Accurate time without sim and without internet

Question

I have an app which is used for collection all day users collecting amount normally offline and then in the evening they uploaded amount online. Sometimes there device date and time is inaccurate so they uploaded wrong data.

At the time of collection my app is getting date and time from the device. Is there any way that app always store accurate date and time without Sim and without the Internet.

If they remove battery some time device time is set as default like 1 jan 2010 etc............ — jakir hussain, Nov 07 '17 at 08:16
Are your users idiots? Why you simply not detect ie negative time skew since last app run or device restart and as user to confirm current date time? If the confirm and the time is wrong it is their problem — Marcin Orlowski, Nov 07 '17 at 08:44

score 1 · Answer 1 · edited Jun 20 '20 at 09:12

Well, before searching for an app to do this. As a human how can you tell if the date/time is correct without internet? A possible solution would be a service which counts seconds from the last time the device was connected to the internet (which means it had a correct date/time at that moment) then when you want to add the new amount you can add the seconds to the last time and store this value.

Edit

You will 2 things to achieve this:

BackgroundService
Counter which you can achieve in many ways, I would go the easy way. check this: how-to-measure-elapsed-time Or you can have an AlarmManager to do this.

One more thing You need to be careful if the device goes off or for some reason, something stopped the service. All of these are user issues and you need to decide how much you want to handle stuff for the user. You can fix user mistakes by pushing to a SqlLite database every 10~15, but this won't fix if the device went off for hours and then started again at a wrong time - I don't think there is a possible solution for this-.

score 1 · Accepted Answer · answered Mar 21 '18 at 05:15

1

You can create a Sqlite Table in application cache when user switch on data,you can save current server time in that Table and in offline mode you can compare server time with current time. this is the nearest approach to get accurate time

answered Mar 21 '18 at 05:15

Bharat Bhushan Sharma

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Accurate time without sim and without internet

2 Answers2

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