New answers tagged multi-selection
Your best bet here is accordions, cases like yours are exactly the reason why they were created. I did a super quick mockup (so obviosuly there are more countries in Africa, just assume I listed them all) in which you can see the logic: 1. Display accordion // 1.2 Display ALL or Customize // 1.3 if ALL=true ('add all countries in this panel') ...
You can do this with a roll-your-own solution. To the user it looks like a drop-down; he selects it and there is a place to enter text as well as the drop-down. download bmml source – Wireframes created with Balsamiq Mockups
I would use a different bolding (as you did) but posting the information below the city to make it stand out from the heading city. Like this: download bmml source – Wireframes created with Balsamiq Mockups It would also be rendered better on mobile devices since the columns doesn't have to be that wide as in your suggestion.
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