Passing parameters by reference

[jawahar]

Hi,
From the Beginners Guide, I understand that in B4A, the parameters are transmitted by value and not by reference(section14.5.5 - Parameters).
In VB, when I needed to return more than one parameter to the calling function I used to use ByRef. How can I do that in B4A? I understand that if I use a Non-Primitive then this is possible but what about primitives.....

For example in VB6 a simple swap would be

Public Swap(Byref A as Long, Byref B as Long)
Dim C as Long
C = A: A = B: B = C
End Sub

Thanks & regards,

Jawahar

 

[agraham]

Java, and hence Basic4android, does not support passing by reference. To return multiple items you can pass an array and assign the array elements in your Sub.

 

[Erel]

Two options:
- Pass an array of one element:

Public Swap (A() As Long, B() As Long)
 Dim C As Long = A(0)
 A(0) = B(0)
 B(0) = C
End Sub

Declare a Type that wraps the actual value and pass the type:

Type LongWrapper (val As Long)