A tool for alphanumeric free-text input is required.

Context

Operators need to enter alphanumeric free-text, e.g., when composing a message.

Forces

On screens not supporting multi-touch the CAPS key cannot be used. Instead, a CAPS LOCK functionality must be used to enter capital letters.

Solution

The solution provides an almost fully featured keyboard with multi-language support.

• All keys have a repeat function. The first repeated key press shall occur after a delay of 300 ms, each subsequent key press shall have a delay of 100 ms.
• Pressing the backspace key once shall delete the character left to the cursor. Pressing and holding it for more than one second shall delete the entire field contents.
• The Backspace key is not available if the associated field is empty.
• Pressing the shift key switches the keyboard to capital characters. The Shift key is highlighted and the labels of all keys are updated accordingly. Pressing the Shift key again switches back to lower case.
• Arrow keys move the cursor around in the associated field. In single line fields, up and down arrows are not available.
• They keyboard is designed to support multiple languages.

Example

The keyboard is designed to support multiple languages. The tables below show the keyboard layouts for a Swiss multi-language keyboard supporting German, French, and Italian.

Swiss French, lowercase

Swiss French, uppercase

Italian, lowercase

Italian, uppercase

To extend the keyboard layout to further languages, the following template can be used:

Safety impact

Free-text input should be used with care because on-screen keyboards are not as efficient as hardware keyboard because they lack tactile feedback and response time.

Usability impact

Using this pattern enables users to input short sequences of free text. To lessen the cognitive load of typing and to reduce the error rate, typing tools should be provided, e.g., dictionary-based text input support.

Your opinion

Feel free to provide your comments, reports of usage of this pattern, or feedback in general!