 1002 if (modeSecondary == MeasureSpec.AT_MOST) { 1003 int childrenSize = mFixedRowSizeSecondary * mNumRows + mMarginSecondary 1004 * (mNumRows - 1) + paddingSecondary; 1005 if (childrenSize < measuredSizeSecondary) { 1006 measuredSizeSecondary = childrenSize; 1007 } 1008 } 1009 break; 1010 default: 1011 throw new IllegalStateException("wrong spec"); 1012 } 1013 } 1014 if (mOrientation == HORIZONTAL) { 1015 setMeasuredDimension(sizePrimary, measuredSizeSecondary); 1016 } else { 1017 setMeasuredDimension(measuredSizeSecondary, sizePrimary); 1018 } 1019 if (DEBUG) { 1020 Log.v(getTag(), "onMeasure sizePrimary " + sizePrimary + 1021 " measuredSizeSecondary " + measuredSizeSecondary + 1022 " mFixedRowSizeSecondary " + mFixedRowSizeSecondary + 1023 " mNumRows " + mNumRows); 1024 } 1025 } 1026 1027 private void measureChild(View child, int rowIndex) { 1028 final ViewGroup.LayoutParams lp = child.getLayoutParams(); 1029 final int secondarySpec = (mRowSizeSecondaryRequested == ViewGroup.LayoutParams.WRAP_CONTENT) ? 1030 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED) : 1031 MeasureSpec.makeMeasureSpec(mFixedRowSizeSecondary, MeasureSpec.EXACTLY); 1032 int widthSpec, heightSpec; 1033 1034 if (mOrientation == HORIZONTAL) { 1035 widthSpec = ViewGroup.getChildMeasureSpec( 1036 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1037 0, lp.width); 1038 heightSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.height); 1039 } else { 1040 heightSpec = ViewGroup.getChildMeasureSpec( 1041 MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 1042 0, lp.height); 1043 widthSpec = ViewGroup.getChildMeasureSpec(secondarySpec, 0, lp.width); 1044 } 1045 1046 child.measure(widthSpec, heightSpec); 1047 1048 if (DEBUG) Log.v(getTag(), "measureChild secondarySpec " + Integer.toHexString(secondarySpec) + 1049 " widthSpec " + Integer.toHexString(widthSpec) + 1050 " heightSpec " + Integer.toHexString(heightSpec) + 1051 " measuredWidth " + child.getMeasuredWidth() + 1052 " measuredHeight " + child.getMeasuredHeight()); 1053 if (DEBUG) Log.v(getTag(), "child lp width " + lp.width + " height " + lp.height); 1054 } 1055 1056 private StaggeredGrid.Provider mGridProvider = new StaggeredGrid.Provider() { 1057 1058 @Override 1059 public int getCount() { 1060 return mAdapter.getItemCount(); 1061 } 1062 1063 @Override 1064 public void createItem(int index, int rowIndex, boolean append) { 1065 View v = getViewForPosition(index); 1066 if (mFirstVisiblePos >= 0) { 1067 // when StaggeredGrid append or prepend item, we must guarantee 1068 // that sibling item has created views already. 1069 if (append && index != mLastVisiblePos + 1) { 1070 throw new RuntimeException(); 1071 } else if (!append && index != mFirstVisiblePos - 1) { 1072 throw new RuntimeException(); 1073 } 1074 } 1075 1076 if (append) { 1077 addView(v); 1078 } else { 1079 addView(v, 0); 1080 } 1081 1082 measureChild(v, rowIndex); 1083 1084 int length = mOrientation == HORIZONTAL ? v.getMeasuredWidth() : v.getMeasuredHeight(); 1085 int start, end; 1086 if (append) { 1087 start = mRows[rowIndex].high; 1088 if (start != mRows[rowIndex].low) { 1089 // if there are existing item in the row, add margin between 1090 start += mMarginPrimary; 1091 } else { 1092 final int lastRow = mRows.length - 1; 1093 if (lastRow != rowIndex && mRows[lastRow].high != mRows[lastRow].low) { 1094 // if there are existing item in the last row, insert 1095 // the new item after the last item of last row. 1096 start = mRows[lastRow].high + mMarginPrimary; 1097 } 1098 } 1099 end = start + length; 1100 mRows[rowIndex].high = end; 1101 } else { 1102 end = mRows[rowIndex].low; 1103 if (end != mRows[rowIndex].high) { 1104 end -= mMarginPrimary; 1105 } else if (0 != rowIndex && mRows[0].high != mRows[0].low) { 1106 // if there are existing item in the first row, insert 1107 // the new item before the first item of first row. 1108 end = mRows[0].low - mMarginPrimary; 1109 } 1110 start = end - length; 1111 mRows[rowIndex].low = start; 1112 } 1113 if (mFirstVisiblePos < 0) { 1114 mFirstVisiblePos = mLastVisiblePos = index; 1115 } else { 1116 if (append) { 1117 mLastVisiblePos++; 1118 } else { 1119 mFirstVisiblePos--; 1120 } 1121 } 1122 if (DEBUG) Log.v(getTag(), "start " + start + " end " + end); 1123 int startSecondary = getRowStartSecondary(rowIndex) - mScrollOffsetSecondary; 1124 layoutChild(rowIndex, v, start - mScrollOffsetPrimary, end - mScrollOffsetPrimary, 1125 startSecondary); 1126 if (DEBUG) { 1127 Log.d(getTag(), "addView " + index + " " + v); 1128 } 1129 updateScrollMin(); 1130 updateScrollMax(); 1131 1132 setViewLayoutForward(v, append); 1133 } 1134 }; 1135 1136 private void layoutChild(int rowIndex, View v, int start, int end, int startSecondary) { 1137 int sizeSecondary = mOrientation == HORIZONTAL ? v.getMeasuredHeight() 1138 : v.getMeasuredWidth(); 1139 if (mFixedRowSizeSecondary > 0) { 1140 sizeSecondary = Math.min(sizeSecondary, mFixedRowSizeSecondary); 1141 } 1142 final int verticalGravity = mGravity & Gravity.VERTICAL_GRAVITY_MASK; 1143 final int horizontalGravity = mGravity & Gravity.HORIZONTAL_GRAVITY_MASK; 1144 if (mOrientation == HORIZONTAL && verticalGravity == Gravity.TOP 1145 || mOrientation == VERTICAL && horizontalGravity == Gravity.LEFT) { 1146 // do nothing 1147 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.BOTTOM 1148 || mOrientation == VERTICAL && horizontalGravity == Gravity.RIGHT) { 1149 startSecondary += getRowSizeSecondary(rowIndex) - sizeSecondary; 1150 } else if (mOrientation == HORIZONTAL && verticalGravity == Gravity.CENTER_VERTICAL 1151 || mOrientation == VERTICAL && horizontalGravity == Gravity.CENTER_HORIZONTAL) { 1152 startSecondary += (getRowSizeSecondary(rowIndex) - sizeSecondary) / 2; 1153 } 1154 int left, top, right, bottom; 1155 if (mOrientation == HORIZONTAL) { 1156 left = start; 1157 top = startSecondary; 1158 right = end; 1159 bottom = startSecondary + sizeSecondary; 1160 } else { 1161 top = start; 1162 left = startSecondary; 1163 bottom = end; 1164 right = startSecondary + sizeSecondary; 1165 } 1166 v.layout(left, top, right, bottom); 1167 updateChildOpticalInsets(v, left, top, right, bottom); 1168 updateChildAlignments(v); 1169 } 1170 1171 private void updateChildOpticalInsets(View v, int left, int top, int right, int bottom) { 1172 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1173 p.setOpticalInsets(left - v.getLeft(), top - v.getTop(), 1174 v.getRight() - right, v.getBottom() - bottom); 1175 } 1176 1177 private void updateChildAlignments(View v) { 1178 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1179 p.setAlignX(mItemAlignment.horizontal.getAlignmentPosition(v)); 1180 p.setAlignY(mItemAlignment.vertical.getAlignmentPosition(v)); 1181 } 1182 1183 private void updateChildAlignments() { 1184 for (int i = 0, c = getChildCount(); i < c; i++) { 1185 updateChildAlignments(getChildAt(i)); 1186 } 1187 } 1188 1189 private boolean needsAppendVisibleItem() { 1190 if (mLastVisiblePos < mFocusPosition) { 1191 return true; 1192 } 1193 int right = mScrollOffsetPrimary + mSizePrimary; 1194 for (int i = 0; i < mNumRows; i++) { 1195 if (mRows[i].low == mRows[i].high) { 1196 if (mRows[i].high < right) { 1197 return true; 1198 } 1199 } else if (mRows[i].high < right - mMarginPrimary) { 1200 return true; 1201 } 1202 } 1203 return false; 1204 } 1205 1206 private boolean needsPrependVisibleItem() { 1207 if (mFirstVisiblePos > mFocusPosition) { 1208 return true; 1209 } 1210 for (int i = 0; i < mNumRows; i++) { 1211 if (mRows[i].low == mRows[i].high) { 1212 if (mRows[i].low > mScrollOffsetPrimary) { 1213 return true; 1214 } 1215 } else if (mRows[i].low - mMarginPrimary > mScrollOffsetPrimary) { 1216 return true; 1217 } 1218 } 1219 return false; 1220 } 1221 1222 // Append one column if possible and return true if reach end. 1223 private boolean appendOneVisibleItem() { 1224 while (true) { 1225 if (mLastVisiblePos != NO_POSITION && mLastVisiblePos < mAdapter.getItemCount() -1 && 1226 mLastVisiblePos < mGrid.getLastIndex()) { 1227 // append invisible view of saved location till last row 1228 final int index = mLastVisiblePos + 1; 1229 final int row = mGrid.getLocation(index).row; 1230 mGridProvider.createItem(index, row, true); 1231 if (row == mNumRows - 1) { 1232 return false; 1233 } 1234 } else if ((mLastVisiblePos == NO_POSITION && mAdapter.getItemCount() > 0) || 1235 (mLastVisiblePos != NO_POSITION && 1236 mLastVisiblePos < mAdapter.getItemCount() - 1)) { 1237 mGrid.appendItems(mScrollOffsetPrimary + mSizePrimary); 1238 return false; 1239 } else { 1240 return true; 1241 } 1242 } 1243 } 1244 1245 private void appendVisibleItems() { 1246 while (needsAppendVisibleItem()) { 1247 if (appendOneVisibleItem()) { 1248 break; 1249 } 1250 } 1251 } 1252 1253 // Prepend one column if possible and return true if reach end. 1254 private boolean prependOneVisibleItem() { 1255 while (true) { 1256 if (mFirstVisiblePos > 0) { 1257 if (mFirstVisiblePos > mGrid.getFirstIndex()) { 1258 // prepend invisible view of saved location till first row 1259 final int index = mFirstVisiblePos - 1; 1260 final int row = mGrid.getLocation(index).row; 1261 mGridProvider.createItem(index, row, false); 1262 if (row == 0) { 1263 return false; 1264 } 1265 } else { 1266 mGrid.prependItems(mScrollOffsetPrimary); 1267 return false; 1268 } 1269 } else { 1270 return true; 1271 } 1272 } 1273 } 1274 1275 private void prependVisibleItems() { 1276 while (needsPrependVisibleItem()) { 1277 if (prependOneVisibleItem()) { 1278 break; 1279 } 1280 } 1281 } 1282 1283 private void removeChildAt(int position) { 1284 View v = getViewByPosition(position); 1285 if (v != null) { 1286 if (DEBUG) { 1287 Log.d(getTag(), "removeAndRecycleViewAt " + position); 1288 } 1289 ((LayoutParams) v.getLayoutParams()).onViewDetached(); 1290 removeAndRecycleViewAt(getIndexByPosition(position), mRecycler); 1291 } 1292 } 1293 1294 private void removeInvisibleViewsAtEnd() { 1295 boolean update = false; 1296 while(mLastVisiblePos > mFirstVisiblePos && mLastVisiblePos > mFocusPosition) { 1297 View view = getViewByPosition(mLastVisiblePos); 1298 if (getViewMin(view) > mSizePrimary) { 1299 removeChildAt(mLastVisiblePos); 1300 mLastVisiblePos--; 1301 update = true; 1302 } else { 1303 break; 1304 } 1305 } 1306 if (update) { 1307 updateRowsMinMax(); 1308 } 1309 } 1310 1311 private void removeInvisibleViewsAtFront() { 1312 boolean update = false; 1313 while(mLastVisiblePos > mFirstVisiblePos && mFirstVisiblePos < mFocusPosition) { 1314 View view = getViewByPosition(mFirstVisiblePos); 1315 if (getViewMax(view) < 0) { 1316 removeChildAt(mFirstVisiblePos); 1317 mFirstVisiblePos++; 1318 update = true; 1319 } else { 1320 break; 1321 } 1322 } 1323 if (update) { 1324 updateRowsMinMax(); 1325 } 1326 } 1327 1328 private void updateRowsMinMax() { 1329 if (mFirstVisiblePos < 0) { 1330 return; 1331 } 1332 for (int i = 0; i < mNumRows; i++) { 1333 mRows[i].low = Integer.MAX_VALUE; 1334 mRows[i].high = Integer.MIN_VALUE; 1335 } 1336 for (int i = mFirstVisiblePos; i <= mLastVisiblePos; i++) { 1337 View view = getViewByPosition(i); 1338 int row = mGrid.getLocation(i).row; 1339 int low = getViewMin(view) + mScrollOffsetPrimary; 1340 if (low < mRows[row].low) { 1341 mRows[row].low = low; 1342 } 1343 int high = getViewMax(view) + mScrollOffsetPrimary; 1344 if (high > mRows[row].high) { 1345 mRows[row].high = high; 1346 } 1347 } 1348 } 1349 1350 // Fast layout when there is no structure change, adapter change, etc. 1351 protected void fastRelayout() { 1352 initScrollController(); 1353 1354 List<Integer>[] rows = mGrid.getItemPositionsInRows(mFirstVisiblePos, mLastVisiblePos); 1355 1356 // relayout and repositioning views on each row 1357 for (int i = 0; i < mNumRows; i++) { 1358 List<Integer> row = rows[i]; 1359 final int startSecondary = getRowStartSecondary(i) - mScrollOffsetSecondary; 1360 for (int j = 0, size = row.size(); j < size; j++) { 1361 final int position = row.get(j); 1362 final View view = getViewByPosition(position); 1363 final boolean layoutForward = getIsViewLayoutForward(view); 1364 int primaryDelta, start, end; 1365 1366 if (mOrientation == HORIZONTAL) { 1367 final int primarySize = view.getMeasuredWidth(); 1368 if (view.isLayoutRequested()) { 1369 measureChild(view, i); 1370 } 1371 if (layoutForward) { 1372 start = getViewMin(view); 1373 end = start + view.getMeasuredWidth(); 1374 primaryDelta = view.getMeasuredWidth() - primarySize; 1375 if (primaryDelta != 0) { 1376 for (int k = j + 1; k < size; k++) { 1377 getViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1378 } 1379 } 1380 } else { 1381 end = getViewMax(view); 1382 start = end - view.getMeasuredWidth(); 1383 primaryDelta = primarySize - view.getMeasuredWidth(); 1384 if (primaryDelta != 0) { 1385 for (int k = 0; k < j; k++) { 1386 getViewByPosition(row.get(k)).offsetLeftAndRight(primaryDelta); 1387 } 1388 } 1389 } 1390 } else { 1391 final int primarySize = view.getMeasuredHeight(); 1392 if (view.isLayoutRequested()) { 1393 measureChild(view, i); 1394 } 1395 if (layoutForward) { 1396 start = getViewMin(view); 1397 end = start + view.getMeasuredHeight(); 1398 primaryDelta = view.getMeasuredHeight() - primarySize; 1399 if (primaryDelta != 0) { 1400 for (int k = j + 1; k < size; k++) { 1401 getViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1402 } 1403 } 1404 } else { 1405 end = getViewMax(view); 1406 start = end - view.getMeasuredHeight(); 1407 primaryDelta = primarySize - view.getMeasuredHeight(); 1408 if (primaryDelta != 0) { 1409 for (int k = 0; k < j; k++) { 1410 getViewByPosition(row.get(k)).offsetTopAndBottom(primaryDelta); 1411 } 1412 } 1413 } 1414 } 1415 layoutChild(i, view, start, end, startSecondary); 1416 } 1417 } 1418 1419 updateRowsMinMax(); 1420 appendVisibleItems(); 1421 prependVisibleItems(); 1422 1423 updateRowsMinMax(); 1424 updateScrollMin(); 1425 updateScrollMax(); 1426 updateScrollSecondAxis(); 1427 1428 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1429 View focusView = getViewByPosition(mFocusPosition == NO_POSITION ? 0 : mFocusPosition); 1430 scrollToView(focusView, false); 1431 } 1432 } 1433 1434 // Lays out items based on the current scroll position 1435 @Override 1436 public void onLayoutChildren(RecyclerView.Adapter adapter, RecyclerView.Recycler recycler, 1437 boolean structureChanged, RecyclerView.State state) { 1438 if (DEBUG) { 1439 Log.v(getTag(), "layoutChildren start numRows " + mNumRows + " mScrollOffsetSecondary " 1440 + mScrollOffsetSecondary + " mScrollOffsetPrimary " + mScrollOffsetPrimary 1441 + " structureChanged " + structureChanged 1442 + " mForceFullLayout " + mForceFullLayout); 1443 Log.v(getTag(), "width " + getWidth() + " height " + getHeight()); 1444 } 1445 1446 if (mNumRows == 0) { 1447 // haven't done measure yet 1448 return; 1449 } 1450 final int itemCount = adapter.getItemCount(); 1451 if (itemCount < 0) { 1452 return; 1453 } 1454 1455 mInLayout = true; 1456 1457 // Track the old focus view so we can adjust our system scroll position 1458 // so that any scroll animations happening now will remain valid. 1459 int delta = 0, deltaSecondary = 0; 1460 if (mFocusPosition != NO_POSITION 1461 && mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1462 View focusView = getViewByPosition(mFocusPosition); 1463 if (focusView != null) { 1464 delta = mWindowAlignment.mainAxis().getSystemScrollPos( 1465 getViewCenter(focusView) + mScrollOffsetPrimary) - mScrollOffsetPrimary; 1466 deltaSecondary = 1467 mWindowAlignment.secondAxis().getSystemScrollPos( 1468 getViewCenterSecondary(focusView) + mScrollOffsetSecondary) 1469 - mScrollOffsetSecondary; 1470 } 1471 } 1472 1473 boolean hasDoneFirstLayout = hasDoneFirstLayout(); 1474 if (!structureChanged && !mForceFullLayout && hasDoneFirstLayout) { 1475 fastRelayout(); 1476 } else { 1477 boolean hadFocus = mBaseGridView.hasFocus(); 1478 1479 int newFocusPosition = init(adapter, recycler, mFocusPosition); 1480 if (DEBUG) { 1481 Log.v(getTag(), "mFocusPosition " + mFocusPosition + " newFocusPosition " 1482 + newFocusPosition); 1483 } 1484 1485 // depending on result of init(), either recreating everything 1486 // or try to reuse the row start positions near mFocusPosition 1487 if (mGrid.getSize() == 0) { 1488 // this is a fresh creating all items, starting from 1489 // mFocusPosition with a estimated row index. 1490 mGrid.setStart(newFocusPosition, StaggeredGrid.START_DEFAULT); 1491 1492 // Can't track the old focus view 1493 delta = deltaSecondary = 0; 1494 1495 } else { 1496 // mGrid remembers Locations for the column that 1497 // contains mFocusePosition and also mRows remembers start 1498 // positions of each row. 1499 // Manually re-create child views for that column 1500 int firstIndex = mGrid.getFirstIndex(); 1501 int lastIndex = mGrid.getLastIndex(); 1502 for (int i = firstIndex; i <= lastIndex; i++) { 1503 mGridProvider.createItem(i, mGrid.getLocation(i).row, true); 1504 } 1505 } 1506 // add visible views at end until reach the end of window 1507 appendVisibleItems(); 1508 // add visible views at front until reach the start of window 1509 prependVisibleItems(); 1510 // multiple rounds: scrollToView of first round may drag first/last child into 1511 // "visible window" and we update scrollMin/scrollMax then run second scrollToView 1512 int oldFirstVisible; 1513 int oldLastVisible; 1514 do { 1515 oldFirstVisible = mFirstVisiblePos; 1516 oldLastVisible = mLastVisiblePos; 1517 View focusView = getViewByPosition(newFocusPosition); 1518 // we need force to initialize the child view's position 1519 scrollToView(focusView, false); 1520 if (focusView != null && hadFocus) { 1521 focusView.requestFocus(); 1522 } 1523 appendVisibleItems(); 1524 prependVisibleItems(); 1525 removeInvisibleViewsAtFront(); 1526 removeInvisibleViewsAtEnd(); 1527 } while (mFirstVisiblePos != oldFirstVisible || mLastVisiblePos != oldLastVisible); 1528 } 1529 mForceFullLayout = false; 1530 1531 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_ALIGNED) { 1532 scrollDirectionPrimary(-delta); 1533 scrollDirectionSecondary(-deltaSecondary); 1534 } 1535 appendVisibleItems(); 1536 prependVisibleItems(); 1537 removeInvisibleViewsAtFront(); 1538 removeInvisibleViewsAtEnd(); 1539 1540 if (DEBUG) { 1541 StringWriter sw = new StringWriter(); 1542 PrintWriter pw = new PrintWriter(sw); 1543 mGrid.debugPrint(pw); 1544 Log.d(getTag(), sw.toString()); 1545 } 1546 1547 removeAndRecycleScrap(recycler); 1548 attemptAnimateLayoutChild(); 1549 1550 if (mRowSecondarySizeRefresh) { 1551 mRowSecondarySizeRefresh = false; 1552 } else { 1553 updateRowSecondarySizeRefresh(); 1554 } 1555 1556 if (!hasDoneFirstLayout) { 1557 dispatchChildSelected(); 1558 } 1559 mInLayout = false; 1560 if (DEBUG) Log.v(getTag(), "layoutChildren end"); 1561 } 1562 1563 private void offsetChildrenSecondary(int increment) { 1564 final int childCount = getChildCount(); 1565 if (mOrientation == HORIZONTAL) { 1566 for (int i = 0; i < childCount; i++) { 1567 getChildAt(i).offsetTopAndBottom(increment); 1568 } 1569 } else { 1570 for (int i = 0; i < childCount; i++) { 1571 getChildAt(i).offsetLeftAndRight(increment); 1572 } 1573 } 1574 mScrollOffsetSecondary -= increment; 1575 } 1576 1577 private void offsetChildrenPrimary(int increment) { 1578 final int childCount = getChildCount(); 1579 if (mOrientation == VERTICAL) { 1580 for (int i = 0; i < childCount; i++) { 1581 getChildAt(i).offsetTopAndBottom(increment); 1582 } 1583 } else { 1584 for (int i = 0; i < childCount; i++) { 1585 getChildAt(i).offsetLeftAndRight(increment); 1586 } 1587 } 1588 mScrollOffsetPrimary -= increment; 1589 } 1590 1591 @Override 1592 public int scrollHorizontallyBy(int dx, Adapter adapter, Recycler recycler, 1593 RecyclerView.State state) { 1594 if (DEBUG) Log.v(TAG, "scrollHorizontallyBy " + dx); 1595 1596 if (mOrientation == HORIZONTAL) { 1597 return scrollDirectionPrimary(dx); 1598 } else { 1599 return scrollDirectionSecondary(dx); 1600 } 1601 } 1602 1603 @Override 1604 public int scrollVerticallyBy(int dy, Adapter adapter, Recycler recycler, 1605 RecyclerView.State state) { 1606 if (DEBUG) Log.v(TAG, "scrollVerticallyBy " + dy); 1607 if (mOrientation == VERTICAL) { 1608 return scrollDirectionPrimary(dy); 1609 } else { 1610 return scrollDirectionSecondary(dy); 1611 } 1612 } 1613 1614 // scroll in main direction may add/prune views 1615 private int scrollDirectionPrimary(int da) { 1616 offsetChildrenPrimary(-da); 1617 if (mInLayout) { 1618 return da; 1619 } 1620 1621 int childCount = getChildCount(); 1622 boolean updated; 1623 1624 if (da > 0) { 1625 appendVisibleItems(); 1626 } else if (da < 0) { 1627 prependVisibleItems(); 1628 } 1629 updated = getChildCount() > childCount; 1630 childCount = getChildCount(); 1631 1632 if (da > 0) { 1633 removeInvisibleViewsAtFront(); 1634 } else if (da < 0) { 1635 removeInvisibleViewsAtEnd(); 1636 } 1637 updated |= getChildCount() < childCount; 1638 1639 attemptAnimateLayoutChild(); 1640 if (updated) { 1641 updateRowSecondarySizeRefresh(); 1642 } 1643 1644 mBaseGridView.invalidate(); 1645 return da; 1646 } 1647 1648 // scroll in second direction will not add/prune views 1649 private int scrollDirectionSecondary(int dy) { 1650 offsetChildrenSecondary(-dy); 1651 mBaseGridView.invalidate(); 1652 return dy; 1653 } 1654 1655 private void updateScrollMax() { 1656 if (mLastVisiblePos >= 0 && mLastVisiblePos == mAdapter.getItemCount() - 1) { 1657 int maxEdge = Integer.MIN_VALUE; 1658 for (int i = 0; i < mRows.length; i++) { 1659 if (mRows[i].high > maxEdge) { 1660 maxEdge = mRows[i].high; 1661 } 1662 } 1663 mWindowAlignment.mainAxis().setMaxEdge(maxEdge); 1664 if (DEBUG) Log.v(getTag(), "updating scroll maxEdge to " + maxEdge); 1665 } 1666 } 1667 1668 private void updateScrollMin() { 1669 if (mFirstVisiblePos == 0) { 1670 int minEdge = Integer.MAX_VALUE; 1671 for (int i = 0; i < mRows.length; i++) { 1672 if (mRows[i].low < minEdge) { 1673 minEdge = mRows[i].low; 1674 } 1675 } 1676 mWindowAlignment.mainAxis().setMinEdge(minEdge); 1677 if (DEBUG) Log.v(getTag(), "updating scroll minEdge to " + minEdge); 1678 } 1679 } 1680 1681 private void updateScrollSecondAxis() { 1682 mWindowAlignment.secondAxis().setMinEdge(0); 1683 mWindowAlignment.secondAxis().setMaxEdge(getSizeSecondary()); 1684 } 1685 1686 private void initScrollController() { 1687 mWindowAlignment.horizontal.setSize(getWidth()); 1688 mWindowAlignment.horizontal.setPadding(getPaddingLeft(), getPaddingRight()); 1689 mWindowAlignment.vertical.setSize(getHeight()); 1690 mWindowAlignment.vertical.setPadding(getPaddingTop(), getPaddingBottom()); 1691 mSizePrimary = mWindowAlignment.mainAxis().getSize(); 1692 mWindowAlignment.mainAxis().invalidateScrollMin(); 1693 mWindowAlignment.mainAxis().invalidateScrollMax(); 1694 1695 if (DEBUG) { 1696 Log.v(getTag(), "initScrollController mSizePrimary " + mSizePrimary 1697 + " mWindowAlignment " + mWindowAlignment); 1698 } 1699 } 1700 1701 public void setSelection(RecyclerView parent, int position) { 1702 setSelection(parent, position, false); 1703 } 1704 1705 public void setSelectionSmooth(RecyclerView parent, int position) { 1706 setSelection(parent, position, true); 1707 } 1708 1709 public int getSelection() { 1710 return mFocusPosition; 1711 } 1712 1713 public void setSelection(RecyclerView parent, int position, boolean smooth) { 1714 if (mFocusPosition == position) { 1715 return; 1716 } 1717 View view = getViewByPosition(position); 1718 if (view != null) { 1719 scrollToView(view, smooth); 1720 } else { 1721 boolean right = position > mFocusPosition; 1722 mFocusPosition = position; 1723 if (smooth) { 1724 if (!hasDoneFirstLayout()) { 1725 Log.w(getTag(), "setSelectionSmooth should " + 1726 "not be called before first layout pass"); 1727 return; 1728 } 1729 if (right) { 1730 appendVisibleItems(); 1731 } else { 1732 prependVisibleItems(); 1733 } 1734 scrollToView(getViewByPosition(position), smooth); 1735 } else { 1736 mForceFullLayout = true; 1737 parent.requestLayout(); 1738 } 1739 } 1740 } 1741 1742 @Override 1743 public void onItemsAdded(RecyclerView recyclerView, int positionStart, int itemCount) { 1744 boolean needsLayout = false; 1745 if (itemCount != 0) { 1746 if (mFirstVisiblePos < 0) { 1747 needsLayout = true; 1748 } else if (!(positionStart > mLastVisiblePos + 1 || 1749 positionStart + itemCount < mFirstVisiblePos - 1)) { 1750 needsLayout = true; 1751 } 1752 } 1753 if (needsLayout) { 1754 recyclerView.requestLayout(); 1755 } 1756 } 1757 1758 @Override 1759 public boolean onRequestChildFocus(RecyclerView parent, View child, View focused) { 1760 if (mFocusSearchDisabled) { 1761 return true; 1762 } 1763 if (!mInLayout) { 1764 scrollToView(child, true); 1765 } 1766 return true; 1767 } 1768 1769 @Override 1770 public boolean requestChildRectangleOnScreen(RecyclerView parent, View view, Rect rect, 1771 boolean immediate) { 1772 if (DEBUG) Log.v(getTag(), "requestChildRectangleOnScreen " + view + " " + rect); 1773 return false; 1774 } 1775 1776 int getScrollOffsetX() { 1777 return mOrientation == HORIZONTAL ? mScrollOffsetPrimary : mScrollOffsetSecondary; 1778 } 1779 1780 int getScrollOffsetY() { 1781 return mOrientation == HORIZONTAL ? mScrollOffsetSecondary : mScrollOffsetPrimary; 1782 } 1783 1784 public void getViewSelectedOffsets(View view, int[] offsets) { 1785 int scrollOffsetX = getScrollOffsetX(); 1786 int scrollOffsetY = getScrollOffsetY(); 1787 int viewCenterX = scrollOffsetX + getViewCenterX(view); 1788 int viewCenterY = scrollOffsetY + getViewCenterY(view); 1789 offsets[0] = mWindowAlignment.horizontal.getSystemScrollPos(viewCenterX) - scrollOffsetX; 1790 offsets[1] = mWindowAlignment.vertical.getSystemScrollPos(viewCenterY) - scrollOffsetY; 1791 } 1792 1793 /** 1794 * Scroll to a given child view and change mFocusPosition. 1795 */ 1796 private void scrollToView(View view, boolean smooth) { 1797 int newFocusPosition = getPositionByView(view); 1798 if (mInLayout || newFocusPosition != mFocusPosition) { 1799 mFocusPosition = newFocusPosition; 1800 dispatchChildSelected(); 1801 } 1802 if (mBaseGridView.isChildrenDrawingOrderEnabledInternal()) { 1803 mBaseGridView.invalidate(); 1804 } 1805 if (view == null) { 1806 return; 1807 } 1808 if (!view.hasFocus() && mBaseGridView.hasFocus()) { 1809 // transfer focus to the child if it does not have focus yet (e.g. triggered 1810 // by setSelection()) 1811 view.requestFocus(); 1812 } 1813 switch (mFocusScrollStrategy) { 1814 case BaseGridView.FOCUS_SCROLL_ALIGNED: 1815 default: 1816 scrollToAlignedPosition(view, smooth); 1817 break; 1818 case BaseGridView.FOCUS_SCROLL_ITEM: 1819 case BaseGridView.FOCUS_SCROLL_PAGE: 1820 scrollItemOrPage(view, smooth); 1821 break; 1822 } 1823 } 1824 1825 private void scrollItemOrPage(View view, boolean smooth) { 1826 int pos = getPositionByView(view); 1827 int viewMin = getViewMin(view); 1828 int viewMax = getViewMax(view); 1829 // we either align "firstView" to left/top padding edge 1830 // or align "lastView" to right/bottom padding edge 1831 View firstView = null; 1832 View lastView = null; 1833 int paddingLow = mWindowAlignment.mainAxis().getPaddingLow(); 1834 int clientSize = mWindowAlignment.mainAxis().getClientSize(); 1835 final int row = mGrid.getLocation(pos).row; 1836 if (viewMin < paddingLow) { 1837 // view enters low padding area: 1838 firstView = view; 1839 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1840 // scroll one "page" left/top, 1841 // align first visible item of the "page" at the low padding edge. 1842 while (!prependOneVisibleItem()) { 1843 List<Integer> positions = 1844 mGrid.getItemPositionsInRows(mFirstVisiblePos, pos)[row]; 1845 firstView = getViewByPosition(positions.get(0)); 1846 if (viewMax - getViewMin(firstView) > clientSize) { 1847 if (positions.size() > 1) { 1848 firstView = getViewByPosition(positions.get(1)); 1849 } 1850 break; 1851 } 1852 } 1853 } 1854 } else if (viewMax > clientSize + paddingLow) { 1855 // view enters high padding area: 1856 if (mFocusScrollStrategy == BaseGridView.FOCUS_SCROLL_PAGE) { 1857 // scroll whole one page right/bottom, align view at the low padding edge. 1858 firstView = view; 1859 do { 1860 List<Integer> positions = 1861 mGrid.getItemPositionsInRows(pos, mLastVisiblePos)[row]; 1862 lastView = getViewByPosition(positions.get(positions.size() - 1)); 1863 if (getViewMax(lastView) - viewMin > clientSize) { 1864 lastView = null; 1865 break; 1866 } 1867 } while (!appendOneVisibleItem()); 1868 if (lastView != null) { 1869 // however if we reached end, we should align last view. 1870 firstView = null; 1871 } 1872 } else { 1873 lastView = view; 1874 } 1875 } 1876 int scrollPrimary = 0; 1877 int scrollSecondary = 0; 1878 if (firstView != null) { 1879 scrollPrimary = getViewMin(firstView) - paddingLow; 1880 } else if (lastView != null) { 1881 scrollPrimary = getViewMax(lastView) - (paddingLow + clientSize); 1882 } 1883 View secondaryAlignedView; 1884 if (firstView != null) { 1885 secondaryAlignedView = firstView; 1886 } else if (lastView != null) { 1887 secondaryAlignedView = lastView; 1888 } else { 1889 secondaryAlignedView = view; 1890 } 1891 int viewCenterSecondary = mScrollOffsetSecondary + 1892 getViewCenterSecondary(secondaryAlignedView); 1893 mWindowAlignment.secondAxis().updateScrollCenter(viewCenterSecondary); 1894 scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(); 1895 scrollSecondary -= mScrollOffsetSecondary; 1896 scrollGrid(scrollPrimary, scrollSecondary, smooth); 1897 } 1898 1899 private void scrollToAlignedPosition(View view, boolean smooth) { 1900 int viewCenterPrimary = mScrollOffsetPrimary + getViewCenter(view); 1901 int viewCenterSecondary = mScrollOffsetSecondary + getViewCenterSecondary(view); 1902 if (DEBUG) { 1903 Log.v(getTag(), "scrollAligned smooth=" + smooth + " pos=" + mFocusPosition + " " 1904 + viewCenterPrimary +","+viewCenterSecondary + " " + mWindowAlignment); 1905 } 1906 1907 if (mInLayout || viewCenterPrimary != mWindowAlignment.mainAxis().getScrollCenter() 1908 || viewCenterSecondary != mWindowAlignment.secondAxis().getScrollCenter()) { 1909 mWindowAlignment.mainAxis().updateScrollCenter(viewCenterPrimary); 1910 mWindowAlignment.secondAxis().updateScrollCenter(viewCenterSecondary); 1911 int scrollPrimary = mWindowAlignment.mainAxis().getSystemScrollPos(); 1912 int scrollSecondary = mWindowAlignment.secondAxis().getSystemScrollPos(); 1913 if (DEBUG) { 1914 Log.v(getTag(), "scrollAligned " + scrollPrimary + " " + scrollSecondary 1915 +" " + mWindowAlignment); 1916 } 1917 1918 scrollPrimary -= mScrollOffsetPrimary; 1919 scrollSecondary -= mScrollOffsetSecondary; 1920 1921 scrollGrid(scrollPrimary, scrollSecondary, smooth); 1922 } 1923 } 1924 1925 private void scrollGrid(int scrollPrimary, int scrollSecondary, boolean smooth) { 1926 if (mInLayout) { 1927 scrollDirectionPrimary(scrollPrimary); 1928 scrollDirectionSecondary(scrollSecondary); 1929 } else { 1930 int scrollX; 1931 int scrollY; 1932 if (mOrientation == HORIZONTAL) { 1933 scrollX = scrollPrimary; 1934 scrollY = scrollSecondary; 1935 } else { 1936 scrollX = scrollSecondary; 1937 scrollY = scrollPrimary; 1938 } 1939 if (smooth) { 1940 mBaseGridView.smoothScrollBy(scrollX, scrollY); 1941 } else { 1942 mBaseGridView.scrollBy(scrollX, scrollY); 1943 } 1944 } 1945 } 1946 1947 public void setAnimateChildLayout(boolean animateChildLayout) { 1948 mAnimateChildLayout = animateChildLayout; 1949 for (int i = 0, c = getChildCount(); i < c; i++) { 1950 View v = getChildAt(i); 1951 LayoutParams p = (LayoutParams) v.getLayoutParams(); 1952 if (!mAnimateChildLayout) { 1953 p.endAnimate(); 1954 } else { 1955 // record initial location values 1956 p.mFirstAttached = true; 1957 p.startAnimate(this, v, 0); 1958 } 1959 } 1960 } 1961 1962 private void attemptAnimateLayoutChild() { 1963 if (!mAnimateChildLayout) { 1964 return; 1965 } 1966 for (int i = 0, c = getChildCount(); i < c; i++) { 1967 // TODO: start delay can be staggered 1968 View v = getChildAt(i); 1969 ((LayoutParams) v.getLayoutParams()).startAnimate(this, v, 0); 1970 } 1971 } 1972 1973 public boolean isChildLayoutAnimated() { 1974 return mAnimateChildLayout; 1975 } 1976 1977 public void setChildLayoutAnimationInterpolator(Interpolator interpolator) { 1978 mAnimateLayoutChildInterpolator = interpolator; 1979 } 1980 1981 public Interpolator getChildLayoutAnimationInterpolator() { 1982 return mAnimateLayoutChildInterpolator; 1983 } 1984 1985 public void setChildLayoutAnimationDuration(long duration) { 1986 mAnimateLayoutChildDuration = duration; 1987 } 1988 1989 public long getChildLayoutAnimationDuration() { 1990 return mAnimateLayoutChildDuration; 1991 } 1992 1993 private int findImmediateChildIndex(View view) { 1994 while (view != null && view != mBaseGridView) { 1995 int index = mBaseGridView.indexOfChild(view); 1996 if (index >= 0) { 1997 return index; 1998 } 1999 view = (View) view.getParent(); 2000 } 2001 return NO_POSITION; 2002 } 2003 2004 void setFocusSearchDisabled(boolean disabled) { 2005 mFocusSearchDisabled = disabled; 2006 } 2007 2008 boolean isFocusSearchDisabled() { 2009 return mFocusSearchDisabled; 2010 } 2011 2012 @Override 2013 public View onInterceptFocusSearch(View focused, int direction) { 2014 if (mFocusSearchDisabled) { 2015 return focused; 2016 } 2017 return null; 2018 } 2019 2020 boolean hasNextViewInSameRow(int pos) { 2021 if (mGrid == null || pos == NO_POSITION) { 2022 return false; 2023 } 2024 final int focusedRow = mGrid.getLocation(pos).row; 2025 for (int i = 0, count = getChildCount(); i < count; i++) { 2026 int position = getPositionByIndex(i); 2027 StaggeredGrid.Location loc = mGrid.getLocation(position); 2028 if (loc != null && loc.row == focusedRow) { 2029 if (position > pos) { 2030 return true; 2031 } 2032 } 2033 } 2034 return false; 2035 } 2036 2037 boolean hasPreviousViewInSameRow(int pos) { 2038 if (mGrid == null || pos == NO_POSITION) { 2039 return false; 2040 } 2041 final int focusedRow = mGrid.getLocation(pos).row; 2042 for (int i = getChildCount() - 1; i >= 0; i--) { 2043 int position = getPositionByIndex(i); 2044 StaggeredGrid.Location loc = mGrid.getLocation(position); 2045 if (loc != null && loc.row == focusedRow) { 2046 if (position < pos) { 2047 return true; 2048 } 2049 } 2050 } 2051 return false; 2052 } 2053 2054 @Override 2055 public boolean onAddFocusables(RecyclerView recyclerView, 2056 ArrayList<View> views, int direction, int focusableMode) { 2057 if (mFocusSearchDisabled) { 2058 return true; 2059 } 2060 // If this viewgroup or one of its children currently has focus then we 2061 // consider our children for focus searching in main direction on the same row. 2062 // If this viewgroup has no focus and using focus align, we want the system 2063 // to ignore our children and pass focus to the viewgroup, which will pass 2064 // focus on to its children appropriately. 2065 // If this viewgroup has no focus and not using focus align, we want to 2066 // consider the child that does not overlap with padding area. 2067 if (recyclerView.hasFocus()) { 2068 final int movement = getMovement(direction); 2069 if (movement != PREV_ITEM && movement != NEXT_ITEM) { 2070 // Move on secondary direction uses default addFocusables(). 2071 return false; 2072 } 2073 final View focused = recyclerView.findFocus(); 2074 final int focusedPos = getPositionByIndex(findImmediateChildIndex(focused)); 2075 // Add focusables of focused item. 2076 if (focusedPos != NO_POSITION) { 2077 getViewByPosition(focusedPos).addFocusables(views, direction, focusableMode); 2078 } 2079 final int focusedRow = mGrid != null && focusedPos != NO_POSITION ? 2080 mGrid.getLocation(focusedPos).row : NO_POSITION; 2081 // Add focusables of next neighbor of same row on the focus search direction. 2082 if (mGrid != null) { 2083 final int focusableCount = views.size(); 2084 for (int i = 0, count = getChildCount(); i < count; i++) { 2085 int index = movement == NEXT_ITEM ? i : count - 1 - i; 2086 final View child = getChildAt(index); 2087 if (child.getVisibility() != View.VISIBLE) { 2088 continue; 2089 } 2090 int position = getPositionByIndex(index); 2091 StaggeredGrid.Location loc = mGrid.getLocation(position); 2092 if (focusedRow == NO_POSITION || (loc != null && loc.row == focusedRow)) { 2093 if (focusedPos == NO_POSITION || 2094 (movement == NEXT_ITEM && position > focusedPos) 2095 || (movement == PREV_ITEM && position < focusedPos)) { 2096 child.addFocusables(views, direction, focusableMode); 2097 if (views.size() > focusableCount) { 2098 break; 2099 } 2100 } 2101 } 2102 } 2103 } 2104 } else { 2105 if (mFocusScrollStrategy != BaseGridView.FOCUS_SCROLL_ALIGNED) { 2106 // adding views not overlapping padding area to avoid scrolling in gaining focus 2107 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2108 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2109 int focusableCount = views.size(); 2110 for (int i = 0, count = getChildCount(); i < count; i++) { 2111 View child = getChildAt(i); 2112 if (child.getVisibility() == View.VISIBLE) { 2113 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2114 child.addFocusables(views, direction, focusableMode); 2115 } 2116 } 2117 } 2118 // if we cannot find any, then just add all children. 2119 if (views.size() == focusableCount) { 2120 for (int i = 0, count = getChildCount(); i < count; i++) { 2121 View child = getChildAt(i); 2122 if (child.getVisibility() == View.VISIBLE) { 2123 child.addFocusables(views, direction, focusableMode); 2124 } 2125 } 2126 if (views.size() != focusableCount) { 2127 return true; 2128 } 2129 } else { 2130 return true; 2131 } 2132 // if still cannot find any, fall through and add itself 2133 } 2134 if (recyclerView.isFocusable()) { 2135 views.add(recyclerView); 2136 } 2137 } 2138 return true; 2139 } 2140 2141 @Override 2142 public View onFocusSearchFailed(View focused, int direction, Adapter adapter, 2143 Recycler recycler) { 2144 if (DEBUG) Log.v(getTag(), "onFocusSearchFailed direction " + direction); 2145 2146 View view = null; 2147 int movement = getMovement(direction); 2148 final FocusFinder ff = FocusFinder.getInstance(); 2149 if (movement == NEXT_ITEM) { 2150 while (view == null && !appendOneVisibleItem()) { 2151 view = ff.findNextFocus(mBaseGridView, focused, direction); 2152 } 2153 } else if (movement == PREV_ITEM){ 2154 while (view == null && !prependOneVisibleItem()) { 2155 view = ff.findNextFocus(mBaseGridView, focused, direction); 2156 } 2157 } 2158 if (view == null) { 2159 // returning the same view to prevent focus lost when scrolling past the end of the list 2160 if (movement == PREV_ITEM) { 2161 view = mFocusOutFront ? null : focused; 2162 } else if (movement == NEXT_ITEM){ 2163 view = mFocusOutEnd ? null : focused; 2164 } 2165 } 2166 if (DEBUG) Log.v(getTag(), "returning view " + view); 2167 return view; 2168 } 2169 2170 boolean gridOnRequestFocusInDescendants(RecyclerView recyclerView, int direction, 2171 Rect previouslyFocusedRect) { 2172 switch (mFocusScrollStrategy) { 2173 case BaseGridView.FOCUS_SCROLL_ALIGNED: 2174 default: 2175 return gridOnRequestFocusInDescendantsAligned(recyclerView, 2176 direction, previouslyFocusedRect); 2177 case BaseGridView.FOCUS_SCROLL_PAGE: 2178 case BaseGridView.FOCUS_SCROLL_ITEM: 2179 return gridOnRequestFocusInDescendantsUnaligned(recyclerView, 2180 direction, previouslyFocusedRect); 2181 } 2182 } 2183 2184 private boolean gridOnRequestFocusInDescendantsAligned(RecyclerView recyclerView, 2185 int direction, Rect previouslyFocusedRect) { 2186 View view = getViewByPosition(mFocusPosition); 2187 if (view != null) { 2188 boolean result = view.requestFocus(direction, previouslyFocusedRect); 2189 if (!result && DEBUG) { 2190 Log.w(getTag(), "failed to request focus on " + view); 2191 } 2192 return result; 2193 } 2194 return false; 2195 } 2196 2197 private boolean gridOnRequestFocusInDescendantsUnaligned(RecyclerView recyclerView, 2198 int direction, Rect previouslyFocusedRect) { 2199 // focus to view not overlapping padding area to avoid scrolling in gaining focus 2200 int index; 2201 int increment; 2202 int end; 2203 int count = getChildCount(); 2204 if ((direction & View.FOCUS_FORWARD) != 0) { 2205 index = 0; 2206 increment = 1; 2207 end = count; 2208 } else { 2209 index = count - 1; 2210 increment = -1; 2211 end = -1; 2212 } 2213 int left = mWindowAlignment.mainAxis().getPaddingLow(); 2214 int right = mWindowAlignment.mainAxis().getClientSize() + left; 2215 for (int i = index; i != end; i += increment) { 2216 View child = getChildAt(i); 2217 if (child.getVisibility() == View.VISIBLE) { 2218 if (getViewMin(child) >= left && getViewMax(child) <= right) { 2219 if (child.requestFocus(direction, previouslyFocusedRect)) { 2220 return true; 2221 } 2222 } 2223 } 2224 } 2225 return false; 2226 } 2227 2228 private final static int PREV_ITEM = 0; 2229 private final static int NEXT_ITEM = 1; 2230 private final static int PREV_ROW = 2; 2231 private final static int NEXT_ROW = 3; 2232 2233 private int getMovement(int direction) { 2234 int movement = View.FOCUS_LEFT; 2235 2236 if (mOrientation == HORIZONTAL) { 2237 switch(direction) { 2238 case View.FOCUS_LEFT: 2239 movement = PREV_ITEM; 2240 break; 2241 case View.FOCUS_RIGHT: 2242 movement = NEXT_ITEM; 2243 break; 2244 case View.FOCUS_UP: 2245 movement = PREV_ROW; 2246 break; 2247 case View.FOCUS_DOWN: 2248 movement = NEXT_ROW; 2249 break; 2250 } 2251 } else if (mOrientation == VERTICAL) { 2252 switch(direction) { 2253 case View.FOCUS_LEFT: 2254 movement = PREV_ROW; 2255 break; 2256 case View.FOCUS_RIGHT: 2257 movement = NEXT_ROW; 2258 break; 2259 case View.FOCUS_UP: 2260 movement = PREV_ITEM; 2261 break; 2262 case View.FOCUS_DOWN: 2263 movement = NEXT_ITEM; 2264 break; 2265 } 2266 } 2267 2268 return movement; 2269 } 2270 2271 int getChildDrawingOrder(RecyclerView recyclerView, int childCount, int i) { 2272 int focusIndex = getIndexByPosition(mFocusPosition); 2273 if (focusIndex == NO_POSITION) { 2274 return i; 2275 } 2276 // supposely 0 1 2 3 4 5 6 7 8 9, 4 is the center item 2277 // drawing order is 0 1 2 3 9 8 7 6 5 4 2278 if (i < focusIndex) { 2279 return i; 2280 } else if (i < childCount - 1) { 2281 return focusIndex + childCount - 1 - i; 2282 } else { 2283 return focusIndex; 2284 } 2285 } 2286 2287 @Override 2288 public void onAdapterChanged(RecyclerView.Adapter oldAdapter, 2289 RecyclerView.Adapter newAdapter) { 2290 mGrid = null; 2291 mRows = null; 2292 mRowSizeSecondary = null; 2293 mRowSecondarySizeRefresh = false; 2294 super.onAdapterChanged(oldAdapter, newAdapter); 2295 } 2296} 2297