How do I achieve multiselection with a list or checkbox

Please, how do i achieve this type of multiselection as shown in the attachments.

I want the user to be able to select more than one option, and note that each option has some children that should be displayed. Also the number of options is dynamic. Not necessarily 5 through out, it could change depending on a variable.

Bump

I,ve never used this lists but my Idea would be to spawn/update a list depending on what your mouse cursor is above. Like on your second image, Mouse is over NavigationItem3 on dropdown1, so have your dropdownlist2 set to visible(or spawn it), update its position to navigationItem3Y and navigationItem3+navitaionItem.width, update it's values accordingly. Hardest part would be preparing all the values, you can use arrays and a xml/json file with all the info.

caiorosisca, I'll try it out, thanks. But i guess it should work, with some other ideas i can input

I,ve never used this lists but my Idea would be to spawn/update a list depending on what your mouse cursor is above. Like on your second image, Mouse is over NavigationItem3 on dropdown1, so have your dropdownlist2 set to visible(or spawn it), update its position to navigationItem3Y and navigationItem3+navitaionItem.width, update it's values accordingly. Hardest part would be preparing all the values, you can use arrays and a xml/json file with all the info.