Question

我在信标类型工作，我需要每半小时重置一次计数。当设备被触发时，我将在db中插入相应日期和时间以及计数器的数据。但是当它达到半小时后，需要从1重置计数器。如何处理？

以下是我尝试的代码。

此数据库方法将在服务类中调用..

 if(Application.getPrefString(BluetoothLeService.this,Application.ACTIVITY_LOGGING_ON).equalsIgnoreCase(getString(R.string.activity_logging_on))) {
     if(GattConstant.CHAR_ACTIVITY_NOTIFY.equals(characteristic.getUuid())) {
          Log.e("logging on", "logging on");
          dbHelper.insertTestHistory();
     }
}

DatabaseHelper：

 private int activityCounts=0;

  public void insertTestHistory() {
    synchronized (lock) {
        SimpleDateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss", Locale.getDefault());
        String date = dateFormat.format(new Date());
        previousDate = date;
        Log.e("activitycount", activityCounts + " " + date);
        activityCounts++;
                SQLiteDatabase database = this.getWritableDatabase();
                ContentValues values = new ContentValues();
                values.put(Application.ACTIVITY_LOG_STATUS, previousDate + ",activity," + (activityCounts));
                database.insert(Application.ACTIVITY_LOG_TABLE, null, values);
                database.close();
            }
        }

    public List<String> getActivityHistory() {
    synchronized (lock) {
        List<String> deviceHistoryLog = new ArrayList<String>();
        String selectQuery = "SELECT *  FROM " + Application.ACTIVITY_LOG_TABLE + " ORDER BY ROWID DESC";
        SQLiteDatabase database = this.getWritableDatabase();
        Cursor cursor = database.rawQuery(selectQuery, null);
        if (cursor.moveToFirst()) {
            do {
                deviceHistoryLog.add(cursor.getString(cursor.getColumnIndex(Application.ACTIVITY_LOG_STATUS)));
            } while (cursor.moveToNext());
        }
        // Close cursor and database.
        cursor.close();
        database.close();
        return deviceHistoryLog;
    }
}


  in MainActivity:

public class MainActivity extends Activity{
   Da
    @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_tracking);
    dbHelper = DatabaseHelper.getInstance(this);
    deviceHistory = dbHelper.getActivityHistory();
    if (deviceHistory.size() == 0) {
        Log.e("empty", "empty");
    } else {
        for (int i = 0; i < deviceHistory.size(); i++) {
            historyContent += deviceHistory.get(i);
            historyData = deviceHistory.get(i);
            Log.e("historydata", historyContent);
        }
    }
}

我得到的数据是：

04-28 14:41:32.730 30076-30091/com.test E/activitycount: 1 04/28/2016 14:41:32
04-28 14:41:33.861 30076-30091/com.test E/logging on: logging on
04-28 14:41:33.863 30076-30091/com.test E/activitycount: 2 04/28/2016 14:41:33
04-28 14:41:33.879 30076-30091/com.test E/logging on: logging on
04-28 14:41:33.881 30076-30091/com.test E/activitycount: 3 04/28/2016 14:41:33
04-28 14:41:33.895 30076-30091/com.test E/logging on: logging on
04-28 14:41:33.896 30076-30091/com.test E/activitycount: 4 04/28/2016 14:41:33

当它达到15:01时我需要重置，即触发时活动记录为1。然后15.02为2，依此类推，每半小时一次，反击重置。

Answer 1

您可以使用AlarmManager

AlarmManager alarm = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
Intent notifyintent = new Intent(this, NotificationBroadcast.class);
pIntent = PendingIntent.getBroadcast(this, 0, notifyintent, 0);

Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
//update 30 seconds
alarm.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),1*30*1000, pIntent);

并使用广播接收器更新计数

public class NotificationBroadcast extends BroadcastReceiver {  

    @Override
    public void onReceive(final Context context, final Intent intent) {
       ....
   }
}

Answer 2

<强> 1 即可。维持上一个重置时间的类级字段，以毫秒为单位

long lastResetTimeInMilliSecs = new Date（）。getTime（）/ 1000;

制作一个计时器，以便在30分钟后重置activityCounts

<div class="container">
    <div class="row">
        <div class="col-sm-6">
            <!-- left column -->
        </div>
        <div class="col-sm-6">
            <!-- right column -->
        </div>
    </div>
</div>

}

您的方法是这样的，不要将计时器逻辑与此方法混合

<div class="container">
    <div class="row">
        <div class="col-sm-6">

            <!-- left column -->
            <div class="row"><!-- Nested Row. Children columns add up to 12 -->
                <div class="col-sm-7">
                    7/12 of the left side
                </div>
                <div class="col-sm-5">
                    5/12 of the left side
                </div>
            </div>

        </div>
        <div class="col-sm-6">
            <!-- right column -->
        </div>
    </div>
</div>

启动计时器一次，即调用startResetTimer方法一次，每次调用insertTestHistory时都不需要调用它

如何基于android的日期和时间每半小时重置一次计数？

2 个答案: