for example in database i have country and city of that country and I want create a expander or anything like expander that can help me for group content that is like expander (hide and show data) that have country name and in expander I want add every city in that country. how to do that?
What I have tried:
Since I don't know how to do it i don't tried anything. I search about it and can't find anything that can help me.