[Qgis-developer] Plugin Development C++ Windows - Any response?

[Barend Gehrels]

On 27-2-2011 22:01, Martin Dobias wrote:
> On Sat, Feb 26, 2011 at 12:52 PM, Barend Gehrels<barend at xs4all.nl>  wrote:
>>>> I can imagine the API is not binary compatible for some upgrades (usually
>>>> it
>>>> is extended so then still compatible, depending on the model used). Is
>>>> there
>>>> not a mechanism to check if a plugin corresponds to the version of the
>>>> host
>>>> (qgis)? I think this is feasable...
>>> Yes the version is available within the QGIS namespace: QGis::QGIS_VERSION
>> What I mean is this: adding one method to QgisPlugin, e.g.:
>> virtual int interfaceVersion() = 0;
>>
>> which gives back a interface_version_number. That number only changes if the
>> (plugin) interface changes. QGis can check if the plugin does implement the
>> right interface.
>>
>> But I now understand better that if the plugin calls back the qgis API, also
>> that interface has to be stable. So in practice this will indeed change with
>> every version. But anyway, even then, qgis can check that number as its
>> first action and discard that plugin if the interface_version_number is
>> wrong.
> Exactly. This is something that should be added and checked in order
> to avoid possible crashes after upgrades. Even better would be to make
> it a global function in each plugin since that would avoid creation of
> a new instance of that plugin which could actually make some calls to
> qgis api. I would call that method e.g. 'requiredQgisVersion' and it
> would always QGis::QGIS_VERSION - i.e. version of qgis used when
> compiling the plugin.
>
>

Sounds perfect to me.

Regards, Barend



-- 
Barend Gehrels
http://about.me/barendgehrels