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