Scrolling Lists (HI Guide)

Inside Macintosh: Macintosh Human Interface Guidelines / Part 2 - The Interface Elements: Chapter 7 - Controls / Other Elements for User Interaction

Scrolling Lists

A scrolling list is a combination of two other elements. One part of the scrolling list is a list of items, such as a list of document names in the standard file dialog box. The other component is a scroll bar, which allows the user to look at more items in the list that aren't currently visible. The size of the box that displays the list often depends on the amount of space available in the context. The list can contain as many items as necessary. Figure 7-20 shows an example of a scrolling list.

Figure 7-20 A scrolling list

When you create the list of items in a scrolling list, you may find text that is too long to fit in the list. When this is the case, it's best to eliminate text in the middle of the name and insert ellipsis points there, preserving the beginning and ending of the item's name. Users often add version numbers to the end of their document or device names, so if you cut off the end of the text item, they lose that context and must guess which of the several item names that begin the same is the desired one.

The user can click an item in the list to select it, or use multiple selection techniques such as the Shift-click combination to select more than one item. The user can also scroll through the list to peruse its contents without selecting anything. If the list contains folders, the user can use standard techniques to open them and see their contents. Users can also use the keyboard navigation techniques discussed in "Keyboard Navigation in Dialog Boxes" on page 195 in Chapter 6, "Dialog Boxes," to select items in a scrolling list.

Scrolling lists are not appropriate to use for providing choices in a limited range. Since the full range isn't visible all at once in a scrolling list, it's difficult for users to understand the scope of their choices. Sliders work very well for displaying a limited range of values and for letting users choose their preference in the range. Sliders are described in the section "Sliders" on page 213.