Assigning group upon registration

[aklisiewicz]

I want to assign user to certain group upon registration. For example I would have groups: SILVER , GOLD , PLATINIUM
When user registers I want to allow him to select one of the groups from the list. Since Joomla creates several other default groups I have to choices:
- creating those 3 groups a part of REGISTERED group and use it
- creating another CUSTOM FIELD allowing those 3 entries and allow user to select from the dropdown upon registering
- ...perhaps there is another solution which I'm not aware of
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Based on the group criteria I want to grant access to certain data (or not). I know I can use build int Joomla groups for all this, but the problem is that I want the USER decide which group he picks when registering not the admin assigning user later on to specific group.

What is the best method to implement it ?

[AMurray]

I don't believe the core system can allow that, the default is basically, Registered, and the site admin would then allocate the user to any other group(s).

That said, this extension would do what you want.
https://extensions.joomla.org/extension ... -selector/

(Note this is a few years old (last update on JED is 2015) so it may not work for much longer in most recent J3.x (including 3.10 upcoming). You may find updated versions on the vendors website directly but I can't post that URL here. Visiting their site I can see a v2.0.5 (2017) for the Usergroup Selector plugin.

There may be others too, but again varying ages or non-active development (and a mix of free/commercial)
https://extensions.joomla.org/category/ ... anagement/

I don't know of any other way to do it unless you write a custom plugin.