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Controls

Figure 15-44 A graphical date-picker control

Date Picker Implementation

The date-picker control is available in Interface Builder. You can change the style from textual to graphical in the Attributes pane of the inspector. To create one using Application Kit programming interfaces, use the

NSDatePicker class.

Command Pop-Down Menus

A command pop-down menu is similar to a pull-down menu, but it appears within a window rather than inthe menubar. A commandpop-down menu presents a listof commandsthataffect the containingwindow’s contents. For example, the Colors window (shown in Figure 15-45) contains a menu with commands that can be used to change the contents of the Colors window itself. (If your application uses the Colors window, don’t create your own menu with these same commands; see “Fonts Window and Colors Window” (page 229) for more information on the Colors window.)

Figure 15-45 A command pop-down menu in the Colors window

A command pop-down menu

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

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Controls

Command Pop-Down Menu Usage

Use a command pop-down menu only when the containing window is shared among multiple windows or applications and the menu contains commands that affect the window’s contents. For example, the Colors window (shown in Figure 15-45) can be used in any application. The items in its command pop-down menu allow users to make new palettes of colors available in the Colors window (the open command pop-down menu in the Colors window is shown in Figure 15-46).

Figure 15-46 An open command pop-down menu

Commandpop-downmenusshouldcontainbetween3and12commands. Theitemsinacommandpop-down menu do not have to be mutually exclusive.

Command Pop-Down Menu Contents and Labeling

Command pop-down menus do not require an introductory label. A closed command pop-down menu always displays the same text, which acts as the menu title. This is in contrast to a closed pop-up menu, which displays the currently selected item.

Command pop-down menus contain a single, downward-pointing arrow and may display check marks to the left of all currently active selections.

Command Pop-Down Menu Specifications

The specifications for command pop-down menus are the same as those for pop-up menus; see “Pop-Up Menu Specifications” (page 283) for the appropriate metrics. Figure 15-47 shows how the command pop-down menu text is positioned.

Figure 15-47 A command pop-down menu

Selection Controls

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