1 /*
2  * Copyright (C) 2012 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 
17 package com.android.launcher2;
18 
19 import android.view.View;
20 import android.view.ViewGroup;
21 import android.view.ViewGroup.OnHierarchyChangeListener;
22 
23 import java.util.HashMap;
24 
25 public class HideFromAccessibilityHelper implements OnHierarchyChangeListener {
26     private HashMap<View, Integer> mPreviousValues;
27     boolean mHide;
28     boolean mOnlyAllApps;
29 
HideFromAccessibilityHelper()30     public HideFromAccessibilityHelper() {
31         mPreviousValues = new HashMap<View, Integer>();
32         mHide = false;
33     }
34 
setImportantForAccessibilityToNo(View v, boolean onlyAllApps)35     public void setImportantForAccessibilityToNo(View v, boolean onlyAllApps) {
36         mOnlyAllApps = onlyAllApps;
37         setImportantForAccessibilityToNoHelper(v);
38         mHide = true;
39     }
40 
setImportantForAccessibilityToNoHelper(View v)41     private void setImportantForAccessibilityToNoHelper(View v) {
42         mPreviousValues.put(v, v.getImportantForAccessibility());
43         v.setImportantForAccessibility(View.IMPORTANT_FOR_ACCESSIBILITY_NO);
44 
45         // Call method on children recursively
46         if (v instanceof ViewGroup) {
47             ViewGroup vg = (ViewGroup) v;
48             vg.setOnHierarchyChangeListener(this);
49             for (int i = 0; i < vg.getChildCount(); i++) {
50                 View child = vg.getChildAt(i);
51 
52                 if (includeView(child)) {
53                     setImportantForAccessibilityToNoHelper(child);
54                 }
55             }
56         }
57     }
58 
restoreImportantForAccessibility(View v)59     public void restoreImportantForAccessibility(View v) {
60         if (mHide) {
61             restoreImportantForAccessibilityHelper(v);
62         }
63         mHide = false;
64     }
65 
restoreImportantForAccessibilityHelper(View v)66     private void restoreImportantForAccessibilityHelper(View v) {
67         v.setImportantForAccessibility(mPreviousValues.get(v));
68         mPreviousValues.remove(v);
69 
70         // Call method on children recursively
71         if (v instanceof ViewGroup) {
72             ViewGroup vg = (ViewGroup) v;
73 
74             // We assume if a class implements OnHierarchyChangeListener, it listens
75             // to changes to any of its children (happens to be the case in Launcher)
76             if (vg instanceof OnHierarchyChangeListener) {
77                 vg.setOnHierarchyChangeListener((OnHierarchyChangeListener) vg);
78             } else {
79                 vg.setOnHierarchyChangeListener(null);
80             }
81             for (int i = 0; i < vg.getChildCount(); i++) {
82                 View child = vg.getChildAt(i);
83                 if (includeView(child)) {
84                     restoreImportantForAccessibilityHelper(child);
85                 }
86             }
87         }
88     }
89 
onChildViewAdded(View parent, View child)90     public void onChildViewAdded(View parent, View child) {
91         if (mHide && includeView(child)) {
92             setImportantForAccessibilityToNoHelper(child);
93         }
94     }
95 
onChildViewRemoved(View parent, View child)96     public void onChildViewRemoved(View parent, View child) {
97         if (mHide && includeView(child)) {
98             restoreImportantForAccessibilityHelper(child);
99         }
100     }
101 
includeView(View v)102     private boolean includeView(View v) {
103         return !hasAncestorOfType(v, Cling.class) &&
104                 (!mOnlyAllApps || hasAncestorOfType(v, AppsCustomizeTabHost.class));
105     }
106 
hasAncestorOfType(View v, Class c)107     private boolean hasAncestorOfType(View v, Class c) {
108         return v != null &&
109                 (v.getClass().equals(c) ||
110                  (v.getParent() instanceof ViewGroup &&
111                   hasAncestorOfType((ViewGroup) v.getParent(), c)));
112     }
113 }