java - 安卓 : How can I convert a Time with am and pm format into integer seconds

Question

我的数据库中有一个时间格式为“10:40 AM”的值，现在我要将它用于警报管理器，这是我的警报管理器代码。

Long alertTimeCatcher = new GregorianCalendar().getTimeInMillis()+10*1000;

+10*1000 我想用“10:40 AM”将里面的 10 更改为双引号，因此我要将其转换为整数。我该怎么做？

假设我有“上午 11:40” 我将其转换为整数

int 时间 = "11:40 AM";

这是原来的代码

Long alertTimeCatcher = new GregorianCalendar().getTimeInMillis()+10*1000;

那么这就是我需要的

Long alertTimeCatcher = new GregorianCalendar().getTimeInMillis()+Time*1000;

因此，为了触发我的闹钟管理器，我需要将时间转换为整数。

这是我到目前为止所尝试过的。

try {
        Cursor c = myDB.rawQuery("SELECT * FROM " + "tblEvents", null);


        int Column2 = c.getColumnIndex("Date");
        int Column3 = c.getColumnIndex("Time");

        String[] arr = new String[0];
        // Check if our result was valid.
        ArrayList<String> list = new ArrayList<String>();
        c.moveToFirst();
        if (c != null) {
            // Loop through all Results
            do {
                String Date = c.getString(Column2);
                String Time = c.getString(Column3);
                Calendar ca = Calendar.getInstance();
                SimpleDateFormat df = new SimpleDateFormat("M/dd/yyyy");
                String formattedDate = df.format(ca.getTime());


                if (Date.equalsIgnoreCase(formattedDate)) {
                    list.add(Time);

                    Toast.makeText(getApplicationContext(), "Converter : ", Toast.LENGTH_SHORT).show();
                }
            } while (c.moveToNext());
        }
        Collections.reverse(list);
    }catch(CursorIndexOutOfBoundsException e){
        e.printStackTrace();
    }
    Long alertTimeCatcher = new GregorianCalendar().getTimeInMillis()+10*1000;

    Toast.makeText(getApplicationContext(),alertTimeCatcher.toString(),Toast.LENGTH_SHORT).show();

    Intent alertIntent = new Intent(this,AlertReceiver.class);
    AlarmManager alarmManager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
    alarmManager.set(AlarmManager.RTC_WAKEUP,alertTimeCatcher,PendingIntent.getBroadcast(this,1,alertIntent,PendingIntent.FLAG_UPDATE_CURRENT));

Answer 1

您可以使用 SimpleDateFormat将 String 转换为 Date

String myStringDate = "10:40 PM"
SimpleDateFormat sdf = new SimpleDateFormat("hh:mm aa");
Date myDate = sdf.parse(myStringDate);

然后获取以毫秒为单位的时间并将其替换到您的查询中:

Calendar calendar = Calendar.getIstance();
calendar.setTime(myDate);
int hourToSeconds = calendar.get(Calendar.HOUR_OF_DAY) * 60 * 60;
int minutesToSeconds = calendar.get(Calendar.MINUTE) * 60;

int totalSeconds = hourToSeconds + minutesToSeconds ;
Long alertTimeCatcher = new GregorianCalendar().getTimeInMillis()+ totalSeconds *1000;