1/*
2 * Copyright (C) 2016 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 */
16package com.android.documentsui;
17
18import android.content.Context;
19import android.util.AttributeSet;
20import android.view.KeyEvent;
21import android.widget.ListView;
22
23/**
24 * The list in the navigation drawer. This class exists for the purpose of overriding the key
25 * handler on ListView. Ignoring keystrokes (e.g. the tab key) cannot be properly done using
26 * View.OnKeyListener.
27 */
28public class RootsList extends ListView {
29
30    // Multiple constructors are needed to handle all the different ways this View could be
31    // constructed by the framework. Don't remove them!
32    public RootsList(Context context) {
33        super(context);
34    }
35
36    public RootsList(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
37        super(context, attrs, defStyleAttr, defStyleRes);
38    }
39
40    public RootsList(Context context, AttributeSet attrs, int defStyleAttr) {
41        super(context, attrs, defStyleAttr);
42    }
43
44    public RootsList(Context context, AttributeSet attrs) {
45        super(context, attrs);
46    }
47
48    @Override
49    public boolean onKeyDown(int keyCode, KeyEvent event) {
50        switch (keyCode) {
51            // Ignore tab key events - this causes them to bubble up to the global key handler where
52            // they are appropriately handled. See BaseActivity.onKeyDown.
53            case KeyEvent.KEYCODE_TAB:
54                return false;
55            // Prevent left/right arrow keystrokes from shifting focus away from the roots list.
56            case KeyEvent.KEYCODE_DPAD_LEFT:
57            case KeyEvent.KEYCODE_DPAD_RIGHT:
58                return true;
59            default:
60                return super.onKeyDown(keyCode, event);
61        }
62    }
63}
64