There are situations when the form should show two select boxes in the parent - child style. For example when in the parent select box user selects country the child select should show cities only of that country.
There are at least two approaches to update child select box:
- load all cities and update contents of child select box by javascript filter;
- load cities from server on each change of country.
While the first one is simple it could be not the optimal solution for big arrays of data. Current tutorial will show how to make the second one with CapePHP.