software/AlarmInitReceiver.txt

/**
 * 闹钟初始化接收器，用于设置便签的闹钟提醒。
 */
public class AlarmInitReceiver extends BroadcastReceiver {

    // 查询字段
    private static final String [] PROJECTION = new String [] {
        NoteColumns.ID,        // 便签ID
        NoteColumns.ALERTED_DATE // 便签的提醒日期
    };

    // 查询字段对应的列索引
    private static final int COLUMN_ID                = 0;
    private static final int COLUMN_ALERTED_DATE      = 1;

    /**
     * 接收到广播时调用。
     * @param context 上下文对象
     * @param intent 广播时传递的Intent
     */
    @Override
    public void onReceive(Context context, Intent intent) {
        // 获取当前日期
        long currentDate = System.currentTimeMillis();
        // 查询所有未提醒且类型为便签的便签项
        Cursor c = context.getContentResolver().query(Notes.CONTENT_NOTE_URI,
                PROJECTION,
                NoteColumns.ALERTED_DATE + ">? AND " + NoteColumns.TYPE + "=" + Notes.TYPE_NOTE,
                new String[] { String.valueOf(currentDate) },
                null);

        if (c != null) {
            if (c.moveToFirst()) {
                // 遍历查询结果，为每个便签设置闹钟
                do {
                    long alertDate = c.getLong(COLUMN_ALERTED_DATE);
                    Intent sender = new Intent(context, AlarmReceiver.class);
                    // 设置闹钟接收器的数据，以便知道是哪个便签需要提醒
                    sender.setData(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, c.getLong(COLUMN_ID)));
                    PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0, sender, 0);
                    AlarmManager alermManager = (AlarmManager) context
                            .getSystemService(Context.ALARM_SERVICE);
                    // 设置闹钟，使用RTC_WAKEUP模式确保设备在提醒时间被唤醒
                    alermManager.set(AlarmManager.RTC_WAKEUP, alertDate, pendingIntent);
                } while (c.moveToNext());
            }
            c.close();
        }
    }
}