Put the code in a clock timer.
How are you storing the latitude and longitude?
It would really help others to help you if you posted an image of your relevant blocks and your firebase data.
Okay will try this
Using gps module
Introduce a clock timer. On first click of your button you will be taken to the location, then you start the clock timer at the same time. Every interval (e.g. 1 minute, 5 minutes) the location will be checked again. If the lat/lon coordinates have changed, the map will change.
Thank you so much but is there any chance to display the data without clicking the button?
You can start the clock/run the button procedure in Screen.Initialise, or have another clock timer start it.
Note, this will only work while the app is open, the clock will eventually stop if the app moves into the background
means it wont display data if we close the app?
Correct. But if the app is closed, it cannot display the data, can it ?
that is what I'm wondering
To get the data while the app is closed, you may need a background tasks extension and a notification extension to send the data to the device
how do i do that? 
I'm sorry that I'm asking too many questions... still a beginner for this app.
- BackgroundTasks Extension by Atom_Developer (25 USD)
- Notification Stype Extension by jarlissonlira2 with various types of notifications
Hi...I want retrieve the value under "detect". If the value is 1, it means the power cable is cut...so the app sends warning through call.
At the same time, i want the app keep updating the data with date and time. And i keep getting as image below.
Becuase you are taking the label text and comparing
what should i take then?
can you please continue the talk as i also want to get value from firebase in background.