HeadersSupportFragment.java revision 61905b0b52c50018dcaebcd79699c39b8f28d622 
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 */
14
15package android.support.v17.leanback.app;
16
17import android.content.Context;
18import android.graphics.Color;
19import android.graphics.drawable.Drawable;
20import android.graphics.drawable.GradientDrawable;
21import android.os.Bundle;
22import android.support.v17.leanback.R;
23import android.support.v17.leanback.widget.FocusHighlightHelper;
24import android.support.v17.leanback.widget.ItemBridgeAdapter;
25import android.support.v17.leanback.widget.PresenterSelector;
26import android.support.v17.leanback.widget.OnItemSelectedListener;
27import android.support.v17.leanback.widget.Row;
28import android.support.v17.leanback.widget.RowHeaderPresenter;
29import android.support.v17.leanback.widget.SinglePresenterSelector;
30import android.support.v17.leanback.widget.VerticalGridView;
31import android.util.TypedValue;
32import android.view.View;
33import android.view.ViewGroup;
34import android.view.View.OnLayoutChangeListener;
35import android.widget.FrameLayout;
36
37/**
38 * An internal fragment containing a list of row headers.
39 */
40public class HeadersSupportFragment extends BaseRowSupportFragment {
41
42    interface OnHeaderClickedListener {
43        void onHeaderClicked();
44    }
45
46    private OnItemSelectedListener mOnItemSelectedListener;
47    private OnHeaderClickedListener mOnHeaderClickedListener;
48    private boolean mHeadersEnabled = true;
49    private boolean mHeadersGone = false;
50    private int mBackgroundColor;
51    private boolean mBackgroundColorSet;
52
53    private static final PresenterSelector sHeaderPresenter = new SinglePresenterSelector(
54            new RowHeaderPresenter(R.layout.lb_header));
55
56    public HeadersSupportFragment() {
57        setPresenterSelector(sHeaderPresenter);
58    }
59
60    public void setOnHeaderClickedListener(OnHeaderClickedListener listener) {
61        mOnHeaderClickedListener = listener;
62    }
63
64    public void setOnItemSelectedListener(OnItemSelectedListener listener) {
65        mOnItemSelectedListener = listener;
66    }
67
68    @Override
69    protected VerticalGridView findGridViewFromRoot(View view) {
70        return (VerticalGridView) view.findViewById(R.id.browse_headers);
71    }
72
73    @Override
74    protected void onRowSelected(ViewGroup parent, View view, int position, long id) {
75        if (mOnItemSelectedListener != null) {
76            if (position >= 0) {
77                Row row = (Row) getAdapter().get(position);
78                mOnItemSelectedListener.onItemSelected(null, row);
79            } else {
80                mOnItemSelectedListener.onItemSelected(null, null);
81            }
82        }
83    }
84
85    private final ItemBridgeAdapter.AdapterListener mAdapterListener =
86            new ItemBridgeAdapter.AdapterListener() {
87        @Override
88        public void onCreate(ItemBridgeAdapter.ViewHolder viewHolder) {
89            View headerView = viewHolder.getViewHolder().view;
90            headerView.setOnClickListener(new View.OnClickListener() {
91                @Override
92                public void onClick(View v) {
93                    if (mOnHeaderClickedListener != null) {
94                        mOnHeaderClickedListener.onHeaderClicked();
95                    }
96                }
97            });
98            headerView.setFocusable(true);
99            headerView.setFocusableInTouchMode(true);
100            if (mWrapper != null) {
101                viewHolder.itemView.addOnLayoutChangeListener(sLayoutChangeListener);
102            } else {
103                headerView.addOnLayoutChangeListener(sLayoutChangeListener);
104            }
105        }
106
107    };
108
109    private static OnLayoutChangeListener sLayoutChangeListener = new OnLayoutChangeListener() {
110        @Override
111        public void onLayoutChange(View v, int left, int top, int right, int bottom,
112            int oldLeft, int oldTop, int oldRight, int oldBottom) {
113            v.setPivotX(0);
114            v.setPivotY(v.getMeasuredHeight() / 2);
115        }
116    };
117
118    @Override
119    protected int getLayoutResourceId() {
120        return R.layout.lb_headers_fragment;
121    }
122
123    @Override
124    public void onViewCreated(View view, Bundle savedInstanceState) {
125        super.onViewCreated(view, savedInstanceState);
126        final VerticalGridView listView = getVerticalGridView();
127        if (listView == null) {
128            return;
129        }
130        if (getBridgeAdapter() != null) {
131            FocusHighlightHelper.setupHeaderItemFocusHighlight(listView);
132        }
133        view.setBackgroundColor(getBackgroundColor());
134        updateFadingEdgeToBrandColor(getBackgroundColor());
135        updateListViewVisibility();
136    }
137
138    private void updateListViewVisibility() {
139        final VerticalGridView listView = getVerticalGridView();
140        if (listView != null) {
141            getView().setVisibility(mHeadersGone ? View.GONE : View.VISIBLE);
142            if (!mHeadersGone) {
143                if (mHeadersEnabled) {
144                    listView.setChildrenVisibility(View.VISIBLE);
145                } else {
146                    listView.setChildrenVisibility(View.INVISIBLE);
147                }
148            }
149        }
150    }
151
152    void setHeadersEnabled(boolean enabled) {
153        mHeadersEnabled = enabled;
154        updateListViewVisibility();
155    }
156
157    void setHeadersGone(boolean gone) {
158        mHeadersGone = gone;
159        updateListViewVisibility();
160    }
161
162    static class NoOverlappingFrameLayout extends FrameLayout {
163
164        public NoOverlappingFrameLayout(Context context) {
165            super(context);
166        }
167
168        /**
169         * Avoid creating hardware layer for header dock.
170         */
171        @Override
172        public boolean hasOverlappingRendering() {
173            return false;
174        }
175    }
176
177    // Wrapper needed because of conflict between RecyclerView's use of alpha
178    // for ADD animations, and RowHeaderPresnter's use of alpha for selected level.
179    private final ItemBridgeAdapter.Wrapper mWrapper = new ItemBridgeAdapter.Wrapper() {
180        @Override
181        public void wrap(View wrapper, View wrapped) {
182            ((FrameLayout) wrapper).addView(wrapped);
183        }
184
185        @Override
186        public View createWrapper(View root) {
187            return new NoOverlappingFrameLayout(root.getContext());
188        }
189    };
190    @Override
191    protected void updateAdapter() {
192        super.updateAdapter();
193        ItemBridgeAdapter adapter = getBridgeAdapter();
194        if (adapter != null) {
195            adapter.setAdapterListener(mAdapterListener);
196            adapter.setWrapper(mWrapper);
197        }
198        if (adapter != null && getVerticalGridView() != null) {
199            FocusHighlightHelper.setupHeaderItemFocusHighlight(getVerticalGridView());
200        }
201    }
202
203    void setBackgroundColor(int color) {
204        mBackgroundColor = color;
205        mBackgroundColorSet = true;
206
207        if (getView() != null) {
208            getView().setBackgroundColor(mBackgroundColor);
209            updateFadingEdgeToBrandColor(mBackgroundColor);
210        }
211    }
212
213    private void updateFadingEdgeToBrandColor(int backgroundColor) {
214        View fadingView = getView().findViewById(R.id.fade_out_edge);
215        Drawable background = fadingView.getBackground();
216        if (background instanceof GradientDrawable) {
217            background.mutate();
218            ((GradientDrawable) background).setColors(
219                    new int[] {Color.TRANSPARENT, backgroundColor});
220        }
221    }
222
223    int getBackgroundColor() {
224        if (getActivity() == null) {
225            throw new IllegalStateException("Activity must be attached");
226        }
227
228        if (mBackgroundColorSet) {
229            return mBackgroundColor;
230        }
231
232        TypedValue outValue = new TypedValue();
233        getActivity().getTheme().resolveAttribute(R.attr.defaultBrandColor, outValue, true);
234        return getResources().getColor(outValue.resourceId);
235    }
236
237    @Override
238    void onTransitionStart() {
239        super.onTransitionStart();
240        if (!mHeadersEnabled) {
241            // When enabling headers fragment,  the RowHeaderView gets a focus but
242            // isShown() is still false because its parent is INVSIBILE, accessibility
243            // event is not sent.
244            // Workaround is: prevent focus to a child view during transition and put
245            // focus on it after transition is done.
246            final VerticalGridView listView = getVerticalGridView();
247            if (listView != null) {
248                listView.setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
249                if (listView.hasFocus()) {
250                    listView.requestFocus();
251                }
252            }
253        }
254    }
255
256    @Override
257    void onTransitionEnd() {
258        if (mHeadersEnabled) {
259            final VerticalGridView listView = getVerticalGridView();
260            if (listView != null) {
261                listView.setDescendantFocusability(ViewGroup.FOCUS_AFTER_DESCENDANTS);
262                if (listView.hasFocus()) {
263                    listView.requestFocus();
264                }
265            }
266        }
267        super.onTransitionEnd();
268    }
269}
270