java - 我的闹钟应用程序不会显示闹钟通知或播放闹钟声音？

Question

我正在使用 AlarmManager 来发出警报。我不确定为什么它不起作用，请随时索取更多代码。预先感谢您。

MainActivity.java

button.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
                @Override
                public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {
                    if (isChecked) {
                        alarmMgr = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
                        Intent intent = new Intent(MainActivity.this, AlarmReceiver.class);
                        Calendar calendar = Calendar.getInstance();
                        calendar.setTimeInMillis(System.currentTimeMillis());
                        int y = calendar.get(Calendar.YEAR);
                        int mon = calendar.get(Calendar.MONTH);
                        int d = calendar.get(Calendar.DAY_OF_MONTH);
                        if (ampm.equals("pm")){
                            h=h+12;
                        }
                        calendar.set(y, mon, d, h, m);
                        alarmIntent =PendingIntent.getBroadcast(MainActivity.this, 0, intent, 0);
                        alarmMgr.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), 1000 * 60 * intervalMinute, alarmIntent);
                    } else {
                        if (alarmMgr!=null) {
                            alarmMgr.cancel(alarmIntent);
                        }
                    }

没有错误。

Answer 1

setRepeating 相当于 API 级别 19+ 上的 setInexactRepeating。来自文档:

Note: as of API 19, all repeating alarms are inexact. If your application needs precise delivery times then it must use one-time exact alarms, rescheduling each time as described above. Legacy applications whose targetSdkVersion is earlier than API 19 will continue to have all of their alarms, including repeating alarms, treated as exact.

您需要根据您的目标 API 级别调用 set、setExact 或(可能)setAlarmInfo，并手动安排重复警报。

此外，请仔细检查您设置下一个闹钟时间的逻辑，因为现在对我来说它看起来过于复杂。你可以这样做:

final Calendar c = Calendar.getInstance();
c.add(1, Calendar.DAY_OF_MONTH); //Just an example
alarmMgr.setExact(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), alarmIntent);

我在 GitHub 上发布了一个闹钟应用程序，它也可能有用 ( link )。