1 /*
2  * Copyright (C) 2010 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 android.widget;
18 
19 import static android.text.format.DateUtils.DAY_IN_MILLIS;
20 import static android.text.format.DateUtils.HOUR_IN_MILLIS;
21 import static android.text.format.DateUtils.MINUTE_IN_MILLIS;
22 import static android.text.format.DateUtils.YEAR_IN_MILLIS;
23 
24 import android.app.ActivityThread;
25 import android.compat.annotation.UnsupportedAppUsage;
26 import android.content.BroadcastReceiver;
27 import android.content.Context;
28 import android.content.Intent;
29 import android.content.IntentFilter;
30 import android.content.res.Configuration;
31 import android.content.res.TypedArray;
32 import android.database.ContentObserver;
33 import android.os.Handler;
34 import android.util.AttributeSet;
35 import android.view.accessibility.AccessibilityNodeInfo;
36 import android.view.inspector.InspectableProperty;
37 import android.widget.RemoteViews.RemoteView;
38 
39 import com.android.internal.R;
40 
41 import java.text.DateFormat;
42 import java.time.Instant;
43 import java.time.LocalDate;
44 import java.time.LocalDateTime;
45 import java.time.LocalTime;
46 import java.time.ZoneId;
47 import java.time.temporal.JulianFields;
48 import java.util.ArrayList;
49 import java.util.Date;
50 
51 //
52 // TODO
53 // - listen for the next threshold time to update the view.
54 // - listen for date format pref changed
55 // - put the AM/PM in a smaller font
56 //
57 
58 /**
59  * Displays a given time in a convenient human-readable foramt.
60  *
61  * @hide
62  */
63 @RemoteView
64 public class DateTimeView extends TextView {
65     private static final int SHOW_TIME = 0;
66     private static final int SHOW_MONTH_DAY_YEAR = 1;
67 
68     private long mTimeMillis;
69     // The LocalDateTime equivalent of mTimeMillis but truncated to minute, i.e. no seconds / nanos.
70     private LocalDateTime mLocalTime;
71 
72     int mLastDisplay = -1;
73     DateFormat mLastFormat;
74 
75     private long mUpdateTimeMillis;
76     private static final ThreadLocal<ReceiverInfo> sReceiverInfo = new ThreadLocal<ReceiverInfo>();
77     private String mNowText;
78     private boolean mShowRelativeTime;
79 
DateTimeView(Context context)80     public DateTimeView(Context context) {
81         this(context, null);
82     }
83 
84     @UnsupportedAppUsage
DateTimeView(Context context, AttributeSet attrs)85     public DateTimeView(Context context, AttributeSet attrs) {
86         super(context, attrs);
87         final TypedArray a = context.obtainStyledAttributes(attrs,
88                 com.android.internal.R.styleable.DateTimeView, 0,
89                 0);
90 
91         final int N = a.getIndexCount();
92         for (int i = 0; i < N; i++) {
93             int attr = a.getIndex(i);
94             switch (attr) {
95                 case R.styleable.DateTimeView_showRelative:
96                     boolean relative = a.getBoolean(i, false);
97                     setShowRelativeTime(relative);
98                     break;
99             }
100         }
101         a.recycle();
102     }
103 
104     @Override
onAttachedToWindow()105     protected void onAttachedToWindow() {
106         super.onAttachedToWindow();
107         ReceiverInfo ri = sReceiverInfo.get();
108         if (ri == null) {
109             ri = new ReceiverInfo();
110             sReceiverInfo.set(ri);
111         }
112         ri.addView(this);
113         // The view may not be added to the view hierarchy immediately right after setTime()
114         // is called which means it won't get any update from intents before being added.
115         // In such case, the view might show the incorrect relative time after being added to the
116         // view hierarchy until the next update intent comes.
117         // So we update the time here if mShowRelativeTime is enabled to prevent this case.
118         if (mShowRelativeTime) {
119             update();
120         }
121     }
122 
123     @Override
onDetachedFromWindow()124     protected void onDetachedFromWindow() {
125         super.onDetachedFromWindow();
126         final ReceiverInfo ri = sReceiverInfo.get();
127         if (ri != null) {
128             ri.removeView(this);
129         }
130     }
131 
132     @android.view.RemotableViewMethod
133     @UnsupportedAppUsage
setTime(long timeMillis)134     public void setTime(long timeMillis) {
135         mTimeMillis = timeMillis;
136         LocalDateTime dateTime = toLocalDateTime(timeMillis, ZoneId.systemDefault());
137         mLocalTime = dateTime.withSecond(0);
138         update();
139     }
140 
141     @android.view.RemotableViewMethod
setShowRelativeTime(boolean showRelativeTime)142     public void setShowRelativeTime(boolean showRelativeTime) {
143         mShowRelativeTime = showRelativeTime;
144         updateNowText();
145         update();
146     }
147 
148     /**
149      * Returns whether this view shows relative time
150      *
151      * @return True if it shows relative time, false otherwise
152      */
153     @InspectableProperty(name = "showReleative", hasAttributeId = false)
isShowRelativeTime()154     public boolean isShowRelativeTime() {
155         return mShowRelativeTime;
156     }
157 
158     @Override
159     @android.view.RemotableViewMethod
setVisibility(@isibility int visibility)160     public void setVisibility(@Visibility int visibility) {
161         boolean gotVisible = visibility != GONE && getVisibility() == GONE;
162         super.setVisibility(visibility);
163         if (gotVisible) {
164             update();
165         }
166     }
167 
168     @UnsupportedAppUsage
update()169     void update() {
170         if (mLocalTime == null || getVisibility() == GONE) {
171             return;
172         }
173         if (mShowRelativeTime) {
174             updateRelativeTime();
175             return;
176         }
177 
178         int display;
179         ZoneId zoneId = ZoneId.systemDefault();
180 
181         // localTime is the local time for mTimeMillis but at zero seconds past the minute.
182         LocalDateTime localTime = mLocalTime;
183         LocalDateTime localStartOfDay =
184                 LocalDateTime.of(localTime.toLocalDate(), LocalTime.MIDNIGHT);
185         LocalDateTime localTomorrowStartOfDay = localStartOfDay.plusDays(1);
186         // now is current local time but at zero seconds past the minute.
187         LocalDateTime localNow = LocalDateTime.now(zoneId).withSecond(0);
188 
189         long twelveHoursBefore = toEpochMillis(localTime.minusHours(12), zoneId);
190         long twelveHoursAfter = toEpochMillis(localTime.plusHours(12), zoneId);
191         long midnightBefore = toEpochMillis(localStartOfDay, zoneId);
192         long midnightAfter = toEpochMillis(localTomorrowStartOfDay, zoneId);
193         long time = toEpochMillis(localTime, zoneId);
194         long now = toEpochMillis(localNow, zoneId);
195 
196         // Choose the display mode
197         choose_display: {
198             if ((now >= midnightBefore && now < midnightAfter)
199                     || (now >= twelveHoursBefore && now < twelveHoursAfter)) {
200                 display = SHOW_TIME;
201                 break choose_display;
202             }
203             // Else, show month day and year.
204             display = SHOW_MONTH_DAY_YEAR;
205             break choose_display;
206         }
207 
208         // Choose the format
209         DateFormat format;
210         if (display == mLastDisplay && mLastFormat != null) {
211             // use cached format
212             format = mLastFormat;
213         } else {
214             switch (display) {
215                 case SHOW_TIME:
216                     format = getTimeFormat();
217                     break;
218                 case SHOW_MONTH_DAY_YEAR:
219                     format = DateFormat.getDateInstance(DateFormat.SHORT);
220                     break;
221                 default:
222                     throw new RuntimeException("unknown display value: " + display);
223             }
224             mLastFormat = format;
225         }
226 
227         // Set the text
228         String text = format.format(new Date(time));
229         setText(text);
230 
231         // Schedule the next update
232         if (display == SHOW_TIME) {
233             // Currently showing the time, update at the later of twelve hours after or midnight.
234             mUpdateTimeMillis = twelveHoursAfter > midnightAfter ? twelveHoursAfter : midnightAfter;
235         } else {
236             // Currently showing the date
237             if (mTimeMillis < now) {
238                 // If the time is in the past, don't schedule an update
239                 mUpdateTimeMillis = 0;
240             } else {
241                 // If hte time is in the future, schedule one at the earlier of twelve hours
242                 // before or midnight before.
243                 mUpdateTimeMillis = twelveHoursBefore < midnightBefore
244                         ? twelveHoursBefore : midnightBefore;
245             }
246         }
247     }
248 
249     private void updateRelativeTime() {
250         long now = System.currentTimeMillis();
251         long duration = Math.abs(now - mTimeMillis);
252         int count;
253         long millisIncrease;
254         boolean past = (now >= mTimeMillis);
255         String result;
256         if (duration < MINUTE_IN_MILLIS) {
257             setText(mNowText);
258             mUpdateTimeMillis = mTimeMillis + MINUTE_IN_MILLIS + 1;
259             return;
260         } else if (duration < HOUR_IN_MILLIS) {
261             count = (int)(duration / MINUTE_IN_MILLIS);
262             result = String.format(getContext().getResources().getQuantityString(past
263                             ? com.android.internal.R.plurals.duration_minutes_shortest
264                             : com.android.internal.R.plurals.duration_minutes_shortest_future,
265                             count),
266                     count);
267             millisIncrease = MINUTE_IN_MILLIS;
268         } else if (duration < DAY_IN_MILLIS) {
269             count = (int)(duration / HOUR_IN_MILLIS);
270             result = String.format(getContext().getResources().getQuantityString(past
271                             ? com.android.internal.R.plurals.duration_hours_shortest
272                             : com.android.internal.R.plurals.duration_hours_shortest_future,
273                             count),
274                     count);
275             millisIncrease = HOUR_IN_MILLIS;
276         } else if (duration < YEAR_IN_MILLIS) {
277             // In weird cases it can become 0 because of daylight savings
278             LocalDateTime localDateTime = mLocalTime;
279             ZoneId zoneId = ZoneId.systemDefault();
280             LocalDateTime localNow = toLocalDateTime(now, zoneId);
281 
282             count = Math.max(Math.abs(dayDistance(localDateTime, localNow)), 1);
283             result = String.format(getContext().getResources().getQuantityString(past
284                             ? com.android.internal.R.plurals.duration_days_shortest
285                             : com.android.internal.R.plurals.duration_days_shortest_future,
286                             count),
287                     count);
288             if (past || count != 1) {
289                 mUpdateTimeMillis = computeNextMidnight(localNow, zoneId);
290                 millisIncrease = -1;
291             } else {
292                 millisIncrease = DAY_IN_MILLIS;
293             }
294 
295         } else {
296             count = (int)(duration / YEAR_IN_MILLIS);
297             result = String.format(getContext().getResources().getQuantityString(past
298                             ? com.android.internal.R.plurals.duration_years_shortest
299                             : com.android.internal.R.plurals.duration_years_shortest_future,
300                             count),
301                     count);
302             millisIncrease = YEAR_IN_MILLIS;
303         }
304         if (millisIncrease != -1) {
305             if (past) {
306                 mUpdateTimeMillis = mTimeMillis + millisIncrease * (count + 1) + 1;
307             } else {
308                 mUpdateTimeMillis = mTimeMillis - millisIncrease * count + 1;
309             }
310         }
311         setText(result);
312     }
313 
314     /**
315      * Returns the epoch millis for the next midnight in the specified timezone.
316      */
computeNextMidnight(LocalDateTime time, ZoneId zoneId)317     private static long computeNextMidnight(LocalDateTime time, ZoneId zoneId) {
318         // This ignores the chance of overflow: it should never happen.
319         LocalDate tomorrow = time.toLocalDate().plusDays(1);
320         LocalDateTime nextMidnight = LocalDateTime.of(tomorrow, LocalTime.MIDNIGHT);
321         return toEpochMillis(nextMidnight, zoneId);
322     }
323 
324     @Override
onConfigurationChanged(Configuration newConfig)325     protected void onConfigurationChanged(Configuration newConfig) {
326         super.onConfigurationChanged(newConfig);
327         updateNowText();
328         update();
329     }
330 
updateNowText()331     private void updateNowText() {
332         if (!mShowRelativeTime) {
333             return;
334         }
335         mNowText = getContext().getResources().getString(
336                 com.android.internal.R.string.now_string_shortest);
337     }
338 
339     // Return the number of days between the two dates.
dayDistance(LocalDateTime start, LocalDateTime end)340     private static int dayDistance(LocalDateTime start, LocalDateTime end) {
341         return (int) (end.getLong(JulianFields.JULIAN_DAY)
342                 - start.getLong(JulianFields.JULIAN_DAY));
343     }
344 
getTimeFormat()345     private DateFormat getTimeFormat() {
346         return android.text.format.DateFormat.getTimeFormat(getContext());
347     }
348 
clearFormatAndUpdate()349     void clearFormatAndUpdate() {
350         mLastFormat = null;
351         update();
352     }
353 
354     @Override
onInitializeAccessibilityNodeInfoInternal(AccessibilityNodeInfo info)355     public void onInitializeAccessibilityNodeInfoInternal(AccessibilityNodeInfo info) {
356         super.onInitializeAccessibilityNodeInfoInternal(info);
357         if (mShowRelativeTime) {
358             // The short version of the time might not be completely understandable and for
359             // accessibility we rather have a longer version.
360             long now = System.currentTimeMillis();
361             long duration = Math.abs(now - mTimeMillis);
362             int count;
363             boolean past = (now >= mTimeMillis);
364             String result;
365             if (duration < MINUTE_IN_MILLIS) {
366                 result = mNowText;
367             } else if (duration < HOUR_IN_MILLIS) {
368                 count = (int)(duration / MINUTE_IN_MILLIS);
369                 result = String.format(getContext().getResources().getQuantityString(past
370                                 ? com.android.internal.
371                                         R.plurals.duration_minutes_relative
372                                 : com.android.internal.
373                                         R.plurals.duration_minutes_relative_future,
374                         count),
375                         count);
376             } else if (duration < DAY_IN_MILLIS) {
377                 count = (int)(duration / HOUR_IN_MILLIS);
378                 result = String.format(getContext().getResources().getQuantityString(past
379                                 ? com.android.internal.
380                                         R.plurals.duration_hours_relative
381                                 : com.android.internal.
382                                         R.plurals.duration_hours_relative_future,
383                         count),
384                         count);
385             } else if (duration < YEAR_IN_MILLIS) {
386                 // In weird cases it can become 0 because of daylight savings
387                 LocalDateTime localDateTime = mLocalTime;
388                 ZoneId zoneId = ZoneId.systemDefault();
389                 LocalDateTime localNow = toLocalDateTime(now, zoneId);
390 
391                 count = Math.max(Math.abs(dayDistance(localDateTime, localNow)), 1);
392                 result = String.format(getContext().getResources().getQuantityString(past
393                                 ? com.android.internal.
394                                         R.plurals.duration_days_relative
395                                 : com.android.internal.
396                                         R.plurals.duration_days_relative_future,
397                         count),
398                         count);
399 
400             } else {
401                 count = (int)(duration / YEAR_IN_MILLIS);
402                 result = String.format(getContext().getResources().getQuantityString(past
403                                 ? com.android.internal.
404                                         R.plurals.duration_years_relative
405                                 : com.android.internal.
406                                         R.plurals.duration_years_relative_future,
407                         count),
408                         count);
409             }
410             info.setText(result);
411         }
412     }
413 
414     /**
415      * @hide
416      */
setReceiverHandler(Handler handler)417     public static void setReceiverHandler(Handler handler) {
418         ReceiverInfo ri = sReceiverInfo.get();
419         if (ri == null) {
420             ri = new ReceiverInfo();
421             sReceiverInfo.set(ri);
422         }
423         ri.setHandler(handler);
424     }
425 
426     private static class ReceiverInfo {
427         private final ArrayList<DateTimeView> mAttachedViews = new ArrayList<DateTimeView>();
428         private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
429             @Override
430             public void onReceive(Context context, Intent intent) {
431                 String action = intent.getAction();
432                 if (Intent.ACTION_TIME_TICK.equals(action)) {
433                     if (System.currentTimeMillis() < getSoonestUpdateTime()) {
434                         // The update() function takes a few milliseconds to run because of
435                         // all of the time conversions it needs to do, so we can't do that
436                         // every minute.
437                         return;
438                     }
439                 }
440                 // ACTION_TIME_CHANGED can also signal a change of 12/24 hr. format.
441                 updateAll();
442             }
443         };
444 
445         private final ContentObserver mObserver = new ContentObserver(new Handler()) {
446             @Override
447             public void onChange(boolean selfChange) {
448                 updateAll();
449             }
450         };
451 
452         private Handler mHandler = new Handler();
453 
addView(DateTimeView v)454         public void addView(DateTimeView v) {
455             synchronized (mAttachedViews) {
456                 final boolean register = mAttachedViews.isEmpty();
457                 mAttachedViews.add(v);
458                 if (register) {
459                     register(getApplicationContextIfAvailable(v.getContext()));
460                 }
461             }
462         }
463 
removeView(DateTimeView v)464         public void removeView(DateTimeView v) {
465             synchronized (mAttachedViews) {
466                 final boolean removed = mAttachedViews.remove(v);
467                 // Only unregister once when we remove the last view in the list otherwise we risk
468                 // trying to unregister a receiver that is no longer registered.
469                 if (removed && mAttachedViews.isEmpty()) {
470                     unregister(getApplicationContextIfAvailable(v.getContext()));
471                 }
472             }
473         }
474 
updateAll()475         void updateAll() {
476             synchronized (mAttachedViews) {
477                 final int count = mAttachedViews.size();
478                 for (int i = 0; i < count; i++) {
479                     DateTimeView view = mAttachedViews.get(i);
480                     view.post(() -> view.clearFormatAndUpdate());
481                 }
482             }
483         }
484 
getSoonestUpdateTime()485         long getSoonestUpdateTime() {
486             long result = Long.MAX_VALUE;
487             synchronized (mAttachedViews) {
488                 final int count = mAttachedViews.size();
489                 for (int i = 0; i < count; i++) {
490                     final long time = mAttachedViews.get(i).mUpdateTimeMillis;
491                     if (time < result) {
492                         result = time;
493                     }
494                 }
495             }
496             return result;
497         }
498 
getApplicationContextIfAvailable(Context context)499         static final Context getApplicationContextIfAvailable(Context context) {
500             final Context ac = context.getApplicationContext();
501             return ac != null ? ac : ActivityThread.currentApplication().getApplicationContext();
502         }
503 
register(Context context)504         void register(Context context) {
505             final IntentFilter filter = new IntentFilter();
506             filter.addAction(Intent.ACTION_TIME_TICK);
507             filter.addAction(Intent.ACTION_TIME_CHANGED);
508             filter.addAction(Intent.ACTION_CONFIGURATION_CHANGED);
509             filter.addAction(Intent.ACTION_TIMEZONE_CHANGED);
510             context.registerReceiver(mReceiver, filter, null, mHandler);
511         }
512 
unregister(Context context)513         void unregister(Context context) {
514             context.unregisterReceiver(mReceiver);
515         }
516 
setHandler(Handler handler)517         public void setHandler(Handler handler) {
518             mHandler = handler;
519             synchronized (mAttachedViews) {
520                 if (!mAttachedViews.isEmpty()) {
521                     unregister(mAttachedViews.get(0).getContext());
522                     register(mAttachedViews.get(0).getContext());
523                 }
524             }
525         }
526     }
527 
toLocalDateTime(long timeMillis, ZoneId zoneId)528     private static LocalDateTime toLocalDateTime(long timeMillis, ZoneId zoneId) {
529         // java.time types like LocalDateTime / Instant can support the full range of "long millis"
530         // with room to spare so we do not need to worry about overflow / underflow and the rsulting
531         // exceptions while the input to this class is a long.
532         Instant instant = Instant.ofEpochMilli(timeMillis);
533         return LocalDateTime.ofInstant(instant, zoneId);
534     }
535 
toEpochMillis(LocalDateTime time, ZoneId zoneId)536     private static long toEpochMillis(LocalDateTime time, ZoneId zoneId) {
537         Instant instant = time.toInstant(zoneId.getRules().getOffset(time));
538         return instant.toEpochMilli();
539     }
540 }
541