Queries are used in situations with more than one ways to proceed, when the application needs data from the user, or when it is necessary to make sure the user knows what is happening. A query must be exited before the application can proceed.
Queries are displayed in pop-up windows. The following query types can be used:
- Confirmation query: a question or notice with one or two possible responses.
- List query: a question with a selection of more than two possible (predefined) responses.
- Multi-selection List query: presents a list of items; the user can select any number of them.
- Data query: used for numeric or textual input.
- Message query: used for various purposes in queries that are longer than one screen.
Some usability guidelines
- Queries should be displayed in pop-up windows.
- Queries should consist of a prompt and some kind of an input component.
- Make sure the prompt text for the Confirmation query should be giving a positive sign. Users tend to press the Selection key without thinking too much.
- For the Data query, the input field should be able to extend automatically in case the input text is more than one line.
- Activate text prediction (T9) for text input.
- The query text should be meaningful and localized.
- The user should be given help in case of a query which might be complicated to understand from user perspective.