ListRowPresenter.java revision 9240e796bc63422c28f2707840bd99c48573279b
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 PresenterSelector mHoverCardPresenterSelector; 80 private int mZoomFactor; 81 private boolean mShadowEnabled = true; 82 private int mBrowseRowsFadingEdgeLength = -1; 83 84 /** 85 * Constructs a ListRowPresenter with defaults. 86 * Uses {@link FocusHighlight#ZOOM_FACTOR_MEDIUM} for focus zooming. 87 */ 88 public ListRowPresenter() { 89 this(FocusHighlight.ZOOM_FACTOR_MEDIUM); 90 } 91 92 /** 93 * Constructs a ListRowPresenter with the given parameters. 94 * 95 * @param zoomFactor Controls the zoom factor used when an item view is focused. One of 96 * {@link FocusHighlight#ZOOM_FACTOR_NONE}, 97 * {@link FocusHighlight#ZOOM_FACTOR_SMALL}, 98 * {@link FocusHighlight#ZOOM_FACTOR_MEDIUM}, 99 * {@link FocusHighlight#ZOOM_FACTOR_LARGE} 100 */ 101 public ListRowPresenter(int zoomFactor) { 102 mZoomFactor = zoomFactor; 103 } 104 105 /** 106 * Returns the zoom factor used for focus highlighting. 107 */ 108 public final int getZoomFactor() { 109 return mZoomFactor; 110 } 111 112 private ItemBridgeAdapter.Wrapper mCardWrapper = new ItemBridgeAdapter.Wrapper() { 113 @Override 114 public View createWrapper(View root) { 115 ShadowOverlayContainer wrapper = new ShadowOverlayContainer(root.getContext()); 116 wrapper.setLayoutParams( 117 new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT)); 118 wrapper.initialize(needsDefaultShadow(), needsDefaultListSelectEffect()); 119 return wrapper; 120 } 121 @Override 122 public void wrap(View wrapper, View wrapped) { 123 ((ShadowOverlayContainer) wrapper).wrap(wrapped); 124 } 125 }; 126 127 @Override 128 protected void initializeRowViewHolder(RowPresenter.ViewHolder holder) { 129 super.initializeRowViewHolder(holder); 130 final ViewHolder rowViewHolder = (ViewHolder) holder; 131 if (needsDefaultListSelectEffect() || needsDefaultShadow()) { 132 rowViewHolder.mItemBridgeAdapter.setWrapper(mCardWrapper); 133 } 134 if (needsDefaultListSelectEffect()) { 135 ShadowOverlayContainer.prepareParentForShadow(rowViewHolder.mGridView); 136 ((ViewGroup) rowViewHolder.view).setClipChildren(false); 137 if (rowViewHolder.mContainerViewHolder != null) { 138 ((ViewGroup) rowViewHolder.mContainerViewHolder.view).setClipChildren(false); 139 } 140 } 141 FocusHighlightHelper.setupBrowseItemFocusHighlight(rowViewHolder.mItemBridgeAdapter, mZoomFactor); 142 rowViewHolder.mGridView.setOnChildSelectedListener( 143 new OnChildSelectedListener() { 144 @Override 145 public void onChildSelected(ViewGroup parent, View view, int position, long id) { 146 selectChildView(rowViewHolder, view); 147 } 148 }); 149 rowViewHolder.mItemBridgeAdapter.setAdapterListener( 150 new ItemBridgeAdapter.AdapterListener() { 151 @Override 152 public void onCreate(final ItemBridgeAdapter.ViewHolder viewHolder) { 153 // Only when having an OnItemClickListner, we will attach the OnClickListener. 154 if (getOnItemClickedListener() != null) { 155 viewHolder.mHolder.view.setOnClickListener(new View.OnClickListener() { 156 @Override 157 public void onClick(View v) { 158 ItemBridgeAdapter.ViewHolder ibh = (ItemBridgeAdapter.ViewHolder) 159 rowViewHolder.mGridView.getChildViewHolder(viewHolder.itemView); 160 if (getOnItemClickedListener() != null) { 161 getOnItemClickedListener().onItemClicked(ibh.mItem, 162 (ListRow) rowViewHolder.mRow); 163 } 164 } 165 }); 166 } 167 } 168 169 @Override 170 public void onAttachedToWindow(ItemBridgeAdapter.ViewHolder viewHolder) { 171 if (viewHolder.itemView instanceof ShadowOverlayContainer) { 172 int dimmedColor = rowViewHolder.mColorDimmer.getPaint().getColor(); 173 ((ShadowOverlayContainer) viewHolder.itemView).setOverlayColor(dimmedColor); 174 } 175 } 176 }); 177 } 178 179 final boolean needsDefaultListSelectEffect() { 180 return isUsingDefaultListSelectEffect() && getSelectEffectEnabled(); 181 } 182 183 /** 184 * Set {@link PresenterSelector} used for showing a select object in a hover card. 185 */ 186 public final void setHoverCardPresenterSelector(PresenterSelector selector) { 187 mHoverCardPresenterSelector = selector; 188 } 189 190 /** 191 * Get {@link PresenterSelector} used for showing a select object in a hover card. 192 */ 193 public final PresenterSelector getHoverCardPresenterSelector() { 194 return mHoverCardPresenterSelector; 195 } 196 197 /* 198 * Perform operations when a child of horizontal grid view is selected. 199 */ 200 private void selectChildView(ViewHolder rowViewHolder, View view) { 201 ItemBridgeAdapter.ViewHolder ibh = null; 202 if (view != null) { 203 ibh = (ItemBridgeAdapter.ViewHolder) 204 rowViewHolder.mGridView.getChildViewHolder(view); 205 } 206 if (view == null) { 207 if (mHoverCardPresenterSelector != null) { 208 rowViewHolder.mHoverCardViewSwitcher.unselect(); 209 } 210 if (getOnItemSelectedListener() != null) { 211 getOnItemSelectedListener().onItemSelected(null, rowViewHolder.mRow); 212 } 213 } else if (rowViewHolder.mExpanded && rowViewHolder.mSelected) { 214 if (mHoverCardPresenterSelector != null) { 215 rowViewHolder.mHoverCardViewSwitcher.select(rowViewHolder.mGridView, view, 216 ibh.mItem); 217 } 218 if (getOnItemSelectedListener() != null) { 219 getOnItemSelectedListener().onItemSelected(ibh.mItem, rowViewHolder.mRow); 220 } 221 } 222 } 223 224 @Override 225 protected RowPresenter.ViewHolder createRowViewHolder(ViewGroup parent) { 226 ListRowView rowView = new ListRowView(parent.getContext()); 227 setupFadingEffect(rowView); 228 return new ViewHolder(rowView, rowView.getGridView(), this); 229 } 230 231 @Override 232 protected void onRowViewSelected(RowPresenter.ViewHolder holder, boolean selected) { 233 updateFooterViewSwitcher((ViewHolder) holder); 234 } 235 236 /* 237 * Show or hide hover card when row selection or expanded state is changed. 238 */ 239 private void updateFooterViewSwitcher(ViewHolder vh) { 240 if (vh.mExpanded && vh.mSelected) { 241 if (mHoverCardPresenterSelector != null) { 242 vh.mHoverCardViewSwitcher.init((ViewGroup) vh.view, 243 mHoverCardPresenterSelector); 244 ItemBridgeAdapter.ViewHolder ibh = (ItemBridgeAdapter.ViewHolder) 245 vh.mGridView.findViewHolderForPosition( 246 vh.mGridView.getSelectedPosition()); 247 selectChildView(vh, ibh == null ? null : ibh.itemView); 248 } 249 } else { 250 if (mHoverCardPresenterSelector != null) { 251 vh.mHoverCardViewSwitcher.clear(); 252 } 253 } 254 } 255 256 private void setupFadingEffect(ListRowView rowView) { 257 // content is completely faded at 1/2 padding of left, fading length is 1/2 of padding. 258 HorizontalGridView gridView = rowView.getGridView(); 259 if (mBrowseRowsFadingEdgeLength < 0) { 260 TypedArray ta = gridView.getContext() 261 .obtainStyledAttributes(R.styleable.LeanbackTheme); 262 mBrowseRowsFadingEdgeLength = (int) ta.getDimension( 263 R.styleable.LeanbackTheme_browseRowsFadingEdgeLength, 0); 264 ta.recycle(); 265 } 266 gridView.setFadingLeftEdgeLength(mBrowseRowsFadingEdgeLength); 267 } 268 269 @Override 270 protected void onRowViewExpanded(RowPresenter.ViewHolder holder, boolean expanded) { 271 super.onRowViewExpanded(holder, expanded); 272 ViewHolder vh = (ViewHolder) holder; 273 vh.getGridView().setFadingLeftEdge(!expanded); 274 updateFooterViewSwitcher(vh); 275 } 276 277 @Override 278 protected void onBindRowViewHolder(RowPresenter.ViewHolder holder, Object item) { 279 super.onBindRowViewHolder(holder, item); 280 ViewHolder vh = (ViewHolder) holder; 281 ListRow rowItem = (ListRow) item; 282 vh.mItemBridgeAdapter.clear(); 283 vh.mItemBridgeAdapter.setAdapter(rowItem.getAdapter()); 284 vh.mGridView.setAdapter(vh.mItemBridgeAdapter); 285 } 286 287 @Override 288 protected void onUnbindRowViewHolder(RowPresenter.ViewHolder holder) { 289 ((ViewHolder) holder).mGridView.setAdapter(null); 290 super.onUnbindRowViewHolder(holder); 291 } 292 293 /** 294 * ListRowPresenter overrides the default select effect of {@link RowPresenter} 295 * and return false. 296 */ 297 @Override 298 public final boolean isUsingDefaultSelectEffect() { 299 return false; 300 } 301 302 /** 303 * Returns true so that default select effect is applied to each individual 304 * child of {@link HorizontalGridView}. Subclass may return false to disable 305 * the default implementation. 306 * @see #onSelectLevelChanged(RowPresenter.ViewHolder) 307 */ 308 public boolean isUsingDefaultListSelectEffect() { 309 return true; 310 } 311 312 /** 313 * Returns true if SDK >= 18, where default shadow 314 * is applied to each individual child of {@link HorizontalGridView}. 315 * Subclass may return false to disable. 316 */ 317 public boolean isUsingDefaultShadow() { 318 return ShadowOverlayContainer.supportsShadow(); 319 } 320 321 /** 322 * Enable or disable child shadow. 323 * This is not only for enable/disable default shadow implementation but also subclass must 324 * respect this flag. 325 */ 326 public final void setShadowEnabled(boolean enabled) { 327 mShadowEnabled = enabled; 328 } 329 330 /** 331 * Returns true if child shadow is enabled. 332 * This is not only for enable/disable default shadow implementation but also subclass must 333 * respect this flag. 334 */ 335 public final boolean getShadowEnabled() { 336 return mShadowEnabled; 337 } 338 339 final boolean needsDefaultShadow() { 340 return isUsingDefaultShadow() && getShadowEnabled(); 341 } 342 343 @Override 344 public boolean canDrawOutOfBounds() { 345 return needsDefaultShadow(); 346 } 347 348 /** 349 * Applies select level to header and draw a default color dim over each child 350 * of {@link HorizontalGridView}. 351 * <p> 352 * Subclass may override this method. A subclass 353 * needs to call super.onSelectLevelChanged() for applying header select level 354 * and optionally applying a default select level to each child view of 355 * {@link HorizontalGridView} if {@link #isUsingDefaultListSelectEffect()} 356 * is true. Subclass may override {@link #isUsingDefaultListSelectEffect()} to return 357 * false and deal with the individual item select level by itself. 358 * </p> 359 */ 360 @Override 361 protected void onSelectLevelChanged(RowPresenter.ViewHolder holder) { 362 super.onSelectLevelChanged(holder); 363 if (needsDefaultListSelectEffect()) { 364 ViewHolder vh = (ViewHolder) holder; 365 vh.mColorDimmer.setActiveLevel(holder.mSelectLevel); 366 int dimmedColor = vh.mColorDimmer.getPaint().getColor(); 367 for (int i = 0, count = vh.mGridView.getChildCount(); i < count; i++) { 368 ShadowOverlayContainer wrapper = (ShadowOverlayContainer) vh.mGridView.getChildAt(i); 369 wrapper.setOverlayColor(dimmedColor); 370 } 371 if (vh.mGridView.getFadingLeftEdge()) { 372 vh.mGridView.invalidate(); 373 } 374 } 375 } 376 377} 378