1/*
2 * Copyright (C) 2014 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
17package com.android.systemui.statusbar.policy;
18
19import android.content.Context;
20import android.view.accessibility.AccessibilityManager;
21
22import java.io.FileDescriptor;
23import java.io.PrintWriter;
24import java.util.ArrayList;
25
26public class AccessibilityController implements
27        AccessibilityManager.AccessibilityStateChangeListener,
28        AccessibilityManager.TouchExplorationStateChangeListener {
29
30    private final ArrayList<AccessibilityStateChangedCallback> mChangeCallbacks = new ArrayList<>();
31
32    private boolean mAccessibilityEnabled;
33    private boolean mTouchExplorationEnabled;
34
35    public AccessibilityController(Context context) {
36        AccessibilityManager am =
37                (AccessibilityManager) context.getSystemService(Context.ACCESSIBILITY_SERVICE);
38        am.addTouchExplorationStateChangeListener(this);
39        am.addAccessibilityStateChangeListener(this);
40        mAccessibilityEnabled = am.isEnabled();
41        mTouchExplorationEnabled = am.isTouchExplorationEnabled();
42    }
43
44    public boolean isAccessibilityEnabled() {
45        return mAccessibilityEnabled;
46    }
47
48    public boolean isTouchExplorationEnabled() {
49        return mTouchExplorationEnabled;
50    }
51
52    public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
53        pw.println("AccessibilityController state:");
54        pw.print("  mAccessibilityEnabled="); pw.println(mAccessibilityEnabled);
55        pw.print("  mTouchExplorationEnabled="); pw.println(mTouchExplorationEnabled);
56    }
57
58    public void addStateChangedCallback(AccessibilityStateChangedCallback cb) {
59        mChangeCallbacks.add(cb);
60        cb.onStateChanged(mAccessibilityEnabled, mTouchExplorationEnabled);
61    }
62
63    public void removeStateChangedCallback(AccessibilityStateChangedCallback cb) {
64        mChangeCallbacks.remove(cb);
65    }
66
67    private void fireChanged() {
68        final int N = mChangeCallbacks.size();
69        for (int i = 0; i < N; i++) {
70            mChangeCallbacks.get(i).onStateChanged(mAccessibilityEnabled, mTouchExplorationEnabled);
71        }
72    }
73
74    @Override
75    public void onAccessibilityStateChanged(boolean enabled) {
76        mAccessibilityEnabled = enabled;
77        fireChanged();
78    }
79
80    @Override
81    public void onTouchExplorationStateChanged(boolean enabled) {
82        mTouchExplorationEnabled = enabled;
83        fireChanged();
84    }
85
86    public interface AccessibilityStateChangedCallback {
87        void onStateChanged(boolean accessibilityEnabled, boolean touchExplorationEnabled);
88    }
89}
90