[Qt-interest] QVariant is great, make it better

[Mildred Ki'Lya]

On 07/08/2009 01:06 PM, Thiago Macieira wrote:
> Mildred Ki'Lya wrote:
>   
>> QVariant IPv4::qvariantToType(QVariant::Type t); // convert this to a
>> QVariant of type t
>> QVariant IPv4::qvariantFromValue(QVariant origin); // convert origin to
>> an IPv4 QVariant
>>
>> Well, that could be done outside the QVariant class, but it would be
>> really great I think if there was some functionnality like this.
>>     
> Hi Mildred
>
> This is something I've tried to do, but I haven't been able to get the 
> template-magic to work.

Hi,

Well, I needed it, so I did it. And no need for templates. Here is my code.

It's not perfect, especially since I'm using QVariant::data() which
returns me a pointer on the value held in the QVariant, and I don't
think this is a public interface. And since QVariant::data() returns a
void*, there is no way to cast it back to QObject* so we could use
qobject_cast.

My solution: have a static variable which is a set of every value
created, and test the pointer returned by QVariant::data() with the
content of the set to determine if the value can be casted back to QObject.


:)

Mildred


-- 
Mildred Ki'Lya
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