storing notification ID

Solar2D General Questions/Discussion
#1

Hi there,

Im using local notifications as a sort of alarm in my app. So that I can cancel the scheduled notifications in different sessions, I would like to store the notification ID in a file. I tried using json to convert the table to string but I get the following error: 

“type ‘userdata’ is not supported by JSON”.

Has anyone encountered the same problem? Is there a way to save the NotificationID so I can use it later on in different sessions??

I’m using corona build: 2013.2100, and the code to replicate the error is the one bellow:

local futureTime = os.date( "!\*t", os.time() + 10000 ) local options = { alert = "this is the alert message", custom = {abc="custom content"}, } local notificationID = system.scheduleNotification( futureTime, options ) local json = require("json") local result,text = pcall( json.encode, notificationID) display.newText({ text=tostring(result) .. "\n" .. text, x=display.contentCenterX, y=display.contentCenterY, fontSize=30, width=display.contentWidth \* 0.8 })
#2

“userdata” is basically a C structure representing the current in-memory object.  Lua can read data values in and out of the structure, but because it’s just a memory address, there is no way to save it.  This is a frequently asked for feature, but there is currently no way to store notifications and be able to get back to them.

Rob

#3

So, if you create a system notification, there is not way to cancel it later after the user left the app?

E.g:

  1. I created a notification

  2. User quit the game

  3. User entered again in the game

  4. I need to cancel the notification because the user went back in the game again and my notification now will have no meaning

#4

Thanks for the reply Rob!

So, heres the solution Im thinking on using (if anybody comes back to this thread later):

 1. instead of storing notification ID, I will store in a file with json all information I used to create the notifications (ie. time its supposed to fire, alarm message and etc)

 2. Whenever I need to cancel a notification, even if it is only one, I will cancel them all (to cancel all I dont need their IDs)

 3. After canceling them all, I will then use the stored information to re-create all other notifications that were not meant to be cancelled.

#5

That seems reasonable.

#6

hey 

good idea!

#7

“userdata” is basically a C structure representing the current in-memory object.  Lua can read data values in and out of the structure, but because it’s just a memory address, there is no way to save it.  This is a frequently asked for feature, but there is currently no way to store notifications and be able to get back to them.

Rob

#8

So, if you create a system notification, there is not way to cancel it later after the user left the app?

E.g:

  1. I created a notification

  2. User quit the game

  3. User entered again in the game

  4. I need to cancel the notification because the user went back in the game again and my notification now will have no meaning

#9

Thanks for the reply Rob!

So, heres the solution Im thinking on using (if anybody comes back to this thread later):

 1. instead of storing notification ID, I will store in a file with json all information I used to create the notifications (ie. time its supposed to fire, alarm message and etc)

 2. Whenever I need to cancel a notification, even if it is only one, I will cancel them all (to cancel all I dont need their IDs)

 3. After canceling them all, I will then use the stored information to re-create all other notifications that were not meant to be cancelled.

#10

That seems reasonable.

#11

hey 

good idea!