Android Question read data from a JavaObject array

[Pesciolina]

how can I read the tagID field ??

Thanks
Marco

Sub onCAENRFIDNotifyTag_Event (MethodName As String, Args() As Object) As Object
    Dim results As JavaObject = Args(0)
    Dim nTag As Int
            
    Try
        
        Dim CAENRFIDNotifyList As List = results.RunMethod("getData",Null)
        For Each CAENRFIDNotify As JavaObject In CAENRFIDNotifyList
            'Todo something with the JavaObject CAENRFIDNotify'
            nTag = nTag + 1
            Log("Number of Tags received: " & nTag)
            
        Next
        
        Return Null
        
    Catch
        Return Null
        Log(LastException)
    End Try
    
End Sub

 

[drgottjr]

speaking for myself, it would be much easier if you could post the actual json string or the url where i can get it myself. i know we have a json pretty print, but it's not something i use.

 

[Pesciolina]

the data come from an RDIF reader
I took another small step
it goes wrong when I assign the index 0

Dim TagIdArray As List = CAENRFIDNotify.RunMethod("getTagID", Null)
            
            Dim TagID_0 As Byte
            TagID_0 = TagIdArray.Get(0)

 

[JordiCP]

Just to try, does it work?

Dim TagIdArray() As Byte = CAENRFIDNotify.RunMethod("getTagID", Null)

 

[drgottjr]

sorry, i misread javaobject array for json array. beyond my realm of interest, but in looking at the java code, it seems like your TagIdArray list is not a list of byte. have you looked at the source (https://github.com/Maurizio-M/app-r...m/radio6ense/radioScan/InventoryActivity.java)?

you say "it goes wrong", but you didn't say if you got an error. did you? what was it? you might want to wrap your get() call in a try/catch block, and if you get an error, see what it is. i think your "Dim TagID_0 As Byte" declaration should be another (java)object. the java code itself, seems relatively clear enough for someone familiar with CAENRFIDN, which, regrettably, excludes me. sorry.

 

[drgottjr]

jordicp working late tonight!

 

[JordiCP]

jordicp working late tonight!

Was just about to close my laptop, but couldn't resist a quick look at the forum ?

 

[drgottjr]

like i say, i thought it was about json. but i definitely defer to the master in device electronics. carry on!

 

[DonManfred]

it goes wrong when I assign the index 0

Based on the screenshot i would guess you need to get elementData from the List and then get item 0 of elementData. You should then find tagID Array

 

[OliverA]

getTagId returns a Byte array, not a list. Source: http://www.semiconductorstore.com/pdf/NewSite/CAEN/CAEN_RFID_API_Reference_Manual_rev_05.pdf#page81

 

[drgottjr]

yeah, according to the java source, tagID is an array of Byte, so just step through it 0 to array.length - 1

 

[Pesciolina]

thanks to you I have progressed in development. It is nice to know that there is always someone who can help you