I want members of my website to be a member of one group only at a time, how can i do it please.
You will need a customization for this.
Something to consider before customizing Groups is to be sure you will continue to use it and not replace it with a 3PD Product.
I paid for a similar customization to SEAO's Groups/Communities Plugin. The customization limits by ML the number of groups a User may create. But I see the usefulness of your requirement.
I'd suggest for flexibility to consider adding 2 things to your idea:
1. Use an ML setting
2. Use a value instead of forcing to 1 (which you may still do of course using the value of 1). Later on you may wish to offer more memberships to higher MLs and possibly use as a monetization feature.
Also if possible, limit the code changes to the SE Groips code so future updates may be less work to implement your customization into.
Ok thanks,
What if I want them to join only one network.
You can set up networks per the tutorial and have them assigned. In that way, they can't join any other network than the one or ones you assign them to. https://support.socialengine.com/php/customer/portal/articles/1649382-admin-panel---manage->-networks
Thanks Donna, how can i add the network to sign up form so that users can select their network during registration.
You may want to choose the option to automatically assign them based on a profile question for that.
Thanks Donna I try it.