I represent a list of items. My instances are presented on the display screen in a rectangular area. The user points to an item, pressing a mouse button; the item is highlighted. When the button is released, the highlighted item indicates the selection.

	basic control sequence
	controlActivity readKeyboard startUp startUpCenteredWithCaption: startUpSegmented:withCaption:at: startUpWithCaption: startUpWithCaption:at:

	displaying
	displayAt:withCaption:during:

	marker adjustment
	manageMarker markerOff markerOn: markerTop: scrollIntoView:

	private
	computeForm computeLabelParagraph labels:font:lines: menuForm rescan

	selecting
	selection setSelection:

	dialogs
	confirm: confirm:orCancel: confirm:trueChoice:falseChoice: inform: notify:

	instance creation
	labelArray: labelArray:lines: labels: labels:lines: withCaption:chooseFrom:

	accessing	top
	center Answer the point at the center of the receiver's rectangular area.
	frameHeight Designed to avoid the entire frame computation (includes MVC form), since the menu may well end up being displayed in Morphic anyway.
	labelString
	lineArray
	nItems

	basic control sequence	top
	controlActivity Do whatever a menu must do - now with keyboard support.
	readKeyboard Keyboard support for menus. ESC will abort the menu, Space or CR will select an item. Cursor up and cursor down will change the selection. Any other key will either select an item whose label starts with that character or select the next matching label. Answer true if the menu should be closed and false otherwise.
	startUp Display and make a selection from the receiver as long as the button is pressed. Answer the current selection.
	startUpCenteredWithCaption: Differs from startUpWithCaption: by appearing with cursor in the menu, and thus ready to act on mouseUp, without requiring user tweak to confirm
	startUpSegmented:withCaption:at: This menu is too big to fit comfortably on the screen. Break it up into smaller chunks, and manage the relative indices. Inspired by a special-case solution by Reinier van Loon.
	startUpWithCaption: Display the menu, slightly offset from the cursor, so that a slight tweak is required to confirm any action.
	startUpWithCaption:at: Display the menu, with caption if supplied. Wait for the mouse button to go down, then track the selection as long as the button is pressed. When the button is released, answer the index of the current selection, or zero if the mouse is not released over any menu item. Location specifies the desired topLeft of the menu body rectangle.

	displaying	top
	displayAt:withCaption:during: Display the receiver just to the right of aPoint while aBlock is evaluated. If the receiver is forced off screen, display it just to the right.

	marker adjustment	top
	manageMarker If the cursor is inside the receiver's frame, then highlight the marked item. Otherwise no item is to be marked.
	markerOff No item is selected. Reverse the highlight if any item has been marked as selected.
	markerOn: The item whose bounding area contains aPoint should be marked as selected. Highlight its area and set the selection to its index.
	markerTop: Answer aPoint, gridded to lines in the receiver.
	scrollIntoView:

	private	top
	computeForm Compute and answer a Form to be displayed for this menu.
	computeLabelParagraph Answer a Paragraph containing this menu's labels, one per line and centered.
	labels:font:lines:
	menuForm Answer a Form to be displayed for this menu.
	rescan Cause my form to be recomputed after a font change.

	selecting	top
	selection Answer the current selection.
	setSelection:

	class initialization	top
	initialize PopUpMenu initialize
	setMenuFontTo: Set the menu font as indicated

	dialogs	top
	confirm: Put up a yes/no menu with caption queryString. Answer true if the response is yes, false if no. This is a modal question--the user must respond yes or no.
	confirm:orCancel: Put up a yes/no/cancel menu with caption aString. Answer true if the response is yes, false if no. If cancel is chosen, evaluate cancelBlock. This is a modal question--the user must respond yes or no.
	confirm:trueChoice:falseChoice: Put up a yes/no menu with caption queryString. The actual wording for the two choices will be as provided in the trueChoice and falseChoice parameters. Answer true if the response is the true-choice, false if it's the false-choice. This is a modal question -- the user must respond one way or the other.
	inform: PopUpMenu inform: 'I like Squeak'
	notify: Deprecated. Use #inform: instead.

	instance creation	top
	labelArray: Answer an instance of me whose items are in labelArray.
	labelArray:lines: Answer an instance of me whose items are in labelArray, with lines drawn after each item indexed by anArray. 2/1/96 sw
	labels: Answer an instance of me whose items are in aString.
	labels:lines: Answer an instance of me whose items are in aString, with lines drawn after each item indexed by anArray.
	withCaption:chooseFrom: Simply put up a menu. Get the args in the right order with the caption first. labels may be either an array of items or a string with CRs in it. May use backslashes for returns.