B4J Question I'm wrong

[Gianni M]

I'm wrong !! ??
the code module returns the list and map values, not the string. Why? I'm confused?

 

[MathiasM]

String values are passed By Value, List and Map are passed By Reference (just like objects)

You should change the signature of the subroutine and return the Gamma string. Like this:

Public Sub subRoutine1 (alfa As List, beta As Map) As String
    alfa.Initialize
    beta.Initialize
    '
    alfa.AddAll(Array As String("One", "Two", "Three", "Four", "Five"))
    '
    beta.Put("ciao", "Hello")
    beta.Put("mondo", "World")
    '
    Return "why doesn't the value return?"
End Sub

And then call the subroutine in your maincode this way:

gamma = demo.subRoutine1 (list1, map1)
Log(gamma)

 

[alwaysbusy]

See: https://www.b4x.com/android/forum/threads/byref-planned.59794/#post-376816

Map and List are Objects, String is immutable . You can pass a single element array:

Dim string1(1) As String
demo.subRoutine1 (list1, map1, string1)
...
Log("? " & string1(0))

demo:

Public Sub subRoutine1 (alfa As List, beta As Map, gamma() As String)
   ..
   gamma(0) = "why doesn't the value return?"
End Sub

 

[Gianni M]

String values are passed By Value, List and Map are passed By Reference (just like objects)

now, I have learned this!