BrowseFrameLayout.java revision e7246ef136ed686d8caf339d4d1fd8e37b499c6a 
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 * Top level implementation viewgroup for managing focus behavior between overlapping views.
24 */
25public class BrowseFrameLayout extends FrameLayout {
26
27    /**
28     * Interface for selecting a focused view when the system focus finder couldn't find a view
29     * 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        public View onFocusSearch(View focused, int direction);
37    }
38
39    /**
40     * Interface for managing child focus.
41     */
42    public interface OnChildFocusListener {
43        public boolean onRequestFocusInDescendants(int direction,
44                Rect previouslyFocusedRect);
45        public void onRequestChildFocus(View child, View focused);
46    }
47
48    public BrowseFrameLayout(Context context) {
49        this(context, null, 0);
50    }
51
52    public BrowseFrameLayout(Context context, AttributeSet attrs) {
53        this(context, attrs, 0);
54    }
55
56    public BrowseFrameLayout(Context context, AttributeSet attrs, int defStyle) {
57        super(context, attrs, defStyle);
58    }
59
60    private OnFocusSearchListener mListener;
61    private OnChildFocusListener mOnChildFocusListener;
62
63    /**
64     * Sets an {@link OnFocusSearchListener}.
65     */
66    public void setOnFocusSearchListener(OnFocusSearchListener listener) {
67        mListener = listener;
68    }
69
70    /**
71     * Returns the {@link OnFocusSearchListener}.
72     */
73    public OnFocusSearchListener getOnFocusSearchListener() {
74        return mListener;
75    }
76
77    /**
78     * Sets an {@link OnChildFocusListener}.
79     */
80    public void setOnChildFocusListener(OnChildFocusListener listener) {
81        mOnChildFocusListener = listener;
82    }
83
84    /**
85     * Returns the {@link OnChildFocusListener}.
86     */
87    public OnChildFocusListener getOnChildFocusListener() {
88        return mOnChildFocusListener;
89    }
90
91    @Override
92    protected boolean onRequestFocusInDescendants(int direction,
93            Rect previouslyFocusedRect) {
94        if (mOnChildFocusListener != null) {
95            return mOnChildFocusListener.onRequestFocusInDescendants(direction,
96                    previouslyFocusedRect);
97        }
98        return super.onRequestFocusInDescendants(direction, previouslyFocusedRect);
99    }
100
101    @Override
102    public View focusSearch(View focused, int direction) {
103        if (mListener != null) {
104            View view = mListener.onFocusSearch(focused, direction);
105            if (view != null) {
106                return view;
107            }
108        }
109        return super.focusSearch(focused, direction);
110    }
111
112    @Override
113    public void requestChildFocus(View child, View focused) {
114        super.requestChildFocus(child, focused);
115        if (mOnChildFocusListener != null) {
116            mOnChildFocusListener.onRequestChildFocus(child, focused);
117        }
118    }
119}
120