UI Object UIDropDownMenu

From WoWWiki

A dropdown box created using UIDropDownMenu.

UIDropDownMenu is a FrameXML Frame template that can be used to create contextual menus and dropdown boxes in World of Warcraft. The relevant API is highlighted on this page.

The menu architecture

The "MENU" style for context menus.

FrameXML provides a template -- UIDropDownMenuTemplate -- that all menu or dropdown boxes should inherit from. Once a frame has been created, a menu initializer function needs to be bound to it using UIDropDownMenu_Initialize. This process uses the frame object to store limited menu-related data, and applies the desired menu style. Note that most of the usual frame-related methods may not work as expected on the dropdown menus, so additional API is provided to perform functions such as setting the selected entries, text, or adjusting dropdown box appearance.

The menus themselves are displayed using FrameXML-owned frames. Because of this, representations menu representations generally do not exist in memory unless the menu is open, and only one menu may be open at a time. The initialization function provided to UIDropDownMenu_Initialize is used to create the required menu's controls when that menu is opened.

To implement a dropdown menu or list, one typically needs to create a frame inheriting from UIDropDownMenuTemplate, implement an initialization function to create the relevant menu controls when needed, and bind the initialization function to the frame using UIDropDownMenu_Initialize.

General API

UIDropDownMenu_Initialize(frame, initFunction, displayMode, level, menuList)

Initializes a dropdown menu attached to a specific frame.

frame: Frame handle the menu will be bound to.
initFunction: Function called when the menu is opened, responsible for adding menu buttons. Signature: (frame, level, menuList); additional global variables are used to communicate menu state.
displayMode: "MENU" to use context-menu style, any other value to create a dropdown list box.
level: 2nd argument to the initialization function when called for the first time.
menuList: 3rd argument to the initialization function; used by EasyMenu.

UIDropDownMenu_AddButton(info, level)

Add a button to the currently open menu.

info: Table describing the button: key/value pairs listed below.
level: Number specifying nesting level; can typically reuse the level argument to initFunction.

ToggleDropDownMenu(level, value, dropDownFrame, anchorName, ofsX, ofsY, menuList, button)

Opens or closes a menu; arguments marked as internal are used from within the UIDropDownMenu implementation to open sub-menus etc.

level: Internal - level of the opened menu; nil for external calls.
value: Internal - parent node value for the sub menu; nil for external calls.
dropDownFrame: Both - dropdown menu frame reference (menu handle).
anchorName, ofsX, ofsY: Both - Positioning information (anchor and x,y offsets) for context menus.
menuList: Internal - EasyMenu wrapper argument, passed as the third argument to the initialization function.
button: Internal - Dropdown menu "open" button.

Initialization functions

The initFunction supplied to UIDropDownMenu_Initialize is called when the menu (as well as any nested menu levels) should be constructed, as well as as part of the UIDropDownMenu_Initialize call (this allows you to use the selection API to specify a selection immediately after binding the function to a menu frame should you so desire). The function is given three arguments:

frame: Frame handle to the menu frame.
level: Number specifying nesting level.
menuList: An EasyMenu helper argument that can safely be ignored.

Additionally, some global variables may be useful to determine which entry's nested menu the initializer function is asked to supply.

It is expected that the initialization function will create any required menu entries using UIDropDownMenu_AddButton when called.

The info table

Bolded keys are required.

Key	Value type	Description
text	String	Button text for this option.
value	Any	A value tag for this option.
func	Function	Function called when this button is clicked. The signature is (self, arg1, arg2, checked)
arg1, arg2	Any	Arguments to the custom function assigned in func.
isTitle	Boolean	True if this is a title (cannot be clicked, special formatting).
disabled	Boolean	If true, this button is disabled (cannot be clicked, special formatting)
hasArrow	Boolean	If true, this button has an arrow and opens a nested menu.
hasColorSwatch	Boolean	If true, this button has an attached color selector.
r, g, b	Numbers [0.0, 1.0]	Initial color value for the color selector.
colorCode	String	cffabcdef" sequence that is prepended to info.text only if the button is enabled.
swatchFunc	Function	Function called when the color is changed.
hasOpacity	Boolean	If true, opacity can be customized in addition to color.
opacity	Number [0.0, 1.0]	Initial opacity value (0 = transparent).
opacityFunc	Function	Function called when opacity is changed.
cancelFunc	Function	Function called when color/opacity alteration is cancelled.
notClickable	Boolean	If true, this button cannot be clicked.
notCheckable	String	If true, this button cannot be checked (selected)
keepShownOnClick	Boolean	If true, the menu isn't hidden when this button is clicked.
tooltipTitle	String	Tooltip title text. The tooltip appears when the player hovers over the button.
tooltipText	String	Tooltip content text.
justifyH	String	Horizontal text justification: "LEFT", "CENTER", "RIGHT".
fontObject	Font	Font object used to render the button's text.

Selection functions

To use the _SetSelected* functions, your dropdown menu must be the currently open / currently being initialized. Otherwise, the functions will not have the desired effect.

UIDropDownMenu_SetSelectedName(frame, name, useValue): Sets selection based on info.text values.
UIDropDownMenu_SetSelectedValue(frame, value, useValue): Sets selection based on info.value values.
UIDropDownMenu_SetSelectedID(frame, id, useValue): Sets selection based on button appearance order.
UIDropDownMenu_GetSelectedName(frame): Returns selected button's text field.
UIDropDownMenu_GetSelectedID(frame): Return selected button's ID.
UIDropDownMenu_GetSelectedValue(frame): Returns selected button's value field.

Layout functions

UIDropDownMenu_SetWidth(frame, width, padding): Adjusts dropdown menu width.
UIDropDownMenu_SetButtonWidth(frame, width): Adjust the dropdown box button width.
UIDropDownMenu_SetText(frame, text): Alters text displayed on the dropdown box.
UIDropDownMenu_GetText(frame): Return text displayed on the dropdown box.
UIDropDownMenu_JustifyText(frame, justification): Adjusts text justification on the dropdown box.

Global variables

UIDROPDOWNMENU_OPEN_MENU: Frame handle of the currently open menu.
UIDROPDOWNMENU_INIT_MENU: Frame handle of the currently menu currently initializing.
UIDROPDOWNMENU_MENU_LEVEL: Current menu nesting level.
UIDROPDOWNMENU_MENU_VALUE: Value of the parent node.
UIDROPDOWNMENU_SHOW_TIME: Number of seconds to keep the menu visible after the cursor leaves it.