[Gambas-user] refer to an object with a string

[Doriano Blengino]

Jean-Yves F. Barbier ha scritto:
> Doriano Blengino a écrit :
>   
>> Jean-Yves F. Barbier ha scritto:
>>     
>>> Hi list,
>>>
>>> I'm trying to refer to come couples Label/CheckBox that have the same suffix
>>> (lbl_ONE & ckb_ONE) to enable/disable couple in one shot.
>>>
>>> But after building my strings that are orders, GB tell me its not an object:
>>>
>>> PUBLIC SUB lblckb_on_off(which AS String, on AS Boolean)
>>>   DIM lbl AS String
>>>   DIM ckb AS String
>>>   
>>>   lbl = "lbl_" & which & ".Enabled = "
>>>   ckb = "ckb_" & which & ".Enabled = "
>>>   IF onoff THEN   ' ON
>>>     lbl &= "TRUE"
>>>     ckb &= "TRUE"
>>>     (SOMETHING TO "EXEC" THE STRING)lbl    (or may be: (SOMETHING)lbl = TRUE)
>>>     (SOMETHING TO "EXEC" THE STRING)ckb
>>>   ENDIF 
>>> END 
>>>
>>> Is there a way to do that?
>>>   
>>>       
>> The EVAL statement, but I never used it and also I am not sure it exists 
>> in gambas2.
>>     
>
> Yes it exists, however I'm not tough enough to tell if it can work that way
>
>   
>> But there are other ways, more efficient. One is to find object handlers 
>> using introspection. You can find all the children of a form and, based 
>> on their name, do things (you can also scan all the children and, when 
>> you find the one which has the right name, do the thing you want). The 
>>     
>
> I don't see (may be you're talking about iterating form content is a Variant)
>   

The following is a routine which transfers data from a form (or other 
container) to a record of a database.
The gadgets which are operated on are named like "edDBxxxx", where 
"xxxx" is the name of the field in the database.
This routine manages textboxes, checkboxes and other; i attach it 
because you can see how to walk in a form,
get the names and operate on gadgets:

    ' transfers a record from page to database; TRUE if error
    PUBLIC SUB save_record(hCont AS Container, recmod AS Result) AS Boolean
      DIM obj AS Object
      DIM st AS String

      FOR EACH obj IN hCont.Children
        IF obj.name LIKE "edDB*" THEN
          SELECT Lower(object.Type(obj))
            CASE "textbox", "tdbsimplebox"
            recmod[Mid(obj.name, 5)] = obj.text

            CASE "tdbcalcbox"
            recmod[Mid(obj.name, 5)] = utils.formatted2float(obj.text)

            CASE "tdbdatebox"
            st = canonicaldate(obj.text)
            IF st <> "" THEN recmod[Mid(obj.name, 5)] = Val(st)
           
            CASE "checkbox"
            recmod[Mid(obj.name, 5)] = obj.value

          END SELECT
        ENDIF
      NEXT
      recmod.Update
      RETURN FALSE

      CATCH
      Message.Error("Error " & error.Text & " in " & error.Where)
      RETURN TRUE
    END


>> other one, which I would recommed, is to create dynamically you objects, 
>> especially if they are many, and keep a reference to them using arrays 
>> or collections. Or a mix of the two: you create a form visually in the 
>> IDE, then in a routine collect all the handlers, and from then on you 
>> always use those handlers. I suspect you are doing something very large...
>>     
>
> No, in fact, not that big.
> On 2nd thought, it wasn't a good idea (even if it has worked, code would have
> been beeing too much obscur)
>   
I saw a "Label2572"... it seemed to me a little strange...
And about obscure code, I think that well commented (and written!) code 
is never obscure, but sometimes one writes code too much complex for the 
purpose that has to be done. I sometimes do that...

Re-regards,

-- 
Doriano Blengino

"Listen twice before you speak.
This is why we have two ears, but only one mouth."