An application user interface (UI) serves two main purposes: to receive user input and to provide user output. How well your application handles these tasks depends on the target hardware platform capabilities, operating system (OS) configuration, and input/output (I/O) requirements.

Before designing your application, you need to ask some important questions about its interface:

• Will it include graphics?
• How will your application receive user input?
• Will users enter commands with a keyboard, with a touch screen, with voice commands, or with buttons on a console?
• How will you provide feedback to the user?
• Will your device support an LCD screen or audio feedback?

  The Windows CE OS supports a range of devices, from the Handheld PC (H/PC)to embedded systems. Its modular feature design enables you to create applications that are suited for a specific platform. Because UI requirements vary, this section describes general design considerations for a graphical UI.

  A well-designed UI focuses on users and their tasks. Good UI design considers general design principles as well as how graphics, color, and layout influence application usability. Consider the following design concepts when creating a user-focused UI:

  • Give the user control

    Enable the user, not the computer or software, to initiate actions. Remember, the goal of the user is not to use the application, but to accomplish a task.

  • Use familiar concepts

    To increase familiarity with the interface, enable users to manipulate representations of the tasks they perform. For example, if you provide a desktop-like interface, enable users to drag icons depicting documents to an icon depicting a trash can when deleting a file. For other types of interfaces, be sure that buttons and icons relate to the tasks they perform. For example, display a wrench icon to start an automotive maintenance application.

    Another way to increase user familiarity with the interface is to avoid using modes. Modes, which occur when identical commands or keystrokes perform different actions in different situations, force users to think about how the application works instead of the task at hand. Though modes are best avoided, warning boxes and message boxes are two necessary and appropriate mode types.

  • Be consistent

    Consistency makes the interface familiar and predictable, which reduces user errors and improves performance. Consistency is enhanced with components that have a similar appearance and behavior and with actions that have the same result regardless of context. For example, in a desktop environment, scroll bars operate the same way, whether the scroll bar is in a list box or window. To achieve consistency, reuse standard commands in each task.

  • Enable interactive discovery

    Empower the user to explore the interface through trial and error, but provide warnings about potential damage to the system or data. To minimize user problems, provide clear error messages and indicate appropriate actions to recover from an error. When possible, make actions reversible or recoverable.

  • Provide feedback

    Present the user with timely visual and audio cues to confirm that the software is responding to input.

  • Focus on aesthetics

    An attractive interface helps the user select appropriate information and suggests a quality application.

  • Design with simplicity

    Simple interfaces, with an uncluttered display, are easy to learn and use. Show the most important controls directly on the interface and hide the rest in menus. Reduce the number of tasks presented in a single window or screen and group related tasks together.

  • Support multiple input methods

    Provide multiple methods for performing an operation. To accomplish this, support multiple input devices if possible, and provide keyboard shortcuts or accelerators for specific tasks, if a keyboard is supported.
    

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     Last updated on Friday, April 02, 2004

    © 2004 Microsoft Corporation. All rights reserved.