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.app;
15
16import java.util.ArrayList;
17
18import android.animation.TimeAnimator;
19import android.animation.TimeAnimator.TimeListener;
20import android.os.Bundle;
21import android.support.v17.leanback.R;
22import android.support.v17.leanback.widget.ItemBridgeAdapter;
23import android.support.v17.leanback.widget.OnItemViewClickedListener;
24import android.support.v17.leanback.widget.OnItemViewSelectedListener;
25import android.support.v17.leanback.widget.RowPresenter.ViewHolder;
26import android.support.v17.leanback.widget.ScaleFrameLayout;
27import android.support.v17.leanback.widget.VerticalGridView;
28import android.support.v17.leanback.widget.HorizontalGridView;
29import android.support.v17.leanback.widget.RowPresenter;
30import android.support.v17.leanback.widget.ListRowPresenter;
31import android.support.v17.leanback.widget.Presenter;
32import android.support.v7.widget.RecyclerView;
33import android.util.Log;
34import android.view.LayoutInflater;
35import android.view.View;
36import android.view.ViewGroup;
37import android.view.ViewTreeObserver;
38import android.view.animation.DecelerateInterpolator;
39import android.view.animation.Interpolator;
40
41/**
42 * An ordered set of rows of leanback widgets.
43 * <p>
44 * A RowsFragment renders the elements of its
45 * {@link android.support.v17.leanback.widget.ObjectAdapter} as a set
46 * of rows in a vertical list. The elements in this adapter must be subclasses
47 * of {@link android.support.v17.leanback.widget.Row}.
48 * </p>
49 */
50public class RowsFragment extends BaseRowFragment {
51
52    /**
53     * Internal helper class that manages row select animation and apply a default
54     * dim to each row.
55     */
56    final class RowViewHolderExtra implements TimeListener {
57        final RowPresenter mRowPresenter;
58        final Presenter.ViewHolder mRowViewHolder;
59
60        final TimeAnimator mSelectAnimator = new TimeAnimator();
61
62        int mSelectAnimatorDurationInUse;
63        Interpolator mSelectAnimatorInterpolatorInUse;
64        float mSelectLevelAnimStart;
65        float mSelectLevelAnimDelta;
66
67        RowViewHolderExtra(ItemBridgeAdapter.ViewHolder ibvh) {
68            mRowPresenter = (RowPresenter) ibvh.getPresenter();
69            mRowViewHolder = ibvh.getViewHolder();
70            mSelectAnimator.setTimeListener(this);
71        }
72
73        @Override
74        public void onTimeUpdate(TimeAnimator animation, long totalTime, long deltaTime) {
75            if (mSelectAnimator.isRunning()) {
76                updateSelect(totalTime, deltaTime);
77            }
78        }
79
80        void updateSelect(long totalTime, long deltaTime) {
81            float fraction;
82            if (totalTime >= mSelectAnimatorDurationInUse) {
83                fraction = 1;
84                mSelectAnimator.end();
85            } else {
86                fraction = (float) (totalTime / (double) mSelectAnimatorDurationInUse);
87            }
88            if (mSelectAnimatorInterpolatorInUse != null) {
89                fraction = mSelectAnimatorInterpolatorInUse.getInterpolation(fraction);
90            }
91            float level =  mSelectLevelAnimStart + fraction * mSelectLevelAnimDelta;
92            mRowPresenter.setSelectLevel(mRowViewHolder, level);
93        }
94
95        void animateSelect(boolean select, boolean immediate) {
96            mSelectAnimator.end();
97            final float end = select ? 1 : 0;
98            if (immediate) {
99                mRowPresenter.setSelectLevel(mRowViewHolder, end);
100            } else if (mRowPresenter.getSelectLevel(mRowViewHolder) != end) {
101                mSelectAnimatorDurationInUse = mSelectAnimatorDuration;
102                mSelectAnimatorInterpolatorInUse = mSelectAnimatorInterpolator;
103                mSelectLevelAnimStart = mRowPresenter.getSelectLevel(mRowViewHolder);
104                mSelectLevelAnimDelta = end - mSelectLevelAnimStart;
105                mSelectAnimator.start();
106            }
107        }
108
109    }
110
111    private static final String TAG = "RowsFragment";
112    private static final boolean DEBUG = false;
113
114    private ItemBridgeAdapter.ViewHolder mSelectedViewHolder;
115    private int mSubPosition;
116    private boolean mExpand = true;
117    private boolean mViewsCreated;
118    private float mRowScaleFactor;
119    private int mAlignedTop;
120    private boolean mRowScaleEnabled;
121    private ScaleFrameLayout mScaleFrameLayout;
122    private boolean mAfterEntranceTransition = true;
123
124    private OnItemViewSelectedListener mOnItemViewSelectedListener;
125    private OnItemViewClickedListener mOnItemViewClickedListener;
126
127    // Select animation and interpolator are not intended to be
128    // exposed at this moment. They might be synced with vertical scroll
129    // animation later.
130    int mSelectAnimatorDuration;
131    Interpolator mSelectAnimatorInterpolator = new DecelerateInterpolator(2);
132
133    private RecyclerView.RecycledViewPool mRecycledViewPool;
134    private ArrayList<Presenter> mPresenterMapper;
135
136    private ItemBridgeAdapter.AdapterListener mExternalAdapterListener;
137
138    @Override
139    protected VerticalGridView findGridViewFromRoot(View view) {
140        return (VerticalGridView) view.findViewById(R.id.container_list);
141    }
142
143    /**
144     * Sets an item clicked listener on the fragment.
145     * OnItemViewClickedListener will override {@link View.OnClickListener} that
146     * item presenter sets during {@link Presenter#onCreateViewHolder(ViewGroup)}.
147     * So in general,  developer should choose one of the listeners but not both.
148     */
149    public void setOnItemViewClickedListener(OnItemViewClickedListener listener) {
150        mOnItemViewClickedListener = listener;
151        if (mViewsCreated) {
152            throw new IllegalStateException(
153                    "Item clicked listener must be set before views are created");
154        }
155    }
156
157    /**
158     * Returns the item clicked listener.
159     */
160    public OnItemViewClickedListener getOnItemViewClickedListener() {
161        return mOnItemViewClickedListener;
162    }
163
164    /**
165     * Set the visibility of titles/hovercard of browse rows.
166     */
167    public void setExpand(boolean expand) {
168        mExpand = expand;
169        VerticalGridView listView = getVerticalGridView();
170        if (listView != null) {
171            updateRowScaling();
172            final int count = listView.getChildCount();
173            if (DEBUG) Log.v(TAG, "setExpand " + expand + " count " + count);
174            for (int i = 0; i < count; i++) {
175                View view = listView.getChildAt(i);
176                ItemBridgeAdapter.ViewHolder vh = (ItemBridgeAdapter.ViewHolder) listView.getChildViewHolder(view);
177                setRowViewExpanded(vh, mExpand);
178            }
179        }
180    }
181
182    /**
183     * Sets an item selection listener.
184     */
185    public void setOnItemViewSelectedListener(OnItemViewSelectedListener listener) {
186        mOnItemViewSelectedListener = listener;
187        VerticalGridView listView = getVerticalGridView();
188        if (listView != null) {
189            final int count = listView.getChildCount();
190            for (int i = 0; i < count; i++) {
191                View view = listView.getChildAt(i);
192                ItemBridgeAdapter.ViewHolder ibvh = (ItemBridgeAdapter.ViewHolder)
193                        listView.getChildViewHolder(view);
194                RowPresenter rowPresenter = (RowPresenter) ibvh.getPresenter();
195                RowPresenter.ViewHolder vh = rowPresenter.getRowViewHolder(ibvh.getViewHolder());
196                vh.setOnItemViewSelectedListener(mOnItemViewSelectedListener);
197            }
198        }
199    }
200
201    /**
202     * Returns an item selection listener.
203     */
204    public OnItemViewSelectedListener getOnItemViewSelectedListener() {
205        return mOnItemViewSelectedListener;
206    }
207
208    /**
209     * Enables scaling of rows.
210     *
211     * @param enable true to enable row scaling
212     */
213    public void enableRowScaling(boolean enable) {
214        mRowScaleEnabled = enable;
215    }
216
217    @Override
218    void onRowSelected(RecyclerView parent, RecyclerView.ViewHolder viewHolder,
219            int position, int subposition) {
220        if (mSelectedViewHolder != viewHolder || mSubPosition != subposition) {
221            if (DEBUG) Log.v(TAG, "new row selected position " + position + " subposition "
222                    + subposition + " view " + viewHolder.itemView);
223            mSubPosition = subposition;
224            if (mSelectedViewHolder != null) {
225                setRowViewSelected(mSelectedViewHolder, false, false);
226            }
227            mSelectedViewHolder = (ItemBridgeAdapter.ViewHolder) viewHolder;
228            if (mSelectedViewHolder != null) {
229                setRowViewSelected(mSelectedViewHolder, true, false);
230            }
231        }
232    }
233
234    @Override
235    int getLayoutResourceId() {
236        return R.layout.lb_rows_fragment;
237    }
238
239    @Override
240    public void onCreate(Bundle savedInstanceState) {
241        super.onCreate(savedInstanceState);
242        mSelectAnimatorDuration = getResources().getInteger(
243                R.integer.lb_browse_rows_anim_duration);
244        mRowScaleFactor = getResources().getFraction(
245                R.fraction.lb_browse_rows_scale, 1, 1);
246    }
247
248    @Override
249    public View onCreateView(LayoutInflater inflater, ViewGroup container,
250            Bundle savedInstanceState) {
251        View view = super.onCreateView(inflater, container, savedInstanceState);
252        mScaleFrameLayout = (ScaleFrameLayout) view.findViewById(R.id.scale_frame);
253        return view;
254    }
255
256    @Override
257    public void onViewCreated(View view, Bundle savedInstanceState) {
258        if (DEBUG) Log.v(TAG, "onViewCreated");
259        super.onViewCreated(view, savedInstanceState);
260        // Align the top edge of child with id row_content.
261        // Need set this for directly using RowsFragment.
262        getVerticalGridView().setItemAlignmentViewId(R.id.row_content);
263        getVerticalGridView().setSaveChildrenPolicy(VerticalGridView.SAVE_LIMITED_CHILD);
264
265        mRecycledViewPool = null;
266        mPresenterMapper = null;
267    }
268
269    @Override
270    public void onDestroyView() {
271        mViewsCreated = false;
272        super.onDestroyView();
273    }
274
275    @Override
276    void setItemAlignment() {
277        super.setItemAlignment();
278        if (getVerticalGridView() != null) {
279            getVerticalGridView().setItemAlignmentOffsetWithPadding(true);
280        }
281    }
282
283    void setExternalAdapterListener(ItemBridgeAdapter.AdapterListener listener) {
284        mExternalAdapterListener = listener;
285    }
286
287    /**
288     * Returns the view that will change scale.
289     */
290    View getScaleView() {
291        return getVerticalGridView();
292    }
293
294    /**
295     * Sets the pivots to scale rows fragment.
296     */
297    void setScalePivots(float pivotX, float pivotY) {
298        // set pivot on ScaleFrameLayout, it will be propagated to its child VerticalGridView
299        // where we actually change scale.
300        mScaleFrameLayout.setPivotX(pivotX);
301        mScaleFrameLayout.setPivotY(pivotY);
302    }
303
304    private static void setRowViewExpanded(ItemBridgeAdapter.ViewHolder vh, boolean expanded) {
305        ((RowPresenter) vh.getPresenter()).setRowViewExpanded(vh.getViewHolder(), expanded);
306    }
307
308    private static void setRowViewSelected(ItemBridgeAdapter.ViewHolder vh, boolean selected,
309            boolean immediate) {
310        RowViewHolderExtra extra = (RowViewHolderExtra) vh.getExtraObject();
311        extra.animateSelect(selected, immediate);
312        ((RowPresenter) vh.getPresenter()).setRowViewSelected(vh.getViewHolder(), selected);
313    }
314
315    private final ItemBridgeAdapter.AdapterListener mBridgeAdapterListener =
316            new ItemBridgeAdapter.AdapterListener() {
317        @Override
318        public void onAddPresenter(Presenter presenter, int type) {
319            if (mExternalAdapterListener != null) {
320                mExternalAdapterListener.onAddPresenter(presenter, type);
321            }
322        }
323        @Override
324        public void onCreate(ItemBridgeAdapter.ViewHolder vh) {
325            VerticalGridView listView = getVerticalGridView();
326            if (listView != null) {
327                // set clip children false for slide animation
328                listView.setClipChildren(false);
329            }
330            setupSharedViewPool(vh);
331            mViewsCreated = true;
332            vh.setExtraObject(new RowViewHolderExtra(vh));
333            // selected state is initialized to false, then driven by grid view onChildSelected
334            // events.  When there is rebind, grid view fires onChildSelected event properly.
335            // So we don't need do anything special later in onBind or onAttachedToWindow.
336            setRowViewSelected(vh, false, true);
337            if (mExternalAdapterListener != null) {
338                mExternalAdapterListener.onCreate(vh);
339            }
340        }
341        @Override
342        public void onAttachedToWindow(ItemBridgeAdapter.ViewHolder vh) {
343            if (DEBUG) Log.v(TAG, "onAttachToWindow");
344            // All views share the same mExpand value.  When we attach a view to grid view,
345            // we should make sure it pick up the latest mExpand value we set early on other
346            // attached views.  For no-structure-change update,  the view is rebound to new data,
347            // but again it should use the unchanged mExpand value,  so we don't need do any
348            // thing in onBind.
349            setRowViewExpanded(vh, mExpand);
350            RowPresenter rowPresenter = (RowPresenter) vh.getPresenter();
351            RowPresenter.ViewHolder rowVh = rowPresenter.getRowViewHolder(vh.getViewHolder());
352            rowVh.setOnItemViewSelectedListener(mOnItemViewSelectedListener);
353            rowVh.setOnItemViewClickedListener(mOnItemViewClickedListener);
354            rowPresenter.setEntranceTransitionState(rowVh, mAfterEntranceTransition);
355            if (mExternalAdapterListener != null) {
356                mExternalAdapterListener.onAttachedToWindow(vh);
357            }
358        }
359        @Override
360        public void onDetachedFromWindow(ItemBridgeAdapter.ViewHolder vh) {
361            if (mSelectedViewHolder == vh) {
362                setRowViewSelected(mSelectedViewHolder, false, true);
363                mSelectedViewHolder = null;
364            }
365            if (mExternalAdapterListener != null) {
366                mExternalAdapterListener.onDetachedFromWindow(vh);
367            }
368        }
369        @Override
370        public void onBind(ItemBridgeAdapter.ViewHolder vh) {
371            if (mExternalAdapterListener != null) {
372                mExternalAdapterListener.onBind(vh);
373            }
374        }
375        @Override
376        public void onUnbind(ItemBridgeAdapter.ViewHolder vh) {
377            setRowViewSelected(vh, false, true);
378            if (mExternalAdapterListener != null) {
379                mExternalAdapterListener.onUnbind(vh);
380            }
381        }
382    };
383
384    private void setupSharedViewPool(ItemBridgeAdapter.ViewHolder bridgeVh) {
385        RowPresenter rowPresenter = (RowPresenter) bridgeVh.getPresenter();
386        RowPresenter.ViewHolder rowVh = rowPresenter.getRowViewHolder(bridgeVh.getViewHolder());
387
388        if (rowVh instanceof ListRowPresenter.ViewHolder) {
389            HorizontalGridView view = ((ListRowPresenter.ViewHolder) rowVh).getGridView();
390            // Recycled view pool is shared between all list rows
391            if (mRecycledViewPool == null) {
392                mRecycledViewPool = view.getRecycledViewPool();
393            } else {
394                view.setRecycledViewPool(mRecycledViewPool);
395            }
396
397            ItemBridgeAdapter bridgeAdapter =
398                    ((ListRowPresenter.ViewHolder) rowVh).getBridgeAdapter();
399            if (mPresenterMapper == null) {
400                mPresenterMapper = bridgeAdapter.getPresenterMapper();
401            } else {
402                bridgeAdapter.setPresenterMapper(mPresenterMapper);
403            }
404        }
405    }
406
407    @Override
408    void updateAdapter() {
409        super.updateAdapter();
410        mSelectedViewHolder = null;
411        mViewsCreated = false;
412
413        ItemBridgeAdapter adapter = getBridgeAdapter();
414        if (adapter != null) {
415            adapter.setAdapterListener(mBridgeAdapterListener);
416        }
417    }
418
419    @Override
420    boolean onTransitionPrepare() {
421        boolean prepared = super.onTransitionPrepare();
422        if (prepared) {
423            freezeRows(true);
424        }
425        return prepared;
426    }
427
428    class ExpandPreLayout implements ViewTreeObserver.OnPreDrawListener {
429
430        final View mVerticalView;
431        final Runnable mCallback;
432        int mState;
433
434        final static int STATE_INIT = 0;
435        final static int STATE_FIRST_DRAW = 1;
436        final static int STATE_SECOND_DRAW = 2;
437
438        ExpandPreLayout(Runnable callback) {
439            mVerticalView = getVerticalGridView();
440            mCallback = callback;
441        }
442
443        void execute() {
444            mVerticalView.getViewTreeObserver().addOnPreDrawListener(this);
445            setExpand(false);
446            mState = STATE_INIT;
447        }
448
449        @Override
450        public boolean onPreDraw() {
451            if (mState == STATE_INIT) {
452                setExpand(true);
453                mState = STATE_FIRST_DRAW;
454            } else if (mState == STATE_FIRST_DRAW) {
455                mCallback.run();
456                mVerticalView.getViewTreeObserver().removeOnPreDrawListener(this);
457                mState = STATE_SECOND_DRAW;
458            }
459            return false;
460        }
461    }
462
463    void onExpandTransitionStart(boolean expand, final Runnable callback) {
464        onTransitionPrepare();
465        onTransitionStart();
466        if (expand) {
467            callback.run();
468            return;
469        }
470        // Run a "pre" layout when we go non-expand, in order to get the initial
471        // positions of added rows.
472        new ExpandPreLayout(callback).execute();
473    }
474
475    private boolean needsScale() {
476        return mRowScaleEnabled && !mExpand;
477    }
478
479    private void updateRowScaling() {
480        final float scaleFactor = needsScale() ? mRowScaleFactor : 1f;
481        mScaleFrameLayout.setLayoutScaleY(scaleFactor);
482        getScaleView().setScaleY(scaleFactor);
483        getScaleView().setScaleX(scaleFactor);
484        updateWindowAlignOffset();
485    }
486
487    private void updateWindowAlignOffset() {
488        int alignOffset = mAlignedTop;
489        if (needsScale()) {
490            alignOffset = (int) (alignOffset / mRowScaleFactor + 0.5f);
491        }
492        getVerticalGridView().setWindowAlignmentOffset(alignOffset);
493    }
494
495    @Override
496    void setWindowAlignmentFromTop(int alignedTop) {
497        mAlignedTop = alignedTop;
498        final VerticalGridView gridView = getVerticalGridView();
499        if (gridView != null) {
500            updateWindowAlignOffset();
501            // align to a fixed position from top
502            gridView.setWindowAlignmentOffsetPercent(
503                    VerticalGridView.WINDOW_ALIGN_OFFSET_PERCENT_DISABLED);
504            gridView.setWindowAlignment(VerticalGridView.WINDOW_ALIGN_NO_EDGE);
505        }
506    }
507
508    @Override
509    void onTransitionEnd() {
510        super.onTransitionEnd();
511        freezeRows(false);
512    }
513
514    private void freezeRows(boolean freeze) {
515        VerticalGridView verticalView = getVerticalGridView();
516        if (verticalView != null) {
517            final int count = verticalView.getChildCount();
518            for (int i = 0; i < count; i++) {
519                ItemBridgeAdapter.ViewHolder ibvh = (ItemBridgeAdapter.ViewHolder)
520                    verticalView.getChildViewHolder(verticalView.getChildAt(i));
521                RowPresenter rowPresenter = (RowPresenter) ibvh.getPresenter();
522                RowPresenter.ViewHolder vh = rowPresenter.getRowViewHolder(ibvh.getViewHolder());
523                rowPresenter.freeze(vh, freeze);
524            }
525        }
526    }
527
528    /**
529     * For rows that willing to participate entrance transition,  this function
530     * hide views if afterTransition is true,  show views if afterTransition is false.
531     */
532    void setEntranceTransitionState(boolean afterTransition) {
533        mAfterEntranceTransition = afterTransition;
534        VerticalGridView verticalView = getVerticalGridView();
535        if (verticalView != null) {
536            final int count = verticalView.getChildCount();
537            for (int i = 0; i < count; i++) {
538                ItemBridgeAdapter.ViewHolder ibvh = (ItemBridgeAdapter.ViewHolder)
539                    verticalView.getChildViewHolder(verticalView.getChildAt(i));
540                RowPresenter rowPresenter = (RowPresenter) ibvh.getPresenter();
541                RowPresenter.ViewHolder vh = rowPresenter.getRowViewHolder(ibvh.getViewHolder());
542                rowPresenter.setEntranceTransitionState(vh, mAfterEntranceTransition);
543            }
544        }
545    }
546}
547