ListRowPresenter.java revision f272f7533fcb5aba341e9ab2f4ff0421d668a8ca
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 63 public ViewHolder(View rootView, HorizontalGridView gridView, ListRowPresenter p) { 64 super(rootView); 65 mGridView = gridView; 66 mListRowPresenter = p; 67 mColorDimmer = ColorOverlayDimmer.createDefault(rootView.getContext()); 68 } 69 70 public final ListRowPresenter getListRowPresenter() { 71 return mListRowPresenter; 72 } 73 74 public final HorizontalGridView getGridView() { 75 return mGridView; 76 } 77 } 78 79 private int mRowHeight; 80 private int mExpandedRowHeight; 81 private PresenterSelector mHoverCardPresenterSelector; 82 private int mZoomFactor; 83 private boolean mShadowEnabled = true; 84 private int mBrowseRowsFadingEdgeLength = -1; 85 86 /** 87 * Constructs a ListRowPresenter with defaults. 88 * Uses {@link FocusHighlight#ZOOM_FACTOR_MEDIUM} for focus zooming. 89 */ 90 public ListRowPresenter() { 91 this(FocusHighlight.ZOOM_FACTOR_MEDIUM); 92 } 93 94 /** 95 * Constructs a ListRowPresenter with the given parameters. 96 * 97 * @param zoomFactor Controls the zoom factor used when an item view is focused. One of 98 * {@link FocusHighlight#ZOOM_FACTOR_NONE}, 99 * {@link FocusHighlight#ZOOM_FACTOR_SMALL}, 100 * {@link FocusHighlight#ZOOM_FACTOR_MEDIUM}, 101 * {@link FocusHighlight#ZOOM_FACTOR_LARGE} 102 */ 103 public ListRowPresenter(int zoomFactor) { 104 mZoomFactor = zoomFactor; 105 } 106 107 /** 108 * Sets the row height for rows created by this Presenter. Rows 109 * created before calling this method will not be updated. 110 * 111 * @param rowHeight Row height in pixels, or WRAP_CONTENT, or 0 112 * to use the default height. 113 */ 114 public void setRowHeight(int rowHeight) { 115 mRowHeight = rowHeight; 116 } 117 118 /** 119 * Returns the row height for list rows created by this Presenter. 120 */ 121 public int getRowHeight() { 122 return mRowHeight; 123 } 124 125 /** 126 * Sets the expanded row height for rows created by this Presenter. 127 * If not set, expanded rows have the same height as unexpanded 128 * rows. 129 * 130 * @param rowHeight The row height in to use when the row is expanded, 131 * in pixels, or WRAP_CONTENT, or 0 to use the default. 132 */ 133 public void setExpandedRowHeight(int rowHeight) { 134 mExpandedRowHeight = rowHeight; 135 } 136 137 /** 138 * Returns the expanded row height for rows created by this Presenter. 139 */ 140 public int getExpandedRowHeight() { 141 return mExpandedRowHeight != 0 ? mExpandedRowHeight : mRowHeight; 142 } 143 144 /** 145 * Returns the zoom factor used for focus highlighting. 146 */ 147 public final int getZoomFactor() { 148 return mZoomFactor; 149 } 150 151 private ItemBridgeAdapter.Wrapper mCardWrapper = new ItemBridgeAdapter.Wrapper() { 152 @Override 153 public View createWrapper(View root) { 154 ShadowOverlayContainer wrapper = new ShadowOverlayContainer(root.getContext()); 155 wrapper.setLayoutParams( 156 new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT)); 157 wrapper.initialize(needsDefaultShadow(), needsDefaultListSelectEffect()); 158 return wrapper; 159 } 160 @Override 161 public void wrap(View wrapper, View wrapped) { 162 ((ShadowOverlayContainer) wrapper).wrap(wrapped); 163 } 164 }; 165 166 @Override 167 protected void initializeRowViewHolder(RowPresenter.ViewHolder holder) { 168 super.initializeRowViewHolder(holder); 169 final ViewHolder rowViewHolder = (ViewHolder) holder; 170 if (needsDefaultListSelectEffect() || needsDefaultShadow()) { 171 rowViewHolder.mItemBridgeAdapter.setWrapper(mCardWrapper); 172 } 173 if (needsDefaultListSelectEffect()) { 174 ShadowOverlayContainer.prepareParentForShadow(rowViewHolder.mGridView); 175 ((ViewGroup) rowViewHolder.view).setClipChildren(false); 176 if (rowViewHolder.mContainerViewHolder != null) { 177 ((ViewGroup) rowViewHolder.mContainerViewHolder.view).setClipChildren(false); 178 } 179 } 180 FocusHighlightHelper.setupBrowseItemFocusHighlight(rowViewHolder.mItemBridgeAdapter, mZoomFactor); 181 rowViewHolder.mGridView.setOnChildSelectedListener( 182 new OnChildSelectedListener() { 183 @Override 184 public void onChildSelected(ViewGroup parent, View view, int position, long id) { 185 selectChildView(rowViewHolder, view); 186 } 187 }); 188 rowViewHolder.mItemBridgeAdapter.setAdapterListener( 189 new ItemBridgeAdapter.AdapterListener() { 190 @Override 191 public void onCreate(final ItemBridgeAdapter.ViewHolder viewHolder) { 192 // Only when having an OnItemClickListner, we will attach the OnClickListener. 193 if (getOnItemClickedListener() != null) { 194 viewHolder.mHolder.view.setOnClickListener(new View.OnClickListener() { 195 @Override 196 public void onClick(View v) { 197 ItemBridgeAdapter.ViewHolder ibh = (ItemBridgeAdapter.ViewHolder) 198 rowViewHolder.mGridView.getChildViewHolder(viewHolder.itemView); 199 if (getOnItemClickedListener() != null) { 200 getOnItemClickedListener().onItemClicked(ibh.mItem, 201 (ListRow) rowViewHolder.mRow); 202 } 203 } 204 }); 205 } 206 } 207 208 @Override 209 public void onAttachedToWindow(ItemBridgeAdapter.ViewHolder viewHolder) { 210 if (viewHolder.itemView instanceof ShadowOverlayContainer) { 211 int dimmedColor = rowViewHolder.mColorDimmer.getPaint().getColor(); 212 ((ShadowOverlayContainer) viewHolder.itemView).setOverlayColor(dimmedColor); 213 } 214 viewHolder.itemView.setActivated(rowViewHolder.mExpanded); 215 } 216 }); 217 } 218 219 final boolean needsDefaultListSelectEffect() { 220 return isUsingDefaultListSelectEffect() && getSelectEffectEnabled(); 221 } 222 223 /** 224 * Set {@link PresenterSelector} used for showing a select object in a hover card. 225 */ 226 public final void setHoverCardPresenterSelector(PresenterSelector selector) { 227 mHoverCardPresenterSelector = selector; 228 } 229 230 /** 231 * Get {@link PresenterSelector} used for showing a select object in a hover card. 232 */ 233 public final PresenterSelector getHoverCardPresenterSelector() { 234 return mHoverCardPresenterSelector; 235 } 236 237 /* 238 * Perform operations when a child of horizontal grid view is selected. 239 */ 240 private void selectChildView(ViewHolder rowViewHolder, View view) { 241 ItemBridgeAdapter.ViewHolder ibh = null; 242 if (view != null) { 243 ibh = (ItemBridgeAdapter.ViewHolder) 244 rowViewHolder.mGridView.getChildViewHolder(view); 245 } 246 if (view == null) { 247 if (mHoverCardPresenterSelector != null) { 248 rowViewHolder.mHoverCardViewSwitcher.unselect(); 249 } 250 if (getOnItemSelectedListener() != null) { 251 getOnItemSelectedListener().onItemSelected(null, rowViewHolder.mRow); 252 } 253 } else if (rowViewHolder.mExpanded && rowViewHolder.mSelected) { 254 if (mHoverCardPresenterSelector != null) { 255 rowViewHolder.mHoverCardViewSwitcher.select(rowViewHolder.mGridView, view, 256 ibh.mItem); 257 } 258 if (getOnItemSelectedListener() != null) { 259 getOnItemSelectedListener().onItemSelected(ibh.mItem, rowViewHolder.mRow); 260 } 261 } 262 } 263 264 @Override 265 protected RowPresenter.ViewHolder createRowViewHolder(ViewGroup parent) { 266 ListRowView rowView = new ListRowView(parent.getContext()); 267 setupFadingEffect(rowView); 268 if (mRowHeight != 0) { 269 rowView.getGridView().setRowHeight(mRowHeight); 270 } 271 return new ViewHolder(rowView, rowView.getGridView(), this); 272 } 273 274 @Override 275 protected void onRowViewSelected(RowPresenter.ViewHolder holder, boolean selected) { 276 updateFooterViewSwitcher((ViewHolder) holder); 277 } 278 279 /* 280 * Show or hide hover card when row selection or expanded state is changed. 281 */ 282 private void updateFooterViewSwitcher(ViewHolder vh) { 283 if (vh.mExpanded && vh.mSelected) { 284 if (mHoverCardPresenterSelector != null) { 285 vh.mHoverCardViewSwitcher.init((ViewGroup) vh.view, 286 mHoverCardPresenterSelector); 287 } 288 ItemBridgeAdapter.ViewHolder ibh = (ItemBridgeAdapter.ViewHolder) 289 vh.mGridView.findViewHolderForPosition( 290 vh.mGridView.getSelectedPosition()); 291 selectChildView(vh, ibh == null ? null : ibh.itemView); 292 } else { 293 if (mHoverCardPresenterSelector != null) { 294 vh.mHoverCardViewSwitcher.clear(); 295 } 296 } 297 } 298 299 private void setupFadingEffect(ListRowView rowView) { 300 // content is completely faded at 1/2 padding of left, fading length is 1/2 of padding. 301 HorizontalGridView gridView = rowView.getGridView(); 302 if (mBrowseRowsFadingEdgeLength < 0) { 303 TypedArray ta = gridView.getContext() 304 .obtainStyledAttributes(R.styleable.LeanbackTheme); 305 mBrowseRowsFadingEdgeLength = (int) ta.getDimension( 306 R.styleable.LeanbackTheme_browseRowsFadingEdgeLength, 0); 307 ta.recycle(); 308 } 309 gridView.setFadingLeftEdgeLength(mBrowseRowsFadingEdgeLength); 310 } 311 312 @Override 313 protected void onRowViewExpanded(RowPresenter.ViewHolder holder, boolean expanded) { 314 super.onRowViewExpanded(holder, expanded); 315 ViewHolder vh = (ViewHolder) holder; 316 if (getRowHeight() != getExpandedRowHeight()) { 317 int newHeight = expanded ? getExpandedRowHeight() : getRowHeight(); 318 vh.getGridView().setRowHeight(newHeight); 319 } 320 vh.getGridView().setFadingLeftEdge(!expanded); 321 updateFooterViewSwitcher(vh); 322 } 323 324 @Override 325 protected void onBindRowViewHolder(RowPresenter.ViewHolder holder, Object item) { 326 super.onBindRowViewHolder(holder, item); 327 ViewHolder vh = (ViewHolder) holder; 328 ListRow rowItem = (ListRow) item; 329 vh.mItemBridgeAdapter.clear(); 330 vh.mItemBridgeAdapter.setAdapter(rowItem.getAdapter()); 331 vh.mGridView.setAdapter(vh.mItemBridgeAdapter); 332 } 333 334 @Override 335 protected void onUnbindRowViewHolder(RowPresenter.ViewHolder holder) { 336 ((ViewHolder) holder).mGridView.setAdapter(null); 337 super.onUnbindRowViewHolder(holder); 338 } 339 340 /** 341 * ListRowPresenter overrides the default select effect of {@link RowPresenter} 342 * and return false. 343 */ 344 @Override 345 public final boolean isUsingDefaultSelectEffect() { 346 return false; 347 } 348 349 /** 350 * Returns true so that default select effect is applied to each individual 351 * child of {@link HorizontalGridView}. Subclass may return false to disable 352 * the default implementation. 353 * @see #onSelectLevelChanged(RowPresenter.ViewHolder) 354 */ 355 public boolean isUsingDefaultListSelectEffect() { 356 return true; 357 } 358 359 /** 360 * Returns true if SDK >= 18, where default shadow 361 * is applied to each individual child of {@link HorizontalGridView}. 362 * Subclass may return false to disable. 363 */ 364 public boolean isUsingDefaultShadow() { 365 return ShadowOverlayContainer.supportsShadow(); 366 } 367 368 /** 369 * Enable or disable child shadow. 370 * This is not only for enable/disable default shadow implementation but also subclass must 371 * respect this flag. 372 */ 373 public final void setShadowEnabled(boolean enabled) { 374 mShadowEnabled = enabled; 375 } 376 377 /** 378 * Returns true if child shadow is enabled. 379 * This is not only for enable/disable default shadow implementation but also subclass must 380 * respect this flag. 381 */ 382 public final boolean getShadowEnabled() { 383 return mShadowEnabled; 384 } 385 386 final boolean needsDefaultShadow() { 387 return isUsingDefaultShadow() && getShadowEnabled(); 388 } 389 390 @Override 391 public boolean canDrawOutOfBounds() { 392 return needsDefaultShadow(); 393 } 394 395 /** 396 * Applies select level to header and draw a default color dim over each child 397 * of {@link HorizontalGridView}. 398 * <p> 399 * Subclass may override this method. A subclass 400 * needs to call super.onSelectLevelChanged() for applying header select level 401 * and optionally applying a default select level to each child view of 402 * {@link HorizontalGridView} if {@link #isUsingDefaultListSelectEffect()} 403 * is true. Subclass may override {@link #isUsingDefaultListSelectEffect()} to return 404 * false and deal with the individual item select level by itself. 405 * </p> 406 */ 407 @Override 408 protected void onSelectLevelChanged(RowPresenter.ViewHolder holder) { 409 super.onSelectLevelChanged(holder); 410 if (needsDefaultListSelectEffect()) { 411 ViewHolder vh = (ViewHolder) holder; 412 vh.mColorDimmer.setActiveLevel(holder.mSelectLevel); 413 int dimmedColor = vh.mColorDimmer.getPaint().getColor(); 414 for (int i = 0, count = vh.mGridView.getChildCount(); i < count; i++) { 415 ShadowOverlayContainer wrapper = (ShadowOverlayContainer) vh.mGridView.getChildAt(i); 416 wrapper.setOverlayColor(dimmedColor); 417 } 418 if (vh.mGridView.getFadingLeftEdge()) { 419 vh.mGridView.invalidate(); 420 } 421 } 422 } 423 424} 425