While loop to reduce int in android

Question

I'm trying to take an int from SharedPreferences that tracks how long the app program has been active and reduce it to an int less than 7 to show what day of that program week the user is in.

Here is what I have used to reduce the int, (i am trying to use a while loop to go in and subtract 7 until the int is less than 7. The IF statement was added to see if the int was reduced and it was displaying the wrong String)

public void methodNameHere() {
        SharedPreferences onvalue = getApplicationContext().getSharedPreferences("TRAININGDAY", MODE_APPEND);
        int day = (int) onvalue.getLong("DAY", 0);
        SharedPreferences.Editor edit = onvalue.edit();

        while (day < 7) {
            day = day - 7;
        }

        if (day < 7) {
            String da = Integer.toString(day);
            Toast.makeText(CardioStart.this, da, Toast.LENGTH_LONG).show();
        } else {
            Toast.makeText(CardioStart.this, "f?*k", Toast.LENGTH_LONG).show();
        }
    }

And this is where the int is coming from:

private void dayOfTraining() {

        TextView day = (TextView) findViewById(R.id.dayoftraining);
        date.setTimeInMillis(millidate);

        Calendar someday = Calendar.getInstance();
        someday.set(2015, 4, 25);

        Calendar today = Calendar.getInstance();
        Long millidate = someday.getTimeInMillis();
        long timeTwo = today.getTimeInMillis();
        long oneDay = 1000 * 60 * 60 * 24;
        long delta = (timeTwo - millidate) / oneDay;
        long actualday = delta + 1;
        day.setText(Long.toString(actualday));

        SharedPreferences onvalue = getApplicationContext().getSharedPreferences("TRAININGDAY", MODE_APPEND);
        SharedPreferences.Editor edit = onvalue.edit();
        edit.putLong("DAY", actualday);
        edit.commit();

    }

String da toasts as "29" so it seems its not reducing.

I feel like I am missing something simple or I just don't have a true grasp on the use of while loops. Any help would be greatly appreciated. Thank you.

Maybe you should learn what the modulo operator (%) is and does... — Durandal, Jun 22 '15 at 17:56
`to show what day of that program week the user is in.` Do you really need all this **machinery** only `to show the current weekday`? http://stackoverflow.com/a/23266940/2649012 — Phantômaxx, Jun 23 '15 at 07:58

score 1 · Accepted Answer · answered Jun 22 '15 at 17:54

1

The while statement is wrong, you should be checking while(day > 7) -> do this not while(day < 7) . Code -

while (day > 7)
{
day = day - 7;
}

answered Jun 22 '15 at 17:54

Anand S Kumar

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Wow. Just wow. I'm a dummy. Thanks for pointing that out, and not blowing up my spot for being a dunce. Cheers! – Mike Maye Jun 22 '15 at 17:59

While loop to reduce int in android

1 Answers1