ListRowPresenter.java revision e43e9266c4b7e4902fefb5d2a0cacca90a3d2681
1/* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except 5 * in compliance with the License. You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software distributed under the License 10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express 11 * or implied. See the License for the specific language governing permissions and limitations under 12 * the License. 13 */ 14package android.support.v17.leanback.widget; 15 16import java.util.ArrayList; 17 18import android.content.Context; 19import android.content.res.TypedArray; 20import android.graphics.Canvas; 21import android.support.v17.leanback.R; 22import android.support.v17.leanback.graphics.ColorOverlayDimmer; 23import android.support.v17.leanback.widget.Presenter.ViewHolder; 24import android.support.v7.widget.RecyclerView; 25import android.util.AttributeSet; 26import android.view.View; 27import android.view.ViewGroup; 28import android.view.ViewGroup.LayoutParams; 29import android.widget.FrameLayout; 30 31/** 32 * ListRowPresenter renders {@link ListRow} using a 33 * {@link HorizontalGridView} hosted in a {@link ListRowView}. 34 * 35 * <h3>Hover card</h3> 36 * Optionally, {@link #setHoverCardPresenterSelector(PresenterSelector)} can be used to 37 * display a view for the currently focused list item below the rendered 38 * list. This view is known as a hover card. 39 * 40 * <h3>Selection animation</h3> 41 * ListRowPresenter disables {@link RowPresenter}'s default dimming effect and draw 42 * a dim overlay on top of each individual child items. Subclass may override and disable 43 * {@link #isUsingDefaultListSelectEffect()} and write its own dim effect in 44 * {@link #onSelectLevelChanged(RowPresenter.ViewHolder)}. 45 * 46 * <h3>Shadow</h3> 47 * ListRowPresenter applies a default shadow to child of each view. Call 48 * {@link #setShadowEnabled(boolean)} to disable shadow. Subclass may override and return 49 * false in {@link #isUsingDefaultShadow()} and replace with its own shadow implementation. 50 */ 51public class ListRowPresenter extends RowPresenter { 52 53 private static final String TAG = "ListRowPresenter"; 54 private static final boolean DEBUG = false; 55 56 public static class ViewHolder extends RowPresenter.ViewHolder { 57 final ListRowPresenter mListRowPresenter; 58 final HorizontalGridView mGridView; 59 final ItemBridgeAdapter mItemBridgeAdapter = new ItemBridgeAdapter(); 60 final HorizontalHoverCardSwitcher mHoverCardViewSwitcher = new HorizontalHoverCardSwitcher(); 61 final ColorOverlayDimmer mColorDimmer; 62 final int mPaddingTop; 63 final int mPaddingBottom; 64 final int mPaddingLeft; 65 final int mPaddingRight; 66 67 public ViewHolder(View rootView, HorizontalGridView gridView, ListRowPresenter p) { 68 super(rootView); 69 mGridView = gridView; 70 mListRowPresenter = p; 71 mColorDimmer = ColorOverlayDimmer.createDefault(rootView.getContext()); 72 mPaddingTop = mGridView.getPaddingTop(); 73 mPaddingBottom = mGridView.getPaddingBottom(); 74 mPaddingLeft = mGridView.getPaddingLeft(); 75 mPaddingRight = mGridView.getPaddingRight(); 76 } 77 78 public final ListRowPresenter getListRowPresenter() { 79 return mListRowPresenter; 80 } 81 82 public final HorizontalGridView getGridView() { 83 return mGridView; 84 } 85 } 86 87 private int mRowHeight; 88 private int mExpandedRowHeight; 89 private PresenterSelector mHoverCardPresenterSelector; 90 private int mZoomFactor; 91 private boolean mShadowEnabled = true; 92 private int mBrowseRowsFadingEdgeLength = -1; 93 94 /** 95 * Constructs a ListRowPresenter with defaults. 96 * Uses {@link FocusHighlight#ZOOM_FACTOR_MEDIUM} for focus zooming. 97 */ 98 public ListRowPresenter() { 99 this(FocusHighlight.ZOOM_FACTOR_MEDIUM); 100 } 101 102 /** 103 * Constructs a ListRowPresenter with the given parameters. 104 * 105 * @param zoomFactor Controls the zoom factor used when an item view is focused. One of 106 * {@link FocusHighlight#ZOOM_FACTOR_NONE}, 107 * {@link FocusHighlight#ZOOM_FACTOR_SMALL}, 108 * {@link FocusHighlight#ZOOM_FACTOR_MEDIUM}, 109 * {@link FocusHighlight#ZOOM_FACTOR_LARGE} 110 */ 111 public ListRowPresenter(int zoomFactor) { 112 mZoomFactor = zoomFactor; 113 } 114 115 /** 116 * Sets the row height for rows created by this Presenter. Rows 117 * created before calling this method will not be updated. 118 * 119 * @param rowHeight Row height in pixels, or WRAP_CONTENT, or 0 120 * to use the default height. 121 */ 122 public void setRowHeight(int rowHeight) { 123 mRowHeight = rowHeight; 124 } 125 126 /** 127 * Returns the row height for list rows created by this Presenter. 128 */ 129 public int getRowHeight() { 130 return mRowHeight; 131 } 132 133 /** 134 * Sets the expanded row height for rows created by this Presenter. 135 * If not set, expanded rows have the same height as unexpanded 136 * rows. 137 * 138 * @param rowHeight The row height in to use when the row is expanded, 139 * in pixels, or WRAP_CONTENT, or 0 to use the default. 140 */ 141 public void setExpandedRowHeight(int rowHeight) { 142 mExpandedRowHeight = rowHeight; 143 } 144 145 /** 146 * Returns the expanded row height for rows created by this Presenter. 147 */ 148 public int getExpandedRowHeight() { 149 return mExpandedRowHeight != 0 ? mExpandedRowHeight : mRowHeight; 150 } 151 152 /** 153 * Returns the zoom factor used for focus highlighting. 154 */ 155 public final int getZoomFactor() { 156 return mZoomFactor; 157 } 158 159 private ItemBridgeAdapter.Wrapper mCardWrapper = new ItemBridgeAdapter.Wrapper() { 160 @Override 161 public View createWrapper(View root) { 162 ShadowOverlayContainer wrapper = new ShadowOverlayContainer(root.getContext()); 163 wrapper.setLayoutParams( 164 new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT)); 165 wrapper.initialize(needsDefaultShadow(), needsDefaultListSelectEffect()); 166 return wrapper; 167 } 168 @Override 169 public void wrap(View wrapper, View wrapped) { 170 ((ShadowOverlayContainer) wrapper).wrap(wrapped); 171 } 172 }; 173 174 @Override 175 protected void initializeRowViewHolder(RowPresenter.ViewHolder holder) { 176 super.initializeRowViewHolder(holder); 177 final ViewHolder rowViewHolder = (ViewHolder) holder; 178 if (needsDefaultListSelectEffect() || needsDefaultShadow()) { 179 rowViewHolder.mItemBridgeAdapter.setWrapper(mCardWrapper); 180 } 181 if (needsDefaultListSelectEffect()) { 182 ShadowOverlayContainer.prepareParentForShadow(rowViewHolder.mGridView); 183 ((ViewGroup) rowViewHolder.view).setClipChildren(false); 184 if (rowViewHolder.mContainerViewHolder != null) { 185 ((ViewGroup) rowViewHolder.mContainerViewHolder.view).setClipChildren(false); 186 } 187 } 188 FocusHighlightHelper.setupBrowseItemFocusHighlight(rowViewHolder.mItemBridgeAdapter, mZoomFactor); 189 rowViewHolder.mGridView.setOnChildSelectedListener( 190 new OnChildSelectedListener() { 191 @Override 192 public void onChildSelected(ViewGroup parent, View view, int position, long id) { 193 selectChildView(rowViewHolder, view); 194 } 195 }); 196 rowViewHolder.mItemBridgeAdapter.setAdapterListener( 197 new ItemBridgeAdapter.AdapterListener() { 198 @Override 199 public void onCreate(final ItemBridgeAdapter.ViewHolder viewHolder) { 200 // Only when having an OnItemClickListner, we will attach the OnClickListener. 201 if (getOnItemClickedListener() != null) { 202 viewHolder.mHolder.view.setOnClickListener(new View.OnClickListener() { 203 @Override 204 public void onClick(View v) { 205 ItemBridgeAdapter.ViewHolder ibh = (ItemBridgeAdapter.ViewHolder) 206 rowViewHolder.mGridView.getChildViewHolder(viewHolder.itemView); 207 if (getOnItemClickedListener() != null) { 208 getOnItemClickedListener().onItemClicked(ibh.mItem, 209 (ListRow) rowViewHolder.mRow); 210 } 211 } 212 }); 213 } 214 } 215 216 @Override 217 public void onAttachedToWindow(ItemBridgeAdapter.ViewHolder viewHolder) { 218 if (viewHolder.itemView instanceof ShadowOverlayContainer) { 219 int dimmedColor = rowViewHolder.mColorDimmer.getPaint().getColor(); 220 ((ShadowOverlayContainer) viewHolder.itemView).setOverlayColor(dimmedColor); 221 } 222 viewHolder.itemView.setActivated(rowViewHolder.mExpanded); 223 } 224 }); 225 } 226 227 final boolean needsDefaultListSelectEffect() { 228 return isUsingDefaultListSelectEffect() && getSelectEffectEnabled(); 229 } 230 231 /** 232 * Set {@link PresenterSelector} used for showing a select object in a hover card. 233 */ 234 public final void setHoverCardPresenterSelector(PresenterSelector selector) { 235 mHoverCardPresenterSelector = selector; 236 } 237 238 /** 239 * Get {@link PresenterSelector} used for showing a select object in a hover card. 240 */ 241 public final PresenterSelector getHoverCardPresenterSelector() { 242 return mHoverCardPresenterSelector; 243 } 244 245 /* 246 * Perform operations when a child of horizontal grid view is selected. 247 */ 248 private void selectChildView(ViewHolder rowViewHolder, View view) { 249 ItemBridgeAdapter.ViewHolder ibh = null; 250 if (view != null) { 251 ibh = (ItemBridgeAdapter.ViewHolder) 252 rowViewHolder.mGridView.getChildViewHolder(view); 253 } 254 if (view == null) { 255 if (mHoverCardPresenterSelector != null) { 256 rowViewHolder.mHoverCardViewSwitcher.unselect(); 257 } 258 if (getOnItemSelectedListener() != null) { 259 getOnItemSelectedListener().onItemSelected(null, rowViewHolder.mRow); 260 } 261 } else if (rowViewHolder.mExpanded && rowViewHolder.mSelected) { 262 if (mHoverCardPresenterSelector != null) { 263 rowViewHolder.mHoverCardViewSwitcher.select(rowViewHolder.mGridView, view, 264 ibh.mItem); 265 } 266 if (getOnItemSelectedListener() != null) { 267 getOnItemSelectedListener().onItemSelected(ibh.mItem, rowViewHolder.mRow); 268 } 269 } 270 } 271 272 @Override 273 protected RowPresenter.ViewHolder createRowViewHolder(ViewGroup parent) { 274 ListRowView rowView = new ListRowView(parent.getContext()); 275 setupFadingEffect(rowView); 276 if (mRowHeight != 0) { 277 rowView.getGridView().setRowHeight(mRowHeight); 278 } 279 return new ViewHolder(rowView, rowView.getGridView(), this); 280 } 281 282 @Override 283 protected void onRowViewSelected(RowPresenter.ViewHolder holder, boolean selected) { 284 super.onRowViewSelected(holder, selected); 285 updateFooterViewSwitcher((ViewHolder) holder); 286 } 287 288 /* 289 * Show or hide hover card when row selection or expanded state is changed. 290 */ 291 private void updateFooterViewSwitcher(ViewHolder vh) { 292 if (vh.mExpanded && vh.mSelected) { 293 if (mHoverCardPresenterSelector != null) { 294 vh.mHoverCardViewSwitcher.init((ViewGroup) vh.view, 295 mHoverCardPresenterSelector); 296 } 297 ItemBridgeAdapter.ViewHolder ibh = (ItemBridgeAdapter.ViewHolder) 298 vh.mGridView.findViewHolderForPosition( 299 vh.mGridView.getSelectedPosition()); 300 selectChildView(vh, ibh == null ? null : ibh.itemView); 301 } else { 302 if (mHoverCardPresenterSelector != null) { 303 vh.mHoverCardViewSwitcher.unselect(); 304 } 305 } 306 } 307 308 private void setupFadingEffect(ListRowView rowView) { 309 // content is completely faded at 1/2 padding of left, fading length is 1/2 of padding. 310 HorizontalGridView gridView = rowView.getGridView(); 311 if (mBrowseRowsFadingEdgeLength < 0) { 312 TypedArray ta = gridView.getContext() 313 .obtainStyledAttributes(R.styleable.LeanbackTheme); 314 mBrowseRowsFadingEdgeLength = (int) ta.getDimension( 315 R.styleable.LeanbackTheme_browseRowsFadingEdgeLength, 0); 316 ta.recycle(); 317 } 318 gridView.setFadingLeftEdgeLength(mBrowseRowsFadingEdgeLength); 319 } 320 321 @Override 322 protected void onRowViewExpanded(RowPresenter.ViewHolder holder, boolean expanded) { 323 super.onRowViewExpanded(holder, expanded); 324 ViewHolder vh = (ViewHolder) holder; 325 if (getRowHeight() != getExpandedRowHeight()) { 326 int newHeight = expanded ? getExpandedRowHeight() : getRowHeight(); 327 vh.getGridView().setRowHeight(newHeight); 328 } 329 if (expanded) { 330 vh.getGridView().setPadding(vh.mPaddingLeft, vh.mPaddingTop, 331 vh.mPaddingRight, vh.mPaddingBottom); 332 } else { 333 vh.getGridView().setPadding(vh.mPaddingLeft, vh.mPaddingTop, 334 vh.mPaddingRight, 0); 335 } 336 vh.getGridView().setFadingLeftEdge(!expanded); 337 updateFooterViewSwitcher(vh); 338 } 339 340 @Override 341 protected void onBindRowViewHolder(RowPresenter.ViewHolder holder, Object item) { 342 super.onBindRowViewHolder(holder, item); 343 ViewHolder vh = (ViewHolder) holder; 344 ListRow rowItem = (ListRow) item; 345 vh.mItemBridgeAdapter.clear(); 346 vh.mItemBridgeAdapter.setAdapter(rowItem.getAdapter()); 347 vh.mGridView.setAdapter(vh.mItemBridgeAdapter); 348 } 349 350 @Override 351 protected void onUnbindRowViewHolder(RowPresenter.ViewHolder holder) { 352 ((ViewHolder) holder).mGridView.setAdapter(null); 353 super.onUnbindRowViewHolder(holder); 354 } 355 356 /** 357 * ListRowPresenter overrides the default select effect of {@link RowPresenter} 358 * and return false. 359 */ 360 @Override 361 public final boolean isUsingDefaultSelectEffect() { 362 return false; 363 } 364 365 /** 366 * Returns true so that default select effect is applied to each individual 367 * child of {@link HorizontalGridView}. Subclass may return false to disable 368 * the default implementation. 369 * @see #onSelectLevelChanged(RowPresenter.ViewHolder) 370 */ 371 public boolean isUsingDefaultListSelectEffect() { 372 return true; 373 } 374 375 /** 376 * Returns true if SDK >= 18, where default shadow 377 * is applied to each individual child of {@link HorizontalGridView}. 378 * Subclass may return false to disable. 379 */ 380 public boolean isUsingDefaultShadow() { 381 return ShadowOverlayContainer.supportsShadow(); 382 } 383 384 /** 385 * Enable or disable child shadow. 386 * This is not only for enable/disable default shadow implementation but also subclass must 387 * respect this flag. 388 */ 389 public final void setShadowEnabled(boolean enabled) { 390 mShadowEnabled = enabled; 391 } 392 393 /** 394 * Returns true if child shadow is enabled. 395 * This is not only for enable/disable default shadow implementation but also subclass must 396 * respect this flag. 397 */ 398 public final boolean getShadowEnabled() { 399 return mShadowEnabled; 400 } 401 402 final boolean needsDefaultShadow() { 403 return isUsingDefaultShadow() && getShadowEnabled(); 404 } 405 406 @Override 407 public boolean canDrawOutOfBounds() { 408 return needsDefaultShadow(); 409 } 410 411 /** 412 * Applies select level to header and draw a default color dim over each child 413 * of {@link HorizontalGridView}. 414 * <p> 415 * Subclass may override this method. A subclass 416 * needs to call super.onSelectLevelChanged() for applying header select level 417 * and optionally applying a default select level to each child view of 418 * {@link HorizontalGridView} if {@link #isUsingDefaultListSelectEffect()} 419 * is true. Subclass may override {@link #isUsingDefaultListSelectEffect()} to return 420 * false and deal with the individual item select level by itself. 421 * </p> 422 */ 423 @Override 424 protected void onSelectLevelChanged(RowPresenter.ViewHolder holder) { 425 super.onSelectLevelChanged(holder); 426 if (needsDefaultListSelectEffect()) { 427 ViewHolder vh = (ViewHolder) holder; 428 vh.mColorDimmer.setActiveLevel(holder.mSelectLevel); 429 int dimmedColor = vh.mColorDimmer.getPaint().getColor(); 430 for (int i = 0, count = vh.mGridView.getChildCount(); i < count; i++) { 431 ShadowOverlayContainer wrapper = (ShadowOverlayContainer) vh.mGridView.getChildAt(i); 432 wrapper.setOverlayColor(dimmedColor); 433 } 434 if (vh.mGridView.getFadingLeftEdge()) { 435 vh.mGridView.invalidate(); 436 } 437 } 438 } 439 440} 441