Type-In Pop-Up Menus (HI Guide)

Inside Macintosh: Macintosh Human Interface Guidelines / Part 2 - The Interface Elements: Chapter 4 - Menus / Pop-Up Menus

Type-In Pop-Up Menus

Sometimes it is useful to display a list of likely choices but still allow the user to type in a choice that you can't anticipate. Keep in mind that all preset choices should be visible so that people can make choices with mouse actions. The type-in option should be an additional choice when appropriate, not a requirement. You'll need to handle error checking and feedback for the typed data, as you would for a text entry field.

If the user types in an item that is already in the menu, place a checkmark next to the menu item. When the menu is open, highlight the item in the text box and the corresponding item in the menu. This behavior prevents a quick look in the menu from accidentally wiping out the previous value. It also reinforces the idea that choosing a different value in the menu changes the value in the text box. You don't need to highlight the title of the menu in this situation. The standard pop-up menu lends itself readily to this extension,
as shown in Figure 4-51.

Figure 4-51 A type-in pop-up menu

If the value typed into the text box does not match any of the items in the pop-up menu, add the type-in value as the first item and separate it from the standard values by a gray or dotted line, as shown in Figure 4-52. This item disappears from the menu when the user selects a standard value from the pop-up menu. Separating the custom item from the standard items makes a clear distinction between the items that are always available and the typed-in value, which is only temporary.

Figure 4-52 A type-in pop-up menu with user's choice added