B4J Tutorial [BANano] (v7) Running Cron Jobs (in the background)

The next version of BANano (7) will have the ability to run Cron jobs!

A Cron is Timer like functionality that runs a certain job automatically at a specified time following a predifined pattern. A Cron Job is the scheduled task itself. Cron jobs can be very useful to automate repetitive tasks.

They will become especially handy together with the other new functionality, Background Workers
You could for example schedule in a Background Worker to sync your data every hour on a weekday.

cronName: Name of the Cron job. This can not be a variable and must be a literal String and can not contain spaces or special characters!

maxRuns: you can set a maximum number of times the Cron job should run (0 = indefinite, until you Stop it)

pattern: Cron jobs use a special Pattern format to define them:

* * * * * *
S M H D m d


S: second (0 - 59)
M: minute (0 - 59)
H: hour (0 - 23)
D: day of month (1 - 31)
m: month (1 - 12)
d: day of week (0 - 6), 0 to 6 are Sunday to Saturday; 7 is Sunday, the same as 0

Ranges:
Ranges are two numbers separated with a "-", and they indicate all numbers from one to the other. e.g. 10-30 would indicated all numbers between and including 10 to 30.

Interval:
A interval is a range and a number separated by "/". The range specifies the group of values, and number specifies every nth value to take from that range.
e.g. 0-10/2 would indicate every 2nd number from 0 to 10, therefore [0,2,4,6,8,10]

Example usage:
B4X:
BANano.CronStart("myCron", 15, "0 0 0 * * 2-6") ' at 00:00:00 on every weekday run, for a total of 15 times, then stop this Cron

Public Sub MyCron_Run() 
   ' do something, like a sync of your data to a server
End Sub

Public Sub btnPause_Click(event as BANanoEvent)
     BANano.CronPause("myCron")
End Sub 

Public Sub btnResume_Click(event as BANanoEvent)
     BANano.CronResume("myCron")
End Sub 

Public Sub btnStop_Click(event as BANanoEvent)
     BANano.CronStop("myCron")
End Sub

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