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Illustration

In the ToDo-list application in Palm OS, ToDo-items can be assigned to categories

Context

…you want to decide how data in your mobile application should be organized and how users can navigate through this data - INFORMATION ARCHITECTURE AND NAVIGATION.

Now you want to organize users' documents or let them organize their documents themselves - USER CUSTOMIZATION.

Problem statement

How can you organize the user's data respectively let users organize their data themselves?

Problem description with forces

You can divide up your dialogs across multiple screens and you can use scrolling to get around long linear documents.

Applications, however, mostly contain lots of user data arranged as separate named items in a list. Users need to find these individual items. Sometimes, however, there are too many items in the list to fit on a single screen which makes it hard to find a single item.

Although documents are often organized in hierarchical file systems, these are more difficult to manage and understand, especially for novice users. Additionally, a file system browser takes up lots of screen space and requires specials means of data representation (see TREE VIEW, PATH).

Examples

Palm organizes things (memos, addresses, to-do items) into categories (see opening picture). The categories are listed in a combo box. A user can choose which category to display, of which one is "all".

The categories themselves can be edited and customized to the users needs.

Most Palm applications provide these categories. When users start an application they are in a standard category of the one they were in last time. When the application is running, pressing the physical button that invoked this application moves users to the next category, so they can cycle through quickly or go to the popup or choose category all and use scrolling.

Agenda Fusion [1] provides different categories for appointments and tasks which can be edited using the Category Manager and Categories Icon Manager.

Category icons for tasks and appointments are displayed in the application's "month view" for example.

Solution

Therefore:

Make your application provide single-level categories to let users organize their data.

Single level categories are easy to understand, and don't need lots of space or a complex navigation to get around. The current category can be just one word in a popup menu or an icon.

Diagram

References

This is a basic pattern and has no further references in this pattern language.

Notes

This pattern was adopted from Charles Weir and James Noble [2]. It was modified to be adapted to the structure and format of this pattern language and supplemented where necessary.

Literature and Links

1. Agenda Fusion Version 5.0 for Pocket PC; http://www.developerone.com/demo/fusion5.htm <LI>Weir, C. and Noble, J. (2001): A window in your pocket - Some small patterns for user interfaces. In Proceedings of the European Conference on Pattern Languages of Program Design, EuroPloP 2001. The Hillside Group, Inc. </OL>