C H A P T E R 1 5

Controls

A search field does not need an introductory label because users recognize this control (and the magnifying glass icon) from elsewhere in Mac OS X. If you place a search field in a toolbar, however, you should supply the label “Search” to be displayed when users customize the toolbar to show icons and text or text only.

Search Field Specifications

Control sizes: Search fields are available in regular and small sizes. The height of a search field is fixed for its size, but you decide how long the control should be. The heights for each size of search field are listed below (Figure 15-75 shows a regular-size search field):

■Regular size: 22 pixels high.

■Small: 19 pixels high.

Figure 15-75 A regular-size search field

Search Field Implementation

Search field controls are available in Interface Builder. To create one using Application Kit programming interfaces, use the NSSearchField class.

Scrolling Lists

A scrolling list is a list that uses scroll bars to reveal its contents. Users can scroll through the list without selecting anything, click an item to select it, use Shift-click to select more than one contiguous item, or use Command-click for a discontinuous selection. Users can press the arrow keys to navigate through the list and can quickly select an item by typing the first few characters. You can see this behavior in a Finder window, when the Finder is in column-view mode. Each Finder-window column behaves as a scrolling list, as shown in Figure 15-81 (page 326).

Scrolling List Usage

Use a scrolling list when you need to display an arbitrarily large number of items from which users can choose. Although scrolling lists aren’t directly editable, you can provide editing functionality that allows users to provide list items you feed into the list.

Don’t use a scrolling list to provide choices in a limited range. This is because a scrolling list might not display all items at once, which can make it difficult for users to grasp the scope of their choices. If you need to display a limited range of choices, a pop-up menu (described in “Pop-Up Menus” (page 281)) might be a better choice.

Scrolling List Contents and Labeling

A scrolling list can get its contents from items you supply or from users. If an item is too long to fit in the list box, insert an ellipsis in the middle and preserve the beginning and end of the item. Users often add version numbers to the end of document names, so both the beginning and end should be visible.

Text Controls

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2008-06-09 | © 1992, 2001-2003, 2008 Apple Inc. All Rights Reserved.