1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License
15 */
16
17package android.support.v17.leanback.widget;
18
19import android.support.v17.leanback.transition.LeanbackTransitionHelper;
20import android.support.v17.leanback.transition.TransitionHelper;
21import android.support.v4.view.ViewCompat;
22import android.view.View;
23import android.view.ViewGroup;
24
25/**
26 * Helper for managing {@link android.support.v17.leanback.widget.TitleView}, including
27 * transitions and focus movement.
28 * Assumes the TitleView is overlayed on the topmost portion of the scene root view.
29 */
30public class TitleHelper {
31
32    private ViewGroup mSceneRoot;
33    private View mTitleView;
34    private Object mTitleUpTransition;
35    private Object mTitleDownTransition;
36    private Object mSceneWithTitle;
37    private Object mSceneWithoutTitle;
38
39    // When moving focus off the TitleView, this focus search listener assumes that the view that
40    // should take focus comes before the TitleView in a focus search starting at the scene root.
41    private final BrowseFrameLayout.OnFocusSearchListener mOnFocusSearchListener =
42            new BrowseFrameLayout.OnFocusSearchListener() {
43        @Override
44        public View onFocusSearch(View focused, int direction) {
45            if (focused != mTitleView && direction == View.FOCUS_UP) {
46                return mTitleView;
47            }
48            final boolean isRtl = ViewCompat.getLayoutDirection(focused) ==
49                    View.LAYOUT_DIRECTION_RTL;
50            final int forward = isRtl ? View.FOCUS_LEFT : View.FOCUS_RIGHT;
51            if (mTitleView.hasFocus() && direction == View.FOCUS_DOWN || direction == forward) {
52                return mSceneRoot;
53            }
54            return null;
55        }
56    };
57
58    public TitleHelper(ViewGroup sceneRoot, View titleView) {
59        if (sceneRoot == null || titleView == null) {
60            throw new IllegalArgumentException("Views may not be null");
61        }
62        mSceneRoot = sceneRoot;
63        mTitleView = titleView;
64        createTransitions();
65    }
66
67    private void createTransitions() {
68        mTitleUpTransition = LeanbackTransitionHelper.loadTitleOutTransition(
69                mSceneRoot.getContext());
70        mTitleDownTransition = LeanbackTransitionHelper.loadTitleInTransition(
71                mSceneRoot.getContext());
72        mSceneWithTitle = TransitionHelper.createScene(mSceneRoot, new Runnable() {
73            @Override
74            public void run() {
75                mTitleView.setVisibility(View.VISIBLE);
76            }
77        });
78        mSceneWithoutTitle = TransitionHelper.createScene(mSceneRoot, new Runnable() {
79            @Override
80            public void run() {
81                mTitleView.setVisibility(View.INVISIBLE);
82            }
83        });
84    }
85
86    /**
87     * Shows the title.
88     */
89    public void showTitle(boolean show) {
90        if (show) {
91            TransitionHelper.runTransition(mSceneWithTitle, mTitleDownTransition);
92        } else {
93            TransitionHelper.runTransition(mSceneWithoutTitle, mTitleUpTransition);
94        }
95    }
96
97    /**
98     * Returns the scene root ViewGroup.
99     */
100    public ViewGroup getSceneRoot() {
101        return mSceneRoot;
102    }
103
104    /**
105     * Returns the {@link TitleView}
106     */
107    public View getTitleView() {
108        return mTitleView;
109    }
110
111    /**
112     * Returns a
113     * {@link android.support.v17.leanback.widget.BrowseFrameLayout.OnFocusSearchListener} which
114     * may be used to manage focus switching between the title view and scene root.
115     */
116    public BrowseFrameLayout.OnFocusSearchListener getOnFocusSearchListener() {
117        return mOnFocusSearchListener;
118    }
119}
120