1/*
2 * Copyright (C) 2011 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.keyguard;
18
19import android.content.Context;
20import android.os.Handler;
21import android.os.Looper;
22import android.os.SystemClock;
23import android.text.TextUtils;
24import android.util.AttributeSet;
25import android.view.View;
26import android.widget.TextView;
27
28import java.lang.ref.WeakReference;
29
30/***
31 * Manages a number of views inside of the given layout. See below for a list of widgets.
32 */
33class KeyguardMessageArea extends TextView implements SecurityMessageDisplay {
34    /** Handler token posted with accessibility announcement runnables. */
35    private static final Object ANNOUNCE_TOKEN = new Object();
36
37    /**
38     * Delay before speaking an accessibility announcement. Used to prevent
39     * lift-to-type from interrupting itself.
40     */
41    private static final long ANNOUNCEMENT_DELAY = 250;
42    private static final int DEFAULT_COLOR = -1;
43
44    private final Handler mHandler;
45    private final int mDefaultColor;
46
47    private CharSequence mMessage;
48    private int mNextMessageColor = DEFAULT_COLOR;
49
50    private KeyguardUpdateMonitorCallback mInfoCallback = new KeyguardUpdateMonitorCallback() {
51        public void onFinishedGoingToSleep(int why) {
52            setSelected(false);
53        };
54        public void onStartedWakingUp() {
55            setSelected(true);
56        };
57    };
58
59    public KeyguardMessageArea(Context context) {
60        this(context, null);
61    }
62
63    public KeyguardMessageArea(Context context, AttributeSet attrs) {
64        this(context, attrs, KeyguardUpdateMonitor.getInstance(context));
65    }
66
67    public KeyguardMessageArea(Context context, AttributeSet attrs, KeyguardUpdateMonitor monitor) {
68        super(context, attrs);
69        setLayerType(LAYER_TYPE_HARDWARE, null); // work around nested unclipped SaveLayer bug
70
71        monitor.registerCallback(mInfoCallback);
72        mHandler = new Handler(Looper.myLooper());
73
74        mDefaultColor = getCurrentTextColor();
75        update();
76    }
77
78    @Override
79    public void setNextMessageColor(int color) {
80        mNextMessageColor = color;
81    }
82
83    @Override
84    public void setMessage(CharSequence msg) {
85        if (!TextUtils.isEmpty(msg)) {
86            securityMessageChanged(msg);
87        } else {
88            clearMessage();
89        }
90    }
91
92    @Override
93    public void setMessage(int resId) {
94        CharSequence message = null;
95        if (resId != 0) {
96            message = getContext().getResources().getText(resId);
97        }
98        setMessage(message);
99    }
100
101    @Override
102    public void formatMessage(int resId, Object... formatArgs) {
103        CharSequence message = null;
104        if (resId != 0) {
105            message = getContext().getString(resId, formatArgs);
106        }
107        setMessage(message);
108    }
109
110    public static SecurityMessageDisplay findSecurityMessageDisplay(View v) {
111        KeyguardMessageArea messageArea = (KeyguardMessageArea) v.findViewById(
112                R.id.keyguard_message_area);
113        if (messageArea == null) {
114            throw new RuntimeException("Can't find keyguard_message_area in " + v.getClass());
115        }
116        return messageArea;
117    }
118
119    @Override
120    protected void onFinishInflate() {
121        boolean shouldMarquee = KeyguardUpdateMonitor.getInstance(mContext).isDeviceInteractive();
122        setSelected(shouldMarquee); // This is required to ensure marquee works
123    }
124
125    private void securityMessageChanged(CharSequence message) {
126        mMessage = message;
127        update();
128        mHandler.removeCallbacksAndMessages(ANNOUNCE_TOKEN);
129        mHandler.postAtTime(new AnnounceRunnable(this, getText()), ANNOUNCE_TOKEN,
130                (SystemClock.uptimeMillis() + ANNOUNCEMENT_DELAY));
131    }
132
133    private void clearMessage() {
134        mMessage = null;
135        update();
136    }
137
138    private void update() {
139        CharSequence status = mMessage;
140        setVisibility(TextUtils.isEmpty(status) ? INVISIBLE : VISIBLE);
141        setText(status);
142        int color = mDefaultColor;
143        if (mNextMessageColor != DEFAULT_COLOR) {
144            color = mNextMessageColor;
145            mNextMessageColor = DEFAULT_COLOR;
146        }
147        setTextColor(color);
148    }
149
150
151    /**
152     * Runnable used to delay accessibility announcements.
153     */
154    private static class AnnounceRunnable implements Runnable {
155        private final WeakReference<View> mHost;
156        private final CharSequence mTextToAnnounce;
157
158        AnnounceRunnable(View host, CharSequence textToAnnounce) {
159            mHost = new WeakReference<View>(host);
160            mTextToAnnounce = textToAnnounce;
161        }
162
163        @Override
164        public void run() {
165            final View host = mHost.get();
166            if (host != null) {
167                host.announceForAccessibility(mTextToAnnounce);
168            }
169        }
170    }
171}
172