I want to limit my ui extension plugin (panel) to be single instance, from the source comment, I think the below 2 functions in the class should be used:
class NOVTABLE window : public extension_base
{
public:
virtual const bool get_is_single_instance() const = 0;
virtual bool is_available(const window_host_ptr & p_host) const =0;
....................
....................
};

if I override get_is_single_instance(), seems useless.
if I override is_available() and return false, the panel still can be added to the layout. how can I limit the panel to be add to the layout once?

for example, the foo_uie_albumart, once the panel of it is added to the layout, the popup menu of the layout will not list its name anymore, this is what I want.

Thanks

I haven't actually used the aforementioned class, but I'd imagine you'd want to do something like

I've tried, it just didn't even get called.

You mean this part of the source comment?


That is in regard to get_is_single_instance(). The relevant window service factories (uie::window_factory, uie::window_factory_single) implement the method, hence your overriding of it proved useless (since the factory overrided that).

So I would guess you are using the wrong factory.

thanks very much, you are right, wrong factory. I was based on other code,
so didn't realise there's classes for sing window