如何根据日期和时间android每半小时重置一次计数？

Question

我正在使用信标类型，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。但是到了半小时后，需要将计数器从1重新设置。如何处理？

这是我尝试过的代码。

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();
     }
}

数据库助手：

 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

当它到达 15:01 时我需要重置，即当它触发时活动记录为 1.. 然后 15.02 为 2 以此类推，每半小时，计数器重置一次。

Answer 1

你可以使用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

1。以毫秒为单位维护上次重置时间的类级别字段

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

1. 制作一个计时器以在 30 分钟后重置 activityCounts

   public void startResetTimer() {
     new Timer ().schedule (new TimerTask () {
      @Override
      public void run () {
   
       ((BaseActivity) context).runOnUiThread (new Runnable () {
           @Override
           public void run () {
   
               try {
                   long differenceInSeconds = (new Date().getTime() - lastResetTime) / 1000;  //divide by 1000 to get time in seconds
                   if(differenceInSeconds >= 30 * 60 * differenceInSeconds) {  //30 mins = hours (multiple by 60 to convert into minutes) = 30minutes
                       //resetCounter;
                       activityCounts = 0;
                       //update last reset time 
                       lastResetTime = new Date ().getTime();
                   }
               }
               catch (Exception e) {
                   e.printStackTrace ();
               }
           }
       });
   }
   
   }, 0, 1000);
   

   }

2. 你的方法是这样的，不要把定时器逻辑和这个方法混在一起

   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(VALRTApplication.ACTIVITY_LOG_STATUS, previousDate + ",activity," + (activityCounts));
       database.insert(VALRTApplication.ACTIVITY_LOG_TABLE, null, values);
       database.close();
     }
   }
   

3. 只启动一次定时器，即调用一次startResetTimer方法，无需每次调用​​insertTestHistory时调用