RowPresenter.java revision cb959eeab2e5c791704063c021e21b831689b1e3
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.support.v17.leanback.app.HeadersFragment; 17import android.support.v17.leanback.graphics.ColorOverlayDimmer; 18import android.view.View; 19import android.view.ViewGroup; 20 21/** 22 * An abstract {@link Presenter} that renders a {@link Row}. 23 * 24 * <h3>Customize UI widgets</h3> 25 * When a subclass of RowPresenter adds UI widgets, it should subclass 26 * {@link RowPresenter.ViewHolder} and override {@link #createRowViewHolder(ViewGroup)} 27 * and {@link #initializeRowViewHolder(ViewHolder)}. The subclass must use layout id 28 * "row_content" for the widget that will be aligned to the title of any {@link HeadersFragment} 29 * that may exist in the parent fragment. RowPresenter contains an optional and 30 * replaceable {@link RowHeaderPresenter} that renders the header. You can disable 31 * the default rendering or replace the Presenter with a new header presenter 32 * by calling {@link #setHeaderPresenter(RowHeaderPresenter)}. 33 * 34 * <h3>UI events from fragments</h3> 35 * RowPresenter receives calls from its parent (typically a Fragment) when: 36 * <ul> 37 * <li> 38 * A row is selected via {@link #setRowViewSelected(Presenter.ViewHolder, boolean)}. The event 39 * is triggered immediately when there is a row selection change before the selection 40 * animation is started. Selected status may control activated status of the row (see 41 * "Activated status" below). 42 * Subclasses of RowPresenter may override {@link #onRowViewSelected(ViewHolder, boolean)}. 43 * </li> 44 * <li> 45 * A row is expanded to full height via {@link #setRowViewExpanded(Presenter.ViewHolder, boolean)} 46 * when BrowseFragment hides fast lane on the left. 47 * The event is triggered immediately before the expand animation is started. 48 * Row title is shown when row is expanded. Expanded status may control activated status 49 * of the row (see "Activated status" below). 50 * Subclasses of RowPresenter may override {@link #onRowViewExpanded(ViewHolder, boolean)}. 51 * </li> 52 * </ul> 53 * 54 * <h3>Activated status</h3> 55 * The activated status of a row is applied to the row view and it's children via 56 * {@link View#setActivated(boolean)}. 57 * The activated status is typically used to control {@link BaseCardView} info region visibility. 58 * The row's activated status can be controlled by selected status and/or expanded status. 59 * Call {@link #setSyncActivatePolicy(int)} and choose one of the four policies: 60 * <ul> 61 * <li>{@link #SYNC_ACTIVATED_TO_EXPANDED} Activated status is synced with row expanded status</li> 62 * <li>{@link #SYNC_ACTIVATED_TO_SELECTED} Activated status is synced with row selected status</li> 63 * <li>{@link #SYNC_ACTIVATED_TO_EXPANDED_AND_SELECTED} Activated status is set to true 64 * when both expanded and selected status are true</li> 65 * <li>{@link #SYNC_ACTIVATED_CUSTOM} Activated status is not controlled by selected status 66 * or expanded status, application can control activated status by its own. 67 * Application should call {@link RowPresenter.ViewHolder#setActivated(boolean)} to change 68 * activated status of row view. 69 * </li> 70 * </ul> 71 * 72 * <h3>User events</h3> 73 * RowPresenter provides {@link OnItemSelectedListener} and {@link OnItemClickedListener}. 74 * If a subclass wants to add its own {@link View.OnFocusChangeListener} or 75 * {@link View.OnClickListener}, it must do that in {@link #createRowViewHolder(ViewGroup)} 76 * to be properly chained by the library. Adding View listeners after 77 * {@link #createRowViewHolder(ViewGroup)} is undefined and may result in 78 * incorrect behavior by the library's listeners. 79 * 80 * <h3>Selection animation</h3> 81 * <p> 82 * When a user scrolls through rows, a fragment will initiate animation and call 83 * {@link #setSelectLevel(Presenter.ViewHolder, float)} with float value between 84 * 0 and 1. By default, the RowPresenter draws a dim overlay on top of the row 85 * view for views that are not selected. Subclasses may override this default effect 86 * by having {@link #isUsingDefaultSelectEffect()} return false and overriding 87 * {@link #onSelectLevelChanged(ViewHolder)} to apply a different selection effect. 88 * </p> 89 * <p> 90 * Call {@link #setSelectEffectEnabled(boolean)} to enable/disable the select effect, 91 * This will not only enable/disable the default dim effect but also subclasses must 92 * respect this flag as well. 93 * </p> 94 */ 95public abstract class RowPresenter extends Presenter { 96 97 /** 98 * Don't synchronize row view activated status with selected status or expanded status, 99 * application will do its own through {@link RowPresenter.ViewHolder#setActivated(boolean)}. 100 */ 101 public static final int SYNC_ACTIVATED_CUSTOM = 0; 102 103 /** 104 * Synchronizes row view's activated status to expand status of the row view holder. 105 */ 106 public static final int SYNC_ACTIVATED_TO_EXPANDED = 1; 107 108 /** 109 * Synchronizes row view's activated status to selected status of the row view holder. 110 */ 111 public static final int SYNC_ACTIVATED_TO_SELECTED = 2; 112 113 /** 114 * Sets the row view's activated status to true when both expand and selected are true. 115 */ 116 public static final int SYNC_ACTIVATED_TO_EXPANDED_AND_SELECTED = 3; 117 118 static class ContainerViewHolder extends Presenter.ViewHolder { 119 /** 120 * wrapped row view holder 121 */ 122 final ViewHolder mRowViewHolder; 123 124 public ContainerViewHolder(RowContainerView containerView, ViewHolder rowViewHolder) { 125 super(containerView); 126 containerView.addRowView(rowViewHolder.view); 127 if (rowViewHolder.mHeaderViewHolder != null) { 128 containerView.addHeaderView(rowViewHolder.mHeaderViewHolder.view); 129 } 130 mRowViewHolder = rowViewHolder; 131 mRowViewHolder.mContainerViewHolder = this; 132 } 133 } 134 135 /** 136 * A view holder for a {@link Row}. 137 */ 138 public static class ViewHolder extends Presenter.ViewHolder { 139 private static final int ACTIVATED_NOT_ASSIGNED = 0; 140 private static final int ACTIVATED = 1; 141 private static final int NOT_ACTIVATED = 2; 142 143 ContainerViewHolder mContainerViewHolder; 144 RowHeaderPresenter.ViewHolder mHeaderViewHolder; 145 Row mRow; 146 int mActivated = ACTIVATED_NOT_ASSIGNED; 147 boolean mSelected; 148 boolean mExpanded; 149 boolean mInitialzed; 150 float mSelectLevel = 0f; // initially unselected 151 protected final ColorOverlayDimmer mColorDimmer; 152 153 /** 154 * Constructor for ViewHolder. 155 * 156 * @param view The View bound to the Row. 157 */ 158 public ViewHolder(View view) { 159 super(view); 160 mColorDimmer = ColorOverlayDimmer.createDefault(view.getContext()); 161 } 162 163 /** 164 * Returns the Row bound to the View in this ViewHolder. 165 */ 166 public final Row getRow() { 167 return mRow; 168 } 169 170 /** 171 * Returns whether the Row is in its expanded state. 172 * 173 * @return true if the Row is expanded, false otherwise. 174 */ 175 public final boolean isExpanded() { 176 return mExpanded; 177 } 178 179 /** 180 * Returns whether the Row is selected. 181 * 182 * @return true if the Row is selected, false otherwise. 183 */ 184 public final boolean isSelected() { 185 return mSelected; 186 } 187 188 /** 189 * Returns the current selection level of the Row. 190 */ 191 public final float getSelectLevel() { 192 return mSelectLevel; 193 } 194 195 /** 196 * Returns the view holder for the Row header for this Row. 197 */ 198 public final RowHeaderPresenter.ViewHolder getHeaderViewHolder() { 199 return mHeaderViewHolder; 200 } 201 202 /** 203 * Sets the row view's activated status. The status will be applied to children through 204 * {@link #syncActivatedStatus(View)}. Application should only call this function 205 * when {@link RowPresenter#getSyncActivatePolicy()} is 206 * {@link RowPresenter#SYNC_ACTIVATED_CUSTOM}; otherwise the value will 207 * be overwritten when expanded or selected status changes. 208 */ 209 public final void setActivated(boolean activated) { 210 mActivated = activated ? ACTIVATED : NOT_ACTIVATED; 211 } 212 213 /** 214 * Synchronizes the activated status of view to the last value passed through 215 * {@link RowPresenter.ViewHolder#setActivated(boolean)}. No operation if 216 * {@link RowPresenter.ViewHolder#setActivated(boolean)} is never called. Normally 217 * application does not need to call this method, {@link ListRowPresenter} automatically 218 * calls this method when a child is attached to list row. However if 219 * application writes its own custom RowPresenter, it should call this method 220 * when attaches a child to the row view. 221 */ 222 public final void syncActivatedStatus(View view) { 223 if (mActivated == ACTIVATED) { 224 view.setActivated(true); 225 } else if (mActivated == NOT_ACTIVATED) { 226 view.setActivated(false); 227 } 228 } 229 } 230 231 private RowHeaderPresenter mHeaderPresenter = new RowHeaderPresenter(); 232 private OnItemSelectedListener mOnItemSelectedListener; 233 private OnItemClickedListener mOnItemClickedListener; 234 private OnItemViewSelectedListener mOnItemViewSelectedListener; 235 private OnItemViewClickedListener mOnItemViewClickedListener; 236 237 boolean mSelectEffectEnabled = true; 238 int mSyncActivatePolicy = SYNC_ACTIVATED_TO_EXPANDED; 239 240 /** 241 * Constructs a RowPresenter. 242 */ 243 public RowPresenter() { 244 mHeaderPresenter.setNullItemVisibilityGone(true); 245 } 246 247 @Override 248 public final Presenter.ViewHolder onCreateViewHolder(ViewGroup parent) { 249 ViewHolder vh = createRowViewHolder(parent); 250 vh.mInitialzed = false; 251 Presenter.ViewHolder result; 252 if (needsRowContainerView()) { 253 RowContainerView containerView = new RowContainerView(parent.getContext()); 254 if (mHeaderPresenter != null) { 255 vh.mHeaderViewHolder = (RowHeaderPresenter.ViewHolder) 256 mHeaderPresenter.onCreateViewHolder((ViewGroup) vh.view); 257 } 258 result = new ContainerViewHolder(containerView, vh); 259 } else { 260 result = vh; 261 } 262 initializeRowViewHolder(vh); 263 if (!vh.mInitialzed) { 264 throw new RuntimeException("super.initializeRowViewHolder() must be called"); 265 } 266 return result; 267 } 268 269 /** 270 * Called to create a ViewHolder object for a Row. Subclasses will override 271 * this method to return a different concrete ViewHolder object. 272 * 273 * @param parent The parent View for the Row's view holder. 274 * @return A ViewHolder for the Row's View. 275 */ 276 protected abstract ViewHolder createRowViewHolder(ViewGroup parent); 277 278 /** 279 * Called after a {@link RowPresenter.ViewHolder} is created for a Row. 280 * Subclasses may override this method and start by calling 281 * super.initializeRowViewHolder(ViewHolder). 282 * 283 * @param vh The ViewHolder to initialize for the Row. 284 */ 285 protected void initializeRowViewHolder(ViewHolder vh) { 286 vh.mInitialzed = true; 287 // set clip children to false for slide transition 288 if (vh.view instanceof ViewGroup) { 289 ((ViewGroup) vh.view).setClipChildren(false); 290 } 291 if (vh.mContainerViewHolder != null) { 292 ((ViewGroup) vh.mContainerViewHolder.view).setClipChildren(false); 293 } 294 } 295 296 /** 297 * Set the Presenter used for rendering the header. Can be null to disable 298 * header rendering. The method must be called before creating any Row Views. 299 */ 300 public final void setHeaderPresenter(RowHeaderPresenter headerPresenter) { 301 mHeaderPresenter = headerPresenter; 302 } 303 304 /** 305 * Get the Presenter used for rendering the header, or null if none has been 306 * set. 307 */ 308 public final RowHeaderPresenter getHeaderPresenter() { 309 return mHeaderPresenter; 310 } 311 312 /** 313 * Get the {@link RowPresenter.ViewHolder} from the given Presenter 314 * ViewHolder. 315 */ 316 public final ViewHolder getRowViewHolder(Presenter.ViewHolder holder) { 317 if (holder instanceof ContainerViewHolder) { 318 return ((ContainerViewHolder) holder).mRowViewHolder; 319 } else { 320 return (ViewHolder) holder; 321 } 322 } 323 324 /** 325 * Set the expanded state of a Row view. 326 * 327 * @param holder The Row ViewHolder to set expanded state on. 328 * @param expanded True if the Row is expanded, false otherwise. 329 */ 330 public final void setRowViewExpanded(Presenter.ViewHolder holder, boolean expanded) { 331 ViewHolder rowViewHolder = getRowViewHolder(holder); 332 rowViewHolder.mExpanded = expanded; 333 onRowViewExpanded(rowViewHolder, expanded); 334 } 335 336 /** 337 * Set the selected state of a Row view. 338 * 339 * @param holder The Row ViewHolder to set expanded state on. 340 * @param selected True if the Row is expanded, false otherwise. 341 */ 342 public final void setRowViewSelected(Presenter.ViewHolder holder, boolean selected) { 343 ViewHolder rowViewHolder = getRowViewHolder(holder); 344 rowViewHolder.mSelected = selected; 345 onRowViewSelected(rowViewHolder, selected); 346 } 347 348 /** 349 * Subclass may override this to respond to expanded state changes of a Row. 350 * The default implementation will hide/show the header view. Subclasses may 351 * make visual changes to the Row View but must not create animation on the 352 * Row view. 353 */ 354 protected void onRowViewExpanded(ViewHolder vh, boolean expanded) { 355 updateHeaderViewVisibility(vh); 356 updateActivateStatus(vh, vh.view); 357 } 358 359 /** 360 * Update view's activate status according to {@link #getSyncActivatePolicy()} and the 361 * selected status and expanded status of the RowPresenter ViewHolder. 362 */ 363 private void updateActivateStatus(ViewHolder vh, View view) { 364 switch (mSyncActivatePolicy) { 365 case SYNC_ACTIVATED_TO_EXPANDED: 366 vh.setActivated(vh.isExpanded()); 367 break; 368 case SYNC_ACTIVATED_TO_SELECTED: 369 vh.setActivated(vh.isSelected()); 370 break; 371 case SYNC_ACTIVATED_TO_EXPANDED_AND_SELECTED: 372 vh.setActivated(vh.isExpanded() && vh.isSelected()); 373 break; 374 } 375 vh.syncActivatedStatus(view); 376 } 377 378 /** 379 * Sets policy of updating row view activated status. Can be one of: 380 * <li> Default value {@link #SYNC_ACTIVATED_TO_EXPANDED} 381 * <li> {@link #SYNC_ACTIVATED_TO_SELECTED} 382 * <li> {@link #SYNC_ACTIVATED_TO_EXPANDED_AND_SELECTED} 383 * <li> {@link #SYNC_ACTIVATED_CUSTOM} 384 */ 385 public final void setSyncActivatePolicy(int syncActivatePolicy) { 386 mSyncActivatePolicy = syncActivatePolicy; 387 } 388 389 /** 390 * Returns policy of updating row view activated status. Can be one of: 391 * <li> Default value {@link #SYNC_ACTIVATED_TO_EXPANDED} 392 * <li> {@link #SYNC_ACTIVATED_TO_SELECTED} 393 * <li> {@link #SYNC_ACTIVATED_TO_EXPANDED_AND_SELECTED} 394 * <li> {@link #SYNC_ACTIVATED_CUSTOM} 395 */ 396 public final int getSyncActivatePolicy() { 397 return mSyncActivatePolicy; 398 } 399 400 /** 401 * Subclass may override this to respond to selected state changes of a Row. 402 * Subclass may make visual changes to Row view but must not create 403 * animation on the Row view. 404 */ 405 protected void onRowViewSelected(ViewHolder vh, boolean selected) { 406 if (selected) { 407 if (mOnItemViewSelectedListener != null) { 408 mOnItemViewSelectedListener.onItemSelected(null, null, vh, vh.getRow()); 409 } 410 if (mOnItemSelectedListener != null) { 411 mOnItemSelectedListener.onItemSelected(null, vh.getRow()); 412 } 413 } 414 updateHeaderViewVisibility(vh); 415 updateActivateStatus(vh, vh.view); 416 } 417 418 private void updateHeaderViewVisibility(ViewHolder vh) { 419 if (mHeaderPresenter != null && vh.mHeaderViewHolder != null) { 420 RowContainerView containerView = ((RowContainerView) vh.mContainerViewHolder.view); 421 containerView.showHeader(vh.isExpanded()); 422 } 423 } 424 425 /** 426 * Set the current select level to a value between 0 (unselected) and 1 (selected). 427 * Subclasses may override {@link #onSelectLevelChanged(ViewHolder)} to 428 * respond to changes in the selected level. 429 */ 430 public final void setSelectLevel(Presenter.ViewHolder vh, float level) { 431 ViewHolder rowViewHolder = getRowViewHolder(vh); 432 rowViewHolder.mSelectLevel = level; 433 onSelectLevelChanged(rowViewHolder); 434 } 435 436 /** 437 * Get the current select level. The value will be between 0 (unselected) 438 * and 1 (selected). 439 */ 440 public final float getSelectLevel(Presenter.ViewHolder vh) { 441 return getRowViewHolder(vh).mSelectLevel; 442 } 443 444 /** 445 * Callback when select level is changed. The default implementation applies 446 * the select level to {@link RowHeaderPresenter#setSelectLevel(RowHeaderPresenter.ViewHolder, float)} 447 * when {@link #getSelectEffectEnabled()} is true. Subclasses may override 448 * this function and implement a different select effect. In this case, you 449 * should also override {@link #isUsingDefaultSelectEffect()} to disable 450 * the default dimming effect applied by the library. 451 */ 452 protected void onSelectLevelChanged(ViewHolder vh) { 453 if (getSelectEffectEnabled()) { 454 vh.mColorDimmer.setActiveLevel(vh.mSelectLevel); 455 if (vh.mHeaderViewHolder != null) { 456 mHeaderPresenter.setSelectLevel(vh.mHeaderViewHolder, vh.mSelectLevel); 457 } 458 if (isUsingDefaultSelectEffect()) { 459 ((RowContainerView) vh.mContainerViewHolder.view).setForegroundColor( 460 vh.mColorDimmer.getPaint().getColor()); 461 } 462 } 463 } 464 465 /** 466 * Enables or disables the row selection effect. 467 * This will not only affect the default dim effect, but subclasses must 468 * respect this flag as well. 469 */ 470 public final void setSelectEffectEnabled(boolean applyDimOnSelect) { 471 mSelectEffectEnabled = applyDimOnSelect; 472 } 473 474 /** 475 * Returns true if the row selection effect is enabled. 476 * This value not only determines whether the default dim implementation is 477 * used, but subclasses must also respect this flag. 478 */ 479 public final boolean getSelectEffectEnabled() { 480 return mSelectEffectEnabled; 481 } 482 483 /** 484 * Return whether this RowPresenter is using the default dimming effect 485 * provided by the library. Subclasses may(most likely) return false and 486 * override {@link #onSelectLevelChanged(ViewHolder)}. 487 */ 488 public boolean isUsingDefaultSelectEffect() { 489 return true; 490 } 491 492 final boolean needsDefaultSelectEffect() { 493 return isUsingDefaultSelectEffect() && getSelectEffectEnabled(); 494 } 495 496 final boolean needsRowContainerView() { 497 return mHeaderPresenter != null || needsDefaultSelectEffect(); 498 } 499 500 /** 501 * Return true if the Row view can draw outside its bounds. 502 */ 503 public boolean canDrawOutOfBounds() { 504 return false; 505 } 506 507 @Override 508 public final void onBindViewHolder(Presenter.ViewHolder viewHolder, Object item) { 509 onBindRowViewHolder(getRowViewHolder(viewHolder), item); 510 } 511 512 protected void onBindRowViewHolder(ViewHolder vh, Object item) { 513 vh.mRow = (Row) item; 514 if (vh.mHeaderViewHolder != null) { 515 mHeaderPresenter.onBindViewHolder(vh.mHeaderViewHolder, item); 516 } 517 } 518 519 @Override 520 public final void onUnbindViewHolder(Presenter.ViewHolder viewHolder) { 521 onUnbindRowViewHolder(getRowViewHolder(viewHolder)); 522 } 523 524 protected void onUnbindRowViewHolder(ViewHolder vh) { 525 if (vh.mHeaderViewHolder != null) { 526 mHeaderPresenter.onUnbindViewHolder(vh.mHeaderViewHolder); 527 } 528 vh.mRow = null; 529 } 530 531 @Override 532 public final void onViewAttachedToWindow(Presenter.ViewHolder holder) { 533 onRowViewAttachedToWindow(getRowViewHolder(holder)); 534 } 535 536 protected void onRowViewAttachedToWindow(ViewHolder vh) { 537 if (vh.mHeaderViewHolder != null) { 538 mHeaderPresenter.onViewAttachedToWindow(vh.mHeaderViewHolder); 539 } 540 } 541 542 @Override 543 public final void onViewDetachedFromWindow(Presenter.ViewHolder holder) { 544 onRowViewDetachedFromWindow(getRowViewHolder(holder)); 545 } 546 547 protected void onRowViewDetachedFromWindow(ViewHolder vh) { 548 if (vh.mHeaderViewHolder != null) { 549 mHeaderPresenter.onViewDetachedFromWindow(vh.mHeaderViewHolder); 550 } 551 cancelAnimationsRecursive(vh.view); 552 } 553 554 /** 555 * Set the listener for item or row selection. A RowPresenter fires a row 556 * selection event with a null item. Subclasses (e.g. {@link ListRowPresenter}) 557 * can fire a selection event with the selected item. 558 */ 559 public final void setOnItemSelectedListener(OnItemSelectedListener listener) { 560 mOnItemSelectedListener = listener; 561 } 562 563 /** 564 * Get the listener for item or row selection. 565 */ 566 public final OnItemSelectedListener getOnItemSelectedListener() { 567 return mOnItemSelectedListener; 568 } 569 570 /** 571 * Set the listener for item click events. A RowPresenter does not use this 572 * listener, but a subclass may fire an item click event if it has the concept 573 * of an item. The {@link OnItemClickedListener} will override any 574 * {@link View.OnClickListener} that an item's Presenter sets during 575 * {@link Presenter#onCreateViewHolder(ViewGroup)}. So in general, you 576 * should choose to use an OnItemClickedListener or a {@link 577 * View.OnClickListener}, but not both. 578 */ 579 public final void setOnItemClickedListener(OnItemClickedListener listener) { 580 mOnItemClickedListener = listener; 581 } 582 583 /** 584 * Get the listener for item click events. 585 */ 586 public final OnItemClickedListener getOnItemClickedListener() { 587 return mOnItemClickedListener; 588 } 589 590 /** 591 * Set listener for item or row selection. RowPresenter fires row selection 592 * event with null item, subclass of RowPresenter e.g. {@link ListRowPresenter} can 593 * fire a selection event with selected item. 594 */ 595 public final void setOnItemViewSelectedListener(OnItemViewSelectedListener listener) { 596 mOnItemViewSelectedListener = listener; 597 } 598 599 /** 600 * Get listener for item or row selection. 601 */ 602 public final OnItemViewSelectedListener getOnItemViewSelectedListener() { 603 return mOnItemViewSelectedListener; 604 } 605 606 /** 607 * Set listener for item click event. RowPresenter does nothing but subclass of 608 * RowPresenter may fire item click event if it does have a concept of item. 609 * OnItemViewClickedListener will override {@link View.OnClickListener} that 610 * item presenter sets during {@link Presenter#onCreateViewHolder(ViewGroup)}. 611 * So in general, developer should choose one of the listeners but not both. 612 */ 613 public final void setOnItemViewClickedListener(OnItemViewClickedListener listener) { 614 mOnItemViewClickedListener = listener; 615 } 616 617 /** 618 * Set listener for item click event. 619 */ 620 public final OnItemViewClickedListener getOnItemViewClickedListener() { 621 return mOnItemViewClickedListener; 622 } 623 624 /** 625 * Freeze/Unfreeze the row, typically used when transition starts/ends. 626 * This method is called by fragment, app should not call it directly. 627 */ 628 public void freeze(ViewHolder holder, boolean freeze) { 629 } 630 631 /** 632 * Change visibility of views, entrance transition will be run against the views that 633 * change visibilities. Subclass may override and begin with calling 634 * super.setEntranceTransitionState(). This method is called by fragment, 635 * app should not call it directly. 636 */ 637 public void setEntranceTransitionState(ViewHolder holder, boolean afterTransition) { 638 if (holder.mHeaderViewHolder != null && 639 holder.mHeaderViewHolder.view.getVisibility() != View.GONE) { 640 holder.mHeaderViewHolder.view.setVisibility(afterTransition ? 641 View.VISIBLE : View.INVISIBLE); 642 } 643 } 644} 645