[Interest] Design of 'pluginable' application

[Graham Labdon]

Hi
Thanks for your reply

I will need the flexibility that any plugin can talk to any other which is why I suggested the approach, but I cannot see an alternative.

I will look into QCreator

Thanks 
-----Original Message-----
From: Koehne Kai [mailto:Kai.Koehne at digia.com] 
Sent: 27 May 2014 09:04
To: Graham Labdon; Interest at qt-project.org
Subject: RE: Design of 'pluginable' application



> -----Original Message-----
> From: interest-bounces+kai.koehne=digia.com at qt-project.org
> [mailto:interest-bounces+kai.koehne=digia.com at qt-project.org] On 
> Behalf Of Graham Labdon
> Sent: Tuesday, May 27, 2014 9:41 AM
> To: Interest at qt-project.org
> Subject: [Interest] Design of 'pluginable' application
> 
> Hi
> I am designing an application built around plugins.
> I know how to create plugins and read them in at run time, but now I 
> need a way of invoking the signal/slot mechanism between them.
> For example, in a simple scenario I have plugin1 that has a slot for 
> processing a signal the plugin2 emits.
> Plugin1 knows (nor should it) nothing about plugin2.
> 
> One approach I thought of (not implemented yet) is to create a map of 
> signals and slots that a plugin defines using the QMeta System and 
> then processing these maps to create the connections. There would have 
> to be some kind of naming convention(similar to the uic connectByName).
> 
> Is this a good plan?

Do you need the flexibility that any plugin potentially talk to any other plugin, configurable at runtime? If not, the approach sounds a bit over-engineered for my taste ;) The alternative is to define some (abstract) API in a common plugin/your main executable, where one plugin implements the API, the other one uses it ...

> How is this generally implemented?

You might have a look at Qt Creator sources. It's built around plugins, and has quite some infrastructure for it (including  full Plugin Manager with a nifty 'Object Pool').

http://doc.qt.digia.com/qtcreator-extending/creating-plugins.html
http://doc.qt.digia.com/qtcreator-extending/extensionsystem-pluginmanager.html

Regards

Kai