LIST SELECTION

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Illustration

Digi-Map 2002 [1] for PalmOS uses list selection in combination with text entry to let users choose a location.

Context

…you want to provide versatile and easy to use functions to support users in entering DEPARTURE AND DESTINATION as well as INTERSTATIONS.

Problem statement

How can users communicate a location to the system without cumbersomely entering address information or selecting locations on a map?

Problem description with forces

Addresses that can be navigated to are stored in a database that describes the interactive map. These available addresses can be presented easily to users in a list to allow them selecting the desired location directly if available. This ensures that users do not enter addresses that do not exist in the database. Instead users can view which locations are available for navigation at a glance.

However, the address data of a whole map build a large list that is cumbersome to scroll through. So mechanisms are needed with which users can preliminary select the initial letter of the street or a district of a city for example.

Examples

As shown in the opening picture, Digi-Map 2002 for PalmOS uses list selection in combination with text entry to allow users choosing a location. This makes it easy and fast to find a street in the relatively long list. Unfortunately, the text entry is not very fault-tolerant.

In Destinator 2.0 [2] there are different possibilities to make a preliminary selection to limit the number of addresses in the list. Users can either select a city or zip code first and after that a street name or - what makes not really sense - a street name first and after that a city or zip code (a street always belongs to one city. So selecting this city is one unnecessary step users have to take).

The lists can be displayed with or without a combination of text entry.

Unfortunately the on-screen keyboard takes up too much screen space and makes scrolling the list even harder.

Solution

Therefore:

Allow users to select locations like departure, destination or interstations out of a list of available addresses or street names (with house number if necessary) directly.

If this list gets too large to scroll through easily (which is probable) provide means with which users can make preliminary selections. For example, combine list selection with text entry. If a user enters a letter, list all addresses that start with this letter. Another possibility is to let users choose a city district, zip code or a region in the map. List only addresses contained in this area.

Diagram

References

List selection is mostly used in combination with TEXT ENTRY.

Literature and Links

1. Digi-Map 2002, Demo-Version 2.25; http://www.digi-map.de <LI>Destinator Version 2.0.06Fx; http://www.destinator.de </OL>