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 android.content.Context;
17import android.graphics.Rect;
18import android.util.AttributeSet;
19import android.view.View;
20import android.widget.FrameLayout;
21
22/**
23 * A ViewGroup for managing focus behavior between overlapping views.
24 */
25public class BrowseFrameLayout extends FrameLayout {
26
27    /**
28     * Interface for selecting a focused view in a BrowseFrameLayout when the system focus finder
29     * couldn't find a view to focus.
30     */
31    public interface OnFocusSearchListener {
32        /**
33         * Returns the view where focus should be requested given the current focused view and
34         * the direction of focus search.
35         */
36        View onFocusSearch(View focused, int direction);
37    }
38
39    /**
40     * Interface for managing child focus in a BrowseFrameLayout.
41     */
42    public interface OnChildFocusListener {
43        /**
44         * See {@link android.view.ViewGroup#onRequestFocusInDescendants(
45         * int, android.graphics.Rect)}.
46         */
47        boolean onRequestFocusInDescendants(int direction,
48                Rect previouslyFocusedRect);
49        /**
50         * See {@link android.view.ViewGroup#requestChildFocus(
51         * android.view.View, android.view.View)}.
52         */
53        void onRequestChildFocus(View child, View focused);
54    }
55
56    public BrowseFrameLayout(Context context) {
57        this(context, null, 0);
58    }
59
60    public BrowseFrameLayout(Context context, AttributeSet attrs) {
61        this(context, attrs, 0);
62    }
63
64    public BrowseFrameLayout(Context context, AttributeSet attrs, int defStyle) {
65        super(context, attrs, defStyle);
66    }
67
68    private OnFocusSearchListener mListener;
69    private OnChildFocusListener mOnChildFocusListener;
70
71    /**
72     * Sets a {@link OnFocusSearchListener}.
73     */
74    public void setOnFocusSearchListener(OnFocusSearchListener listener) {
75        mListener = listener;
76    }
77
78    /**
79     * Returns the {@link OnFocusSearchListener}.
80     */
81    public OnFocusSearchListener getOnFocusSearchListener() {
82        return mListener;
83    }
84
85    /**
86     * Sets a {@link OnChildFocusListener}.
87     */
88    public void setOnChildFocusListener(OnChildFocusListener listener) {
89        mOnChildFocusListener = listener;
90    }
91
92    /**
93     * Returns the {@link OnChildFocusListener}.
94     */
95    public OnChildFocusListener getOnChildFocusListener() {
96        return mOnChildFocusListener;
97    }
98
99    @Override
100    protected boolean onRequestFocusInDescendants(int direction,
101            Rect previouslyFocusedRect) {
102        if (mOnChildFocusListener != null) {
103            return mOnChildFocusListener.onRequestFocusInDescendants(direction,
104                    previouslyFocusedRect);
105        }
106        return super.onRequestFocusInDescendants(direction, previouslyFocusedRect);
107    }
108
109    @Override
110    public View focusSearch(View focused, int direction) {
111        if (mListener != null) {
112            View view = mListener.onFocusSearch(focused, direction);
113            if (view != null) {
114                return view;
115            }
116        }
117        return super.focusSearch(focused, direction);
118    }
119
120    @Override
121    public void requestChildFocus(View child, View focused) {
122        super.requestChildFocus(child, focused);
123        if (mOnChildFocusListener != null) {
124            mOnChildFocusListener.onRequestChildFocus(child, focused);
125        }
126    }
127}
128