Tip controlling the user interface on a mobile representation

In some cases, you may need to manage the following situation:
* A first field (for example, a combo box) has a choice that requires the input of additional information.
* For all other choices, the additional information is not relevant.

For example: on a shipment of goods by boat, a country name and designation must be entered to indicate the country where the goods are located in order to be loaded on the boat. The input page might look like the following example:

Boarding country : [ ] Sender country     [ ] Recipient country    [ ] Other country
                                                                   [ enter country here ]

If you want to enter the country name only if the Other country check box is selected, you can do the following:

• Set the Read only attribute on the country code if the Sender country or Recipient country check boxes have been selected.
• Propagate the modifications done on the Boarding country choice when the first two choices are made.

it is important to understand that all the actions that dynamically hide or disable fields in the user interface will not work on a mobile represenation because there is no real time exchange on every field, but a "page like" input with validation at the end.

In all cases, the control must be done at the class level. On a mobile representation, you can:

• Define three links to force an exchange when clicking them and automatically assign the country code of your choice or propose an input.
• Consider that the country can always be entered and updated when the page is sent.

What is important is that you ensure that the rule is controlled at the class level. On every representation based in the used device, you can create more interactive rules to help the user.